Carbonated Beverages

People in the past believed that natural springs which were naturally carbonated, could cure many diseases. As such, scientists and inventors thought of ways to artificially produce these mineral waters.  Artificially produced carbonated beverages get their start from this. The first carbonated beverages were just non-flavored carbonated water sold as mineral water tonics.

Flavored carbonated drinks/ soft drinks were initially introduced in the United States in the early 1800s. The purpose of adding flavour was not just to make it taste better, but also to improve on the supposed natural curative properties of mineral water.  Popular ingredients to add were birch bark, dandelions, ginger, lemon, coca, and kola (the latter two combined ended up producing Coca-Cola).

Obviously, as the name explains carbonated beverages are those drinks that have carbon dioxide added to them. Carbon dioxide is a colourless and odourless gas. Usually, flavours and sweeteners are added to them to enhance their palatability. The water always has some amount of dissolved oxygen in it, but carbonated water is the one that is supersaturated with carbon dioxide.

The reaction between carbon dioxide and water produces carbonic acid. It is this carbonic acid that creates the tangling effect on your tongue. 

CO₂ + H₂O = H₂CO₃

1. Bubbling Effect/Sparkling Effect

The maximum amount of carbon dioxide that can get into the water is 8 grams per liter. The excess carbon dioxide will generally only stay in the water when the water is under pressure. Once the pressure is released (i.e. normal atmospheric pressure on the earth is restored), the carbon dioxide will start to escape. Once a bottle or can of a Carbonated Beverage is opened, giving the carbon some way to start escaping, it will, causing the beverage to go flat.

2. Ingredients

• Water

Water is the major ingredient in carbonated beverages. It comprises more than 90% of the total volume. The water which is used in the preparation of carbonated beverages must of very high potable standards. Therefore, water pre-treatment is necessary to ensure the high standards of finished beverages.  De-aeration of water is also required to facilitate subsequent carbonation and filling operations to minimize foaming problems.

• Sweeteners

The sweeteners impart flavour, improve the mouth feel, and adds calories to the beverage.  It is used in the form of sugar syrup and the final concentration of sugar varies between 8 to 14 percent in the finished beverage. 

• Carbon dioxide

 CO₂ gas is inert, non-toxic, almost tasteless, and is easy to produce. It is also available at a relatively lower cost in liquefied form. It is soluble in liquids where its solubility increases when the temperature of the liquid is decreased and it can exist as a gas, liquid, or solid. Purification of CO₂ is done by scrubbing with water to remove sulfurous compounds and passing through activated charcoal or carbon tower to remove odorous compounds. Many beverage manufacturers produce their own CO₂ on-site by using packaged systems.

• Acids

 Acids improve the flavour and also contribute towards the preservation of the beverage.  Kola beverages mainly use phosphoric acid for preservation and taste.

• Flavouring and Colouring agents

The flavouring component has a major influence on the flavour of the final product. They are used at very minor amounts (0.01 to 0.02 %). The nature of flavouring usually is determined by the type of the product. Fruit flavours are most commonly used, except in colas, which are flavoured by extract of cola root together with about 10% caffeine and a mixture of essences. Fruit flavour may be added in the form of juice, as comminuted (in the case of citrus fruit), or as an essence.

Important colouring agents for carbonated beverages synthetic colours particularly certified coal tar colours. Caramel obtained from heated or burnt sugar is a non-synthetic colour and is widely used in cola beverages. Permitted food dyes are generally preferred over natural fruit colours because of their greater colouring power and stability.

• Emulsifiers, stabilizers, and clouding agents

They are used to improve the stability of the solution, improve the appearance, etc. They should be added in appropriate proportion to ensure the quality of the product during storage. Gum Arabic and modified starches are the most common emulsifiers and stabilizers used in beverage emulsions. However, others include, xanthan, galactomannan, carrageenan, pectin, cellulose derivatives, and alginates

Foaming agents

 

The presence of foams at the top of the bottle for some beverages like cola is considered desirable. The most effective foaming agents are saponins which are extracted either from the bark of Quillaia or Yucca trees. The permitted level is up 200 ppm (in European Union) and 95 ppm in the USA.

3. Manufacturing Process

• Syrup Preparation

The syrup is usually prepared by mixing 1 part (volume) syrup to 3-6 parts (volume) water in stainless steel tanks fitted with agitators. In sugar-based products, syrup contains sugar syrup, citric acid, flavouring agents, preservatives, and water. It is initially heated to reduce the microbial load.

• Mixing

The syrup is pre-prepared, tested, and diverted to proportioner for mixing with water and carbonation. Flow meters are most frequently used for proportioning. The syrup is dosed through a mass flow meter and the water dosing is done volumetrically by using a magnetic induction flow meter.

• Carbonation and Chilling

Carbonation is the impregnation of a liquid with CO₂ gas. The degree of carbonation is judged by the amount of effervescence produced and it is the most important characteristic of carbonated beverages. The level of carbonation varies between 1 to 4.5 volumes of CO₂ per litre of beverage accordingly. The maximum amount of carbon dioxide that can get into the water is 8 grams per liter, hence the carbonation is done under very high pressure and reduced temperatures.

• Bottle Filling

 Carbonated soft drinks are filled into either bottles or cans. Thick-walled, reusable, glass bottles were used for many years, but are being replaced by thin-walled, non-reusable glass and increasingly, PET bottles.

 

Carbonated beverages were initially considered to have medicinal properties. Almost all the initial producers of carbonated beverages were associated with pharmacies. On May 8, 1886, a  local pharmacist, produced the syrup for Coca-Cola, and carried a jug of the new product down the street to Jacobs’ Pharmacy, where it was sampled, pronounced “excellent” and placed on sale for five cents a glass as a soda fountain drink.  Today Coca Cola is one of the largest beverage companies in the world. And today,  carbonated beverages even if they are considered as just refreshing drinks, they are playing a crucial role in the food business.

 

Reference 

1. https://www.britannica.com/topic/soft-drink
2. https://www.britannica.com/science/carbonation
3. https://www.cooksinfo.com/carbonated-beverages
4. https://www.coca-colacompany.com/company/history
5. http://ecoursesonline.iasri.res.in/mod/resource/view.php?id=147625
6. https://www.delightedcooking.com/what-is-a-carbonated-beverage.htm
7. https://fruitprocessingmachine.com/portfolio-items/carbonated-drinks-production-line/