Lesson 2 carbohydrate.ppt

1、Lesson 2 Carbohydrates,The food scientist has a many-sided interest in carbohydrates. He is concerned with their amounts in various foods, availability (nutritional and economic), methods of extraction and analysis, commercial forms and purity, nutritional value, physiological effects, and functiona

2、l properties in foods. Notes： (1) many-sided: adj.多边的,多方面的 broad in learning and many-sided in abilities 博学多才 His thoughts of Buddhism(佛学) was rich and many-sided.,(2) extraction： 提取(法),萃取(法),抽提法； extraction treatment of waste water; 废水萃取处理 solvent extraction; 溶剂萃取 supercritical fluid extraction：超临界

3、流体萃取 拔牙血统,家世摘要 (3) purity: 纯度 (4) physiological: 生理学的; 生理的 He bought a physiological book. The doctor had a test on the physiological reaction of human being. physiologic:生理学的生理的 physiology: 生理学生理机能 He bought a book about physiology.,Understanding their functional properties in processed foods requi

4、res not only knowledge of the physical and chemical properties of isolated carbohydrates, but also knowledge of the reactions and interactions (that occur in situs between carbohydrates and other food constituents) and the effects of these changes upon food quality and acceptance. This is a tall ord

5、er for knowledge. Notes ： 定语从句 processed:adj. 加工过的，经过加工的 processed foods ：加工过的食品,(3) 转折句： not onlybut also (4) situs：位置，地点 ,同site及position in situs: 就地，现场 (5) tall：adj. 高的, 身材高的; （用以表示或询问高度）有高的，身高; He is six feet tall. 难以置信的; 难以完成的 tall order :极难办的差使;很难做的工作苛求； Finishing this work in time was a tall

6、order but we did it.,Because processing affects both nutritional and esthetic values of food, knowledge of the changes that carbohydrates undergo during milling, cooking, dehydration, freezing, and storage is especially important. Notes ： (1) Esthetic: 有关美的, 美学的 ; esthetic values 美学价值 审美的 My estheti

7、c standards are quite different from his. 悦目的, 雅致的 That armchair is comfortable but not very esthetic.,(2) undergo:经历，经受（变化、不快的事等） He underwent a lot of hardships in his childhood. (3) milling： 磨,制粉,轧齿边 (硬币边缘的)沟槽 clean grain before milling it. mill: n. 磨坊; 磨粉机 作坊, 工厂 The farmer took his grain to the

8、 mill. Paper is made in a paper mill. vt. （用磨粉机）碾碎，磨成粉; （在硬币边缘）轧花边 mill around/about :无目的走来走去，绕圈子(由于迷惑) There was a crowd of people milling about in the streets.,(4) cooking：n. 烹饪术, 烹饪 Im inexpert at cooking. 如火如荼地进行；热火朝天 Business may have been a little slow at first, but now were cooking with gas!

9、在干什么；怎么 Whats cooking in here? You all look very guilty(鬼鬼祟祟的)! cook: vt. 篡改 He is quite capable of cooking the evidence. 密谋；秘密策划 n. 做饭的人, 厨师 My mother is a terrific cook!,(5) dehydration：n. 脱水 ,脱水作用 He died from severe dehydration. 干燥;极度口渴 dehydrate: vt. 使脱水, 使干燥 vi. (人体的)脱水, 失水 People can very qui

10、ckly dehydrate in the desert.,(6) freezing：n. 冷冻贮藏；冷藏 adj. 严寒的 It is freezing outside, and put on your winter coat. 冰冻的；冰点以下的 freeze vt. 冻结 冰冻期；严寒期,常用词组 freeze out ：排挤；逼走；将逐出 The others tried to freeze me out of the conversation. freeze ones blood ：使（某人）惊呆 A scream that froze my blood. freeze on to

11、：紧紧抓住；专心于 Well freeze on to those facts.,(7) storage ： 贮存, 贮藏 The fish should be kept in cold storage. 储藏处, 仓库 How much will you have to pay the warehouse for storage?,Students are advised to study the fundamental chemistry underlying useful carbohydrates properties. Of service will be an understand

12、ing (of the association of polar molecules through hydrogen bonding, ionic effects, substituent effects, chelation with inorganic ions, complexing with lipids and proteins, and decomposition reaction). Notes ： (1) 倒装句： (2) fundamental chemistry : 基础化学,(3) underlying : adj. 根本的, 基础的 含蓄的, 潜在的,隐含的 This

13、 word has its underlying meaning. 表面下的；下层的 underlie: vt. 位于或存在于(某物)之下 构成的基础(或起因); 引起; 作为的原因 I think a lack of confidence underlies his manner. (4) be of service :可以给某人帮助 of service:有用处的，有帮助的,(5) hydrogen bonding:氢键键合 (6) ionic effects:离子效应 (7) substituent effects: 取代基效应 (8) chelation: 螯合 (9) decompo

14、sition reaction:分解反应,This background will provide an understanding of properties that affect the texture and acceptance of processed foods (e.g., solubility, hygroscopicity, diffusion, osmosis, viscosity, plasticity, and flavor production), properties that enable the formation or high quality pastri

15、es, gels, coatings, confections, and reconstitutable dehydrated and frozen foods. Notes ： (1) solubility ：n. 溶解度 (2) hygroscopicity ：吸湿性 (3) diffusion: 扩散性,(4) osmosis：渗透性 (5) viscosity：粘度 (6) plasticity:可塑性 (7) pastry: 糕点,油酥糕点 ;油酥面团；油酥面皮 (8) gel:凝胶 (9) coating: 糖衣 ；涂层,（薄的）覆盖层外衣布料 (10) confection: 甜

16、食,糕点糖果 (candy) fruit confection (11) reconstitutable：adj. 可复水的 (12) frozen foods: 冷冻食品,Ability (to predict (what changes in functional properties are likely to ensue from incorporating various types of carbohydrates into processed foods) is a practical goal of the food scientist. Notes ： (1) 宾语从句;定语

17、 (2) predict:预言; 预测; 预示; 预告; 预报 She predicted that he would marry a doctor. (3) functional property: 功能特性 (4) ensue: vi. 接着发生, 因而产生, 接踵而来 Who knows what troubles may ensue from air pollution? (5) incorporate: vt. 包含, 加上, 吸收; 把合并, 使并入组成公司使混合 The shopping centre also incorporates a library and a bank.

18、,Such forecasting requires either a wealth of experience with trial-and-error methods or a deep knowledge of carbohydrate properties as related to structureperhaps both. Notes ： (1) forecasting:n.预测 forecast: vt. 预言, 预报，预测 Now scientists can forecast the weather accurately. n. 预测，预报 (2) a wealth of

19、:大量的, 丰富的 Theres a wealth of books in the library. (3) trial-and-error ：adj. 反复试验的，摸索的 trial and error：反复试验, 从失败中找到解决办法 He learned technical skills by trial and error. Growth is a process of trial and error: experimentation.,However, scientific knowledge of cause and effect is highly respected when

20、it shortens industrial development time. Notes ： (1) cause and effect ： 因果 The cause and effect relationship in nature is often subtle (奥妙的) and complicated (2) respect: vt. 尊重, 敬佩; 慎重对待；谨慎从事；尊重遵守；不损害；不违背尊敬；仰慕关心；考虑；关于；涉及 Please respect yourself. The terms of the agreement respect the boundary line b

21、etween the two countries.,常用词组 in respect of (or with respect to) ：关于，至于；就而言 The two groups were similar with respect to age, sex, and diagnoses. in respect that ：鉴于,在方面 In that respect his friend had greatly the advantage. pay ones last respects:向（死者）告别 Hundreds came to pay their last respects to t

22、he dead president with (或 with all due) respect ： 尽管（对您）尊敬之至 用于表示异议或批评的话之前 With all due respect, Father, I think youve got to be more broad-minded these days.,Source, Types, and Terminology,The laymans conception of carbohydrates generally involves only the sugars and starches of foodsthose that gen

23、erate calories and fat. The food chemist knows many other types that are ingested. Notes ： (1) terminology :n. 专门用语；术语；术语学 I dont understand scientific terminology. 术语的正确使用, 术语用法 (2) layman: n. 门外汉, 外行人 These technical terms are difficult for the layman to understand.,(3) sugar :n. 糖 vt. 在加糖;给裹上(糖衣或

24、类糖物) Did you sugar my tea? The roads had been cleaned of snow, but the roof tops, grass and trees were still sugared white. (4) calory:卡路里 (5) ingest: vt. 1.吃;吞下 获取(某事物) to ingest food,Because most people enjoy the sweetness of sugars and the mouth feel of cooked starches, they become familiar by as

25、sociation with table sugar (sucrose), invert sugar（hydrolyzed sucrose）, corn syrup sugars (D-glucose and maltose), milk sugar (lactose), and the more starchy foods. Note : (1) sweetness:甜，甜味 This is a full-bodied(味道醇厚的) wine with just a hint of sweetness. 令人愉快;讨人喜欢 (人)和蔼可亲；亲切友善 Shes all sweetness an

26、d light as long as youre doing what she wants. (情况)良好；顺利 Their quarrel seems to be over. Everythings all sweetness and light at the moment.,(2) mouth feel : n. 口感 (3) table sugar:蔗糖 sucrose sju:krus :蔗糖 (4) invert sugar:转化糖 hydrolyzed sucrose: 蔗糖水解产物 (5) corn syrup sugars：淀粉糖浆 syrup：n. 糖浆，糖汁 (6) D-g

27、lucose : D-葡萄糖 (7) Maltose m:ltus :麦芽糖 (8) milk sugar：乳糖 lactoselkts ：乳糖 (9) starchy: adj. (食物)含大量淀粉的刻板的;拘谨的 Dont be so starchy,These carbohydrates are nutritionally available; i.e., they are digested (hydrolyzed to component monosaccharides) and utilized by the human body. Carbohydrates of dietary

28、fiber (cellulose, hemicelluse,pentosans, and pectic substances), in contrast, tend to be overlooked because they are largely unavailable. Digestive enzymes do not hydrolyze them significantly; nevertheless, they may be quite important for human health.,Notes ： (1) i.e.：即,换言之 (2) monosaccharide:单糖mon

29、osaccharose; monose; simple sugar oligosaccharide; oligose：寡糖 polysaccharide; polysaccharose：多糖 (3) dietary fiber：膳食纤维 (4) celluloseseljls :纤维素 (5) hemicelluse：半纤维素 (6) pentosan：戊聚糖,多缩戊糖 (7) pectic substances：果胶物质,(8) overlook：忽视,未注意到 Dont overlook the slower students. 原谅 We decided to overlook his

30、mistake. 监督, 管理 The foreman(工头) overlooked a large number of workers. 俯视,眺望 We overlooked the sea. （提拔等时）对（某人）不予考虑 （对不良现象等）不予理会，视而不见 (9) digestive enzymes: defective enzymes消化酶 (10) significantly :意味深长地；值得注目地；显著地，有效地 Eating a good diet significantly lessens the risk of heart disease.,The carbohydrat

31、es of natural and processed foods are divided into available and unavailable types. The available carbohydrates vary in degrees of absorption and utilization depending upon quantities ingested, accompanying food types, and human differences in complements of defective enzymes and intestinal transpor

32、t mechanisms. Malabsorption difficulties and adverse physiological effects are known for all the available carbohydrates but gelatinized starches give little or no trouble.,Notes ： (1) vary in :在方面不同 (2) intestinal: adj. 肠的，肠道的 intestine ：n. 肠 (3) malabsorption: n. (营养)吸收障碍,吸收不良 (4) adverse physiolo

33、gical effects ：负面的生理影响 (5) gelatinized starches ：糊化胶凝淀粉,It is important to realize that in ruminants the unavailable and most abundant polysaccharide cellulose is partially hydrolyzed to the same highly available sugar that starch provides upon digestion; i.e. D-glucose. Grazing animals do it throug

34、h the cellulases generated by the microorganisms of their rumen. Cellulose is, therefore, a contributing source of valuble animal protein.,Notes ： (1) ruminant: n.反刍动物 The cow is a ruminant. adj. 反刍的;沉思默想的 (2) grazing animals:食草动物;放牧牲畜 grazing: n. 放牧;牧场;草场 continuous grazing:连续放牧 normal grazing:正常放牧

35、 graze: vi. 擦破, 擦伤（皮肤） He has grazed his knee. 擦过, 掠过 The plane grazed the hilltops. （经过时）轻擦，轻触，蹭 n. 擦伤,grazer:吃草的动物 grazier: n.放牧人 graziery ：畜牧业 cellulases：n.纤维素酶 (4) microorganisms n.微生物 The diseased tissue can be easily invaded by these microorganisms. (5) rumen :瘤胃(反刍动物的第一胃),The efficiency and e

36、conomics (of the ruminants conversion of cellulose to nutrients) probably can improve upon by food chemists. Development of cellulases (that are stable outside the cells of microorganisms ) enables the culturing of fungi and yeasts on cellulose hydrolyzates. Notes ： (1) culture:n. 文化 休养, 教养, 精神文明 Sh

37、e is a woman of culture and taste. 养殖, 培养, 栽培 【生物学】(微生物等的)培养；(培养出的)微生物；培养细胞；培养菌 vt. 培植, 培养 【生物学】培养(微生物、细胞组织等)；用(某营养物质)作培养基,(2) fungi: n. (fungus的复数) 真菌霉；霉菌 Mushrooms are a type of fungus. fungous: adj. 真菌状的,有真菌特征的 (3) yeast: n. 酵母；酵母菌 yeast cake:发面饼, 鲜酵母块 yeast powder:发酵粉, 酵母的代用品,Fungi (e.g., mushro

38、oms) can produce protein with the biological value of animal protein. The conversion of cellulose wastes to animal feed and human food is an intriguing prospect for limiting environmental pollution and for feeding the worlds expending population. Notes ： (1) intriguing ：adj. 非常有趣的；引人入胜的；神秘的 It all s

39、ounds very intriguing. (2) prospect: n. 景象, 景色 From the top of the hill theres a beautiful prospect over the valley. 前景; 前途 John is in high spirits at the prospects. 可能成为主顾的人; 有希望的候选人 Shes a good prospect for the national team. 可能性；希望 vi. 勘探; 勘察 .(矿等)有希望，有前途 vt. 勘探；勘察；找矿 对进行仔细调查,Carbohydrates were f

40、irst named according to their natural sources; e.g., beet sugar, cane sugar, grape sugar, malt sugar, milk sugar, cornstarch, liver glycogen, and sweet corn glycogen. Notes: (1) beet sugar:甜菜糖 (2) cane sugar：甘蔗糖 (3) grape sugar：葡萄糖 (4) malt sugar：麦芽糖 (5) milk sugar：乳糖 (6) Cornstarch：玉米淀粉 (7) liver g

41、lycogen：肝糖原 (8) sweet corn glycogen：甜玉米糖原,Trivial names were then formed, in English terminology, often from a prefix related to the source followed by the suffix “-ose” to denote carbohydrate. Names arising in this way, for example, are fructose, maltose, lactose, xylose, and cellulose. These short

42、, well-established names are still commonly used. Notes ： (1) trivial name: n. 俗名 (2) terminology : n. 术语 (3) prefix : n.前缀 vt. 在加上前缀 (4) suffix: n. 后缀, 词尾 ; vt. 加后缀, 加词尾 (5)denote:vt. 为的符号; 为的名称,标志；预示；象征指示; 指出,表示；意指,(6) fructose : n.果糖 (7) maltose : n.麦芽糖 (malt sugar) (8) lactose : n. 乳糖 (milk suga

43、r) (9) xylose : n.木糖,戊醛糖 (10) cellulose: n. 纤维素 (11) well-established: adj.已为大家接受的;信誉卓著的 生了根的;根深蒂固的.,They furnish no information on the chemical structures, however, so a definitive carbohydrate nomenclature has been developed. From the definitive names, structural formulas can be written. Some of t

44、he terms involved in the definitive nomenclature are explained in the following paragraphs. Notes ： (1) definitive：adj. 最后的；决定性的；不可更改的 We got a definitive victory. 最佳的；最完整可靠的 (2) nomenclature :n. 命名法 (3) definitive nomenclature : 定形命名法,The simple sugars (monosaccharides) are basically aliphatic poly

45、hydroxy aldehydes and ketones: HOCH2-(CHOH)n-CHO and HOCH2-(CHOH)(n-1)-(C=O)-CH2OH, called “aldoses” and “ketoses,” respectively. However, it must be understood that cyclic hemiacetals of those open-chain forms prevail in solids and at equilibrium in solutions. Notes: (1) aliphatic: liftik adj.脂肪族的,

46、无环的 aliphatics: n.脂(肪)族化合物 (2) polyhydroxy: plihaidrksi adj.多羟(基)的; n.多羟(基) polyhydroxylated : adj. 多羟基化的 polyhydroxylation : n.多羟基化反应,(3) aldehydes: ldihaid n. 醛 (4) ketones : ki:tun n. 酮 (5) aliphatic polyhydroxy aldehydes :脂肪族多羟基醛 (6) aliphatic polyhydroxy ketones :脂肪族多羟基酮 (5) aldoses : ldus n. 醛

47、糖 (6) ketoses: ki:tus n. 酮糖 (7) hemiacetal: hemisitl n.半缩醛 cyclic hemiacetals : 环状半缩醛 (8) prevail: vi.胜(过),优胜,成功,奏效 流行,盛行,普遍 prevail on 说服,劝说,诱导,In the definitive nomenclature, the suffix “ose” is appended to prefixes denoting the number of carbon atoms in the monosaccaride; e.g. trioses (n=1), tetr

48、oses (n=2), pentoses (n=3), hexoses (n=4) to distinguish aldoses from ketoses, ketoses are designated as“-uloses.” Thus, the simplest ketose, HOCH2-(C=O)-CH2OH, is a triulose; the most common ketose, D-fructose (levulose), is a hexulose. Notes: (1) nomenclature : nmnkleit : 系统命名法；命名(过程) (某一学科的)术语,专门

49、名称 (2) suffix : sfks n.后缀, 词尾 vt.加后缀, 加词尾prefixes : 前缀 字首,(3) append vt.附加贴上,挂上 (4) denote : dinut vt. 1.为的符号; 为的名称,标志；预示；象征 In algebra, the sign X usually denotes an unknown quantity. 指示; 指出,表示；意指 We often denote danger by red letters. (5) trioses ：traius丙糖 tetroses ：tetrus丁糖 pentoses： pentus戊糖 hex

50、oses ：heksus已糖 (6) triulose: 丙酮糖 (7)levulose levjulus: n. 果糖 D-fructose: frktus: D-果糖 hexulose ：heksjlus已酮糖,To designate the configurations of hydroxyl groups on the asymmetric carbon atoms of monosaccharides, the prefixes D and L are used together with prefixes derived from the trivial sugar names

51、(e.g., D-glycero-, L-arabino-, D-xylo-) followed by pentose, hexose, hexulose, etc. Notes: (1) designate ：dezigneit 指派, 委任(某人任某职) The chairman has designated her as his successor. 标明, 指明, 命名 Will you designate the flowers you wish? 命名；指定 指出，指示 adj.（已受委派）尚未上任；（已当选）尚未就职,(3) configurations : knfigjurei

52、n n.构造, 形状, 外貌, 轮廓 Geographers study the configuration of the mountains. （计算机的）配置 (各部分之间的)编排，配置，布局 【化学】结构，构型，组态 【心理学】完形 【天文学】位形；组态 (5) asymmetric ：sim trik adj.不对称的,不匀称的 asymmetrical ：adj.不均匀的,不对称的 asymmetry eisimitri: n.不对称 adj.不对称的，不对等的,(6) trivial : trivil adj. 琐碎的, 没有价值的, 微不足道的; trivial matters

53、通俗的, 无趣的, 平常的 trivial name 俗名 (generic name ) 轻浮的, 无能的, 缺德的 (7) D-glycero-： D-甘油 L-arabino-: L-阿拉伯- D-xylo-： D-木-,As open-chain hydroxy aldehydes and hydroxyl ketones, the monosaccharides are very reactive. They readily enolize in alkaline solutions to reduce ions such as Cu2+ and Fe(CN)63-. Therefo

54、re, they are called “reducing sugars”. Notes: (1) enolize ：vt. 使烯醇化 enolization: enlaizein n.烯醇化(作用),(2) reduce: vt.缩减, 减少; 降低 He wont reduce the rent of our house. 降低某人的级别或地位; 降职；使陷入某种状态状况中; Hunger reduced him to steal. 将概括简化,驱散 The rising sun quickly reduced the fog. 将还原 A doctor can reduce a frac

55、ture（骨折） or dislocation（脱臼）. vi.减轻体重; 节食 I must reduce to get into that fine dress. (3) reducing sugars: 还原糖,Plants protect the reactive monosaccharides for transport and storage by condensing them with loss of water, into less reactive sugars, e.g., D-glucose and D-fructose, are condensing in such

56、a way that their reactive functions are lost to form the disaccharide no reducing sugar, sucrose. The less reactive sucrose is then transported to all parts of the plant for enzymic syntheses of oligo-and polysaccharides. Notes: (1) condense:kndns vt. (使)凝结 vt.简说, 摘要, 简述. I have condensed my report.

57、 (2) disaccharide : 二糖 oligosaccharides: 寡糖，低聚糖 polysaccharides：多糖，多聚糖 (3) no reducing sugar：非还原性糖，无还原性糖,From thousands or more D-glucose moieties of sucrose, the glucans, starch and cellulose, are built. From the D-fructose moiety of sucrose, fructans such as inulin are assembled. Other polysacchar

58、ides are formed from other sugar, which rose by enzymic transformations of phosphorylated hexoses and sugar nucleotides. Notes: (1) glucan ： lu:kn n.葡聚糖 (2) fructan: frktn n.果聚糖 (3) inulininjulin n.菊粉 inulaseinjuleis菊粉酶 (3) phosphorylated hexoses : 磷酸化己糖 phosphorylate：fsfrileit磷酸化 phosphorylase：磷酸化酶

59、 (4) sugar nucleotides ：核苷酸糖 nucleotidenju: kli:,taid核苷酸 nucleotidase 核苷酶 nucleoside核苷nucleoprotein核蛋白,The prefix “glyc,” is used in a generic sense to designate sugars and their derivatives; e.g., glycoses, glycosides, glycosans, glyconic, glyceric, and glycuronic acids. The generic name for polysaccharides is “glycans”. Notes: (1) glyc : n.甘油,丙三醇 glyc-: 糖- (2) generic sense ：一般意义 (3) glycoses ：单糖 (3) glycosides ：糖苷, 配糖物 (4) glycosans：聚糖 (5) glyconic acid :葡萄糖酸 (6) glyceric acid: 甘油酸 (7) glycuronic acid ：葡萄糖醛酸 (8) glycan:多糖,聚糖,多聚