Food Chemistry. Группа авторов

use either number or name in the food labels. The E number does not indicate whether the additive is a natural or synthetic compound but category of the compound can be identified with the E number. For example, coloring agents have E number between 100 and 180, 500, to 1,520, which includes acids, alkalis, flavor enhancer, and additives with various other functions.

Table 2.1 Food additives and its sources.

Source of food additives	Example of food additives
Plant origin	i. Acidulant as tartaric acid from fruitii. Color from fruits and vegetablesiii. Thickening agent from seaweed, fruit and seeds
Nature identical product	i. Antioxidant Ascorbic acid from fruitii. Tocopherol from vegetable oiliii. Food color carotenoid
Additives obtained by modification of natural substances.	i. Emulsifier from edible oilsii. Thickening agent as modified starch, modified celluloseiii. Sweetener as sorbitol
Man-made product	i. Antioxidant like BHAii. Color like Quinoline yellowiii. Sweetener like saccharin

      Risk assessment of any new food additives is carried out by autonomous international committee JECFA (Joint FAO/WHO Expert Committee on Food Additives). The committee assesses the health risk of additives on human being since 1956. The committee gives approval to only those additives that are found having no appreciable health risk to consumer. National authorities on the basis of JECFA assessment or national assessment approve the level of additives for a particular food. To use a new food additive in the processed food, the manufacturer needs to get its approval from national or international authorities. For that purpose, they need to file a petition to FDA for approval. The petition includes proper evidence that the substance is safe for they ways it is used. To approve the new additives under European Union, the procedure has four parts as follows:

       a. Chemistry and specification of the additive: The additive is identified as per their origin, as a single, complex mixture, derivative of plant source, or synthesized material.

       b. Existing authorization and approval: It is found that whether the additive already exists and what are the previous data of the additive.

       c. Proposed use and exposure assessment: Estimation of dietary exposure based on proposed use and proposed age level of the person.

       d. Toxicological study: Toxicological study regarding the effect of additive on the basis of in vitro and in vivo.

      After approval of the new additive, the FDA issues regulation for the additive that includes the type of food in which it can be used, the maximum amount it can be used, and how it should be mentioned on food labels.

2.2 Merits and Demerits of Food Additives and Preservatives

      2.2.1 Merits of Food Additives and Preservatives

       i. Some additives are added to improve or maintain the nutritive value of food. For example, iodine is added in salt to improve its nutritional value. Enrichment of cereal products with B vitamin is another example of it [2].

       ii. Additives are added to preserve food and without which the food would be spoiled at accelerated rate. Addition of food additives and preservatives reduces the amount of food waste and incidence of food poisoning e.g., additives are added in bread so it does not arrive mouldy when it arrives at grocery store.

       iii. Addition of natural and synthetic color and flavor improves the appearance of the product.

       iv. Additives can change the texture; mouth feel and sensory properties of food products.

       v. Food can make the food processing easier, e.g., chemical defoamer can minimize the foaming in foods having high fat content.

      2.2.2 Demerits of Food Additives and Preservatives

       i. Some additives and preservatives have allergic reaction. For example, artificial color Red 40, Yellow 5, and preservative like benzoate can cause allergic reaction.

       ii. Some of the food additives and preservatives have potential link to cancer. For example, artificial sweetener aspartame has potential to cancer development when applied on rat. Butylated hydroxy anisole (BHA) is used as antioxidant but it was found to cause cancer in animal study.

       iii. They can replace the real ingredient present in the original food. For example, a chicken soup may contain little amount of chicken and the flavor can be managed with the addition of monosodium glutamate.

       iv. Presence of food additives like corn syrup in the processed food may cause obesity and diabetes [3–5].

2.3 Types of Food Additives and Preservatives

Food additives and preservatives can be classified in various ways. Sometimes, it is possible that there might be an overlap between these groups [6]. They can be broadly divided into groups as follows (see also Figure 2.1):

       1. Preservatives

       2. Nutritional Additives

       3. Flavoring Agent

       4. Coloring Agent

       5. Texturizing Agent

       6. Miscellaneous Additives [7]

Figure 2.1 Types of food additives.

      2.3.1 Preservatives

The food additives under this category are used for the preservation of the food. Food may be easily spoiled by the microorganism or by chemical or enzymatic reaction. The addition of preservative may inhibit the growth of spoilage microorganism or they may inhibit chemical and enzymatic reactions. The food preservatives may be of following three types.

       i. Antimicrobials: These additives are added for their ability to inhibit the growth of microorganism. Common additives include benzoates, sorbate, acetic acid, nitrate and nitrites, sulfur dioxide, antibiotics, and phosphates. The overall mode of action of these antimicrobial compounds includes reduced water availability and increased acidity. Natural antimicrobials have the dual benefit that they can inhibit the microorganism as well as make the food safe for eat. They may be derived from microorganism or animal or plant source. Some examples of natural alternative of food preservative include Natamycin, which is an antibiotic selectively that inhibits mold but the growth of bacteria required for ripening of cheese. Nisin and Pediocin are bacteriocin produced by microorganism that is effective on other microorganism. Lysozyme, enzyme lactoperoxidase, and lactoferrin are examples of antimicrobial derived from animal source. Antimicrobial extracted from plant source includes essential oils.

       ii. Antioxidants: Antioxidants are additives that are added in to the food to prevent the oxidation reaction. In food material, two types of oxidation reaction may occur: a. enzymatic oxidation of fruits and vegetables; and b. oxidation and rancidity of fats and oils. Antioxidants used in the food material are of following five types:a. radical scavenger or chain breaking antioxidant that is primary antioxidant and it binds with the free radical formed during oxidation reaction, thus preventing