GB 2760-96: can be used for all types of food; take GMP as the limitation.
FAO/WHO(1984, g/kg): Cream cheese 5; cooked ham, cooked pig forelegs, according to GMT; cottage cheese 5 (by cream); cream 5 (only used for Pasteurized whipped cream or whipped cream with ultra-high temperature sterilization cream and sterile cream).
During the manufacturing of ice cream, gelatin can be used as a protective colloid to prevent the ice crystal from increasing, making the product taste fine, need to be added of about 0.5%. Yogurt, cheese and other dairy products needs to be added of about 0.25%, being able to prevent precipitation of water and enabling the fine texture.
In the manufacture of gelatin dessert (dessert, the main ingredient is gelatin), candy, candy, protein sugar, chocolate, etc. (add 1% to 3.5%, up to 12%).
It is widely applied of gelatin in the luncheon meat, corned beef and other canned food so that the gravy water can be combined to maintain the product shape, humidity and flavor; add about 1% to 5% the weight of meat.
It can also be used as a thickening of soy sauce.
Industrial gelatin appears as colorless or light yellow transparent or translucent flakes or powder. It is tasteless and odorless. It will absorb water for swelling in cold water. It can be dissolved in hot water, being soluble in glycerol and acetic acid, but insoluble in ethanol and ether.
There are mainly lime cream method, hydrochloric acid method and enzymatic method. 1. Lime cream method; cut off the inner layer grease of the degenerated foot skin of cowhide and pigskin and cut into small pieces, place in the 3.5%-4.0% lime cream for soaking of about 30-40d during which the lime cream is changed for 4-6 times. During the soaking process, stir uniformly. The soaked raw hides are taken out from the lime cream tank and washed clean with water; neutralized with 10% hydrochloric acid for 3-4 h under stirring, and the pH should be 6.0-6.5 after washing. And then the pork skin was added into water at a 1: 1 ratio and heated and cooked with the temperature being controlled at 60-70 ℃. Extract the glue water at regular intervals and filter with clean gauze while hot; repeat the above process for a total of 5-6 times. The thin glue water is further sent into the evaporator for concentration to make a relative density of 1.03-1.07. The hot glue is further transferred into the aluminum plate for cooling. The cold plastic is put into the stainless screen and further sent into the drying room for blast drying with the temperature strictly controlled at around 28 ℃.
The dried film is crushed to obtain the finished product. The yield was about 22% by weight of the pig skin. 2. Hydrochloric acid method: the miscellaneous bone, spine and small bone are crushed; use benzene to extract the oil in the 45-50 ° C before washing with water. The washed bone is soaked with 3.5-4.0% hydrochloric acid. After the main bone becomes soft, we can obtain the crude ossein, wash with water so that the pH of the aqueous solution is around 3.5. Addition of lime cream can enable the manufacturing of calcium hydrogen phosphate and dry calcium chloride. The bones is further subject to soaking with over 3.0%-3.5% lime cream for 30-50d (during this time, change the lime cream for 5-6 times). Take it out and wash with water for about 1h. The clean ossein at this time is subject to neutralization with 0.2 hydrochloric acid hydrochloride for the first time. When the pH is dropped to 3.5-4.0, let the neutralization solution go. Add clean water and then neutralize with 0.5% hydrochloric acid for about 2h. When the acid concentration decreased to 0.2-0.25%, the acid concentration is immediately increased to 1% and the concentration was maintained until the neutralization end point (pH 3.0) was reached.
After the completion of the neutralization, the ossein is fully washed with water and soaked for 4-5h. Then wash with sodium hydroxide solution and add dilute alkaline solution for soaking of 16-20h before rinsing with water. At this stage, we can obtain refined ossein. After 7 days of degelatinization of the refined ossein, the glue is obtained. The water amount and temperature of each channel should be controlled separately with the water amount being reduced along with the channel and the gel temperature increased by the road, from 64 ℃ at the first channel to 85 ℃ at the 7th channel. The concentration of the glue from the first to the seventh also decreases from 8% to 2-3%. The whole process of degelatinization lasts for about 40h. The obtained thin glue water is filtered and concentrated to a density of 1.025-1.075. It is then frozen on the plastic box, sliced and placed on the screen, and further sent to the drying room for air drying with the temperature being gradually raised from 25 ℃ to 60 ℃. The finished product is obtained after the dryness. The quality of the gelatin in different channels was different. According to the road, it is divided into camera glue, edible glue, and finally the baking glue for making peptone. The rate of good glue is higher than 60%. Per ton of product consumption: about 7t of bone; about 7 t of 30% hydrochloric acid.
The Chang Yuanming gelatin factory (Ding Chen district in Changde City) applies the chromium leather corner scrap (blue alum skin) during the leather production for production of gelatin. The process is as follows: blue alum skin → broken → liming → leaching → leaching → leaching → Extraction → concentration → dripping → drying → crushing. Consumption of raw material (kg/t): blue alum skin 4000 sulfuric acid (98%) 1000 hydrochloric acid (31%), 200 lime 1000. (3) enzymatic hydrolysis; use protease to hydrolyze the collagen into gelatin; add dilute hydrochloric acid to dissolve it, and then use the acetone, sodium sulfate and sodium chloride to precipitate the gelatin out. This method is not yet mature with the current production shortening the soaking time. The detailed process: the degreasing raw material is washed with NaOH solution (pH = 11~12) for 24 hour; then subject to enzymatic hydrolysis with 2907 alkaline protease at 40 ℃ for 6 h. After water washing, use acid for soaking (PH = 2~2.5) 1 day; wash to a pH of 5.8~6.0, then apply gray soaking for another 3~10 d.
Finishing and degreasing of raw material; have the different varieties of raw materials subject to sorting and selection. The finished skin raw materials is soaked in 1% lime water for dipping of 1-2h, and then cut into pieces and added into the dewatering machine to obtain the degreased broken skin.
Skin [classification; degreasing; maceration] → softened skin [lime water] → debris [hydraulic degreasing] → degreasing broken skin
Dipping, washing; the degreased broken skin is soaked with 2%-4% lime water with the ratio of wet skin and water of 1: 3-1: 4 and pH of 12-12.5. The optimal temperature is 15 ℃ and the time should be around 15-90 days. The impregnated raw material was thoroughly washed with water and stirred continuously. During the initial 5h, change the water every 0.5h once; then change to: 1h interval. The ratio of raw material to water should not be less than 1: 5 with the total time being around 12-16h and the final pH being 9-9.5. Use 6 mol/L hydrochloric acid to neutralize the rest lime so that the pH is around 2.5-3.5. At the range of 1-3 h, adjust the pH value once every 0.5 h; At the rang of 3-8h, adjust the pH value once every 1h; stop adjusting the pH value after 8h; The whole neutralization process should take 12-16h. After the neutralization, remove the acid and wash with water for not less than 8 times and complete the process with 8-12h.
Degreased broken skin [Lime water,> 15 days] → [pH12, 15 ℃] debris after dipping [water, HCl] → [pH2.5-3.5] → glue raw material.
Finishing and concentration; first add heating water into the degelatinize pot, further supply raw materials and avoid forming lumps. Slowly heat to a temperature of 50-60 ℃ so that the water can immerse the raw materials thoroughly. After 3-8 h, give off the glue and then add hot water with the temperature being adjusted to 65-75 ℃ and continue the process. Repeat the above process for several times with the temperature being gradually increased and finally up to boiling. Take the dilute glue solution of about 60 ℃, add activated carbon or diatomaceous earth as filter aid, apply plate-and-frame filter press for filtering to obtain the clarified glue solution, and then centrifuge to degrease, apply vacuum concentration at a temperature of 65 ℃. And finally concentrated to a specific gravity of 1.05-1.08 (50 ℃), containing 23%-33% glue.
Preparation of glue raw material [hot water] → [50-60 ℃; after boiling] dilute gelatin liquid [concentration] → [60-65 ℃] concentrated gelatin.
Gelatinization and drying; the concentrated gelatin solution is added while hot of hydrogen peroxide or sulfurous acid for anti-corrosion or bleaching, and then poured into the metal plate or the model to be cooled to generate jelly so far. The jelly is cut into appropriate pieces or pieces and dried with cold and hot air to its water content of 10%-12% and crushed to obtain the finished product.
Concentrated gelatin solution [gel] → jelly [cut rubber, dry] → finished product.
1. It can be applied to printing and dyeing and other industries
2. As a thickening agent, China provided that it can be used for all types of food with appropriate application according to production needs. It can also be used as the clarification agent of alcohol and hydrophobic colloidal stabilizer.
3. It is a kind of hydrophilic colloid with protective colloid effect. It can be used as a hydrophobic colloid stabilizer, emulsifier. It is also a kind of amphoteric electrolyte and can be condensed into pieces of charged particles, which can be used as the clarifier of wine and alcohol. As a dispersant, binder, thickener, stabilizer and emulsifier, it is widely used in photosensitive materials, pharmaceuticals, food, paper, printing, textile, printing and dyeing, electroplating, cosmetics, bacterial culture and pesticide.
4. It can be used as the protective colloid during turbidity or colorimetric determination; also used for the preparation of photographic plate and medium.
5. It can be used as the food quality improver
6. Thickeners; stabilizers; clarifying agents; blowing agents.
7. Gelatin is a hydrophilic colloid with the nature of protecting colloid. It can be used as a hydrophobic colloid stabilizer, emulsifier. But also as the amphoteric electrolyte, it can be enable the condensation of the charged particles into pieces in the aqueous solution; it can be used as wine, alcohol clarifier.
8. It can be used as excipient suspensions, and media.
9. According to the functional properties of gelatin, its application can be divided into two categories. Class I: taking its colloidal protective capacity as a dispersant for the production of PVC, photographic materials, bacterial culture and pharmaceutical, food (such as candy, ice cream, cod liver oil capsules, etc.). Class II: application of its adhesive capacity as adhesive for being applied to paper, printing, textile, printing and electroplating and other industrial sectors. According to different applications, the quality requirements of gelatin is not the same. Gelatin, when being used as adhesive agent in adhesive tape, paper containers, paper tubes and binding, etc. has the bonding strength be the main value factor; when applied to the fields of photography, food and medicine, people emphasize more on the product purity. The national standard number of edible gelatin in China is GB6783-86; the usage range and maximum allowable amount should be referred to GB2760-86.
ADI doesn’t make restrictive regulations (FAO/WHO, 2001).
As stabilizer, thickener and texturizer in food; manufacture of rubber substitutes, adhesives, cements, lithographic and printing inks, plastic Compounds, artificial silk, photographic plates and films, matches, light filters for mercury lamps; clarifying agent; in hectographic masters; sizing paper and textiles; for inhibiting crystallization in bacteriology, for preparing cultures. Pharmaceutic aid (suspending agent; encapsulating agent; tablet binder; tablet and coating agent).
Standard for Maximum Allowable Amount
|Name of additive
||Food allowed to use it as additive
||Function of additive
||Maximal allowable amount（g/kg）
||Maximal allowable residue（g/kg）
||Use proper amount according to the demand of the production (except in case where special rule is provided)
||Use proper amount according to the demand of the production (except in case where special rule is provided)
white to slightly yellow powder, also knownas glutin,is a protein found in many animal tissues including skin, cartilage, horn, and bone. Gelatin is used in leather dressings, in photography, in metallurgy, in the plastics industry, and in pharmaceuticals.