Knowledge of the use of colorants, color protectors and bleaches
Colorants
Color and luster are important sensory indicators for evaluating the quality of food;
Whether the color is normal or not is an important basis for judging the quality of food;
Foods with pleasing color and luster can win a good first impression.
Colorant is to make the food color and improve the color of food substances.
I. Food and Color
The color of food and its acceptability.
It is the first feeling
It is one of the indicators to judge whether the quality of food is good or bad freshness
The value of food ingredients is determined by their color and luster
However, in food processing, the natural pigments in food will be discolored or faded, so in order to restore or improve the color of food, it is necessary to use coloring agents.
Color and luster give flavor associations. The ability of a food product to be attractive and give a sense of taste in terms of color largely determines the marketability and evaluation. Common colors act on the senses in the following general ways:
Green and blue: give a person a fresh, refreshing feeling, mostly used in alcohol, convenience dishes, beverages and other foods. But there is a raw, cool, sour feeling, so non-vegetable canned food, snacks and pastries, etc. generally do not use these colors.
Red: give people a strong taste of mature and delicious feeling, and more bright and eye-catching, can stimulate the consumer’s desire to buy, so many candies, pastries, etc. are used in this type of color.
Orange: is a mixture of yellow and red color, both red and yellow advantages of the two colors, giving a strong sense of sweetness, maturity and mellowness, beverages and canned food and other foods are used.
Coffee color: it gives a feeling of unique and strong flavor. Coffee, chocolate, beverages, pastries, beer and tea are often used.
Yellow: gives a person the feeling of aroma, ripe and delicious, appetite, baked goods, canned fruits and margarine and other foods are often used.
Second, coloring agent classification
(A) food synthetic coloring
Food synthetic coloring is an artificial chemical synthesis of organic pigments. At present, the world allows the use of synthetic pigments are almost exclusively water-soluble pigments, in addition to their respective color precipitates.
Color precipitation is by water-soluble pigments precipitated in the permitted use of insoluble substrate (usually Al2O3) prepared by the special coloring agent, suitable for a variety of powdered foods, snack foods, gummies, candies (especially with titanium dioxide formulated as a suspension of coated or sliced confectionery) and a variety of pressed food.
China’s permitted use of synthetic food coloring are: amaranth red, carmine, erythrosine, new red, seductive red, lemon yellow, sunset yellow, bright blue, indigo and their respective aluminum precipitates, as well as β-carotene, sodium copper chlorophyll and titanium dioxide.
(ii) Edible natural colors
Edible natural pigments are from natural substances, the use of certain processing methods to obtain organic coloring agents, there are many varieties.
Plant pigments: such as green (chlorophyll), orange (carotene), red or purple (anthocyanin);
Animal pigments: e.g. red pigments in muscle, carotenoids in shrimp and crab skin;
Microbial pigments: e.g. erythroxanthin.
Advantages: security than synthetic pigments, so the recent development is rapid, countries licensed to use the varieties and the amount are increasing.
Disadvantages: pigment content and stability are not as good as synthetic products.
Development trend: Although the use of synthetic products in the permitted range and the amount of use, will not bring harm to human health, but in the reverence for natural and return to nature today, the use of chemicals is declining year by year, and natural coloring agents are becoming more and more popular.
Third, the use of colorants
(I) Blending
Because of the varied requirements of food on the tone, so in order to meet the coloring needs of food production, colorants can be mixed in different proportions to blend the desired tone. Theoretically, the three basic colors of red, yellow and blue (ternary colors) can be blended to produce a variety of different shades (three-color principle).
Precautions when mixing colorants:
When coloring, do not use colorant powder directly, but use solvents to formulate (the main consideration is its uniform distribution in the food).
When preparing, weigh accurately, dissolve the colorant, and then dilute it to a solution of 1~10% concentration for use. If water is used as the solvent, distilled or deionized water is preferred.
Prepare the solution without metal utensils as far as possible. Do not use more than the standard amount, so as not to avoid the food too brightly colored and unnatural.
Use as you prepare. Because the coloring solution is left for a long time, the light is not stable enough coloring agent will occur discoloration phenomenon, and higher temperatures when the coloring agent solution water evaporation speed up, resulting in increased pigment concentration and produce a “concentration effect”. Such as carmine aqueous solution will become black after long-term placement.
(B) solvent and solubility
In food production, the most important solvents are water, alcohol (ethanol, glycerol) and vegetable oil. The pigments normally used, with the exception of color pigments and β-carotene, are water soluble.
Factors affecting the solubility of pigments are:
1, temperature. General temperature
Translated with DeepL.com (free version)
(I) Blending
Because of the ever-changing requirements of food on the hue, so in order to meet the coloring needs of food production, colorants can be mixed in different proportions to blend the required hue. Theoretically, the three basic colors of red, yellow and blue (ternary colors) can be blended to produce a variety of different shades (three-color principle).
Precautions when mixing colorants:
When coloring, do not use colorant powder directly, but use solvents to formulate (the main consideration is its uniform distribution in the food).
When preparing, weigh accurately, dissolve the colorant, and then dilute it to a solution of 1~10% concentration for use. If water is used as the solvent, distilled or deionized water is preferred.
Prepare the solution without metal utensils as far as possible. Do not use more than the standard amount, so as not to avoid the food too brightly colored and unnatural.
Use as you prepare. Because the coloring solution is left for a long time, the light is not stable enough coloring agent will occur discoloration phenomenon, and higher temperatures when the coloring agent solution water evaporation speed up, resulting in increased pigment concentration and produce a “concentration effect”. Such as carmine aqueous solution will become black after long-term placement.
(B) solvent and solubility
In food production, the most important solvents are water, alcohol (ethanol, glycerol) and vegetable oil. The pigments normally used, with the exception of color pigments and β-carotene, are water soluble.
Factors affecting the solubility of pigments are:
1, temperature. Generally temperature increases, solubility increases;
2, pH. pH decreases, colorants have a tendency to form pigment acids and make the solubility decrease;
3, water hardness. High water hardness tends to produce insoluble color precipitate;
4, salts. When the concentration of salts is high, salt precipitation can occur;
5, the nature of the solvent
