Food additives are an important factor in the modern food industry, playing an extremely important role in improving the color, aroma, and taste of food, increasing food nutrition, improving food quality, improving processing conditions, preventing food spoilage, and extending food shelf life. Therefore, the food additive industry occupies an important position in the modern food industry.
01 Definition and Function of Food Additives
1. The definition of food additives refers to artificially synthesized or natural substances added to food to improve its quality, color, aroma, and taste, as well as to meet the needs of preservation and processing technology. 2. The functions and development trends of food additives 1) The main functions of food additives a) can improve the quality of food, enhance its quality, and meet people's requirements for food flavor, color, and taste; b) It can make food processing and manufacturing processes more reasonable, hygienic, and convenient, which is conducive to the mechanization, automation, and scaling of the food industry; c) It can save resources and reduce costs in the food industry, greatly improve food quality and grade, increase its added value, and generate significant economic and social benefits. 2) The development trend of food additives a) Developing natural, nutritious, and multifunctional food additives; b) Dedicated to developing diverse and specialized additives. 02 Types of Food Additives
Food additives can be divided into natural food additives and artificially synthesized food additives according to their sources. Classified by function, it mainly includes: nutrition enhancer, antiseptic and mildew inhibitor, antioxidant and fresh-keeping agent, thickener, emulsifier, chelating agent (including stabilizer and coagulant), quality improver, flavoring agent, color treatment agent, edible essence, spices, etc. 1. Food preservatives are a type of additive used to inhibit food spoilage and spoilage, extend storage and preservation periods. Currently, there are four main types of food preservatives commonly used: benzoic acid and its salts, sorbic acid and its salts, propionic acid and its salts, and p-hydroxybenzoate esters. 1) Benzoic acid and its sodium salts, also known as benzoic acid, are commonly used organic fungicides. In low pH environments, benzoic acid is effective against a wide range of microorganisms, but its effect on acid producing bacteria is weak. When the pH is above 5.5, it has no effect on many fungi and yeast. The optimal pH value for benzoic acid inhibition is 2.5-4, and the minimum mass fraction for complete inhibition of general microorganisms is 0.05% to 0.1%. 2) Sorbic acid and its salts. Sorbic acid, also known as 2,4-hexadienoic acid, is a broad-spectrum food preservative. 3) Propionic acid and its salts Propionic acid is a liquid with a stimulating acid aroma similar to acetic acid. As it is a normal intermediate in human metabolism, it is non-toxic and its ADI value is not limited. Propionic acid is effective against mold, aerobic bacteria, Gram negative bacteria, especially against Escherichia coli, which produces filamentous mucus in bread, and can prevent the production of aflatoxin. Therefore, it is commonly used in the production of bread and pastries. Propionate salts have the same anti-corrosion effect, with calcium and sodium salts commonly used. 4) Hydroxybenzoic acid and its esters, also known as Nipagin esters, are colorless crystalline or white crystalline powders, odorless and odorless. Mainly used for soy sauce, jam, refreshing beverages, etc. The anti-corrosion effect is better than benzoic acid and its sodium salts, with a usage amount of about 1/10 of sodium benzoate and an appropriate pH value of 4-8. The toxicity of hydroxybenzoate is lower than that of benzoic acid, and its water solubility is poor. Commonly used alcohols are dissolved before use, and the price is also high. 5) Natural food preservatives have the advantages of strong antibacterial activity, safety and non toxicity, good water solubility, good thermal stability, and wide range of action. They are not only harmless to human health, but also have certain nutritional value. In recent years, natural preservatives researched and developed include natamycin, glucose oxidase, protamine, lysozyme, polylysine, chitosan, pectin decomposition products, propolis, tea polyphenols, etc. 2. Food emulsifiers and thickeners are additives that improve and stabilize the physical properties of food components or improve the tissue state of food. They play an important role in the shape, quality, and processing performance of food. 1) Emulsifiers are food additives that can form stable emulsions of immiscible liquids (such as oil and water) by adding a small amount. ① Fatty acid glycerides
Glycerol reacts with fatty acids to produce mono, di, and tri esters. Monofatty acid glyceride, referred to as monoglyceride, is an important food emulsifier, which is widely used in shortening, cakes, bread, candy and ice cream, and has the functions of emulsification, foaming, crystallization prevention and anti-aging. ② Sucrose fatty acid ester
Sucrose fatty acid ester is a high-performance, efficient, and safe emulsifier. Sucrose fatty acid esters have sucrose as a hydrophilic group and long-chain fatty acid as an oleophilic group, which can be digested into sucrose and fatty acids in the body and absorbed. Sucrose fatty acid esters are non-toxic, non irritating, and easily biodegradable, so their use in food is not restricted. ③ Dehydrated sorbitol fatty acid ester
The commercial name of dehydrated sorbitol fatty acid esters is span, and span type emulsifiers react with ethylene oxide under alkaline catalysis to obtain Tween type emulsifiers. ④ Soy phospholipids
Soy phospholipids, also known as soy lecithin or phospholipids, are a light yellow or brown transparent, semi transparent viscous substance. He is a by-product of soybean oil production and a natural surfactant. Its main components are lecithin, cephalin, and inositol phospholipids. Soybean phospholipids, as emulsifiers, have excellent emulsifying, antioxidant, dispersing, and moisturizing properties, and have been widely used in food, instant milk, artificial cream, granular beverages, nutritional emulsifiers, and other fields. 2) Thickener is a type of food additive that can increase the viscosity of food and change its performance. ① Gelatin
Gelatin is a white or light yellow, semi transparent, slightly glossy thin or fine particle, mainly composed of protein. It is a high molecular weight peptide polymer obtained by partial hydrolysis of collagen protein contained in animal skin, bone, cartilage, etc. Gelatin gel is tough, elastic, and has good pressure bearing property. It is dissolved in water at 30 ℃ and coagulated after cooling. ② Maltodextrin
Maltodextrin, also known as water-soluble dextrin or enzymatic dextrin, is made from various types of starch as raw materials, and is hydrolyzed, purified, and dried through enzymatic processes with low degree control. Maltodextrin is widely used in candy, malt extract, fruit tea, milk powder, ice cream, beverages, canned goods, and other foods as a filler and thickener for various foods. ③ Pectin
Pectin is a polysaccharide substance widely present in plant tissues, mainly composed of galacturonic acid. It is recommended by the FAO/WHO Joint Committee on Food Additives and is recognized as a safe food additive without limit on dosage. At present, the main raw material for producing pectin is citrus peel. ④ Carrageenan
Carrageenan is a natural plant gum extracted from red algae, and is the youngest of the three major seaweed gums: brown algal gum, agarose, and carrageenan. Its main components are D-galactose and L-galactose. Carrageenan is extracted from raw materials such as eucalyptus, seaweed, and carrageenan. Carrageenan used in the food industry mainly has the characteristics of gel, viscosity, stability, emulsification and suspension, and is widely used in dairy products, ice cream, juice drinks, bread, hydrogel (see gel, etc.), meat products, cans and other foods. ⑤ Xanthan gum
Xanthan gum is a safe, non-toxic, and odorless new type of food additive, with excellent thickening, suspension, emulsification, stability and other functions. Xanthan gum is an extracellular polysaccharide produced by Aspergillus flavus using starch as the main raw material through a series of biochemical reactions. Its main components are glucose, mannose, glucuronic acid, etc., with a molecular weight of millions. It is currently the most commercially valuable, largest in production, and widest in market coverage among microbial polysaccharide products at home and abroad. Xanthan gum has excellent thickening properties and can achieve the required viscosity at very low concentrations. Xanthan gum can form a stable thickening system when coexisting with high concentrations of sugars or various salts. 3. Seasoning agents: Seasoning agents mainly include sourness, sweetness, saltiness, and bitterness. Bitterness agents are rarely used, while saltiness agents (usually salt) are not managed as food additives in China. The following mainly introduces sourness and sweetness agents. 1) A food additive with the main purpose of imparting sourness to food is called a sourness agent. Sour taste can promote the secretion of digestive juices such as saliva, gastric juice, and bile, and has the functions of promoting appetite and aiding digestion. Its main functions include regulating the pH value of food, acting as an antioxidant enhancer, preventing food from becoming rancid or browning, inhibiting microbial growth, and preventing food spoilage. Sour agents mainly include organic acids such as citric acid, lactic acid, tartaric acid, malic acid, fumaric acid, and adipic acid; Inorganic acids: edible phosphoric acid, carbonic acid, etc. ① Citric acid
Citric acid is colorless transparent crystal or white powder with mild and refreshing sour taste. It is widely used in the manufacture of various drinks, soda, wine, candy, Dim sum, biscuits, canned fruit juice, dairy products and other foods. ② Malic acid
Malic acid, also known as carboxylsuccinic acid or hydroxysuccinic acid, is a white or fluorescent solid. He has a special malic acid aroma and is widely used in yogurt, soda, ice cream, chewing gum, tomato sauce, jam, vinegar, fruit wine, margarine, etc. Malic acid has a better effect than citric acid, a strong sour taste, a taste similar to natural fruit juice, and a good pH regulation effect. Using it as a substitute for citric acid as an acid flavoring agent can save 20% in dosage and mask the odor produced by some sucrose substitutes. 2) Sweeteners are food additives primarily designed to impart sweetness to food. According to their sources, they can be divided into two categories: natural sweeteners and synthetic sweeteners. Natural sweeteners are divided into two categories: sugars and their derivatives, and non sugar natural sweeteners. Artificial sweeteners are mainly chemical substances with a sweet taste, and their sweetness is generally tens to hundreds of times higher than sucrose, and most of them do not have nutritional value. ① Saccharin and Saccharin Sodium
The chemical name of saccharin is ortho sulfonylbenzimide, which has no calories and high sweetness. Sodium saccharin has a sweetness 300-500 times that of sucrose and is an early developed chemically synthesized sweetener. It has been applied in food since the beginning of the 20th century. China has a history of production and use for more than 60 years, with a production capacity of 40000 tons per year, making it a major exporter in the world. ② Xylitol
Xylitol is a sugar alcohol produced by reducing xylose or polyxylose in materials such as wood and corn cobs. Xylitol is a white crystalline or crystalline powder with a cool and sweet taste. Its sweetness is 65% to 100% of that of sugar, and its calorific value is 12.5 kJ/g. It is higher than other sugar alcohols and has the effect of inhibiting the activity of Proteus, which forms dental caries. Xylitol not only has the common properties of sucrose and glucose, but also has special biochemical properties. It can be absorbed by the human body through the cell wall without the need for insulin, and has functions such as reducing blood lipids and anti ketosis. It can be used to make beverages, candies, canned foods, and other foods. ③ Steviol glycoside
Steviol glycoside is a colorless or pale yellow needle shaped crystal with a melting point of 196-198 ℃. It is a mixture of multiple glycosides extracted from plant stevia and is relatively safe. Its sweetness is about 300 times that of sugar. Its taste is similar to sucrose, with a pure sweetness, long retention time, and a delicious aftertaste. It is stable to heat, acid, and alkali, making it an ideal low-energy sweetener. ④ Malitol
The sweetness of maltitol is 0.8-0.9 times that of sucrose, and it does not produce calories, synthesize fat, or stimulate the formation of cholesterol after intake. The chemical properties of pure maltitol are very stable, with better heat and acid resistance than sucrose, sorbitol, and xylitol. Malitol can resist the digestion of gastric juice, hydrolysis of small intestine enzymes, and decomposition of large intestine microorganisms during human digestion. This special physiological performance makes maltitol a high-end health sweetener with excellent taste and no calories. ⑤ Aspartame
The chemical name is aspartate phenylalanine methyl ester, with a relative molecular weight of 294.31. Aspartame is a new type of amino acid sweetener with a white crystal or crystalline powder appearance, pH: 4.5-6.0. Aspartame has a pure sweet taste similar to sugar, with a sweetness 200 times that of sucrose. It has no odor and has a synergistic effect on food flavor. Good safety performance, metabolism in the body does not require insulin participation, can be quickly digested and absorbed, and will not cause dental caries. ⑥ Ansemi
The chemical name is potassium acetylsulfonamide, with a molecular weight of 201.24. Ansemi is a white crystalline powder with high sweetness, which is about 200 times that of sucrose (3% mass fraction solution). ⑦ Other sweeteners
There are mainly oligofructose, erythritol, saccharin, sorbitol, etc. 4. The additive used for coloring food is called food coloring, which aims to increase appetite and stimulate appetite. Food pigments can be divided into two categories based on their sources: artificially synthesized pigments and natural pigments. 1) Artificial synthetic pigments include amaranth red, carmine red, erythrin red, new red, lemon yellow, sunset yellow, indigo yellow, bright blue, as well as aluminum lakes of various pigments that enhance the dispersibility of water-soluble acidic pigments in oils and fats. ① Carmine red
Carmine is a red to deep red powder. Its characteristics are good acid and light resistance, but poor heat and reduction resistance, turning brown when exposed to alkali. It is mainly used for pastries, beverages, and processing of agricultural, livestock, and aquatic products. ② Lemon yellow
Lemon yellow is an orange yellow powder that is widely used in various countries. It is mainly used in pastries, beverages, processing of agricultural, livestock, and aquatic products, medicine, and cosmetics. Its characteristics are good heat resistance, acid resistance, light resistance, and salt resistance, poor oxidation resistance, slightly turning red when exposed to alkali, and fading when reduced. 2) Natural pigments are extracted from plant tissues using solvents. Although natural pigments have a slightly inferior color and relatively poor stability to light, heat, pH, etc., their safety is higher than that of artificially synthesized pigments, and they are abundant in sources. Some natural pigments also have Vitamin activity or some pharmacological functions, which are increasingly valued by people, and their production and sales have grown rapidly. The main products of edible natural pigments in China include caramel, red koji rice and red koji Rice noodles, red koji red, chilli oleoresin and chilli red, Mast yellow, Mast blue, beet red, shellac red, etc. 03 General requirements and safe use of food additives
With the development of food toxicology, it has been discovered in recent years that food additives that were previously considered harmless may have chronic toxicity, teratogenicity, mutagenicity, and carcinogenicity. Therefore, countries have given full attention to this issue. At present, both internationally and domestically, there is a strict management, strengthened evaluation, and restricted use attitude towards food additives. To ensure the safety of food additives, they should follow the following principles: ① Safety evaluation. The primary criterion for evaluating the toxicity (or safety) of food additives is the ADI value (daily human intake), and the second commonly used indicator for evaluating the safety of food additives is the LD50 value (median lethal dose, also known as median lethal dose). ② Usage regulations. GB2760-2014 National Food Safety Standards and Food Additive Use Standards stipulate the principles of use of food additives, the types of food additives allowed to be used, the scope of use, and the maximum amount of use or residue.
January 26, 2024