Lactose Powder Processing

Lactose is one of the main constituents of animal milk, acting as an energy carrier in milk. And due to its physiological and functional characteristics, lactose made in the industries is being used on a large scale in the food category and in the pharmaceutical industries. Lactose is made from whey, a byproduct of casein production and cheese making, by crystallizing the oversaturated solution of whey concentrate. The world’s production amounts to almost 500,000 tons and more. Lactose is the most abundant constituent after water, also the main carb in the milk of virtually all mammalian species.

Lactose content in dairy foods.

Cow milk has 4% to 5% lactose, so a large part of the dry matter content of the milk is covered by lactose. Pure lactose forms large, hard crystals which have a low solubility. For these reasons, lactose is also known as sand sugar. 

Uses of lactose

    • Lactose is massively used in the food and pharmaceutical industries.
    • In food industries, it is used for relative sweetness and being a source of energy.
    • Lactose maintains the crystallized sugar texture without causing the food to become too sweet.
    • Lactose is used in the confectionery industry to produce caramel flavors through the Maillard reaction, usually with milk proteins, often added with lactose in the form of sweetened condensed milk.
    • Lactose can be used in many products, like dairy products, dried soups, and sauces, jam, mayonnaise, and candy.
    • Lactose applications range from an energy source for lactic acid bacteria during dairy product fermentation, in which its breakdown leads to the formation of specific components. 

Dry Lactose Processing

The quality of the dry lactose (powder form) entirely depends upon the whey. In dry lactose manufacturing units, whey imported from different dairy units and it is tested on daily basis for pH, nitrates, and temperature. Only after detailed analysis in the QA laboratory, the whey enters the processing area. Whey gets stored in large holding tanks with temperatures below 6°C to maintain the functional benefits of the whey and ensure optimal microbiology.

Dry lactose powder 

In processing, whey is subjected to advanced separation and filtration mechanisms to bring out the desired features. By leading the Whey through a network of membranes, we separate the liquid into Retentate for protein ingredients and permeates for lactose ingredients. After separation from Retentate, Permeate is refined and concentrated then the concentrated liquid will be sent for crystallization.  After crystallization, the moist lactose material is led to the advanced bed dryers, here hot air flows through the product until the leftover water is dried out. The finished product is then bagged automatically, with no contact with human hands. 

Lactose Production


        1. Pre- Preparation of Whey

Lactose can be made from whey as well as whey permeate. Before the whey permeate can be used to derive lactose, fine cheese parts and the present amount of fat will be separated as Whey cream. And when the whey permeate will be used, then the proteins of whey will be removed by the process of ultrafiltration.


        1. Evaporation 


Then the whey or whey permeate will be concentrated by means of evaporation at a temperature of almost 60deg.c, until the dry matter content reaches 60-62%. Lactose concentration gets increased after this process. During the evaporation of whey, the temperature would not be raised further just to prevent the proteins from denaturation. If required, the whey permeates will be pre-concentrated.



        1. Crystallizing 

Lactose process-crystallization 

After evaporation, the whey or whey permeate will move further for crystallization. In the crystallization tank, ent-crystals will be added and conditioned cooling will take place in order for the whole to crystallize due to supersaturation. The cooling speed should not be too high, just to ensure the crystals formed should be of minimal size 0-2mm.


        1. Decanting and Washing

Lactose process-decantation (removal of water & impurities)

After crystallization, the formed lactose crystals will be separated using mother liquor by means of two decanters placed in the sequence. In the second decanter, all the impurities will be removed from the lactose crystals using washing water.


        1. Drying 

After the decanter, lactose will move further toward the drying section. To lower the moisture content, the lactose will be dried after the second decanter by using Fluid type bed dryer. Depending upon the application, drying will take place until the moisture content reaches between 0.1 to 0.5%. For producing α-lactose, hot air drying will take place for the duration of 15 to 20 minutes without heating the product over 92°C and prevent the formation of β-lactose.

Dried lactose is then coolest and transported by means of dry air with a temperature of approx. 30°C. Fine matter in the sucked air is separated by means of a bag filter and will be transported back to the drying section.

Fluid-type bed dryer 

        1. Grinding 


After drying, the final product is sent for grinding to the desired size and wrapped in sacks.



There are abundant uses and functionalities of lactose, not just in our daily lives but also in the Industrial world.

  • The preferred type of milk for producing good quality/quantity lactose is Non-fat skimmed milk.
  • Lactose is later fermented and can be used to produce foods like cheese, yogurt, kefir, and acidified (sour) milk. Lactose is also preferred to produce lactic acid, which has a number of uses in the pharmaceutical, cosmetic, and food industries. The process of fermentation involves adding lactic acid bacteria (and less commonly, yeast) to milk or to a milk product.
  • Lactose is commonly used as a Cutting agent, which is prevalent in illegal drug production. And the substances used for this process are typically less expensive than the recreational drugs itself.
  • Lactose intolerant is a term where a human body is unable to break down and digest lactose that’s consumed in milk and other dairy products. The condition usually causes discomfort in the stomach. A body becomes lactose intolerant when it doesn’t produce enough lactase enzymes.
  • The main benefit of lactose-free milk is allowing people with lactose intolerance to enjoy milk and dairy products without triggering uncomfortable symptoms.



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