2, grain and oil processing industry mainly includes rice processing, wheat processing, corn processing, soybean processing, oilseed processing, grain processing and potato processing, grain and oil food production, grain and oil by-products comprehensive utilization and the manufacture of related machinery and equipment and testing instruments.
3, China's grain and oil processing industry, the main problems: (1) with the strength to participate in international competition in the serious lack of conglomerate, weak competitive ability; (2) production capacity and utilization rate is low, the start rate is insufficient, restricting the overall development of the industry. Abnormal price fluctuations of raw materials and oilseeds, etc., the deep processing of raw materials is not comprehensive and has no outstanding features, in-depth research is still needed in grain and oil processing technology and grain and oil processing equipment, etc., there is a shortage of domestic raw materials, which is dependent on imports, and the industry's profitability is greatly affected by globalization factors.
4, grain and oil products according to the type of raw material is divided into four types of cereals (rice, wheat), oilseeds (peanuts, rapeseed), beans (soybeans), potatoes (sweet potatoes, potatoes).
5, protein classification: simple proteins and binding proteins. Simple proteins can be divided into clear protein, globulin, gliadin, gluten; binding proteins according to the chemical composition of the cofactor can be divided into nuclear proteins, phosphoproteins, lipoproteins, glycoproteins, chromoproteins.
6, gluten: wheat flour and water into dough, after a period of time, put the dough in the flowing water kneading, the starch grain and bran particles in the dough with the water gradually washed away. Soluble substances are also dissolved by water, and the last remaining piece of soft elastic soft gelatinous material is gluten.
7, the formation of gluten: gluten protein in the dough is not soluble in water, the surface of its spatial structure and the inner layer of the existence of certain polar groups, it is easy to water molecules adsorbed in the surface layer of gluten protein monomers, after a period of time, the water molecules will gradually diffuse penetrate into the molecular interior, resulting in the expansion of the volume of gluten proteins, the gluten protein molecules expanding after the full absorption of water to each other relying on the polarity of the groups and water molecules integrated and interlaced linkage. Water molecules integrated and interlaced together to gradually form a gluten network.
8, gluten characteristics: EQ \o\ac(○,1)1 elasticity: the elasticity of gluten refers to the ability of gluten to return to its original state after stretching or compression;
EQ \o\ac(○,2)2 elongation: elongation refers to the performance of the gluten to a certain length without breaking;
EQ \o\ac(○,3)3 toughness: the resistance of gluten when stretched. resistance it exhibits when stretched;
EQ \o\ac(○,4)4 specific elongation: refers to the length of gluten being stretched per minute, expressed in centimeters.
9, starch is divided into straight chain starch and branched chain starch.
10, the physical properties of starch: starch is a white powder, hygroscopicity is very strong, natural starch granules are insoluble in cold water, but in hot water can absorb water expansion.
11, chemical properties: in general, starch does not show reducing points. Starch meets acid *** cooking, that is, the line of water absorption, and finally all decomposed into glucose.
12, enzyme and acid method to determine the principle of starch content: starch can be hydrolyzed by amylase, and then by the role of acid and finally all hydrolyzed into glucose. This determination of glucose production can be converted to starch content.
13, starch and iodine reaction: straight-chain starch meets iodine that is generated a dark blue complex or complex, and branched-chain starch meets iodine is reddish-purple, and does not produce coordination structure.
14, starch pasting: starch in the ordered and disordered state of the starch molecules between the hydrogen bond broken, dispersed in water into a hydrophilic colloidal solution.
15, starch regeneration: is the paste of starch molecules and automatically arranged into order, and by the hydrogen bond combined into a bundle structure, so that the solubility is reduced.
16, the chemical composition of fats and oils is fatty acid triglycerides. Fats and oils can be divided into saturated fatty acids and unsaturated fatty acids.
17, the melting point of triglycerides increases with the length of the carbon chains that make up the fatty acid.
18, EQ \o\ac(○,1)1 fatty acid valence: the mass of potassium hydroxide (expressed in mg) necessary to neutralize all the free fatty acids in 1g of fat is known as the acid price. The higher the acid price, the worse the quality.
EQ \o\ac(○,2)2 Iodine valence: the mass of iodine (expressed in g) necessary to bind to 100g of fat is called the iodine valence of that fat. The lower the iodine valence, the lower the content of unsaturated fatty acids, and the higher the iodine valence, the more easily the fat oxidizes.
EQ \o\ac(○,3)3 Saponification valence: is the mass of potassium hydroxide (expressed in mg) required to neutralize the free fatty acids in 1g of fat, and also to neutralize the fatty acids that are glycerolized. The amount of fatty acids that are glycerolized can be determined by the ester value. The ester value is the difference between the saponification price and the acid price of the fat.
19, amylase can be divided into -amylase, -amylase, glucoamylase, isoamylase and so on according to different mechanisms of action.
20, wheat flouring is the wheat through shear, extrusion and other mechanical forces will be separated from the wheat skin and endosperm, endosperm grinding into powder, after sieving to obtain a certain number and proportion of flour in line with the national quality standards.