食品科学导论整理试题

introduction to food science test一、Please explain some special words?1、Homogenization（均化）：to obtain particles with certain dimensions2、Jam and jelly （果冻和果酱）：are gelled （凝胶, 冻胶）or thickened fruit products with a low pH. Preserved with sugars Include fruit butters, jellies,jams and similar products3、Gluten（麦麸）consists of two protein -Glutenin （麦醇溶蛋白）and -Gliadin （麦谷蛋白）They interact with each other by the kneading（和面；揉捏和）of a wet dough, to form a ‘protein complex’. Gluten isa highly elastic material4、Maillard （梅拉德反应）( nonenzymatic browning)：When reducing sugar presence from heat damage, certain amino acids decomposed from protain by heat, which on the high temperature condition, there forms brown pigments, flavors .5、Human essential amino acids：Human essential amino acids are which some of the amino acids human can not biosynthesize must be obtained from the diet by people.6、fermentation.:Adding yeast to sugars under anaerobic (without oxygen) conditions produces alcohol and carbon dioxide. This is called fermentation.7、Cholesterol:Cholesterol is a waxy, fat-like substance that occurs naturally in all parts of the body. Your body needs some cholesterol to work properly. But if you have too much in your blood, it can stick to the walls of your arteries. This is called plaque. Plaque can narrow your arteries or even block them.8、Water balance :That is total intake and losses from urine, faces, milk, saliva, sweating, and vaporization from respiratory tissues9、Water activity (a W): defined as RH(Relative Humidity ), which must prevail in the surrounding atmosphere to avoid water exchange between material and air; the ratio of the vapor pressures of pure water and a solution10. vitamin:A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. A compound is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet.11.Microorganisms:Microorganisms are tiny, mostly one-celled organisms capable of rapid reproduction under proper growth conditions.12.Food spoilage:Food spoilage is defined as any change in the organoleptic qualities (flavor, appearance odor or texture) of the food that makes the food unacceptable to the consumer.13.Shelf life: The time it takes a food product to deteriorate to an unacceptable degree under specific storage, processing, and packaging conditions.二、Fill in blanks1、Thanks to food science and technology and modern food manufacturing methods,nutritional deficiencies and inconsistent food availability can be addressed,harvests can be protected, and various commodities can be transformed into new products having specific nutrients for better health and wellness2、The main components in muscle are .Moisture Protein .Fat3、. the major Factors for fruit and vegetable deterioration are :①Enzymatic Changes; ②Chemical Changes; ③Physical Changes;④Biological Changes4、Enzymatic browning is usually undesirable when it occurs in foods such as apples, pears,lettuce（莴苣, 生菜）, potatoes, etc.5、Sensory quality of fruit and vegetable will be changed chemically for lipid oxidation; non-enzymatic browning; colour changes; flavour changes.6、The four major factors which affect fruit and vegetable nutrient degradation are light, oxygen concentration, temperature and water activity.7、Leavening Agents used to produce gas in batters that make baked products rise are steam,yeast and baking soda and powder8、in bread process, the dough should be avoid of over fermentation, if not, it will make cause gluen stretch, become weak and collapse, while coarse grain & sour odor due to excess acid production and less color in baked crust面包皮; 糕饼等的酥皮9、Milk is the first food of young mammals. It provides a high-quality protein, a source of energy, and vitamins and minerals.10、Carbohydrates are chains of repeating molecules of glucose and other sugars.11、Proteins are made up of chains of amino acids. There are different amino acids in a protein.12、Fats are made up of lipids. A lipid has a structure of three fatty acids molecules and a glycerol (甘油,丙三醇)molecule.13、A peptide bond is a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amine group of the other molecule, thereby releasing a molecule of water.14、Protein has a very big MW（molecular weight ）, thus it can form hydrophilic colloid while protein is dissolved in water;15、Carbohydrates include monosaccharides; disaccharides; oligosaccharides and polysaccardies16、Natural Starch conformation is the mixture of amylose and amylopectin17、Vitamins are classified by their biological and chemical activity, not their structure.18、Vitamin divided by the solubility. Water-soluble vitamins (dissolve easily in water) 9 water-soluble (B1, 2, 3, 5, 6, 7, 9, 12 and C)19、Fat-soluble vitamins(absorbed through the intestinal tract with the help of lipids) 4 fat-soluble (A, D, E, K)20、The main groups of additives are: flavourings; colourings; preservatives and antioxidants; emulsifiers and stabilisers.21、Taste quality different from receptors for sweet, bitter, salty, sour, the 4 primary tastes, Cannot be reproduced by mixing of chemicals or of any of the 4 primary tastes22、Apart from adding flavourings to food enhances the taste , some other additives are used in food such as Colourings; Colourings;; Colourings ; Stabilizers23、the nutrition value of fat is that it can provide high energy , fat- soluble vitamin and essential fatty acid.24、fat have important role for food which be as carriers of flavor, advance food smooth texture and mouth feel, can be heat transfer.25、The microbial world comprised of 2 cellular types: (except virus) Eukaryotic cells (真核细胞, the Eucarya); Prokaryotic cells (原核细胞):26、Those microorganisms important in the food industry include the bacteria, viruses, yeasts, molds, and protozoans.27、Microorganisms growth curve in liquid has four phase: lag phase;exponential phase:stationary phase, decline phase:28、Growth of microorganisms can be manipulated by controlling some factors:①Nutrients available; ②Oxygen; ③Water; ④Temperature; ⑤Acidity and pH; ⑥Light; ⑦Chemicals29、Nutrients such as carbohydrates, nitrogen source(proteins) , energy source (such as fats ), growth factor (vitamins etc.), minerals and water, required by, mainly are also needed by microorganisms to grow.30、Factors affecting microbial growth in food preserve are Temperature; Relative humidity; Atmosphere; Modified atmosphere packaging (MAP)31、Food-borne illness （食源性病）----The sickness resulting from eating food contaminated with either bacterial toxins or by certain bacteria in the food, often resulting in vomiting（呕吐）, diarrhea（腹泻）and prostration（衰竭、虚脱）32、Food-borne diseases （食源性病）are most often caused by several species of bacteria, although viruses, parasites（寄生生物）, amoebas（阿米巴）and other biological as well as chemical agents may be responsible.三.please make the right choices .1、There are three kinds of muscles, which is mainly consumed and processed?(1)Skeletal muscles（骨骼肌,横纹肌）, （）(2)Smooth muscles（平滑肌）,(3)Heart muscles（心肌）.2、The main component part is protein except water to take up 18%～20%，80% solid in meat , Muscle Proteins can be classifild to three kinds, that is(1)Myofibrillar proteins（肌原纤维蛋白质）(2)Sarcoplasmic proteins（肌浆蛋白）(3)Stroma proteins（肉基质蛋白质）3、which is not Berries?(1)Grape （2）strawberry （3）coconut( √)4、which is not Pip fruits(仁果类果实)(1) apple, (2) pear, (3)chestnut（板栗）( √)5.which is not Foliar vegetables（叶菜类）?(1)spinach（菠菜），（2）celery芹菜（3）potato6.which is Floscular vegetables (花菜类）?(1)broccoli n. 甘蓝；花椰菜( √)(2)tomato番茄(3)mushroom7.Physical methods of reducing fruit and vegetable deteriorate(1)Heating (2)Cooling(3)Lowering of water content (drying/dehydration).√8.Physical methods of reducing fruit and vegetable deteriorate(1)Controlled and modified atmosphere storage(2) Irradiation（辐射）(3)Waxing（蜡封）of the surfa（水面）9.Chemical Methods of reducing fruit and vegetable deteriorate(1)Salting (2)Sugar addition (3)Canning10.Chemical Methods of reducing fruit and vegetable deteriorate(1)Artificial acidification (2)Ethyl alcohol addition （乙醇添加）(3)Antiseptic substance action（防腐剂作用）11、which are kinds of common used Flour(1)All-purpose flour（普通面粉；家用面粉；中筋面粉）(2)Cake flour（低筋面粉；蛋糕粉；细面粉）(3)Instant/quick-mixing flour（快速混合面粉）12、which are kinds of common used Flour(1)Instant/quick-mixing flour（快速混合面粉）(2)Self-rising flour（自发面粉----已含酵母的）(3)Whole wheat flour（全麦面粉）13、Fluids which do not obey Newton viscosity law are non-newtonian fluids. For example: （1）tomato puree （2）sour milk, (3)grease.14.What molecules are foods made of?1.Carbohydrates 2、water 3、Vitamins.15、What molecules are foods made of?1.proteins 2、fats 3、minerals16、Agents causing denaturation1 .Temperature 2. pH 3.Ionic strength (salts)17. Agents causing denaturation1. Enzymes2. Heat3. Oxidation18.Which one is hydrophilic gelatum?1.Tofu （）2.Soy-bean milk3.albumen（白蛋白）19. Which one is not hydrophilic colloid?1.albumen（白蛋白）2.tendon ( )k,20.which is not essential amino acid for human?1.methionine,2.lysine3.glutamic acid ( )21.which is essential amino acid for human?1.lysine ( )2.glutamic acid3.proline22. which is disaccharides:1.Maltose麦芽糖2.Frucose ( )ctose乳糖23. Which is not monosaccharides :1.Glucose2.Sucrose蔗糖( )3. Galactose半乳糖24.Whichm mineral is not major salt component?1.potassium,钾2.sodium,钠3.Al ( )25.Whichm mineral is major salt components1.Fe,2.Cu,3.calcium,钙( )26.The reasons for vitamin deficiency:(1) Shortage of resource ( ) (2) Reduced absorption ( )(3) Increase requirements ( )27.Which are Water-soluble vitamins include1.Vitamin A2.vitamin B ( )3.vitamin C. ( )28.Which are fat-soluble vitamins include1.Vitamin D ( )2.vitamin E ( )3.vitamin B29. Vitamins have diverse biochemical functions:Hormones (③),Antioxidants (④),Mediators of cell signaling and regulators of cell and tissue growth and differentiation (①),Precursors for coenzymes (②)①Vitamin A;②Vitamin B;③vitamin D;④Vitamin E30.which Microorganisms are Eukaryotic cells真核细胞1.fungi2.yeast ( )3.bacteria31.which Microorganisms are Prokaryotic cells (原核细胞):1.Bacteria ( )2.actinomyces放线菌3.yeast酵母菌32.Fermentation selects for the growth of one or more bacteria which then inhibit the growth of harmful microbes. Fermentation food is1.yogurt, ( )2.cheese, ( )3.buttermilk ( )33.These fermentation foods include,1 soy sauce, ( )2 alcoholic beverages, and ( ) 3.vinegar. ( )四、Please answer Yes or No after each items .1.Without fat, all meats taste almost the same! (√)2. During Rigor Mortis process,the cells will continue to produce energy (ATP) by breaking down glycogen reserves, which produces lactic acid, dropping the pH to 5.2-5.6. (√)3. Waxing of the surface retards the rate of moisture loss, and maintains turgor （皮肤饱满）and plumpness（丰满度；肥胖度）and may modify the internal atmosphere(√)4.Modified atmosphere packaging of strawberries (carbon dioxide-enriched air delays fungal growth延迟真菌生长(√)5Flour composition critical （面粉成分标准）for the fermentation and physical structure of the dough and finished bread. (√)6Flour-Usually “all purpose flour” used for baking breads. Main function is to give structure to the bread. (√)7Almost all of the gluten forms during the kneading stage. It is important to not add too much extra flour while kneading. This will make the dough far too stiff （硬的）.8、The role of milk in nature is to nourish(滋养)and provide immunological protection for the mammalian young. (√)9.Changing the shapes of proteins also changes their properties. They become easier to digest and moreuseful to the cells of the human body. (√)10. To make proteins, a cell must have all needed amino acids available simultaneously (√)11.If the diet supplies too little of any essential amino acid , protein synthesis is limited. (√)12.Biological value can be improved by feeding two or more low quality protein feeds together if they are complimentary(√)13.Overfeeding on protein does not increase the amino acid level, starvation does not decrease it(√)14.Amino acids will be sacrificed to provide energy and glucose if needed when glucose and fatty acids are limited(√)k, fruit, vegetables, meat, soups and sauces can all be dehydrated to stop them from spoiling(√)16.Water Activity large effect on chemical reactions and microbial growth rate(√)17.Sodium ions are necessary for regulation of blood and body fluids, transmission of nerve impulses, heart activity, and certain metabolic functions. (√)18.Severe dehydration(脱水) will lead to very high blood sodium concentrations,but too rapid correction may result in brain damage from cellular swelling. (√)19.Microorganisms, like other living organisms, are dependent on their environment to provide for their basic needs. Adverse conditions can alter their growth rate or kill them. ( √)20.Microorganisms growth changing with temperature would gain high quality and quantity products during process ( √)21.A spoiled food is not necessarily unsafe to eat, but unpalatable(味道差的) to the consumer. Foods are attacked in a variety of ways that are harmful to the quality of the food ( √)五、Please give the answer for each Question.1.what does the course of Introduction to Food Science (UK) focus on ?Introduction to Food Science (UK) is the required course for food science and engineering major , mainly Introducting and reviewing to food ingredients, processing, package, market and storage and their complex relationship in bilingual language (English and Chinese ), while it is explored that how these factors affect the quality and safety of food.2.what is the request for students after course ?after the course, students should understand and master the basic components of food and the most commonly process , technology and equipment used in food processing , integrating the professional talent necessary to develop advanced products basing on the professional theory and professional English, which is the basis for students entering the higher grades to learn more advanced theory and more specialized knowledge.3.what the concepts of food science and technology ?Food Science is the discipline in which the engineering, biological, and physical sciences are used to study the nature of foods, the causes of deterioration, the principles underlying food processing, and the improvement of foods for the consuming public.Food Technology is the application of food science to the selection, preservation, processing, packaging, distribution, and use of safe, nutritious, and whole some food.In practice, the terms food science and food technology are often used interchangeably.4.How important is fat in food?fat has some nutrition value as essential fatty acids to provide high energy, which be adventage for fat-soluble vitamin. Fat is good for carriers of flavor, smooth texture and mouth feel, while it is heat transfer media.5、what are requirements on varieties used for processing?（1）To consider of the yield, supply period, storage time, edible part ratio, physical quality, chemical compositions and sensory quality when choosing fruits and vegetables（2）The texture, chemical composition, yield, processing characteristics and harvesting time are closely related to the variety of fruits and vegetables（3）The fruits used for processing should follow the requirements below: high acid，adequate ratio of sugar to acid, small core and stone, rich pulp（果肉）, tight and micromesh（细致的）texture, strong heat endurance, bigger percentage of edible part, and with good color, aroma and taste.（4）The vegetables used for processing should be rich in pulp（果肉）, have tender and micromesh texture, less crude fiber, much edible part and good color.6. The standards for a good variety of fruit and vegetable:①Stable and yield.②Long period’s supply.③Convenient to mechanized farming and harvesting④Strong resistance to plant diseases and insect pets，long storage time，good adaptability.⑤Sensory quality meets there quirements of processing.7.What are the Enzymic Changes for fruit and vegetable ?Oxidation of phenolic substances (苯酚) by phenolase (苯酚酶) (leading to enzymatic browning酶促褐变);• Sugar - starch conversion by amylases(淀粉酶);• Post-harvest demethylation（脱甲基化）of pectic substances （果胶物质）8.What are the principles thof Preservation that sugar used in jam and jelly can prevent the growth of microorganisms?(1)Add sugar to increase osmotic pressure（渗透压）to prevent microorganism development.(2)In food preservation with sugar, water activity can’t be reduced < 0.845 --- sufficient for bacteria andyeast inhibition, but does not prevent mold attack.9.what is gluten and How about is it in bread process?Gluten consists of two protein: -Glutenin （麦醇溶蛋白）and -Gliadin （麦谷蛋白）• They interact with each other by the kneading（和面；揉捏和）of a wet dough, to form a ‘protein complex• Gluten is a highly elastic material–Protein complex gives bread structure and elasticity and essential doe the leavening process–Poorly formed or absent in nonwheat flours–Most commercial breads contain some wheat10、How does baking powder make cakes rise?Baking powder contains:sodium hydrogencarbonate (碳酸氢钠). When this is heated during cooking it breaks down into sodium carbonate, carbon dioxide gas and water.---It is the carbon dioxide gas that makes the cakes rise.11、Yeast makes bread rise?!1.Yeast is a type of fungus. It is used to make bread rise. Bread is usually made from wheat flour. As yeast digests the carbohydrates in flour it produces carbon dioxide.2.Making bread from yeast is an aerobic reaction. This means it needs oxygen.3.Once the yeast has been added, the uncooked dough is left to rise.12、What is the chemistry of milk?The principal constituents of milk are water, fat, proteins, lactose (milk sugar) and minerals (salts). Milk also contains trace amounts of other substances such as pigments, enzymes, vitamins, phospholipids (substances with fatlike properties), and gases.Cows’milk consists of about 87% water and 13% dry substance. The dry substance is suspended or dissolved in the water.13.Why do eggs look different before or after cooked?Eggs are a protein food and so are made up of amino acids. When eggs are cooked they become firmer. This is because cooking eggs changes the shape of the amino acids chains. This is called denaturing.14.what is the protain isoelectric point ?At isoelectric point (specific for each protein),positive charges = negative charges →total charge = 0No charge –no repulsion –clotting of protein – e.g. production of dairy products (milk isoelectric point at pH 4.5)15.how about is the results after that enzymes act on protein ?1.Proteolytic enzymes (pepsin（胃蛋白酶）, rennin（凝乳酶）, trypsin（胰蛋白酶）) hydrolyze peptide bonds of protein →can lead to large changes in structure & function2.Desirable & undesirable changes during processing & storage of proteins3.Lead to changes in peptide side chains, make some amino acids unavailable, indigestible16、what is the most common food proteins in our daily food?Egg white, blood usually contain albumin白蛋白, but myofibrillar protein（肌纤维蛋白）is from Actin, myosin（肌球蛋白）in muscles.Gluten（谷蛋白、麸质或面精）in wheat can make dough good structure for bread making. most Connective tissue inLigaments（韧带）, fibrous contains much more collagen（胶原蛋白）, while milk protein mainly is casein(酪蛋白).17、What is the physiological functions of proteins & amino acids?Composition of body, improve growth• Composition of enzymes and hormone, regulate biological function• Form antibody, improve the immune-activity of body• Regulate osmotic pressure, otherwise protein-energy malnutrition.• Supplement of energy• Keep the flexible of skin• Transport fat, iron, oxygen and CO218、What is Physiologic roles of Lipids and Fats?(1).Source of energy (during sustained activity)1 g food lipid can produce 37.7kJ (9kcal) energy in body.(2). Structure of cell membrane.(3). maintain body temperature normally.(4). Protect viscera (脏器) from harmful.(5).Play some role in endocrine(内分泌作用).(6).Offer essential fatty acid. Such as linolie acid亚油酸, linolenic acid -亚麻酸。