Do not duplicate High-intensity Sweeteners, Polyols, and Non-chemical Modifications of Starch Yuan Yao Whistler Center for Carbohydrate Research October 3, 2017 Do not duplicate Sweetness Sweetness • Hypothesis: sweetness perception is initiated by an interaction of a sweet molecule with a receptor site in the taste buds • The actual receptor site has not been isolated • Once a sweet molecule interacts with the receptor site, a series of reactions occurs and the taste signal is sent to brain • Various models have been proposed, and the most widely accepted one is the three-point attachment theory (AH-B-X) • Relationship between chemical structure and the ability to initiate sweetness is not well understood • Most sweeteners were discovered by trial and error Do not duplicate Sweetness http://www.elmhurst.edu/~chm/vchembook/549receptor.html • AH+ area contains functional groups with hydrogen to form hydrogen bond with partially negative atom on the sweet molecule (acid group COO- on aspartame) • B- area contains partially negative groups available to form hydrogen bond with hydrogen on the sweet molecule (amine group NH3+ on aspartame) • X area is a hydrophobic (lipophilic) area interacting with the non-polar area on the sweet molecule (benzene ring on aspartame) Do not duplicate Sweeteners High intensity sweeteners Acesulfame K Alitame Aspartame Cyclamate Neotame Saccharin Steviol glycoside Sucralose Mogroside V Polyols Erythritol Isomalt Hydrogenated starch hydrolysates maltitol Lactitol Sorbitol Mannitol Xylitol Do not duplicate High Intensity Sweeteners Acesulfame K (200 X sugar sweetness) •5,6-dimethyl-1,2,3-oxathiazine-4(3H)-one 2,2- dioxide, a sweet tasting compound, was incidentally discovered in 1967 by Clauss and Jensen •Among different substitutions, 6-methyl- 1,2,3-oxathiazine-4(3H)-one 2,2-dioxide was demonstrated to be the most favorable one •Generic name acesulfame potassium was registered by the world Health organization (WHO) •Acesulfame K is a white crystalline powder, dissolving readily in water http://www.elmhurst.edu/~chm/vchembook/549 acesulfame.html • “The additive shall be used in accordance with current good manufacturing practice in an amount not to exceed that reasonably required to accomplish the intended effect” (FDA 21CFR172.800) • Applications: low-calorie products, diabetic foods, sugarless products, oral hygiene preparations, pharmaceuticals, and animal feeds Do not duplicate High Intensity Sweeteners Aspartame (160 - 220 X) • 1-methyl N-L-[alpha]-aspartyl-L- phenylalanine, a dipeptide containing L- aspartic acid and the methyl ester of L- phenylalanine • Incidentally discovered in 1965 by GD Searle and James Schlatter • Under certain conditions, the ester bond is hydrolyzed, forming methanol and dipeptide, which is ultimately hydrolyzed to individual amino acids • Maximum stability at around pH 4.3. Very high temperature reduces stability http://www.elmhurst.edu/~chm/vchembook/549 aspartame.html • Slightly soluble in water (~1.0%) • The label of any food containing the additive shall bear: Phenylketonurics: Contains Phenylalanine. When the additive is used in a sugar substitute for table use, its label shall bear instructions not to use in cooking or baking (21CFR172.804) Do not duplicate High Intensity Sweeteners Sucralose (600 X) (Splenda) • 1,6-dichloro-1,6-dideoxy-[beta]-D- fructofuranosyl-4-chloro-4-deoxy-[alpha]- D-galactopyranoside • Discovered in 1970s by Hough and his coworkers, with the support of Tate & Lyle • Selective chlorination of sucrose • A white, crystalline, nonhydroscopic powder • Highly soluble in water and ethanol • Dry sucralose may show increased discoloration at higher temperature • Sucralose liquid concentrates show high http://www.elmhurst.edu/~chm/vchembook/549 storage stability sucralose.html • The additive may be used as a sweetener in foods generally, in accordance with current good manufacturing practice in an amount not to exceed that reasonably required to accomplish the intended effect (21CFR172.831) Do not duplicate High Intensity Sweeteners Steviol glycosides (30-300 X) • Steviol: (5β,8α,9β,10α,13α)-13- Hydroxykaur-16-en-18-oic acid • Found in S. rebaudiana, with stevioside (120 X) most abundant, followed by rebaudioside A (250 X, better tasting) • Reb-A: stable at pH 4-8, with reduced stability in more acidic systems; stable Steviol structure. Steviol is the aglycone to steviol with common thermal treatment: retorting, glycosides (Different units at R1 and R2) (J.M.C. UHT, pasteurization; lasting sweetness Geuns, 2003, Phytochemistry 64: 913–921) perceived longer than sucrose Compound R1 R2 Stevioside -glc- -glc--glc- Rebaudioside A -glc- (-glc)2--glc- Rebaudioside B H (-glc)2--glc- Rebaudioside C -glc- (-glc-, -rha-)--glc- Rebaudioside D -glc--glc- (-glc)2--glc- http://dalberg.com/blog/wp- content/uploads/2011/08/Peru-2010-067.jpg Do not duplicate High Intensity Sweeteners Mogroside V (250-400 X) • Luo Han Guo (LHG, Siraitia grosvenorii ) has been used in Asia as medical herbs and teas • LHG contains a number of mogrosides (mogrol glycosides), such as mogroside III, mogroside V, mogroside VI, mogroside IIE, mogroside IIIE, neomogroside, siamenside I, and 11-oxo- http://www.sanherb.com/products/corsvenor-momordica- fruit/luo_han_guo_extract.html mogroside V • Primary sweet component is Mogroside V o GRAS for LHG fruit extracts containing mogroside V o Thermally stable (UHT, retorting) o Stable at pH 3-7 • LHG extracts can be used in combination with others, e.g. http://www.scbt.com/datasheet- 280990-mogroside-v.html rebaudioside A, to offer a more balanced taste profile o Reb-A: quick onset Structure of Mogroside V: 5 glucosyl units attaching to the aglycone mogrol o LHG: slower build Do not duplicate Polyols • Definition and natural occurrence • Structure and manufacture • Physicochemical and organoleptic properties • Nutritive value and health benefit • Applications Do not duplicate Definition and Natural Occurrence What are polyols? Are they natural? Definition • “Sugar alcohol” and “polyol” are synonyms • Carbonyl group (>C=O) in the aldose and ketose moieties of mono-, di-, oligo-, and polysaccharides is replaced by alcohol group (>CH-OH) • Polyols generally carry the suffix ‘itol’ in place of the suffix ‘ose’ Natural occurrence Polyol Natural occurrence Erythritol Wine, sake, soy sauce, melons, pears, grapes, etc. Xylitol Fruit, vegetables, intermediate in glucose metabolism Sorbitol Rowan, pears, cherries, plums, apricots, apples, etc. Mannitol Tree exudates, manna ash, marine algae, fresh mushroom Maltitol Lactitol Isomalt Polyglycitol Do not duplicate Molecular Structure Structures of polyols are similar: Carbonyl group is replaced by alcohol group CH2OH CH2OH CH2OH CH2OH O OH OH OH OH Maltitol OH CH2OH HO O HO OH OH OH OH CH2OH CH OH OH 2 OH Erythritol CH2OH Lactitol CH2OH OH CH OH OH O 2 Sorbitol O OH OH CH2OH CH2OH CH2OH OH CH2OH OH HO HO OH HO HO HO HO OH CH OH CH2OH OH 2 OH OH OH O O OH OH CH OH 2 OH OH CH2OH O O Xylitol HO HO Mannitol OH OH Isomalt: 50%GPM + 50% GPS Do not duplicate Industrial Manufacturing Polyols industry is established Starch Xylan Lactose Sucrose Liquefaction Hydrolyzation Enzymatic conversion Saccharification Isomaltulose Fermentation Hydrogenation Hydrogenation Hydrogenation Hydrogenation Purification Purification Purification Purification Purification Erythritol Sorbitol Xylitol Lactitol Isomalt Mannitol Maltitol Polyglycitol Do not duplicate Physicochemical Properties Polyols have diversified properties Solubility Melting Hygro- Heat stability Acid stability Polyol/sugar g/100g H O point (°C) scopicity 2 (°C) (pH) (25°C) Erythritol 126 Very low 37-43 >160 2-12 Xylitol 94 High 63 >160 2-10 Mannitol 165 Very low 18-22 >160 2-10 Sorbitol 97 Median 70-75 >160 2-10 Maltitol 150 Median 60-65 >160 2-10 Isomalt 145-150 Very low 25-28 >160 2-10 Lactitol 122 Low 55-57 >160 >3 Hydrolyzes at Sucrose 190 Low 67 <160-186 acidic/alkaline pH Modified: L. Nabors. Alternative Sweeteners. Third edition, 2001, Marcel Dekker, Inc, NY Do not duplicate Organoleptic Properties Polyols are sweet and cool Sweetness Compared with Sucrose 100 80 60 40 20 0 Erythritol Xylitol Sorbitol Mannitol Maltitol Isomalt Lactitol Sucrose Sweetness 65 100 60 50 90 40 35 100 Cooling Effect 0 -10 -20 -30 -40 -50 Erythritol Xylitol Sorbitol Mannitol Maltitol Isomalt Lactitol Sucrose Heat of Solution (cal/g) -42.9 -36.6 -26.5 -28.9 -5.5 -9.4 -13.9 -4.3 Do not duplicate In the Gastrointestinal Tract Polyols are not fully digested in the body Carbohydrate Not metabolized Kidneys Urine Absorbed Small intestine Metabolized Not Energy absorbed CO2 Volatile fatty acids Fermented Large intestine CH4/H2 Not Biomass fermented Feces Feces Do not duplicate Glycemic Response Polyols are low in glycemic response Glucose Xylitol Sucrose Sorbitol Maltitol Isomalt Erythritol Lactitol Mannitol Glycemic curves for glucose, sucrose, maltitol, isomalt, lactitol, xylitol, sorbitol, erythritol, and mannitol in normal individuals. Data from several publications were pooled to yield curves representative of 25 g doses (20–64 g for erythritol) (Adapted from G. Livesey. Nutrition Research Reviews. 2003, 16, 163 –191) Do not duplicate Colon Health Polyols are beneficial to colon health • Fermented by microflora, polyols benefit colon health • Enables saccharolytic anaerobes and aciduric organisms to grow in preference over putrefying, endotoxic, pathogenic, and procarcinogen-activating aerobic organism • Acidic conditions may normalize epithelial functions • Lactic acid is generated