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Lecture II Ring Forms, Glycosides

Lecture II Ring Forms, Glycosides. Indredients: NaAlginate; CaCl 2 ; Color; ground glass; sucrose; bakers’ yeast. Carbohydrate Structure III. Monosaccharides Important ones D-glyceraldehyde source Straight chain does not explain all Rxs Ring formation Mutarotation Haworth projection.

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Lecture II Ring Forms, Glycosides

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  1. Lecture IIRing Forms, Glycosides Indredients: NaAlginate; CaCl2; Color; ground glass; sucrose; bakers’ yeast.

  2. Carbohydrate Structure III • Monosaccharides • Important ones • D-glyceraldehyde source • Straight chain does not explain all Rxs • Ring formation • Mutarotation • Haworth projection

  3. OCH3 H C OH HOCH3 + R OCH3 H C OCH3 H2O + “Full” Acetal R CH3OH .. H C O Hemiacetal R RING FORMATION

  4. H 5 C O 1 CH2OH C 4 OH C OH 2 C H C O OH 2 C 1 OH 3 HO C C C OH 3 4 OH C OH 5 CH2OH 6 CH2OH 6 6 CH2OH O 5 5 H C O : 4 OH 1 4 OH C H C 2 OH 2 OH 1 HO C C 3 OH 3 OH RING FORMATION 6 O Fig 3.7, p 88

  5. 6 4 5 2 1 3 b -D-glucopyranose Fig 3.11, p 90

  6. CH2OH C OH 6 O C OH 5 C OH 1 4 OH 2 OH C OH OH 3 OH C Glucose Anomers: HemiacetalsReducing sugars Mutarotate Ring opens here - Mutarotation 1 2 O 3 4 5 CH2OH 6 a-D-Glucose (m.p. 146o, [a] = +112o) or Equilb = 53o Fischer projection of hemiacetal ring b-D-Glucose (m.p. 150o, [a] = +19o)

  7. Glucose Equilibrium Cpds Fig 3.12, p 91 a-D-glucopyranose a-D-glucofuranose 0.003% D-glucose (aldehydo-D-glucose) b-D-glucopyranose b-D-glucofuranose Possible isomers of D-glucose in aqueous solution

  8. CH2OH 6 D- 5 O L- { a (L-) b (D-) 1 4 { OH a (D-) b (L-) OH 3 2 OH OH HAWORTH PROJECTION * a-D-GLUCOSE (a-D-Glucopyranose)

  9. O OH OH 4 1 HOH2C 2 5 3 OH The Furanose Ring a-L-Arabinofuranose

  10. O O C-5 EPIMERS L-GULOSE D-MANNOSE CH2OH O O CH2OH = = OH OH OH OH OH OH Epimers = Stereoisomers differing in position of -OH groups at only one asymmetric carbon (in this case, at C-5)

  11. O OH C O CH2OH O o OH OH OH CH2OH OH C OH O O b-L-Galactopyranose/furanose

  12. 6 2 1 5 4 3 C-5 EPIMERS - Effect of bulky group b-D-Mannopyranosyluronic acid unit, 4C1 Conformation

  13. C-5 EPIMERS - Effect of bulky group 5 6 1 4 3 2 a-L-Gulopyranosyluronic acid unit - 1C4 conformation

  14. Carbohydrate Structure IV • Glycosides • Alcohol + acid, - H2O • Physiological function • Base stable, acid labile • Rx with other sugars

  15. aglycon CH2OH O H+ + H2O + ROH OR OH OH “Full” acetal linkage OH alkyl D-glucopyranoside Glycosides Hemiacetal linkage CH2OH O OH OH OH OH D-glucose (D-glucopyranose)

  16. Function of Simple CHOs in Foods I • Reactions with other Ingredients • Water (hydrophilicity) • Flavors • Sweeteners • Alcohols • Bulking Agents

  17. Sugar Alcohols; Sweetness

  18. Function of Simple CHOs in Foods II • Bulking Agents • Maltodextrins (DE < 20) • Maltrin MO40 – from corn • Instant N-Oil – from tapioca • Paselli SA1 – from potato • Oatrim – from oat bran & flour • Polydextrose (to be covered later)

  19. NONFAT, NO SUGAR ADDED, SOFT SERVE ICE CREAM WITH PRIMACEL FOOD CELLULOSE PRODUCT, SIMPLESSE* 500 AND NUTRASWEET* CUSTOM LIQUID 50 PRODUCT FORMULATION SS-7822 This formulation contains 27.5% total solids, 13.4% MSNF, 0.59% fat and no added sugars. There is <0.5 g of fat per 80 g serving, qualifying the formulation for the nonfat descriptor. This product is a good clean base for a variety of flavors including vanilla. QUANTITY INGREDIENTS GRAMS PERCENT Skim milk 787.35 78.735 NEOSORB P60 sorbitol (Roquette) 50.00 5.000 LITESSE polydextrose (Cultor) 50.00 5.000 Milk solids, nonfat 40.00 4.000 M180 maltodextrin (GPC) 40.00 4.000 SIMPLESSE 500 mircoparticulated whey protein concentrate 20.00 2.000 Cream, 40% butterfat 8.00 0.800 PrimaCel food cellulose product1.50 0.150 NUTRASWEET Custom Liquid 50 1.40 0.140 DM Freeze 75K emulsifier blend 1.00 0.100 Cellulose gum, 99-7HF (Hercules) 0.75 0.075 Flavoring to suit to suit -------- --------- 1000.00 g 100.00 %

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