食品科学与技术双语重点.docx

1、食品科学与技术双语重点29. What are the final products of wheat wet milling? What about their uses?-main products: starch, 66%; 湿磨终产物 -by products: oil, 4%; animal feed, 30%, including 24%, gluten feed (PC, 21%) and 5.7% gluten meal (PC, 60%).Uses: -modified starch; -sweeter; -alcohol; -others30. What are the u

2、ses of vital gluten? 活力粉用途-improving the texture and raising the protein content;-forming an extensible, elastic mass;-fortification of week hour;-high protein break making;-high fiber bread making;-others, meat products, e.g. sausages, breakfast food.1.Whats defination of oils and fats? 油脂分类Edible

3、fats and oils are esters of the three carbon trihydric alcohol, glycerin, and various straight chained monocarboxylic acids known as fatty acids.2.whats the major and minor component of edible oils and fats?Triglyceride; 食用油和油脂 主次成分Diglyceride monoglyceride phospholipids sterol cholesterol tocophero

4、l pigments3 What are the major fatty acids of oils and fats? 油脂主要脂肪酸Palmitic oils stearic oils oleic linoleic linolenic4.Classification of oils and fats 油脂分类Saturated monounsaturated polyunsaturated 5.Iodine vaule 碘值he number of centigrams iodine absorbed by 1g of fat or percentage iodine absorbed.

5、6. Saponification value : 皂化值the weight in milligrams of potassium hydroxide needed to completely saponify 1 g of fat.7. Peroxide Value 过氧化值the milliequivalents of iodine formed per kilogram of fat. 8.Acid Value 酸价 The milligrams of potassium hydroxide needed to neutralize the free fatty acids in 1g

6、 of a fat9.Meat fat: 动物油Butterfat 、 Lard 、 Tallow Vegetable fat 植物油Canola Coconut Corn Cottonseed Olive Palm and Palm Kernel Peanut Safflower Soybean Sunflower10. The general guideline for oilseed storage is low moisture, low temperature and aeration.11. Oil Extraction： 油萃取 Seed Preparation Renderin

7、g Pressing Solvent Extraction 12. Degumming： 脱胶Degumming is carried out by adding 2% water to the oil.Remove phosphslipids13 Refining 精炼Refining usually refers to the removal of nonglyceride fatty materials by washing the oils with strongly alkaline water solutionsRemove Free fatty acids.14. Bleachi

8、ng 漂白Bleaching is the process used for the removal of pigments from the oilRemove pigments15.Deodorization 除臭Deodorization is the process whereby the odors and flavors of fats and oils are removed,Remove volatilized gas 16. Fractional Crystallization 分离结晶Winterization冬化 Dewaxing脱蜡 Stearine Separatio

9、n硬脂酸分离17. Hydrogenation:Hydrogenation is the treatment of fats and oils with hydrogen gas in the presence of a catalyst. 加氢18. Interesterification:interesterification is the exchange of acyls of triglycerides of two separate fats or a single fat. 酯化作用19.What are the main protein products? 蛋白质产品Prote

10、in flour; protein concentrates ;protein isolates;texturized protein20.What is defatted soybean protein flour? 脱脂大豆蛋白粉Flour produced by the nearly complete removal of the oil fromsoybeans by the use of hexane or other homologous hydrocarbon solvents.21.How is edible soybean soybean protein flour prod

11、uced? 可食大豆蛋白粉Soybean storagesoybean cleaningsoybean temperingdehullingconditioning and flakingextraction and desolventizingtoastingflour and grit grindingfat-conditioning soybean protein flour 22、Whats the definition of soybean protein concentrates? 大豆集中蛋白soybean protein concentrate is a product hav

12、ing a protein content of 70% (N6.25) on a moisturefree basis.23.How to produce soybean protein concentrates? 大豆浓缩蛋白(1)Extraction with aqueous acids in the isoelectric range of pH 4-5.(2)Extraction with aqueous alcohol.(3)defatted flakes or flour are moist heat treated to denature and thereby insolub

13、ilize the protein.24How to immobilize the major protein fraction in soybean? 固定大豆蛋白a. Leaching with Aqueous Organic Solvents.b. Leaching with Dilute Acid.25.What are soybean protein isolates? 大豆分离蛋白isolated soy proteins must contain not less than 90% dry-basis protein (Nitrogen6.25).26.How many func

14、tional properties do vegetable have?What are they？ 蔬菜功能特性(1)Hydration and Water Absorption (2)Solubility (3)Viscosity and Gelation (4)Texturization (5)Emulsion and Foaming (6)Color, Flavor, and Odor27、How many methods can be used to produced texturized protein? What are they？ 脉络产生蛋白质 Three. Extrusio

15、n ;spinning ; steam texturizing 28.Process for Producing Soybean Protein Isolates 大豆分离蛋白生产工艺The starting material for soy protein isolate is finely ground, defatted flakes that have been desolventized by a vacuum process for maintaining protein solubility. The protein is extracted with dilute alkali

16、, pH 9, at 50-55. Stronger alkali would extract more protein but would also cause more damage particularly to the sulfur-containing amino acids. The solids are separated by screening and centrifuging and contain primarily insoluble carbohydrates and proteins. The soluble protein portion is adjusted

17、to pH 4.5 with food grade acid. This results in a protein precipitate and a whey fraction). The precpitate is washed， neutralized ，sterilized and then dried to yield a soy proteinate. 29.What is the difference between the bulk density and absolute density ?bulk density 相对密度和绝对密度区别Definition: The wei

18、ght of a given volume of grain including the voids is the bulk density of the material. Bulk density is a widely used grain property. It is part of the U.S. grain standards. absolute densityDefinition: The absolute density of the grain is the weight per unit volume of the grain itself, independent o

19、f the voids between the grain. The density of the grain can be determined by an air comparison pycnometer30. What is the angle of repose ? 静止角Definition: When poured on a level surface, grain forms a pile whose outer edge makes an angle to that surface. The value of the angle is specific to the grai

20、n and is called the angle of repose. 31. What is the impact factors of angle of repose ? 静止角影响因素Impact factors: Including frictional forces generated by grain flowing against itself, the distribution of weight throughout the grain mass, and the moisture content of the grain. The angle of repose dete

21、rmines whether the grain will flow of its own accord or whether outside force is necessary to move it. 32. What is the hardness of grain ? 粮食硬度An important attribute of grains is their hardness, their resistance to being broken or reduced in particle size. （Large variation often even occurs within a

22、 single species (wheat, for example) of grain. The variation can be caused by both genetic differences and differences in the growing environment.）33.What is the practical significance of moisture in grain? 现实意义粮食水分Practical significance: determine the grains corresponding grade, price and quality;

23、and further affect the grains safe storage.34. Please introduce the important methods to measure the moisture content of grains and their products. 衡量粮食水分的方法Many methods have been developed to measure moisture content of grains and their products. The best known are :1) oven drying;2) vacuum oven dr

24、ying, with and without a desiccant; 3) distillation; 4) chemical reaction with the Karl Fischer reagent; 5) electronic devices or moisture meters; 6) nuclear magnetic resonance (NMR); 7) near- infrared ( NIR) spectrophotometry.35.What is the pesticide? 农药Pesticide: Anything that inhibits or kills a

25、pest such as weeds, fungi, insects, and rodents. 36. What is chemical grain protectant ? 杀虫剂Grain protectants are materials that will persist for extended periods at concentrations lethal to the target insects.37. What is fumigant ? 熏蒸剂A fumigant is a chemical that exists as a gas at ambient tempera

26、tures and pressures or produces a gas from a solid or a liquid. 38. What characteristics are an ideal fumigant should possess ? 熏蒸剂特征An ideal fumigant should 1) have low cost per effective fumigation;2) be highly and acutely toxic to all stages of the target pest, but not unduly hazardous to man and

27、 other higher animals; 3 ) be highly volatile, with a good ability to penetrate, but not be excessively absorbed by the commodity; 4) have adequate warning properties for easy detection;5) be noncorrosive, nonflammable, and nonexplosive under practical conditions; 6) possess a good storage life; 7)

28、be nonreactive with the commodity, so as not to produce adverse odors and flavors; 8) be readily removable by aeration, leaving no harmful residues;9) be noninjurious to seed germination; 10) be nondamaging to miling qualities or other processing properties of grain; 11) be readily available and sim

29、ple to apply. 39. What must you pay attention to when you use the fumigants to effectively control the stored-grain insects? 使用熏蒸剂控制昆虫Primary factors that decrease or increase the distribution of fumigants into grain and their biological activity are temperature, moisture, time, fumigant formulation

30、, dosage, application procedure, storage structure, aeration, dockage, insect population characteristics, and grain kernels. 40：What is the meaning of food processing ？ 食品加工的意义？答:Increase the value of agriculture products and by-products; 增加农业产品的价值和副产品; Prolong the storage period; 延长贮藏期; Improve the

31、 safety of food; 改善食品的安全问题; More nutritive、diversified and convenient. 更多的营养、多样化和方便41：The classification of food material . Point out some common food materials. 食品材料的分类。指出一些常见的食物材料。42：Classification of food nutrients. 。食物营养的分类。答：A) Macro Nutrients(宏量营养素） 1.Protein: Amino Acid (20 kinds) .蛋白质：氨基酸(20

32、种). 2.Lipids and Fats: Fat, Lecithoid, Cholesterin 脂类：脂肪、磷脂、胆固醇 3.Carbohydrates: Mono-, Oligo-, Poly-saccharides, and Fibre 碳水化合物：单糖, 低聚糖2 (220DP),多糖, 膳食纤维.4. Water: 水.B) Trace Nutrients(微量营养素)5. Minerals: (Inorganics,17 kinds), Ca, Zn, Fe 矿物质:（无机盐,17种）钙、锌、铁.6.Vitamins: Fat Soluble Vits(4 kinds), Water Soluble Vits(10kind维生素(14种)：脂溶性 (A,D,E,K), 水溶性(B族9种+