《食品化学》课程教学课件（国外讲稿）04 Carbohydrates part2

3/2/14 Degree of Sweetness Part Tw Sugar Relative degree of Sweetness Fructose 120 Glucose 70 Sucrose 100 Com Syrup 30-50 High-Fructose 80-90 Com Syrup 550.000,000Ibs,o Honey de hen Hunter of bees,Arana,Spain 7000 BCE The oldest written reference to the use of honey is thought to be Egyptian,of about 5500 BC.At that time Lower Egypt was called Bee Land while Upper Egypt was Reed Land

3/2/14& 1& Carbohydrates Part Two Degree&of&Sweetness& Sugar Relative degree of Sweetness Fructose 120 Glucose 70 Sucrose 100 Corn Syrup 30-50 High-Fructose Corn Syrup 80-90 Invert sugar syrup (Honey) 95 Honey& The oldest written reference to the use of honey is thought to be Egyptian, of about 5500 BC. At that time Lower Egypt was called Bee Land while Upper Egypt was Reed Land. Hunter of bees, Arana, Spain 7000 BCE

3/2/14 Sugarcane History Columbus took sugarcanes to http://en.wikipedia.org/wiki/History of sugar (optional) the Americas New Giuinea people were probably first to domesticate sugareane Crusaders brought sugarcane cultivation to Europe The Spanish and Portuguese started sugar cane growth and production in the Americas The English,Dutch and French latter became involved in the large scale production of sugar as well Sugar trade source of great wealth for Britain and the Dutch The British and Dutch ser 。Average cons ol ith r 4 pounds in 1700 Suar collapsed in the 1800s 1s pounds in 1800 Low prices due to competition from beet suga 36 pounds in 1850 100 pounds in 100

3/2/14& 2& Sugarcane History http://en.wikipedia.org/wiki/History_of_sugar (optional) • New Guinea people were probably first to domesticate sugarcane • India people discovered how to crystallize sugar 400 BC • Sugarcane technology latter carried to China and Arabia • Crusaders brought sugarcane cultivation to Europe Columbus took sugarcanes to the Americas • The Spanish and Portuguese started sugar cane growth and production in the Americas • The English, Dutch and French latter became involved in the large scale production of sugar as well • Average&consump;on& per&person&in&Britain&& increase&from&& &&&4&pounds&in&1700&& &18&pounds&in&1800& && &36&pounds&in&1850&& 100&pounds&in&1900& Sugar trade source of great wealth for Britain and the Dutch (jams, candy, tea, coffee, cocoa, processed foods, and other sweet foods) The British and Dutch sent all exports of manufactured goods to their colonies in their ships and the ships returned with rum and sugar Sugar cane trading collapsed in the 1800s Low prices due to competition from beet sugar Emancipation and end of slave trade (1830 in England)

3/2/14 Carbohydrates -Refined Sugar Sugar Beets Sucrose:common chemical name -The development of the European beet White table sugar:sucrose sugar industry was encouraged by the Napoleonic Wars.In 1807 the British began a Only taste is sweetness blockade of France that prevented the import of sugarcane from the Caribbean. Uniform quality (99.99+%purity) .In 1813 Napoleon instituted a retaliatory Source of nutritive energy embargo.By the end of the wars.over 300 ·“Empty calories'"? sugar beet mills operated in France and central Europe. .Beet sugar accounts for 30%of the world's sugar production. Corn Syrup Corn Syrup HFCS 1970's A much cheaper sweetener obtained from hydrolysis of(corn)starches. It is used as a thickener,sweetener,and for its High Fructose Corn Syrups(HFCS) moisture-retaining (humectants)properties which keep foods moist and help to maintain freshness. The more Fructose the sweeter the corn syrup! Most HFCS's are about 50%glucose 50%fructose,i.e.equivalent to sucrose(??)

3/2/14& 3& Carbohydrates& H&Refined&Sugar& • Sucrose:&&common&chemical&name& • White&table&sugar:&&sucrose& • Only&taste&is&sweetness& • Uniform&quality&(99.99+&%&purity)& • Source&of&nutri;ve&energy& • Empty&calories?& Sugar&Beets& •The development of the European beet sugar industry was encouraged by the Napoleonic Wars. In 1807 the British began a blockade of France that prevented the import of sugarcane from the Caribbean. •In 1813 Napoleon instituted a retaliatory embargo. By the end of the wars, over 300 sugar beet mills operated in France and central Europe. •Beet sugar accounts for 30% of the world's sugar production. Corn&Syrup& 1970’s& • A&much&cheaper&sweetener&obtained&from&hydrolysis& of&(corn)&starches.& • It is used as a thickener, sweetener, and for its moisture-retaining (humectants) properties which keep foods moist and help to maintain freshness. Corn&Syrup&&&HFCS& • Ordinary&corn&syrup&(glucose&solu;on)&can&be&treated& with&enzymes&to&produce:& • High&Fructose&Corn&Syrups&(HFCS)& • The&more&Fructose&the&sweeter&the&corn&syrup!& • Most&HFCS’s&are&about&50%&glucose&&&& 50%&fructose,&i.e.&equivalent&to&sucrose&(??)& G" F"

3/2/14 HIGH Intensity Sweeteners 100-25,000 times sweeter than sucrose,two groups Artificial,chemically synthesized sweeteners 7 Natural high intensity sweeteners are extracted from various plants Common Artificial Sweeteners Properties Approved Low Calorie Sweeteners eetene spartame ess with heat 180 times .Acesulfame potassium (sunett and Sweet one) nine and aspartic acid ·Aspartame Saccharin 300 times Neotame(made by NutraSweet) e stable 200 times ·Saccharin ste Synergistic sweetening effect with ·Sucralose(Splenda) other sweeteners Sucralose 600 times eotame 6000 times 罄

3/2/14& 4& HIGH&Intensity&Sweeteners& • 100H25,000&;mes&sweeter&than&sucrose,&two& groups& • Ar;ficial,&chemically&synthesized&sweeteners& • Natural&high&intensity&sweeteners&are&extracted& from&various&plants& Common&Ar;ficial&Sweeteners& Sweetener Properties Sweetness Compared to Sucrose Aspartame Loses its sweetness with heat Made of 2 amino acids, phenylalanine and aspartic acid 180 times Saccharin Heat-stable Bitter metallic aftertaste 300 times Acesulfame Heat stable Slight aftertaste Synergistic sweetening effect with other sweeteners 200 times Sucralose Extremely stable Packaged with maltodextrin 600 times Neotame New sweetener approved in 2002 in USA 6000 times Approved&Low&Calorie&Sweeteners& • Acesulfame&potassium&(Sunett and Sweet One)& • Aspartame& • Neotame&(made&by&NutraSweet)& • Saccharin& • Sucralose&(Splenda)& 8 oz Calories 100 Total Fat (g) 0 Sodium (mg) 20 Potassium (mg) 10 Total Carbohydrates (g) 28 Sugars (g) 28 Protein (g) 0 Caffeine (mg) 25 8 oz Calories 0 Total Fat (g) 0 Sodium (mg) 25 Potassium (mg) 20 Total Carbohydrates (g) 0 Sugars (g) 0 Protein (g) 0 Caffeine (mg) 24

3/2/14 Saccharin (oldest) Saccharin Safety 1,2-benzisothiazol-3(2H)-one-1,1-dioxide House Votes to Del The Saccharin Ban 300X sweetness of sucrose can be One commercial name is"Sweet 'n Low' 0 use NH 50 NH Sucralose Aspartame(NutraSweetTM) .Sucralose:trade name,Splenda,is 600 X sweeter than sugar al amino acigl -FDA approved it in 1998 as a tabletop sweetener and now FDA amended its regulation to allow sucralose as a general-purpose sweetener for all foods. -Sucralose tastes like sugar because it is made from table sugar.But it cannot be digested,so it adds no calories to food

3/2/14& 5& SO2 NH O Saccharin&(oldest) • 1,2HbenzisothiazolH3(2H)HoneH1,1Hdioxide& • 300X&sweetness&of&sucrose& • One&commercial&name&is&Sweet&
n&Low SO2 NH O Saccharin&Safety • For&many&years,&saccharin&was& declared&a&carcinogen&—&and&it& can&be&.& • However,&finally&in&2000,&the&FDA& declared&it&was&not&
officially&a& carcinogen&and&thus&is&legal&to& use& Aspartame&(NutraSweet™)& • Aspar;c&acid&(a&natural&amino&acid)& • Phenylalanine&(a&natural&amino&acid)& – Poten;al&problem&with&phenylketonuria &disorder& (PKU)& – Label&must&give&warning:& • Phenylketonurics:&contains& phenylalanine& • Esterified&with&methanol&(methyl& alcohol)& – Thus&this&compound&is&synthe;c&and&does&not& exist&in&nature& • 200x&sweeter&than&sucrose& Sucralose • Sucralose:&trade&name,&Splenda,&is&600&X&sweeter&than&sugar.& – FDA&approved&it&in&1998&as&a&tabletop&sweetener&and&now& FDA&amended&its&regula;on&to&allow&sucralose&as&a& generalHpurpose&sweetener&for&all&foods.& – Sucralose&tastes&like&sugar&because&it&is&made&from&table& sugar.&But&it&cannot&be&digested,&so&it&adds&no&calories&to& food.&

3/2/14 Alitame kt. zero Relative Sweetness:2,000 times sweeter than sucrose. con for amee in bo has the U Co隐 AM Other Naturally-Occurring sweeteners being studied ww.dielco (000 -Steva accounts for nearly 40%of the 6

3/2/14& 6& Alitame& • Descrip+on:&Discovered&by&Pfizer,&Inc.,&alitame&(brand&name&Aclame™&)&is&a& sweetener&formed&from&the&amino&acids&LHaspar;c&acid&and&DHalanine,&and&a& novel&amine.& • Rela+ve"Sweetness:&2,000&;mes&sweeter&than&sucrose.&& • Status:&A&pe;;on&for&alitame's&use&in&a&broad&range&of&foods&and&beverages&has& been&filed&in&the&U.S.&Alitame&is&approved&for&use&in&a&variety&of&food&and& beverage&products&in&Australia,&New&Zealand,&Mexico&and&the&Peoples& Republic&of&China.&Approval&also&is&being&sought&worldwide.& Acesulfame K is often blended with other sweeteners (usually sucralose or aspartame). These blends are reputed to give a more sugar-like taste whereby each sweetener masks the other's aftertaste, and/or exhibits a synergistic effect by which the blend is sweeter than its components. Other&NaturallyHOccurring&sweeteners& being&studied& • stevioside&or&stevia& • (200H250x)& – Extracted&from&plants&growing&in&Brazil&&& Argen;na& – Stevia&accounts&for&nearly&40%&of&the& sweetener&market&in&Japan&and&is&commonly& used&in&various&parts&of&South&America.&

3/2/14 GRAS Good& GRAS Generally Regarded Sweet as Safe 90 REB-A 99% op5 ifewate SWEETENE e27 tenmmanher More Complex carbohydrate reactions Stevia. According to reports in the Wall Street Joumal,Coca-Cola has fled 24 patent applications for the product,which has been zero carbohydrates and a zero glycemic index". >

3/2/14& 7& GRAS Generally Regarded as Safe Agribusiness Cargill has teamed up with Coca-Cola to market a new calorie-free natural sweetener made from the South American herb Stevia. • According to reports in the Wall Street Journal, Coca-Cola has filed 24 patent applications for the product, which has been tentatively named Rebiana. It plans to use the sweetener in some of its beverages. • Stevia is a member of the daisy family, and the extract is claimed to be "the world's only all-natural sweetener with zero calories, zero carbohydrates and a zero glycemic index". More&Complex&carbohydrate&reac;ons&

3/2/14 Epimerizations Aldose and aldose-ketose isomerizations C=0 enolization H一C=0 -OH HO- HO- R A solution of D-glucose in 0.035%NaOH at 35C For 100 hr gives a mixture of H-C-OH HO- H D-Fructose ()D-Mannose and D-Glucose(57) -OH -OH HO一H HO- -H Lobry de Bruyn-van Ekenstcin reaction R Enediol Famous reactions Elimination(stronger base) fernema's food Chemnt via enediol H。 H-C-OM HO-CH C-OH H C-H H-C-OH H-C-OH keto-enol enok-keto ep-gucose 8

3/2/14& 8& Epimerizations and aldose-ketose isomerizations A solution of D-glucose in 0.035% NaOH at 35 °C For 100 hr gives a mixture of D-Fructose (28%), D-Mannose (3%) and D-Glucose (57%) Lobry de Bruyn-van Ekenstein reaction enoliza;on Famous reactions Elimination (stronger base) via enediol keto-enol C C C C R O OH HO H H H OH H C C C C R OH HO H H OH H OH C C C C R O OH H H OH H C C C C R O O H H OH H elimination enol-keto e.g., D-glucose 2-keto-3-deoxy-D-glucose (3-deoxy-D-glucosulose)

3/2/14 Famous reactions More concentrated basicsolution sugars into variou types o +ON H-C-0 g=0 HO- H-H 27teo6g8026 + OH 军 HC-OH H一H Famous reactions HMF and related compounds strong acid or base heating at low pH 5-nydoyra e) HMF can be found many foods which heve been heated in acid tcoribedasaeasure ofeofheaing Further heaing produces colored,aed polymers

3/2/14& 9& 2-keto-3-deoxy-D-glucose (3-deoxy-D-glucosulose) Famous reactions Elimination (stronger base) More&concentrated&basic&solu;ons&convert&sugars&into&various& types&of&saccharinic&acids& Famous reactions strong acid or base In Base heating gives flavors and odors (aroma) small, relatively volatile compounds In Acid (more common in foods) colored polymers - yellow & brown continued dehydration (previous slide) C C C C C O O H H OH H H C H2OH H OH C C C C C O O H H H C H2OH H OH O C H O OH H2C OH H O C H O H2C OH 5-(hydroxymethyl)-furfural HMF HMF and related compounds heating at low pH •HMF can be found many foods which have been heated in acid •Its concentration can be used as a measure of the extent of heating •Try the elimination, cyclization and further dehydration beginning with D-fructose. Note that the first double bond could be between C2 and either C1 or C3. •Further heating produces colored, conjugated polymers 5-(hydroxymethyl)-furfural HMF O C H O H2C OH

3/2/14 D- 毛 3-deaxy-glucosulose 毛 D-Fructose 2.3enedio 20 inacid solutions D-Glucese 3deoy D-Fructose 1-deoxy -deaxy&4-deoxy 10

3/2/14& 10& D-Glucose 3-deoxy-glucosulose C H OH HO H H OH H OH CH2OH H O C OH HO H H OH H OH CH2OH H OH C OH H H OH H OH CH2OH H O C O H H OH H OH CH2OH H O elimination -2H2O CH2 O C H HO O HMF H CH2OH O HO H H OH H OH CH2OH HC OH HO H H OH H OH CH2OH CH2OH OH HO H OH H OH CH2OH OH OR CH2OH OH HO H OH H OH CH2OH CH2OH O HO H H OH CH2OH CH2 OH O H OH H OH CH2OH OR 1,2 enediol 2,3 enediol 2,3 enediol elimination -H2O D-Fructose CH2OH O HO H H OH CH2OH CH2 OH O H OH H OH CH2OH CH3 O O H OH H OH CH2OH CH2OH O O H H OH CH2OH H O CH2OH OC O OH OC H3C O O OH CH3 -2H2O -2H2O 1-deoxy-2-3-diketose 4-deoxy-2-3-diketose D-Glucose 3-deoxy D-Fructose 1-deoxy, 3-deoxy, & 4-deoxy In acid solutions