Royal Jelly is also called Bee Milk. The fresh royal jelly is slightly ropy milk paste substance; it is the excretive mixture of nutrition gland and maxilla gland of the head of little worker bee. The worker bees use this to feed the 1-3 days` worker bee larva and drone larva, 1-5.5 days` queen bee larva and queen bee in the oviposition period. The royal jelly is the biologic product containing very complicated active elements which contains almost all the nutrition elements required by the growth of the human body. Royal Jelly Royal Jelly,Natural Royal Jelly,Healthy Royal Jelly,Organic Fresh Royal Jelly Easy Food (Jiaxing) Co., Ltd. , http://www.jxeasyfood.com
First, the production process shrimp shell - pretreatment - digestion - acid leaching - decolorization - drying - deacetylation - drying - products
Second, the main process and parameters (a) raw material pre-digestion must be shrimp shell meat, dirt and other impurities removed, washed with water; raw materials are not processed in the short term, after sun drying after storage.
(B) Digestion
1. Purpose: To remove protein and fat from raw materials.
2. Method: Put the pre-treated shrimp shell into a sandwich pot, add 18% to 19% sodium hydroxide solution, and boil for 1.5 hours while stirring.
(c) Acid leaching
1. Purpose: To dissolve and soften the inorganic salt in shrimp shell.
2. Method: Soak the digested shrimp shell in 4% to 6% hydrochloric acid solution until the raw materials are all softened. When no bubbles are produced, the pickling process ends. The time is generally 1 to 2 days. During the soaking process, if the raw material is found not to be soft and there is no bubble generation, it means that the acid amount is insufficient and soaking with acid is required.
(d) Decolorization
1, the sun decolorization: the acid-leaching raw materials rinsed with water to the acidic reaction, the raw materials were spread on the ground, the use of sunlight exposure and constantly turning until the shrimp shell all bleached.
2. Oxidation and decoloration: Oxidative decoloration can also be performed using potassium permanganate, sodium bisulfite, and the like.
(e) Deacetylation The deacetylation process is the key, it is directly related to the quality of the product. Because of the action of concentrated base, chitin, in addition to the deacetylation reaction, also accompanied the degradation of the molecular backbone, resulting in lower molecular weight. The size of the molecular weight and the free amine group content are important indicators of the performance of the reaction chitosan. Generally, the degree of deacetylation is used to reflect the free amine group content, and the viscosity is used to measure the size of the molecular weight. The main process parameters affecting the deacetylation of chitin are alkali concentration, temperature and reaction time.
1. Alkaline concentration: The alkali concentration is generally 40% to 60% and must not be lower than 30%. Alkali concentration below 30%, no matter how high the operating temperature and the length of time, can only remove half of the acetyl in chitin. As the concentration of alkali increases, the deacetylation rate of chitin increases and the degree of deacetylation increases, but the alkali concentration reaches more than 50%, the reaction rate increases slowly, and the main chain hydrolytically breaks easily, the molecular weight decreases, and the product viscosity decreases.
2. Temperature: Temperature is another important factor affecting the degree of deacetylation and viscosity of chitin. As the reaction temperature increases, the deacetylation rate of chitin increases. When the degree of deacetylation reaches 80%, the reaction needs only 15 minutes at 150°C, 3 hours at 120°C, and 16 hours at 80°C. The reaction temperature has a certain influence on the viscosity of chitosan. With the prolongation of reaction time, the viscosity of chitosan decreases regardless of the temperature, and the higher the temperature, the faster the viscosity of chitosan decreases.
3. Time: The reaction time of deacetylation of chitin is related to the reaction temperature and alkali concentration. Under certain conditions of temperature and alkali concentration, the deacetylation rate of initial chitin increases, and as the reaction progresses, deacetylation proceeds. The increase is slowed down, while the viscosity of chitosan continues to drop.
Increasing the reaction temperature, alkali concentration and prolonging the reaction time can increase the degree of deacetylation of chitosan, but the main chain of chitosan is degraded in the alkali liquor and the viscosity of the product is decreased. Generally, the concentration of alkaline solution is controlled at about 50%. High deacetylation degree and high viscosity can be prepared by reducing the deacetylation reaction temperature at about 120°C, shortening the reaction time by 1 hour, increasing the number of reactions, and conducting the dissolution-precipitation treatment of intermediate products. Chitosan.
Third, product quality indicators (a) Appearance: colorless or yellowish translucent solid (b) physical and chemical indicators
1, ash <1%
2, water<12%
3, viscosity> 600 centipoise
4, deacetylation degree> 80%
5. The solubility is completely transparent and viscous liquid within 0.5 hours with 5% acetic acid.
Using lobster shells to produce chitosan
Because chitosan is widely used in many fields such as medicine, textile, printing and dyeing, papermaking, food, wastewater treatment, metal recycling, environmental protection, cosmetics and daily-use chemicals, people are paying increasing attention.