chapter 3 carbohydrate13

1、08-May-211Chapter Three Carbohydrate08-May-212FInstructionInstructionFMonosaccharideMonosaccharide: : structure, physical property, structure, physical property, chemical propertychemical propertyFOligosaccharideOligosaccharide: maltose, lactose, sucrose: maltose, lactose, sucroseFPolysaccharide:Pol

2、ysaccharide: starch, cellulosestarch, cellulose, , alginate jellyalginate jelly, , plant polysaccharide, microorganism plant polysaccharide, microorganism polysaccharide. polysaccharide. Contents單糖單糖低聚糖低聚糖多糖多糖海藻膠海藻膠淀粉，纖維素淀粉，纖維素08-May-213FKey points:Key points: mechanism and meaning mechanism and mea

3、ning of Maillard reaction; maltose; of Maillard reaction; maltose; lactose lactose intolerance resultsintolerance results; properties and ; properties and application of polysaccharide.application of polysaccharide.FDifficulty points:Difficulty points: mechanism and mechanism and meaning of Maillard

4、 reaction; structure meaning of Maillard reaction; structure and properties of starch and cellose.and properties of starch and cellose.乳糖不耐癥乳糖不耐癥08-May-2141 Introduction酮酮縮（合）聚物縮（合）聚物衍生物衍生物多羥基多羥基醛醛08-May-215FMonosaccharide:Monosaccharide: not be broken down to lower not be broken down to lower molec

5、ular weight carbohydrates by hydrolysis.molecular weight carbohydrates by hydrolysis.FOligosaccharide:Oligosaccharide: contain 2 to 10 sugar units contain 2 to 10 sugar units joined by joined by glycosidic bondsglycosidic bonds. .FPolysaccharide:Polysaccharide: are polymers of are polymers of monosa

6、ccharides.monosaccharides.1.2 classification糖苷鍵糖苷鍵08-May-216Flinear chainlinear chain and and branched chainbranched chain polysaccharide.polysaccharide.Fstructural, storage, and antigen structural, storage, and antigen polysaccharide.polysaccharide.Fplant, animal and microbial plant, animal and mic

7、robial polysaccharide.polysaccharide.1.2 classification直鏈直鏈支鏈支鏈08-May-217FruitD-glucoseD-fructosesucroseApple1.176.043.78Grape6.867.842.26Peach0.911.186.92Pear0.956.771.61Cherry6.497.380.22Strawberry2.092.401.03Free carbohydrate in fruits08-May-218VegetableD-glucoseD-fructosesucroseBeet0.180.166.11C

8、arrot0.850.854.24Cucumber0.870.860.06Lettuce0.070.160.07Onion2.071.090.89Spinach0.090.040.06Sweet corn0.340.313.03Tomato1.121.340.01Free carbohydrate in vegetables08-May-2192.1 structure2.1 structureFchiralchiral carbon atoms, in two different carbon atoms, in two different spatial configurationsspa

9、tial configurations. .FAcyclicAcyclic structure structure aldosealdose: C2 and C4 : C2 and C4 epimerismepimerism; ; ketosesketoses: C5 epimerism. : C5 epimerism. P159, 1114P159, 1114行行立體構(gòu)型立體構(gòu)型鏈?zhǔn)芥準(zhǔn)讲钕虍悩?gòu)差向異構(gòu)醛糖醛糖酮糖酮糖手性手性08-May-2110FD-sugar: the D-sugar: the hydroxyl grouphydroxyl group on the highest on

10、 the highest numbered chiral carbon atom positioned on numbered chiral carbon atom positioned on right-hand side; right-hand side; FL-sugar: left-hand side. L-sugar: left-hand side. P160,811P160,811行行aldosealdoseketosesketoses2 24 4羥基羥基08-May-2111FRing forms:Ring forms:F-C=O+-OH -C=O+-OH hemiacetalh

11、emiacetal or or hemigetalhemigetal, , pyranose pyranose or or furanose furanose ring. ring. P162, 1214P162, 1214行行2.1 structure of monosaccharide吡喃糖吡喃糖呋喃糖呋喃糖半縮酮半縮酮半縮醛半縮醛08-May-2112FC-1: the hydroxyl locate below the ring is C-1: the hydroxyl locate below the ring is form, and up the ring is form. fo

12、rm, and up the ring is form. P163, 510P163, 510行行08-May-2113FGlucopyranoseGlucopyranose: chair and boat form; : chair and boat form; chair form is more stability. chair form is more stability. P163, 1417P163, 1417行行chairchair boatboat2.1 structure of monosaccharide吡喃型葡萄糖吡喃型葡萄糖08-May-21142.1 structur

13、e of monosaccharide08-May-21152.2 physical property2.2 physical propertyFMutamerismMutamerism; ;FSolubility: increasing following Solubility: increasing following temperature; at the same temperature, temperature; at the same temperature, fructose is most easy to soluble.fructose is most easy to sol

14、uble.FHygroscopic and Hygroscopic and moisture retention: moisture retention: soften bread, cake, and soften bread, cake, and panochapanocha. .2 monosaccharide吸濕性吸濕性軟糖軟糖變旋變旋08-May-2116FCrystallinityCrystallinity: : sucroseglucosefructose and invert sucroseglucosefructose and invert sugarstarch syrup

15、sugarstarch syrupFViscosityViscosity: glucose and : glucose and fructosesucrose starch syrupfructosesucrose starch syrupFantioxidationantioxidationFcryoscopiccryoscopic2.2 physical property粘度粘度抗氧化性抗氧化性冰點(diǎn)冰點(diǎn)結(jié)晶性結(jié)晶性08-May-21171 reaction with 1 reaction with alkalinealkalineFIsomerousIsomerous and and di

16、saggrega-tiredisaggrega-tire in in alkalescence solution. alkalescence solution. Ffactorsfactors：category and structure of category and structure of monosaccharidemonosaccharide、variety and variety and concentration of alkalineconcentration of alkaline、reaction reaction temperature and time.temperat

17、ure and time.2.3 chemical property堿堿異構(gòu)化異構(gòu)化分解反應(yīng)分解反應(yīng)08-May-211808-May-21192 reaction with acid2 reaction with acidFAcid + monosaccharide oligosaccharideAcid + monosaccharide oligosaccharide2.3 chemical propertyxylosexyloseacidacidketoseketosefurfuralfurfural+ +5-hydroxide methyl 5-hydroxide methyl fur

18、furalfurfural戊醛糖戊醛糖酮糖酮糖糠醛糠醛5-5-羥甲基糠醛羥甲基糠醛08-May-21203 3 redoxredoxFOxidation of Oxidation of -glucose to -glucose to D-gluconic acidD-gluconic acid uses uses the the enzyme glucose oxidaseenzyme glucose oxidase. .FMeasure the amount of D-glucose in foods and Measure the amount of D-glucose in foods

19、and other biological material.other biological material.FUsed for the manufacture of commercial D-Used for the manufacture of commercial D-gluconic acid and its gluconic acid and its lactonelactone. .2.3 chemical property氧化還原作用氧化還原作用葡萄糖氧化酶葡萄糖氧化酶D-D-葡萄糖酸葡萄糖酸內(nèi)酯內(nèi)酯08-May-21212.3 chemical property08-May-

20、2122FAll monosaccharides are reducing sugar.All monosaccharides are reducing sugar.Fdissociate carbonyldissociate carbonyl is reduced to sugar alcohol. is reduced to sugar alcohol. D-glucose D-glucose D-glucitol (sorbitol)D-glucitol (sorbitol) D-fructose D-fructose sorbitol + mannitolsorbitol + mann

21、itol D-xylose D-xylose xylitolxylitolFXylitol is used in place of sucrose, there is a Xylitol is used in place of sucrose, there is a reduction in reduction in dental cariesdental caries. .2.3 chemical property游離游離羰基羰基D-D-葡萄糖醇葡萄糖醇（山梨醇）（山梨醇）木糖醇木糖醇山梨醇山梨醇+ +甘露甘露醇醇齲齒齲齒08-May-21234 4 glycosidesglycosides

22、Fhemiacetal hemiacetal form of sugars react with -form of sugars react with -OHOH、-NH-NH2 2 and -SH to produce a full and -SH to produce a full acetalacetal. .FFuran nucleus and pyranoid ringFuran nucleus and pyranoid ring. .Faglyconeaglycone: : alcoholic alcoholic group. group. P165, 11,1520P165, 1

23、1,1520行行2.3 chemical property糖的成苷作用糖的成苷作用半縮醛半縮醛縮醛化合物縮醛化合物呋喃環(huán)和吡喃環(huán)呋喃環(huán)和吡喃環(huán)糖苷配基糖苷配基醇基醇基08-May-2124FO-glycoside: OHO-glycoside: OHaglyconeFN-glycosideN-glycoside: NH: NH2FS-glycosideS-glycoside: SH: SHN-N-糖苷糖苷S-S-糖苷糖苷08-May-21255 hydroxyl group 5 hydroxyl group esters and ethersesters and ethersFEsters:E

24、sters: Fcarboxylate: phosphate, acetate, carboxylate: phosphate, acetate, sucrose fatty acid ester, sulfatesucrose fatty acid ester, sulfate . . FSucrose ester is a good emulsifier.Sucrose ester is a good emulsifier. P169,12,813P169,12,813行行RCOCRROH2.3 chemical property酯化和醚化作用酯化和醚化作用羧酸酯羧酸酯磷酸酯、醋酸酯、蔗糖

25、脂肪酸酯、硫酸酯磷酸酯、醋酸酯、蔗糖脂肪酸酯、硫酸酯 08-May-2126Fethers ethers FPolysaccharides are etherified to modify Polysaccharides are etherified to modify their properties and more useful.their properties and more useful.FHydroxypropyl ethersHydroxypropyl ethers of cellulose and of cellulose and hydroxypropyl ethers o

26、f starchhydroxypropyl ethers of starch. .F3,6-anhydro ring3,6-anhydro ring found in found in redred seaweed seaweed polysaccharides. polysaccharides. P169,1819,P170, 5P169,1819,P170, 5行行171,2171,2行行2.3 chemical property羥丙基醚羥丙基醚淀粉羥丙基醚淀粉羥丙基醚3,6-3,6-脫水環(huán)脫水環(huán) 紅藻多糖紅藻多糖 08-May-21272.3 chemical property08-Ma

27、y-21286 6 nonenzymic browningnonenzymic browningFMaillard reactionMaillard reaction: reaction between : reaction between reducing sugars, mainly D-glucose, and a reducing sugars, mainly D-glucose, and a free amino acid or a free amino group of an free amino acid or a free amino group of an amino aci

28、d that is part of a protein chain.amino acid that is part of a protein chain. P171,1823P171,18232.3 chemical property非酶褐變非酶褐變美拉德反應(yīng)美拉德反應(yīng)08-May-2129FThree primary elements: Three primary elements: nitrogen-nitrogen-containing compoundscontaining compounds, reducing sugars, , reducing sugars, and water

29、. and water. FCharacters: producing flavor and color. Characters: producing flavor and color. FDesirable: milk chocolate flavor, candy Desirable: milk chocolate flavor, candy flavor; flavor; FUndesirable: nutrition loss,Undesirable: nutrition loss, noxious noxious, and , and mutagenesismutagenesis m

30、aterial. material.2.3 chemical property含有氨基的化合物含有氨基的化合物致突變致突變有毒的有毒的08-May-2130FMaillard reaction processMaillard reaction processFSugar reacts with the amine to produce a Sugar reacts with the amine to produce a glycosylamineglycosylamine, undergoing the , undergoing the rearrangement to give a rear

31、rangement to give a derivativederivative of of 1- 1-amino-1-deoxy-D-fructose.amino-1-deoxy-D-fructose.2.3 chemical property葡基胺葡基胺 1-1-氨基氨基-1-1-脫氧脫氧-D-D果糖果糖 衍生物衍生物 08-May-2131FAt pH=5 or lower, reaction continues to At pH=5 or lower, reaction continues to give give 5-hydroxymethyl-2-furaldehyde.5-hyd

32、roxymethyl-2-furaldehyde. FAt higher than pH 5, HMF polymerize At higher than pH 5, HMF polymerize quickly to a dark-colored, insoluble quickly to a dark-colored, insoluble material containing nitrogen.material containing nitrogen. P171,2634P171,26342.3 chemical property5-5-羥甲基羥甲基-2-2-呋喃甲醛（呋喃甲醛（HMFH

33、MF） 08-May-213208-May-213308-May-2134FCondign conditionCondign condition of Maillard reaction of Maillard reactionD-xyloseD-xyloseL-arabic gumL-arabic gumhexosehexosedisaccharide disaccharide D-fructoseD-fructoseD-glucose D-glucose Middling water contentMiddling water contentpH 7.89.2pH 7.89.2Metal

34、ionMetal ion：Cu and Fe are Cu and Fe are accelerant, accelerant, FeFe+3+3FeFe+2+22.3 chemical property最適條件最適條件 D-D-木糖木糖L-L-阿拉伯糖己糖二糖阿拉伯糖己糖二糖 08-May-2135FRestrain Restrain method of Maillard reactionmethod of Maillard reactionDilution or reduceDilution or reduce water content water content Lower pH Lo

35、wer pH Low temperatureLow temperatureAccede to glucose transform enzymeAccede to glucose transform enzymeAccede to Accede to reducing agent (sulfite)reducing agent (sulfite) before before pigmentpigment forming. forming. P171,P171,最后一段最后一段2.3 chemical property抑制抑制稀釋或降低稀釋或降低加入葡萄糖轉(zhuǎn)化酶加入葡萄糖轉(zhuǎn)化酶還原劑還原劑色素色素

36、08-May-21367 7 caramelizationcaramelizationFHeating of carbohydrates and reducing Heating of carbohydrates and reducing sugar without nitrogen-containing sugar without nitrogen-containing compounds effects a complex group of compounds effects a complex group of reactions. reactions. P172,911P172,911

37、行行2.3 chemical property焦糖化反應(yīng)或卡拉蜜兒作用焦糖化反應(yīng)或卡拉蜜兒作用08-May-2137FAcidic caramel colorAcidic caramel color：pH 2-4.5, used in cola soft drinks, negative charges.FBaked caramel color:Baked caramel color: pH 4.2-4.8, used in baked goods, syrups, positive charges.FBeer caramel color:Beer caramel color: pH 3-4,

38、 used in beer and other alcoholic beverages, negative charges. P173,18P173,18行行2.3 chemical property耐酸焦糖色素耐酸焦糖色素 焙烤食品用色素焙烤食品用色素啤酒等含醇飲料用焦糖色素啤酒等含醇飲料用焦糖色素可樂等酸性飲料可樂等酸性飲料糖漿糖漿含醇飲料含醇飲料08-May-2138F葡萄糖葡萄糖(C(C6 6H H1212OO6 6) )：無色晶體或白色粉末，無色晶體或白色粉末，易溶于水易溶于水 。F葡萄糖以水果和蜂蜜中的含量為多。葡萄糖以水果和蜂蜜中的含量為多。F工業(yè)生產(chǎn)中從玉米和馬鈴薯中的淀粉制取

39、。工業(yè)生產(chǎn)中從玉米和馬鈴薯中的淀粉制取。F食品中用于生產(chǎn)面包、糖果、糕點(diǎn)、飲料等。食品中用于生產(chǎn)面包、糖果、糕點(diǎn)、飲料等。 2.4 2.4 幾種主要的單糖幾種主要的單糖08-May-2139F果糖果糖(C(C6 6H H1212OO6 6) )：白色晶體或粉末，是最甜白色晶體或粉末，是最甜的糖，易溶于水、乙醇和乙醚。的糖，易溶于水、乙醇和乙醚。F存于水果、蜂蜜中，菊粉水解制取。存于水果、蜂蜜中，菊粉水解制取。08-May-2140F工業(yè)上：用淀粉水解制備葡萄糖，經(jīng)固工業(yè)上：用淀粉水解制備葡萄糖，經(jīng)固定化葡萄糖異構(gòu)酶轉(zhuǎn)化為轉(zhuǎn)化糖，含有定化葡萄糖異構(gòu)酶轉(zhuǎn)化為轉(zhuǎn)化糖，含有4242果糖、果糖、5858

40、葡萄糖，商業(yè)上稱果葡葡萄糖，商業(yè)上稱果葡糖漿或高果糖漿，甜度與蔗糖相當(dāng)，具糖漿或高果糖漿，甜度與蔗糖相當(dāng)，具有天然蜂蜜香味，生產(chǎn)成本低，廣泛用有天然蜂蜜香味，生產(chǎn)成本低，廣泛用于飲料和糖果糕點(diǎn)等食品工業(yè)。于飲料和糖果糕點(diǎn)等食品工業(yè)。08-May-21411 Maltose 1 Maltose P174,4.2.1P174,4.2.1FTwo molecule of pyranose glucose combined Two molecule of pyranose glucose combined by -1,4 glycosideby -1,4 glycoside. .maltose (-D

41、-pyranose glucose-(1 4)-D-pyranose glycoside)maltose (-D-pyranose glucose-(1 4)-D-pyranose glycoside)1 43 Oligosaccharides3 Oligosaccharides3.1 oligosaccharides in foods3.1 oligosaccharides in foods兩分子吡喃葡萄糖通過兩分子吡喃葡萄糖通過-1-1，4 4糖苷鍵結(jié)糖苷鍵結(jié)合合 08-May-2142FColorless or white crystalColorless or white crysta

42、l; ;FA reducing sugar;A reducing sugar;FDissolve in water and Dissolve in water and ethanolethanol; ;FFerment by yeastFerment by yeast. .3.1 oligosaccharides in foods3.1 oligosaccharides in foods無色或白色晶體無色或白色晶體 乙醇乙醇 能被酵母發(fā)酵能被酵母發(fā)酵08-May-2143FWheat germWheat germ、pollenpollen、nectarnectar、tree honey tre

43、e honey and leafand leaf、stem and root of soybean.stem and root of soybean.FProduced by hydrolysis of starch using -Produced by hydrolysis of starch using -amylase.amylase.FAs nutrition and mild sweetener for foods.As nutrition and mild sweetener for foods.3.1 oligosaccharides in foods3.1 oligosacch

44、arides in foods主要分布在麥芽、花粉、花蜜、樹蜜及大豆植株的葉柄、莖和根部主要分布在麥芽、花粉、花蜜、樹蜜及大豆植株的葉柄、莖和根部 淀粉在淀粉在-淀粉酶的作用下分解，終產(chǎn)物是麥芽糖淀粉酶的作用下分解，終產(chǎn)物是麥芽糖08-May-21442 Lactose 2 Lactose P175,4.2.2P175,4.2.2F- pyranose galactose combined with - pyranose galactose combined with D-pyranose glucose by-1,4 glycoside.D-pyranose glucose by-1,4 g

45、lycoside.3.1 oligosaccharides in foods3.1 oligosaccharides in foods-吡喃半乳糖和吡喃半乳糖和D-D-吡喃葡萄糖吡喃葡萄糖以以-1-1，4 4糖苷鍵結(jié)合糖苷鍵結(jié)合 08-May-2145Fwhite or light yellow crystal;white or light yellow crystal;Flow solubility;low solubility;Ftiny sweet (1/6 of sucrose);tiny sweet (1/6 of sucrose);Freducing sugar;reducing

46、sugar;Fcow milk: 4.6-5.0%, human milk: 5-7%.cow milk: 4.6-5.0%, human milk: 5-7%.3.1 oligosaccharides in foods3.1 oligosaccharides in foods白色或乳黃色結(jié)晶白色或乳黃色結(jié)晶屬于還原性糖屬于還原性糖溶解度小溶解度小甜度也低甜度也低08-May-2146FLactose stimulates intestinal adsorption and Lactose stimulates intestinal adsorption and retention of ca

47、lciumretention of calcium（P175P175第二段第三行）第二段第三行） FD-glucose and D-galactose are rapidly D-glucose and D-galactose are rapidly absorbed and enter the blood streamabsorbed and enter the blood stream. . LactoseD-glucoseD-galactose+lactase3.1 oligosaccharides in foods3.1 oligosaccharides in foodsD-D-葡萄糖

48、和葡萄糖和D-D-半乳糖快速被吸收供血液利用。半乳糖快速被吸收供血液利用。 乳糖促進(jìn)腸道吸收和鈣的保留乳糖促進(jìn)腸道吸收和鈣的保留 08-May-2147FLactose intolerance:Lactose intolerance: the ingested lactose is the ingested lactose is only partially hydrolyzed, or is not only partially hydrolyzed, or is not hydrolyzed at all.hydrolyzed at all.FDeficiency of lactase r

49、esult in lactose Deficiency of lactase result in lactose remaining in the lumen of the small remaining in the lumen of the small intestine, producing abdominal distention intestine, producing abdominal distention and cramps.and cramps.3.1 oligosaccharides in foods3.1 oligosaccharides in foods乳糖不耐癥：某

50、種原因，攝入的乳糖僅部分乳糖不耐癥：某種原因，攝入的乳糖僅部分水解，即部分被消化，或不是全部水解水解，即部分被消化，或不是全部水解如果缺少乳糖酶，乳糖保留在小腸腸腔內(nèi)，由如果缺少乳糖酶，乳糖保留在小腸腸腔內(nèi)，由于滲透作用，乳糖有將液體引向腸腔的趨勢(shì)，于滲透作用，乳糖有將液體引向腸腔的趨勢(shì)，這種液體會(huì)產(chǎn)生腹脹和痙攣。這種液體會(huì)產(chǎn)生腹脹和痙攣。08-May-2148FThe presence or absence of lactase is under The presence or absence of lactase is under genetic control.genetic contr

51、ol.3.1 oligosaccharides in foods3.1 oligosaccharides in foodslactoseD-glucoseD-galactose+-galactosidase of bacteriaL-lactateFermentation by bacteria細(xì)菌細(xì)菌-半乳糖苷酶半乳糖苷酶 L-L-乳酸乳酸 08-May-2149FTwo ways to overcome lactose intoleranceTwo ways to overcome lactose intoleranceRemove the lactose by fermentation.

52、Remove the lactose by fermentation.Reduce lactose by adding lactase to it.Reduce lactose by adding lactase to it.FUsed in nourishment Used in nourishment 、dairy productsdairy products、firing products of infants.firing products of infants.3.1 oligosaccharides in foods3.1 oligosaccharides in foods二是加入

53、乳糖酶減少乳中乳糖。二是加入乳糖酶減少乳中乳糖。 一是通過發(fā)酵除去乳糖一是通過發(fā)酵除去乳糖08-May-21503 sucrose 3 sucrose P176,4.2.3P176,4.2.3F-D- -D- pyranose glucose combined with -pyranose glucose combined with -D-furan fructose by D-furan fructose by ,-1,2 glycoside.,-1,2 glycoside.-D-D-吡喃葡萄糖吡喃葡萄糖-D-D-呋喃果糖呋喃果糖123.1 oligosaccharides in foods

54、3.1 oligosaccharides in foods由一分子由一分子-D-D-吡喃葡萄糖和吡喃葡萄糖和一分子一分子-D-D-呋喃果糖通過呋喃果糖通過，-1-1，2 2糖苷鍵結(jié)合糖苷鍵結(jié)合 08-May-2151蔗糖很甜，易溶于水，比較難溶于乙醇蔗糖很甜，易溶于水，比較難溶于乙醇3.1 oligosaccharides in foods3.1 oligosaccharides in foods是一種非還原性糖。是一種非還原性糖。具有吸濕性和溶解性，很容易結(jié)晶；具有吸濕性和溶解性，很容易結(jié)晶；蔗糖具有右旋光性，蔗糖在水解后水溶液表現(xiàn)蔗糖具有右旋光性，蔗糖在水解后水溶液表現(xiàn)為左旋光性，因此蔗糖

55、水解液被稱為轉(zhuǎn)化糖。為左旋光性，因此蔗糖水解液被稱為轉(zhuǎn)化糖。 08-May-2152FUsed as sweeter.Used as sweeter.FAlso as preservatives and humectants. Also as preservatives and humectants. FIndwellIndwell fruit fruit、rootroot、stemstem、leafleaf、flower and seed of plants.flower and seed of plants.3.1 oligosaccharides in foods3.1 oligosac

56、charides in foods用作防腐劑和保濕劑用作防腐劑和保濕劑 存在于存在于08-May-2153Beet or sugarcanejuicecalcium salt+calcareousnessaqueous solutionfiltrate+active carbonreddish browncrystalVaporize、concentrate、coolingwhitecrystalgranulated sugarrock candyquickly coolingslowly cooling石灰石灰甜菜和甘蔗甜菜和甘蔗鈣鹽鈣鹽過濾過濾蔗糖水溶液蔗糖水溶液減壓蒸發(fā)，溶液經(jīng)過濃縮、冷

57、卻減壓蒸發(fā)，溶液經(jīng)過濃縮、冷卻活性碳活性碳砂糖砂糖冰糖冰糖08-May-21544 4 海藻糖（海藻糖（trehalose)trehalose)F鐔糖，鐔糖，屬于非還原型雙糖。屬于非還原型雙糖。F兩個(gè)吡喃葡萄糖分子以兩個(gè)吡喃葡萄糖分子以，-1,1-1,1鍵連接。鍵連接。3.1 oligosaccharides in foods3.1 oligosaccharides in foods08-May-2155F三種空間同分異構(gòu)體，構(gòu)成相應(yīng)的三種海三種空間同分異構(gòu)體，構(gòu)成相應(yīng)的三種海藻糖，分別稱為海藻糖（藻糖，分別稱為海藻糖（,-1,1鍵）、異鍵）、異海藻糖（海藻糖（,-1,1鍵）和新海藻糖（鍵）和

58、新海藻糖（,-1,1鍵）。鍵）。F存在于海藻、真菌、撅類、麥角等高等植存在于海藻、真菌、撅類、麥角等高等植物及酵母、無脊椎動(dòng)物及昆蟲的血液中。物及酵母、無脊椎動(dòng)物及昆蟲的血液中。3.1 oligosaccharides in foods3.1 oligosaccharides in foods08-May-2156F特殊的生物學(xué)功能：對(duì)特殊的生物學(xué)功能：對(duì)生物體組織和生物體組織和生物大分子具有生物大分子具有非特異性的保護(hù)作用非特異性的保護(hù)作用。保護(hù)蛋白質(zhì)、生物膜及敏感細(xì)胞的細(xì)胞保護(hù)蛋白質(zhì)、生物膜及敏感細(xì)胞的細(xì)胞避免受干旱、冷凍、滲透壓變化等造成避免受干旱、冷凍、滲透壓變化等造成的傷害；的傷害；

59、可用于工業(yè)上作不穩(wěn)定藥品、食品和化可用于工業(yè)上作不穩(wěn)定藥品、食品和化妝品的保護(hù)劑等。妝品的保護(hù)劑等。3.1 oligosaccharides in foods3.1 oligosaccharides in foods08-May-2157F機(jī)理有兩種假設(shè)機(jī)理有兩種假設(shè)F“水替代水替代”假說假說當(dāng)生物大分子失去維持其結(jié)構(gòu)和功能特當(dāng)生物大分子失去維持其結(jié)構(gòu)和功能特性的結(jié)構(gòu)水膜時(shí)，海藻糖能性的結(jié)構(gòu)水膜時(shí)，海藻糖能在生物分子在生物分子的失水部位以氫鍵的失水部位以氫鍵形式連結(jié)，形成一層形式連結(jié)，形成一層保護(hù)膜，以代替失去的水膜。保護(hù)膜，以代替失去的水膜。3.1 oligosaccharides in f

60、oods3.1 oligosaccharides in foods08-May-2158F“玻璃態(tài)玻璃態(tài)”假說假說通過海藻糖通過海藻糖玻璃化轉(zhuǎn)變玻璃化轉(zhuǎn)變的趨勢(shì)，導(dǎo)致無的趨勢(shì)，導(dǎo)致無定形連續(xù)相的形成，在結(jié)構(gòu)上與玻璃狀定形連續(xù)相的形成，在結(jié)構(gòu)上與玻璃狀的冰相似，在這種結(jié)構(gòu)中的冰相似，在這種結(jié)構(gòu)中分子運(yùn)動(dòng)和分分子運(yùn)動(dòng)和分子變性反應(yīng)非常微弱子變性反應(yīng)非常微弱。3.1 oligosaccharides in foods3.1 oligosaccharides in foods08-May-2159 棉籽糖（棉籽糖（raffinose)raffinose)F由由-D-D-吡喃半乳糖、吡喃半乳糖、-D-D