Reverse Osmosis: Application in Zero liquid discharge


In water-short areas, wastewater reclamation has emerged as a practical option. Water shortage has emerged as a major issue as the world’s population grows and natural water supplies get depleted. It has been forecasted that the global demand for freshwater will exceed the supply by 40% by 2030.

It is expected that water scarcity will increase from about one-third to nearly half of the global urban population in 2050. Recovery and recycling of wastewater have become a growing trend in the past decade due to rising water demand. Most of the cost-effective water purification has been made possible via membrane treatment. Reverse Osmosis membranes have been demonstrated to significantly reduce total dissolved solids, organic pollutants, viruses, bacteria, heavy metals, and other dissolved contaminants.

Wastewater reuse, not only reduces the quantity and environmental threat of discharged wastewater, but it also alleviates the impact on ecosystems generated by freshwater withdrawal. Wastewater is no longer regarded as pure waste that may harm the environment if recycled, but rather as an additional resource that can be used to achieve water sustainability.

2. What is Reverse Osmosis?

Reverse osmosis (RO) is a membrane-based separation method that uses difference in the permeability of the water’s constituents. The membranes are made of a synthetic substance that is semipermeable; some constituents pass through it very easily, while others pass through it less readily.

To remove a constituent from water, water is forced across the surface of a membrane, resulting in product separation, which is why reverse osmosis (RO) is the best of all membrane filtration methods.

Schematic diagram of the Reverse osmosis process


The RO technique is utilized to remove dissolved solids because traditional municipal treatment methods are unable to do so. In chemical and environmental engineering, RO is increasingly employed as a separation process to eliminate organics and organic contaminants from wastewater. 

  1. Application of Reverse osmosis

 The use of reverse osmosis in wastewater treatment is limited by the high running costs caused by membrane contamination. In the case of industrial wastewater, RO has been employed in industries where it is possible to increase process efficiency by recovering valuable components that can be recycled in the manufacturing process.

An RO plant for industrial usage has the following goals:

  • 50% desalination of seawater and brackish water
  • 40% ultrapure water production for the electronic, pharmaceutical, and energy production industries and
  • 10% decontamination systems for urban and industrial water.


Some common applications of RO system include the following:

 (a) Desalination of the sea and brackish water.

 (b) Generation of high-purity water for pharmaceuticals.

 (c) Generation of ultrapure fresh water for microelectronics.

 (d) Generation of processed water for beverages (beer, bottled water, fruit juices, etc.);

 (e) Processing of dairy products.

 (f) Waste treatment for the recovery of process materials such as metals for metal finishing industries and dyes used in the manufacture of textiles.

 (g) Water reclamation of municipal and industrial wastewater.

  1. How does Reverse Osmosis work?

In Reverse osmosis, cellophane-like membranes separate pure water from polluted water. When pressure is applied to the concentrated side of the membrane, purified water is forced into the dilute side, and the rejected impurities from the concentrated side being washed away in the rejected water.


Permeate (or product) water is desalinated water that has been demineralized or deionized. The reject (or concentrate) stream is the water stream that contains the concentrated pollutants that did not pass through the RO membrane.

Salts and other contaminants are not allowed to pass through the semi-permeable membrane as the feed water enters the RO membrane under pressure (enough pressure to overcome osmotic pressure), and they are discharged through the reject stream (also known as the concentrate or brine stream), which goes to the drain or, in some cases, can be fed back into the feed water supply to be recycled through the RO system to save water.

Permeate or product water is the water that passes through the RO membrane and typically has 95% to 99% of the dissolved salts removed from it.

4.1. Stages of RO systems


Every RO system includes different types of filtrations. There are many filtration stages in a RO system. In addition to the RO membrane, every reverse osmosis water system also includes a sediment filter and a carbon filter. Depending on whether the filters are used before or after the membrane, the filters are referred to as prefilters or post-filters.

Each type of system contains one or more of the following filters:

      • Sediment filterfilters out particles such as dirt, dust, and rust
      • Carbon filterReduces the amount of volatile organic compounds (VOCs), chlorine, and other pollutants in water that give it an unpleasant taste or odor.
      • Semi-permeable membraneup to 98% of the total dissolved solids.


4.2. Technical Requirements of a RO System

Several fundamental technical prerequisites for a RO system include:

      • Feed water needs to be prefiltered and pH adjusted. After prefiltration, the feed water’s TDS and suspended particles should be kept under the specified ranges.
      • The microbiological quality of feed and product water should be monitored. If microbiological quality levels are exceeded, the system should be cleaned.
      • Before disinfection, every system component needs to be mechanically cleaned. To ensure that chemicals used in disinfection are eliminated from the system, the proper tests should be run.
      • It is best to avoid using filters or ion exchangers downstream of RO units.
      • The chemical and microbiological quality of water should be evaluated at predetermined intervals during a production cycle.
      • The RO system should be constructed for continuous flow without traps, dead ends, and pipe sections that may gather stagnant water. Installation of in-line conductivity sensors at strategic locations is necessary for ongoing water quality monitoring. The equipment should be qualified, and the RO system should be validated periodically, as well as operated and maintained according to the manufacturer’s instructions so that it can consistently produce water with acceptable quality.


5. What contaminants will Reverse Osmosis remove from water?

Reverse osmosis may remove up to 99%+ of dissolved salts (ions), particles, colloids, organics, bacteria, and pyrogens from the feed water.

  • However, the RO system cannot remove 100% of bacteria and viruses.

Contaminants are rejected by a RO membrane based on their size and charge. A properly operating RO system will generally reject any contamination with a molecular weight greater than 200. (For comparison a water molecule has a MW of 18). Similarly, the higher the contaminant’s ionic charge, the less probable it is to flow through the RO membrane.

6. ZLD combined with RO

RO is a technique for cleansing contaminated water using a membrane and a pressure unit. Furthermore, RO generates a large amount of liquid discharge, i.e. saline water. The Zero Liquid discharge system is used to limit discharge into streams and create a self-sustaining system with zero effluents.



Zero-liquid discharge (ZLD) is a water treatment technique that purifies and recycles all wastewater, resulting in zero discharge at the end of the treatment cycle. It is a cutting-edge wastewater treatment technique that combines ultrafiltration, reverse osmosis, evaporation/crystallization.

ZLD eliminates any liquid waste from exiting the plant or facility perimeter, with most of the water recovered for reuse. ZLD eliminates the danger of pollution associated with wastewater discharge and maximizes water usage efficiency, achieving a balance between freshwater resource exploitation and aquatic environment protection.

In order to increase energy and cost savings, reverse osmosis (Ro) has been added into ZLD systems. However, while RO is far more energy efficient than thermal evaporation.

Reverse osmosis for ZLD/MLD is constantly evolving, and the most efficient plants now have two concentration stages. The filtered wastewater is first forced through semi-permeable membranes at pressures of up to 80 bar, which reduces the water content by 40 to 50%. The liquid is forced through membranes at ultra-high pressures of up to 120 bar during the second step of the process, which reduces the water content by an additional 30 to 40%. It means that by the time the concentrate enters the brine concentrator following the two-stage reverse osmosis process, the water content has been decreased by up to 60%.


  1. Conclusion

RO is the best and most efficient desalination technique available today. The goal is to use RO to recover as much water from evaporation as feasible. Evaporation and Crystallisation is the most basic type of ZLD system, aiming for 90% water recovery and 100% crystallisation.

RO is currently the best and most energy efficient desalination method available. The goal is therefore to recover as much water as possible before evaporation using RO. As RO recovery rises, the cost of ZLD decreases.

Since water supplies are increasingly scarce, reuse options are growing in popularity. In this perspective, zero-liquid discharge (ZLD) is a new strategy for reducing waste, recovering resources, treating toxic industrial waste streams, and helping minimize water quality consequences in receiving water streams.

Although ZLD systems can reduce water contamination and increase water supply, their industrial-scale applications are limited due to their high cost and high energy consumption. Membrane-based technologies are an appealing future solution for industrial wastewater reclamation in ZLD systems.

8. Reference :

Introduction to Pipe sizes and pipe schedule

  1. Introduction

Pipe size calculation is necessary for planning and identifying the pipe to be utilized during project execution. The size of the pipe is determined primarily by

  1. the flow rate required,
  2. the pressure of the piping system, and
  3. the end connection equipment.

Identification of pipe size is vital for transmitting the exact idea from the piping design team to the piping execution team for using the correct pipe size for spool production. Pipe size also has a significant impact on cost. Oversizing a pipe result in additional costs, more complex pipe design, more footing, and, in some cases, process difficulties.

In the field of engineering, there are many and varied materials & types of pipes used, each   with their own unique credentials, and often with their own sizing. This results in some confusion in the industry around the outside diameter of piping, and the sizing of required pipe supports. That is why understanding to pipe sizing is very important.

Pipe size in referred in various terms like – Nominal Diameter (DN), Nominal Pipe Size (NPS), or Nominal Bore (NB). However, despite having certain similarities and variances in terms of their uses and places of origin, these are all notations for pipe sizes.

  1. Pipe sizing

Pipe size is specified with two non-dimensional numbers,

      • Nominal Pipe Size (NPS)
      • Schedule Number (SCH)

And the relationship between these numbers determines the inside diameter of a pipe.

  • Nominal pipe size and its importance


The Nominal Pipe Size (NPS) is a North American standard size for pipes that are suitable for high or low pressures and temperatures. It defines the diameter of pipe. Nominal pipe size only refers to the outside diameter (OD) of a pipe. When it is said that pipe size is 2 NPS, it indicates any pipes with an outer diameter of 2.375-inch (or 60.3 mm), regardless of wall thickness and hence internal diameter.

Nominal pipe sizing

Nominal Bore (NB) and Nominal Diameter (DN) are sometimes used alternately with Nominal Pipe Size (NPS). Nominal Bore (NB) is the European equivalent for NPS. The Nominal Diameter (DN) for NPS 5 and larger is equal to the NPS multiplied by 25.

Pipe size illustration

2.1.1 Nominal diameter (DN): The Nominal Diameter (DN), is frequently referred to as “mean or average outer diameter.” The metric unit system uses nominal diameter, sometimes known as Diameter Nominal (DN). The pipe’s Inner Diameter (ID) and Outer Diameter (OD) are not equal to the nominal diameter.

Although not exactly equal, the value of DN is close to the inner diameter of the pipe. The connecting dimensions of pipes and pipe fittings are denoted using this notation. Pipes come in a variety of DN sizes, and using standard tables and pipe schedule charts, the DN is used to determine the pipe’s final dimensions.

NPS vs DN measurement

2.1.2 Nominal Bore (NB): A European standard for indicating pipe size is Nominal Bore, or NB. In the case of pipes, the terms bore, and nominal refer to hollow structures, respectively. The nominal bore is a rough internal measurement across the diameter of the pipe. In other terms, a nominal bore refers to the pipe’s bore’s approximation in size.

 A pipe is exactly 10.75 inches long when measured in inches; hence, 10.75′′ x 25.4 = 273.05 mm. This is the reason why the outside diameter is not a straightforward number like 250NB.

Pipe Size Indication

  1. What is schedule Number?

The wall thickness of the pipe is described using steel pipe schedules. This crucial variable as it is directly related to the strength of the pipe and the suitability for specific applications.  Given the design pressure and permitted stress, a pipe schedule is a dimensionless number which is derived using the design formula for wall thickness.

Pipe wall thickness is determined by pipe schedule. The mechanical strength of the pipe increases as the wall thickness, allowing it to withstand higher design pressures.

Schedule number = P/S

  • P is the service pressure in (psi)
  • S is the allowable stress in (psi)

Two pipes of the same diameter with different schedules will have different wall thicknesses. So, when specifying a pipe for a high-pressure application, a larger number signifies a larger schedule (wall thickness).

Pipe schedule illustration

The schedule numbers 40 and 80 are the most popular ones. As the schedule number increases, the wall thickness of the pipe increases. Since there has been advancement of industrial age, pipe sizes and their standard has also been changed. There is wide range of wall thicknesses: SCH 5, 5S, 10, 10S, 20, 30, 40, 40S, 60, 80, 80S, 100, 120, 140, 160, Standard (STD), Extra Strong (XS) AND Double Extra Strong (XXS).

Steel pipe schedules are a way to specify the pipe’s wall thickness. This is an important metric since it is directly related to the pipe’s strength and applicability for various applications. A pipe schedule is a dimensionless number that is calculated using the design formula for wall thickness and the permissible stress.

4.  Conclusion

Pipe sizing is one of the first important actions a process engineer performs throughout the P&ID preparation process.  Pipe size is a key consideration in a well-designed process. It will have an impact on fluid velocity, pressure drop, flow regime, and so on. A poorly sized pipe can disrupt the entire process and, in extreme situations, lead to plant shutdown That is why one should always know about the differences between Nominal pipe sizes and pipe schedule numbers.

5.  Reference

Introduction to Air Quality standards for the classification of Compressed air quality

  1. Introduction

ISO (International Standards Organisation) is the world’s largest developer and publisher of international standards. An intermediary between the public and private sectors, ISO is a non-governmental organization. It has developed international standards to test the quality of compressed air. There are now three standards in use that are specifically related that directly relate to compressed air quality (purity) and testing:

  1. ISO8573 Series
  2. ISO12500 Series
  3. ISO7183

The most used standard is the ISO8573 Series and in particular ISO8573-1:2010. The ISO air quality standard measures three types of contaminants present in compressed air: water, oil content, and solid particles. It does not consider microorganisms and gases.

2.     What is compressed air quality & why it is needed?

When air is gathered to be compressed, more particles are also gathered, resulting in contaminated air. When air is compressed, the number of impurities present exponentially rises. Additionally, when compressing air, other pollutants could be included. To clean up the compressed air system’s pollutants, air treatment is required. The types of contaminants found in a compressed air system include:

  1. Solid particles / Dust
  2. Water (in liquid or vapor form)
  3. Oil content (in vapor or aerosol form)

Schematic presentation of contaminants present in compressed air

When air is adequately treated, it is considered clean and safe. However, the quality of compressed air is determined not just by how clean it is, but also by how dry it is. The number of particles of a specified size present in one cubic meter of air, the dew point, and the number of oil aerosols and vapor must all be counted to assess how clean and dry the compressed air is.

Compressed air is utilized in a variety of industries, including mining, manufacturing, textile manufacturing, and food processing. The air quality utilized in industrial applications has a direct impact on the work process, installed machines, and product quality. As a result, it is critical that the compressed air be clean and devoid of pollutants.

The smaller the chance of contamination, breakdowns, and product rejection, the cleaner the air. This is especially important in businesses like food and beverage and pharmaceuticals. There is a possibility that the air will come into direct touch with the product or will come into indirect contact with the packaging.

  1. Classification of Compressed air quality

Compressed air is the only utility created by the end user of all the key utilities used in the food manufacturing setting. This means that the end-user has a direct impact on the quality of this energy source.

High-quality compressed air is essential for producing food that is not only cost-effective to process but also safe to consume. Therefore, choosing the appropriate compressed air equipment for food processors is in the best interests of everyone. The basis for choosing air treatment products is made much easier by the ISO 8573 air quality standards and ISO 12500 compressed air filter standards.


      Standards used for air quality measurement

  1. What is ISO 8573 & how it defines different air purity classes?

ISO 8573 is the compressed air quality standard. ISO8573 is a series of international standards that address compressed air quality (or purity). Part 1 of the standard describes the compressed air quality requirements, and parts 2 through 9 detail the testing techniques for various pollutants.

  • ISO 8573-1: Contaminants & purity classes
  • ISO 8573-2: Oil aerosol test methods
  • ISO 8573-3: Humidity test methods
  • ISO 8573-4: Solid particle test methods
  • ISO 8573-5: Oil vapor test methods
  • ISO 8573-6: Gas test methods
  • ISO 8573-7: Viable microbiological content tests
  • ISO 8573-8: Solid particle test methods by mass concentration
  • ISO 8573-9 Liquid water test method


       Various air quality classes


This above standard also determines air quality, which is designated by the following nomenclature: Compressed Air Purity Classes A, B, C:
A= Solid particle class designation
B= Humidity and liquid water class designation
C= Oil class designation

Air quality designation

5.     Why is it important to consider the air quality?

Compressed air can contain unwanted substances, such as water in drop or vapor form, oil in drop or aerosol form, and dust. Depending on the compressed air’s application area, these substances can impair production results and even increase costs. Air treatment aims to produce the compressed air quality specified by the consumer. When the role of compressed air in a process is clearly defined, finding the system that will be the most profitable and efficient in that specific situation is simple. This will be determined by your finished product and the working environment of your application.

6.     What does Class 0 mean for air quality?

It is recommended that only compressed air classified as Class 0 be used in critical processes to eliminate the risk of air contamination. This level of classification does not mean zero contamination. Class 0 refers to the highest air quality possible with minimum contamination present in the air and must be lower in contamination than Class 1.

A combination of compressed air equipment can be installed to produce clean air. This may include various air filters and dryers. Identifying which contaminants need to be removed will help you to determine which equipment you need.

  1. Conclusion:

A specific compressed air class is assigned depending on the number of contaminants found. The air quality class is set according to ISO 8573-1. This standardized system defines parameters from the least to most contaminated sources of compressed air. These standards are very much useful when it comes to selecting air compressors/ compressed air systems for industrial purposes. As Compressed air is a vital energy source and is utilized in multiple operations in a food processing facility.

When properly treated, compressed air is regarded as a safe, clean utility, as compared to other energy sources. It is ultimately used to package, wrap, seal, palletize and label food products prior to storage or shipment. ISO 8573 is a European Standard that describes contaminants in compressed air and defines purity classes for them. This multi-part standard also defines approved measurement methods for testing contamination levels.

  1. Reference


Insight into Food Quality Measurement

What is considered food quality?

Food Quality is the quality that the consumer finds acceptable in food service. The food quality parameter includes external elements like aspect (size, shape, brightness, and color), texture, and taste. Other features include internal components and legal quality standards (chemical, physical, microbiological). Many consumers base their decisions on production and processing norms, citing substances with dietary, medicinal, or nutritional requirements (for allergies or diabetes, for example). Food quality is intimately tied to health and hygiene standards and includes traceability and labeling.

Importance of Quality Control

  1. Decrease in production costs

Companies in the food sector can significantly lower their production costs by implementing effective inspection and control in the production processes and operations. Production expenses are further raised by wastage and poor product quality. Quality control monitors the creation of subpar goods and wastes, which significantly lowers the cost of production.

  1. Improved goodwill

Quality control boosts the company’s reputation in the public eye by creating goods of higher quality and meeting client needs. As a result, the brand gains a solid reputation and favorable word-of-mouth marketing on offline and online platforms. A well-known company can readily raise capital from the market. Additionally, a company’s chances of surviving in the fiercely competitive market are better with improved goodwill.

  1. Simplifies pricing

Companies in the food business can ensure that uniform products of the same quality are produced by implementing quality control techniques. This considerably simplifies the issue of food product price fixing. Additionally, this removes the concern over commodities’ prices fluctuating continually.

  1. Improved Sales

Quality control ensures that high-quality items are produced, which draws more customers to the product and boosts sales. It is crucial in sustaining and generating new demand for the company’s products. Additionally, increased social media usage has increased the need for brands to stay alert constantly. Any unfavorable feedback from a customer could harm the brand’s reputation.

  1. Improved Production Methods

Quality control ensures that goods are produced according to the desired standards and at reasonable rates. Quality control ensures better methods and designs of production by providing technical and engineering data for the product and manufacturing processes.

  1. Enhanced employee morale

An efficient quality control system is beneficial in raising staff morale. Employees are more inclined and motivated to work toward the firm’s goals when they believe they are employed by a company that produces sound, high-quality products. Additionally, these workers are more likely to adhere to the organization’s criteria for quality control in their work.

What are Food Quality Testing Parameters?

Any food characteristics used to gauge quality can be called quality parameters. However, the specific features assessed can vary since quality can mean different things to different people along the food supply chain.


The following parameters are commonly used in food quality testing:

These quality parameters are used alone or in various combinations depending on the needs of a stakeholder in the food supply chain.

Broad Categories of Food Quality Measuring Instruments 




A separate industrial sector is expanding with food science research and practice to create and deliver the precise instruments required to measure and monitor numerous quality indicators. One of the most widely used methods is near-infrared spectroscopy, which is suitable for determining the quality and quantity of organic molecules. Together with those made for post-harvest gas analysis, these tools are actively enhancing the production of fresh fruits and vegetables, paving the way for more earnings and more environmentally friendly practices.



FSSC 22000: A brief insight

What is FSSC 22000?

With the industrialization of food, there is an increasing need for affordable, safe, and good-quality food products. FSSC 22000 provides a brand assurance platform to the food industry. Food Safety System Certification 22000 (FSSC 22000) is an internationally accepted certification scheme for certifying and auditing food safety within the food and beverage industry. It is accepted worldwide because it is recognized by Global Food Safety Initiative (GFSI).

What is the backbone of FSSC 22000?

FSSC22000 is based on 3 components:

  1. ISO22000- Provides a basic framework across the entire framework.
  2. PRPs- Includes requirements derived from BSI, PAS, and ISO Technical Specification Standards.
  3. FSSC22000 Additional Requirements- Covers those requirements missed in ISO22000 and PRPs.

Aims and Objectives

  1. Create and maintain an accurate and reliable register of certified organizations that have demonstrated that they meet the system’s requirements.
  2. Support the accurate application of food safety and quality management systems.
  3. Promote national and international recognition and acceptance of food safety and quality management systems.
  4. Provide information and campaigns on food safety and quality management systems and support for the certification of food safety management systems in food safety and quality.

Which organizations can get FSSC22000 certification?

FSSC supports the whole food supply chain. It covers:

  • Processing of ambient stable products
  • Production of feed
  • Production of pet food (only for dogs and cats)
  • Production of pet food (for other pets)
  • Catering
  • Retail /Wholesale
  • Provision of transport and storage services for perishable food and feed
  • Provision of transport and storage services for ambient stable food, feed, and packaging materials
  • Production of food packaging and packaging materials
  • Production of Bio-chemicals

Difference between FSSC 22000 and FSSC 22000 QUALITY

Combining FSSC 22000 and ISO 9001 is called FSSC 22000 QUALITY. FSSC 22000 QUALITY is for an organization that wishes to integrate its Food Quality Management System into the scope of certification.

Audit and Certification Process of FSSC 22000

The certification process and audit proceeds according to the steps below:

  1. Initial Certification Audit – The initial certification audit includes: – fixing a mutually convenient date for both the certification body and the applicant, applicant, ensuring that it has all the required documents, staff members, and all the operations and processes ready to be audited on the audit day.
  2. The two Stages for the FSSC 22000 Audit –
    • STAGE 1: Stage 1 verifies that the applicant follows the FSSC 22000 standards, own internal documents, and regulations of the country. The applicant organization must have at least six months of verifiable records for the audit. After review, it will include “areas of concern,” which will be categorized as Major or Minor areas of concern. Finally, the applicant will have up to 6 months to fix the errors. The main objective of this stage is to assess the preparedness for stage 2 of the organization.
    • STAGE 2: In stage 2, activities subjected to the proposed certification shall be assessed and shall take place during the initial six months after stage 1. The site shall be fully operational during the audit. Applicants are issued with either Minor, Major, or Critical findings. In the case of Major and Critical results, the certificate will be issued once these issues are resolved.
  3. Certificate Issue – After all the issues have been resolved to the auditor’s satisfaction, the Certification Body shall issue a certificate which essentially gives assurance that all the standard’s requirements have been met.
  4. Surveillance Audits – After the certification is issued, annual surveillance audits shall be conducted within the three-year, of which at least one must be unannounced.
  5. Recertification Audits – Recertification audits are conducted every three years and usually coincide with a newer version of FSSC 22000. It is a complete audit that encourages the latest compliance and demonstrates the organization’s competence.


Why FSSC 22000?

  • Economical – Organizations can pay all at once or divide the payment over three years. It is economical compared to other schemes, such as British Retail Consortium (BRC), where the organization should pay annually.
  • Valid for three years – Once certified, the organization does not have to worry about certification for three years if they maintain the given standard.
  • Benefit of Surveillance Audit – The auditors will audit each year, which provides room for improvement, if any.


FSSC 22000 is designed to help an organization establish and control and improve its food safety management. The scheme is recognized by GFSI (Global Food Safety Initiative) and is accepted worldwide.

FSSC 22000 integrates quality management with food safety by including all the requirements of ISO9001, making it a one-stop solution for an organization that wishes to incorporate quality into the scope of certification.

It ensures visibility up and down the supply chain. The scheme has both flexibilities with accountability, meeting the needs of individual organizations.



Single Line Diagram (SLD)

1. Introduction

Single-line diagram (SLD) is also known as a one-line diagram. It is a high-level diagram that shows how incoming power is distributed to the equipment. It is the first step in preparing a critical response plan, allowing you to become thoroughly familiar with the electrical transmission system layout and design.

The single-line diagram also becomes your lifeline of information when updating or responding to an emergency. An accurate single-line diagram ensures optimum system performance and coordination for all future testing and can highlight potential risks before a problem occurs.

An effective single-line diagram will clearly show how the main components of the electrical system are connected, including redundant equipment and available spares. It shows a correct power distribution path from the incoming power source to each downstream load – including the ratings and sizes of each piece of electrical equipment, their circuit conductors, and their protective devices.

Whether you have a new or existing facility, the single-line diagram is the vital roadmap for all future testing, service, and maintenance activities. As such, the single-line diagram is like a balance sheet for your facility and provides a snapshot of your facility at a moment in time.

2. Scope of SLD

To give you an accurate picture of your electrical system, the single-line diagram information normally includes:

    1. Incoming lines (voltage and size)
    2. Incoming main fuses, potheads, cutouts, switches, and main/tiebreakers
    3. Power transformers (rating, winding connection, and grounding means)
    4. Feeder breakers and fused switches
    5. Relays (function, use, and type)
    6. Current/potential transformers (size, type, and ratio)
    7. Control transformers
    8. All main cable and wire run with their associated isolating switches and potheads (size and length of run)
    9. All substations, including integral relays and main panels and the exact nature of the load in each feeder and on each substation
    10. Critical equipment voltage and size (UPS, battery, generator, power distribution, transfer switch, computer room air conditioning)

3. Uses & Significance

Single-line diagrams are used by several trades including Electrical, Mechanical, HVAC, and plumbing, but the electrical one-line diagram is the most common. HVAC and plumbing riser diagrams are essentially one-line diagrams, but they go by different names.

An electrical single-line diagram is a representation of a complicated electrical distribution system into a simplified description using a single line, which represents the conductors, to connect the components. Main components such as transformers, switches, and breakers are indicated by their standard graphic symbol. The overall diagram provides information on how the components connect and how the power flows through the system.

4. Flow Diagram of SLD

Few parameters are considered while designing the flow of a single-line diagram to keep it simple & readable:

    1. Remember to use a single line to represent multiple conductors.
    2. Diagrams should start at the top of the page with the incoming source of a system’s power.
    3. Electrical symbols must be used while drawing the single-line diagram to make it simple & concise.
    4. No physical location or size representation is required of the electrical equipment only ratings and breakers sizes with the other equipment to be used should be written.

5. Designing of SLD

To Design a single-line diagrams for your facility Some steps need to be taken:

    1. Create an inventory of all the utilities & equipment used in the building.
    2. Verify its existence and that they are adequately available.
    3. Confirm loads are connected to emergency/standby feeders.
    4. Verify potential single points of failure.
    5. Evaluate design redundancy of critical systems
    6. Make a report that outlines the findings by site along with recommended actions.
    7. Provide a copy of the single-line electrical diagram in AutoCAD format
    8. An up-to-date single-line diagram is vital for a variety of service activities including:
    9. Short circuit calculations, Coordination studies, Load flow studies, Safety evaluation studies, All other engineering Studies, Electrical safety procedures & Efficient maintenance, etc.

6. Calculations Requirements for SLD

6.1.     Identify the appropriate symbols:

To draw and understand a single-line diagram you first need to be familiar with the electrical symbols. This chart shows the most frequently used symbols. For electric power networks, an appropriate selection of graphic symbols is the most important step.

6.2.    Draw the required system:

To draw the electrical single line diagram first we need all the information on electrical equipment and the supply of receiving power. The most important information to include is:

          • Incoming service voltage
          • Equipment rated current
          • Identification of names of equipment
          • Bus voltage, frequency, phases, and short circuit current withstand ratings
          • Cable sizes, runs of cables, and lengths
          • Transformer connection type, kVA, voltages, and impedance
          • Generator voltage and kW
          • Motor HP
          • Current and Voltage ratios of instrument transformers
          • Relay device numbers

6.3.    Related calculations:

To represent the three-phase system in a single line diagram various other cal. are required:

          • Calculation Of generator reactance
          • Calculation Of transformer reactance
          • Calculation Of transmission-line reactance
          • Calculation Of reactance of motors and other equipment etc.

7. Software’s used 

7.1 AutoCAD

AutoCAD Electrical has a schematic library and a single line diagram sub-library. This enables the user to place two different representations down of the same component.

7.2 ETAP

ETAP Single-Line Diagram / View is an intelligent user interface to model, validate, visualize, analyze, monitor, and manage electrical power systems, from high to low voltage AC and DC networks.

7.3 Eco-dial

It is a low voltage electrical installation design software developed by Schneider Electric. it is a user-friendly software that helps you optimize equipment and costs while managing operating specifications, all along with the design of your power distribution projects.

7.4 Microsoft Visio

Visio Professional or Visio Plan 2 are used to create electrical and electronic schematic diagrams.


8. Benefits of SLD:

    • Help identify fault locations which identify when to perform troubleshooting & simplify troubleshooting
    • Identify potential sources of electric energy during the distribution process.
    • Accurate single line diagram will further ensure the safety of personnel work
    • Meets compliance with applicable regulations and standards
    • Ensure safe, reliable operation of the facility

9. Reference:


Pasta Processing and their types

  1. Introduction

Pasta is a food typically made from an unleavened wheat flour dough mixed with water or eggs and formed into sheets or other shapes. Many different cultures have eaten pasta over a large number of periods. Most Italian-type pasta is made from semolina, a grain product taken from the endosperm of durum wheat during milling.

Many different types of meals can be created with pasta. It tastes good and fills your stomach. Pasta as food represents an inexpensive means of improving diet quality in developed countries and helps to reduce hunger problems in developing countries. The unique combination of properties of cheapness, ease of preparation, versatility, nutritive value, and long shelf life will ensure that pasta will continue to play a role of importance as world demand for cereals increases. 

  1. Processing and extrusion of pasta

Pasta products are manufactured by mixing flour with water and other ingredients into the homogeneous dough and extruding this dough through a variety of dies.

Pasta processing consists of three main unit operations.

  • Hydrating and mixing- kneading of semolina to make the dough (Formation of gluten network)
  • Shaping the dough through extrusion
  • Stabilizing the shaped pasta pieces, usually by using different dye



  1. Equipment used for Pasta Processing

Most pasta is manufactured by continuous, high-capacity extruders, which operate on the auger extrusion principle in which kneading, and extrusion are performed in a single operation.

3.1 Powder Blender

Mixing formula ingredients is often carried out in mixer seems to have better mixing results in commercial noodle production.


The paddle design is generally employed where friable materials are being blended. Horizontal noodle dough mixer consists of several elements: a centrally mounted horizontal shaft that rotates within a cylindrical container, paddles, ploughs mixing elements that are attached to the centrally mounted shaft, special openings at the top for feeding materials, manually tilt able tank operated.

  3.2. Rolling machine

The plate rolling machine is a type of metal forming machine which utilizes work rollers to produce sheet metal round processing and forming. The plate rolling machine is also known by plate bending roller. Rolling machine is used to roll the dough into thin sheets. Rolling machine helps to provide pasta of good texture


3.3 Extrusion machine or slitter machine

Inside the Extruder, the material is compacted, compressed as it moves forward towards the die. This occurs because the material is picked by rotating screw inside a stationery barrel which has grooves on its internal surface.

The grooves enable the sticky, plastic mass to move forward and mix thoroughly under controlled shear and temperature. Teflon dies tend to have too smooth surface and produce slippery pasta with too smooth surface and sauces do not adhere easily to such product.

 3.4   Drying machine

In the Drier Machine, the product is dried under controlled humidity so that drying is neither too slow nor too fast. Too slow drying of product will damage the product as the product is rendered sticky or moldy. Too fast drying will crack the pasta. It might be necessary to ascertain and control different drying times for different product to get optimal results.

A properly extruded and dried pasta product would be firm, but flexible enough to be bent to considerable degree before cracking. In general, product retains about 10% moisture after drying.

3.5   Cooling and Packaging

Before packing, it might be essential to cool the pasta coming out from the main dryer.  After drying pasta is then collected into cooling drum, where the machine adjusted to a programmed temperature. After sealing pasta move into a spiral freezer where they are Individually Quick Frozen at -45 degrees centigrade.

This is generally done by belt conveyors and cooling fans to remove the excess heat before final packing. Ideally, pasta should have no more than 10% moisture before packing to prevent mold growth.

  1. Types of Pasta

Pasta has become one of the most common foods in the Indian kitchens. Pasta is categorized in different types according to their shapes and sizes. There are different types of pasta available in market in which some of them are mentioned below.  Following are some types of pasta available in market.

Pasta is one of the most favorite foods for all age groups. Basic ingredients for the manufacturing of pasta which is typically used are flour, eggs, salts, and water. There are more than 300 types of pasta available in market based on their shapes and sizes, in which penne, spaghetti, farfalle is most commonly used. Pasta can be cooked by adding more and more vegetables in it or it can be consumed with sauces.

  1. Reference


Process Control System in Food Industry

  1. Introduction:

Process control systems (PCS) also known as industrial control systems (ICS) are an integral part of the food & dairy processing industries. It is basically a tool that ensures plant efficiency and reliability. Process control systems function as pieces of equipment along the production line during manufacturing that tests the process in a variety of ways and returns data for monitoring and troubleshooting.

Food and Dairy products have a very vast application which ranges from dairy products to beverages and even bakery items, to fulfill this large demand food processing equipment with a control system is used to execute the various unit operations necessary during a complete production cycle.

  1. Objectives:

The need to install a process control system is to improve the economics of the process by achieving, the following objectives:

    • Reduce variation in the product quality,
    • Achieve more consistent production and maximize yield,
    • Ensure process and product safety,
    • Reduce manpower and enhance operator productivity,
    • Reduce waste and
    • Optimize energy efficiency

Mainly two common classes of control actions are used in industries:

    1. Manual control: In manual control, an operator periodically reads the process parameter. When the value changes from the set value manual process are required to control the operating process.
    2. Automatic control: In automatic control, the process parameter is measured by various sensors & instrumentation which is controlled by using control loops.

All process control configurations whether manual, automatic, or computerized mainly have three essential elements:

    1. A measurement
    2. A control strategy
    3. A feedback element

Regardless of the nature of the product and process. Control in food processing has moved on from just attempting to control single variables, e.g., level, temperature, flow, etc., to systems that ensure smooth plant operation with timely signaling of alarms. Process control systems also work to gather and transmit data obtained during the manufacturing process.

These are:

    1. Supervisory control and data acquisition (SCADA)
    2. Manufacturing execution systems (MES)
    3. Enterprise resource planning (ERP)

  1. Supervisory Control & Data Acquisition (SCADA):

SCADA is one automation solution that can improve production efficiency and increase profitability. In the food processing industry, SCADA is used to ensure food quality and to achieve production goals. All phases of food preparation are typically monitored and controlled by SCADA. SCADA is also used to control the exact mix of ingredients as well as the time and temperature required to process foods. This prevents foods from being spoiled due to a heating process that was off by a few degrees. SCADA applications are also important in food production to document the fact that the production process meets industry standards and complies with governmental regulations.

Nowadays SCADA systems can do more than simply collect data and operate devices. They use artificial intelligence (AI) to analyze data and make decisions without the help of humans. They can operate in a cloud environment so that SCADA monitoring and control can be accomplished remotely by using tablets and smartphones.

SCADA is used to control and monitor all operational technology (OT) in the plant. And at the same time also sends and receives information from the MES or ERP system For Information that has to do with business planning & scheduling.

SCADA works in the following way:

    • SCADA begins by communicating directly with controllers in the field in real-time, typically through a PLC or RPU.
    • Then the SCADA system gathers all the data obtained from connectors in the field and transfers it to SCADA itself.
    • Later the data is shown graphically to operators that are executing whatever process.

There are many areas in food/dairy industries where SCADA is used to optimize production:

    1. Packaging
    2. Recipe Re-creation
    3. Maintaining Quality standards
    4. Visualization of products
    5. Creation of reports

4. Manufacturing execution systems (MES):

Manufacturing execution systems (MES) are computerized systems used in manufacturing to track and document the transformation of raw materials to finished goods. MES works as a real-time monitoring system to enable the control of multiple elements of the production process (e.g., inputs, personnel, machines, and support services).


MES software can do more for food and beverage manufacturing companies than traditional management. It can:

    • Optimize your shop floor on the go.
    • Identify issues or potential problems before they happen.
    • Integrate easily with existing systems.
    • Empower employees with the data and insights to make manufacturing smarter.
    • Remove non-value-adding actions and anecdotal evidence of losses.
    • Build a reputation of trust and quality with the supplier base using auditable, quality data.

Five things your food industry MES system should have:

    1. User-Friendly Operator Interfaces –The golden rule of developing software for the food processing industry plant floor is that must be easy to use.
    2. Integration to Production Equipment – Food manufacturing production equipment is filled with valuable data and can be used to streamline and optimize manufacturing processes.
    3. Offline Operating Capability- manufacturing processes are network dependent then they will come to a screeching halt if the network fails. MES should have offline operation capability in Your food industry.
    4. Food Industry-Specific Functionality – Modern MES systems and especially one developed specifically for the food manufacturing industry will manage more challenges, making them the ideal solution for your production management and data collection needs.
    5. Food Industry-Specific Modularity –In the same vein, a food industry MES system will likely feature software modules that align well with your production processes.
  1. Enterprise Resource Planning (ERP): 

Enterprise Resource Planning refers to a software system which are used for business management. An ERP system enables food companies to manage and optimize their business processes – from purchasing, accounting, finance, human relations, and production to logistics. In short, ERP is the software that keeps your business up and running.

An ERP software for the food industry helps you introduce new products to market faster and cheaper than competitors & also ensures absolute compliance to the food safety regulations.

There are a few must-haves in ERP System:

    1. The ERP software must be able to supply precise cost information for all components, such as finished products, joint products, and byproducts. This is essential for the calculation of material and manufacturing costs as well as for pricing.
    2. Make sure that the system does not have any problems with portraying and optimizing recipes, bills of materials, and product calculations.
    3. Evaluations, gross margins, monitoring of processes and products: only if essential information and key performance indicators can be retrieved from the ERP system at the press of a button will decision-makers be able to get the most out of their business.
    4. The software must allow automated handling of variable weights. Otherwise, you will run into problems in weight price labeling, especially with non-equalized products.
    5. Production planning must take requirements of the fresh goods production into account.

Advantages of ERP:

    • Cost reduction: Save the investments in your own server, other expensive hardware, and skilled staff (which are quite hard to find these days)
    • Savings in time: No need to worry about keeping your ERP system and the hardware up to date. This will save you precious time.
    • Scalability: Add or remove IT resources cost-efficiently and in a very short time.

Benefits of Process Control System: 

    • Reduces wastage of expensive compounds
    • Provides improved production reliability
    • Increases productivity & quality
    • Improve the consistency of the product
    • Minimize the influence of external disturbance
    • delivers the continuous data required to meet regulatory standards
    • Standardized business processes

7. Reference:

    • Process Control in Food Processing Article Written by Keshavan Niranjan, Araya Ahromrit and Ahok S. Khare


Enzymes In flour: And its Baking Application

  1. Introduction

Enzymes are proteins that act as biological catalysts. Catalysts are generally used to     accelerate the chemical reaction. An enzyme is a substance that acts as a catalyst in the living organism to regulate the rate of chemical reactions. Almost all proteins are enzymes, but all enzymes are not proteins. It helps to boost metabolism.

Enzymes are a kind of catalyst that can work within mild conditions of temperature, and pH and carry out chemical reactions at a high rate. Some enzymes are active without co- enzymes, but some are not. So, the types of enzymes that are inactive in the absence of its co-enzyme is called apoenzyme and enzymes that produce the active form of enzyme, in the presence of co- enzyme is called holoenzyme.


Apoenzymes + Co-enzymes           ⇒           Holoenzymes


  1. Types of Enzymes in Flour

Enzymes are usually added to modify dough rheology, gas retention, and crumb softness in bread manufacture. Enzymes used in bakery products to facilitate chemical reactions without undergoing any chance in their molecular structure.

Following are the types of enzymes present in flour:

                      2.1 Diastase/ Amylase

Diastase breaks and converts it into malt sugar. Diastase or Amylase is destroyed at 77    degrees centigrade. The amount of diastase in grain varies from year to year, depending on harvest conditions.

                     2.2 Protease

Protease is found in flour but also in malt and yeast. Proteins that cannot be dissolved in water can be converted by protease into another form. Due to presence of gluten, the dough becomes more elastic and softer and produces amino acids. Protease starts to work immediately after the dough is mixed.  It is mostly used to produce pan bread, cracker, wafer, and biscuits.

                      2.3 Lipoxygenases

Lipoxygenases is present in soy- flour, also has an oxidative effect on the gluten.

                      2.4 Hemicellulose, Pentosanes and Xylanases

Wheat flour contains about 2-3% pentosans that can bind up to 10 times of their weight of water. These pentosans belongs to the category of hemicelluloses.

  1. Application of Enzyme in Baking

Enzymes as technological aids are usually added to flour, during the mixing step of the bread-making process. The enzymes most frequently used in bread-making are the α-amylases from different origin.

Amylases and other starch-converting enzymes. The industrial processing of starch is usually started by α-amylases. Following are the enzymes added to the flour to enhance their processing and some other purposes.


There are various types of enzymes used in baking industries. Some of the enzymes are already present in different flours but for baking some enzymes are generally added for different purposes.

Following are the enzymes added to the flour during baking


 3.1 Maltase

Maltase is used to standardize the alpha amylase activity to most bread flour. Malted wheat or barley flour is added at the bakery.


3.2 Lipoxygenase

Lipoxygenases are present in soy flour that oxidizes the fat in flour to form peroxidases. Peroxidases bleach the flour pigments which result in crumb color.

3.3 Fungal Amylase

It is used to standardize the alpha amylase activity of bread flour. Fungal amylase is commonly used in dough conditioning.

3.4 Protease

Protease breaks down the gluten protein in wheat flour. For bread making this can improve gas retention, but with a tradeoff for less tolerance. 

3.5 Transglutaminase

Transglutaminase creates links between gluten molecules and strengthens the dough.

  1. Primary enzymes used for baking

 4.1 Enhance dough retention capacity and softness of the dough

Enzymes can be added to reduce mixing time, to decrease dough consistency, to assure dough uniformity, to regulate gluten strength in bread, to control bread texture and to improve flavor.

4.2 Modifiers of dough handling properties

Extra enzymes added to the dough improve control of the baking process, allowing the use of different baking processes, reducing process time. 

4.3 Dough strengthener

The main function of dough strengthener is it works like an emulsifier by bonding with proteins and help to improve the gluten strength. They are added to the dough to improve texture, symmetry, volume, etc. of the bakery product. 

4.4 Crumb softeners (anti-staling agents)

Enzymes are also used to delay the staling process, to reduce waste and ease pressure within the supply chain.

5. References



Noodles : Types of Flour and Manufacturing

  1. Introduction

 Noodles are staple foods in many regions of the world. Instant noodles were born and manufactured by Nissin Foods, in Japan, in 1958. It is made from an unleavened dough that is rolled flat and cut stretched, or extruded into long strips or of different shapes. Noodles are a long, thin pieces of food made from a mixture of flour, water, and eggs. Most noodle types share the typical processing steps of mixing ingredients, kneading, rolling, or sheeting the dough, and cutting it into pieces. Noodles are usually consumed in wet, boiled, steamed, or fried form.

Noodles is produced in over 80 countries worldwide. It is one of the most important staple foods in Asia. Asian noodles are evolved into various types and forms. Noodles or pasta are made from very simple formulas. Noodles manufactured in United States use eggs, but in other parts of the world, egg is not a required ingredient, in place of eggs, salt is used everywhere.

Noodles is a food represents an inexpensive means of improving diet quality in developed countries and helps to reduce hunger problems in developing countries. For the manufacturing of noodles, generally Durum wheat is used.

  1. Types of flour used for making Noodles 

Noodles are most versatile food items in the world. We can eat noodles either with vegetables or on their own. Noodles can be consumed with sauces to enhance their taste and it can also be consumed with lots of vegetables to enhance their nutritional value.

For making noodles, five basic ingredients are used: Water, Salt, eggs, oil, and the very important ingredient is flour. Different kinds of flour are used for making noodles for health, taste, and texture reasons. Following are the flour generally used for manufacturing of noodles.

2.1 All-purpose flour

All-purpose flour is the most common flour used for making different kinds of dishes. Just like the name suggests, it is good to use for all purposes. Benefits of using all-purpose flour is, its texture, color, and elasticity.

2.2 Semolina flour

Semolina is referred to as Noodle or Pasta flour because of its coarser texture. Semolina has very high gluten content which helps in binding and gives its firm texture. But the disadvantage of semolina flour for Gluten intolerant people can’t consume noodle made from Semolina flour. 

2.3 Whole wheat flour

Whole wheat flour is the ingredient which is mostly used for noodle manufacturing. This flour adds texture and nutrition along with this it is a healthier option, being less refined and containing lower carbs than other flour.  Wheat flour contains less calories than other refined kind of Noodles.



Wheat noodles are manufactured by mixing durum wheat flour, water, and salt. For making wheat noodles, wheat flour is the main ingredients, and their appearance and texture strongly depends on flour characteristics. Swelling and gelatinization characteristics of wheat flour determine whether the surface of noodles is sticky or hard.

2.4 Corn Flour

Corn flour is gluten free flour so, it is a good option for gluten intolerant patient. The noodles made up of corn flour has distinct taste of corn, also it creates a slightly grainer texture than wheat noodles. Corn- flour can be used for noodles making by mixing with other flour also.

2.5 Quinoa flour

Quinoa flour is the best flour made by grinding the grains into powder. It is the best flour because this flour all the health benefits including high protein, high fiber, low glycemic index, which is good for controlling blood sugar level.

2.6 Buckwheat flour

Buckwheat is like whole grain, but the main difference is that it is gluten- free. It is popular ingredient because of its nutritional value, it is high in minerals and antioxidants. The noodles made from this flour is basically chewy and grainy.

2.7 Rice Flour

Rice noodles have a long history. It can be used in different forms, such as, fresh dried, and instant noodles which provides variation by which rice is enjoyed in our diet. Rice is a staple food used all over the world. It delivers both benefits of gluten- free and low glycemic index.

2.8 Plantain Flour

Plantain is basically a variety of banana which is hybrid of two species, i.e., Musa acuminata and Musa balbiciana. The botanical name of plantain is Musa paradiciaca. Mature green plantain was processed into plantain flour. Plantain flour is made by peeling, washing, slicing, drying, and grinding of green plantain.

Instant noodles are classified into two types based on methods used for removal of moisture.

  1. Instant dried noodles
  2. Instant fried noodles

In dried noodles, the moisture of noodles is removed by the process of hot air drying to decrease the moisture content to about 8 – 12 %. Frying the noodles decreases the moisture content to about 2-5 %. But the disadvantage of frying is it contains about 15-20% oil. So, this is more susceptible to oxidation resulting in rancidity and have health issues due to higher oil and fat content.

There are different types of noodles present in market based on brands, in which Maggi -2-minute Noodles is most popular brand of instant Noodles in India. Because of busy lifestyle, easy to cook food is the need of the adults now-a-days. Eating nutritious food, incorporating physical activities and good taste is the key to maintain the healthy lifestyle.    

  1. Manufacturing of noodles

Noodle manufacturing comprises of mixing of raw materials, resting the dough, sheeting the dough into sheets, and gradually sheeting the dough into specified thickness and slitting into noodle strands.

For instant noodle preparation, strands are steamed and dehydrated by drying or frying followed by cooling and packaging. These are the following steps followed for the manufacturing of noodles:

3.1 Mixing and kneading                                                             

As a first step, the wheat flour made up of durum wheat goes into the mixing machine. Then, dough is kneaded with water at room temperature of about 20 to 30 degrees centigrade. Kneading machine mixes the ingredients slowly without causing friction or heating the dough. In more automated industrial process, kneading is made inside vats with a single rotating shaft for 15 to 20 minutes with a speed between 29 to 100 revolution per minute.

3.2 Roller belt

After mixing and kneading the dough it goes into rotating rollers to form sheets. This roller belt helps to distribute the noodles evenly. Then we leave the dough for a specific time to mature. As after rolling the thickness of roller reduces about 1 mm to 1.5 mm. This machine is suitable to produce flat pasta such as lasagna, Fettuccine, and Spaghetti.

3.3 Cutter/ Slitter Machine

Slitter machine is also named as Noodle cutter. It is a type of cutter which can slit dough sheets into noodles. Noodle cutting is the final procedure in noodle manufacturing, so it plays a crucial role. With the help of slitter these instant noodles are made even thinner. Slitter cut the noodles in strand generally of about 2 inches wide and 13 inches long.

3.4 Steaming Machine

Steaming of noodles can be done for around 4 to 5 minutes at 100 degrees centigrade. Steamed noodles are partially cooked by treating fresh noodles with either saturated or unsaturated steam before they are marketed. Steamed noodles are prepared using a semi-automatic steamer.

3.5. Dehydration process

After steaming, most of the noodles are dehydrated either by oil frying or by air drying, thus fried or un- fried noodles is formed. Drying of noodle is very important and risky process because when the noodle is too dried it will break down and if it is dried too slowly it will spoil.

3.6 Cooling

After steaming the noodles, it should be goes through the cooling machine for further cooling of noodles. It should be kept in cooling machine for 4-5 minutes.

3.7. Packaging

The dried and cooled noodles are then put into firm bags and containers as required and then it is used for packaging. The instant noodles can also be garnished and packed into plastic bags. Then the packed noodles can be transported in market for sale.

  1. Shelf life of Noodle

Shelf life of noodles depends on various factors like best-by-date, preparation method and how it was stored. Shelf life of dry pasta is roughly about 1 to 2 years and cooked or processed noodles is about 4 to 5 days in freezer and 1 week in refrigerator. 

  1. Nutritional benefits of Noodles

Noodles are generally very low in calorie and fiber. It is a good source of energy. Noodles can help with stomach problems, and it may help lower cholesterol. Cooked noodles contain 34% carbohydrate, 6% protein, low amount of fat with moderate amount of manganese.

5.1 Sustained Energy

Cooked noodles provide 34% carbohydrates which is a crucial fuel for our brain and muscle. It releases energy in a slow and sustained level. It is consumed by the players before playing to enhance their energy level.

5.2 Low sodium and cholesterol free

The amount of sodium is very low in noodles, and it is cholesterol free.  It helps with stomach problems. Noodles is a good source of several essential nutrients including iron and B- vitamin.

Noodles contain 6% protein and low amount of fat. It is a good source of complex carbohydrate. It can be consumed to enhance calorie. Noodles can be combined with vegetables for a complete meal that puts you well on the path of hitting dietary goals.

  1. Reference