Question

(a) Sorbitol and mannitol are produced from the addition of H2 to the carbonyl group of fructose. Draw the Fischer projections of fructose, sorbitol AND mannitol. Give a brief description of the use of polyols in the food industry. (b) Describe how starch hydrolysis is used in the food industry. Include a definition of the terms “Dextrose Equivalent” AND “Degree of Polymerization”. (c) Discuss the use of vacuum pans in the controlled crystallization of sucrose in a sugar refinery. Ensure to include the concepts of solubility, temperature, vapour pressure and evaporative cooling. (d) The beta glucans are an important class of polysaccharide. Describe their structure (in words) and how they are considered to influence postprandial serum glucose levels. (e) Discuss the behaviour of water in two component systems such as packaged cereals containing raisins and cornflakes. Include the role that glycerol could play in this type of product.

Answer 1

Degree of polymerization: It is quite opposite to D. E Valu It is the number of monomers polymerized y more degree of polymerization meany more monomer are participated in polymerization to give a gaint molecule. number of monomens polymerized number of monomen umpolymerized

CH₂olt сн, он -о-о (нс - он, Но — с - Ін но - с - н SORBITOL нс - он н - с -он H-c-oh 4 - с - он MANNITOL CHLOH сн. Он D-FRUCTOSE ch-o4 T но - с - 4 но – с 4 - П-- of и-с-он и-с-он o FISCHER PROJECTIONS сон сов ch -он - он чоти кон SORBITOL the * Hoa LH -1 -он MANNITOL Сон FRUCTOSE сон сон Но — Н осно у нь он HHOH CHOH

Degree 과 It is more mo to a 6 starch is a poly Saccharide means it is made up of many Saccharichs - It is just like a polymer made up of many small anis see saccharides - lu Food industries during hydrolysis these poly saccharidhs are made into smaller anits like mono Saccharides Di Saccharides oligo Saccharider ete which are smaller units of starch had These are easily soluble in water Sweeter to taste and have good calarific value Hence there mono & di Saccharides au very much usefull in food industry (DE) Dextrose Equivalent voluce is used to indicate the degree of a Hydrolysis 7 It is % do the total solids that have been converted to Reducing sugars Higher the DE value, inclicati more Sugares and less dextrins - 55 D.E is generally termed as High Convertia