Acidity Regulator And It’s Application In The Food Industry

Type of acidity regulators

"There are around 200 plus acidity regulators allowed to be used in different food products by the FSSAI. Some of the examples are:

• Citric acid (INS 330) is most widely used in foods and is normally prepared by the fermentation process of carbohydrates by fungal microbes known as Aspergillus niger. Other sources of citric acid include citrus fruits such as lemons. It is mainly used as an acidity regulator as well as an aroma compound. In addition, Citric acid can be used to prevent oxidation reactions which result in the browning phenomena in foods such as salads.

• Lactic acid (INS 270) is naturally occurring in many fermented foods (first isolated from sour milk), produced commercially by microbial fermentation of carbohydrate substrates. Lactic acid is commonly available in liquid form (50-80% concentration), clear colourless to pale yellow solution. It has a specific sour taste and no strong smell, giving well balanced, less sharp, and nice acidity in the final product. It is very well soluble in water. It is also available in powder form.

• Acetic acid (INS 260) the most commonly known organic acid, naturally present in many fruits and fermented foods, is found in vinegar. Acetic acid is available in a liquid form and in high concentrations it is strongly corrosive. It can be produced by fermentation (natural acetic acid) or by synthesis. It has a very intensive specific pungent smell and taste and commercially is used as 6-10% solution. It is applied in many food products as a natural preservative.

• Malic acid (INS 296) is naturally occurring in many fruits’ organic acids (first isolated from apples), produced commercially by synthesis. DL malic acid is colourless and odourless and can exist in crystal or granulated form, it has a strong acid taste very well boosting fruit flavours, especially citrus taste. Malic acid is well soluble in water.

• Calcium acetate (INS 263) has several functions. It is used in some foods as a thickening agent (cake mixtures, puddings, pie fillings), but can act as a buffer in controlling the pH of food during processing, as a preservative to prevent microbial growth, and as a calcium supplement in pet products.

• Fumaric acid (INS 297) is naturally present in live cells’ chemical compounds (various fungi) and is also present in some fruits and vegetables. Commercially produced by chemical synthesis from malic acid. It is a crystalline, odourless substance non-hygroscopic and with limited solubility in water.

• Tartaric acid (INS 334) in the form of its salts, such as potassium hydrogen tartrate, finds most of its applications in the production of emulsifiers used in the baking industry and in confectionaries. Tartaric acid is colourless and odourless crystal, that has a strong and sharp acid taste. Tartaric acid is well soluble in water. It is produced synthetically using maleic anhydride, and can also be obtained naturally by extraction from wine products.

• Phosphoric acid (INS 338) is an inorganic acidulant obtained by a chemical reaction from phosphorus rock. It gives a very strong acid taste in low concentrations. Commercially is available in liquid form and most commonly in 70-80% concentrations. Food-grade phosphoric acid is a colourless clear liquid.

Physical and chemical properties

Fig: Physical and chemical properties of food acids

APPLICATIONS:

The pH of food determines its taste; it is known that acidic foods (e.g., citrus fruits and sour milk) taste sour while alkaline foods (e.g., baking soda) taste bitter (Seuss and Martin 1993). Acidity regulators have been employed in food processing industries as buffering agents. They adjust and maintain the acidity or alkalinity of a specific type of food product at a desired level for the purpose of either giving a specific taste or preventing microbial attack (Sofos and Busta 1981; Blocher and Busta 1985). The most commonly used acidity regulators are the weak organic acids including citric acid (in fruits, vegetables, and soft drinks; Palmer and List 1973); acetic acid (in margarine, butter, and curry powder; Tavares et al. 2005); fumaric acid (in bread, wine and jams; Kenney 1991); lactic acid (in milk and cheese; Datta et al. 1995); tartaric acid (in juices and bakery products; Palmer and List 1973); malic acid (in jams and tinned fruits; Kenney 1991); and calcium acetate, which also plays the important roles of the antioxidant booster, gel property enhancer, and thickening agent (Tavares et al. 2005).

The antimicrobial effect of food acidity regulators is a notable aspect of food preservation and safety. Food acidity regulators, also known as acidulants, are additives that help regulate the pH level of food products. These regulators play a significant role in inhibiting the growth of various microorganisms, thereby extending the shelf life of food items and enhancing their safety.

When acidity regulators are added to food, they create an environment with a lower pH, which is unfavourable for the growth and survival of many bacteria, yeasts, and moulds. Microorganisms have specific pH ranges in which they thrive, and altering the pH through the addition of acidity regulators disrupts their growth and metabolic activities. This preservation mechanism helps prevent spoilage and deterioration of food products. The antimicrobial effect of acidity regulators is particularly prominent in products like sauces, dressings, beverages, canned foods, and baked goods.

It’s important to note that while acidity regulators can inhibit the growth of microorganisms, they might not be sufficient on their own to ensure complete food safety. Other preservation methods such as refrigeration, heat treatment, and packaging also play vital roles in preventing microbial growth and ensuring the overall quality of food products.

Conclusion

Generally, acid regulators are used as pH control agents. There are a number of acid regulators and their salts that can be added within regulated concentrations to get desired effects in various foods, mainly as antimicrobial agents, conditioners in some foods, flavour enhancers, flavouring agents (acidic), or pH control agents. However, their affectivity is dependent on the type of food to which it is added, the solubility of acidulants, and their behaviour under different conditions of the food system.