2009_Book_FoodChemistry

330 4 Carbohydrates
Table 4.27. Utilization of cellulose derivatives (in amounts of 0.01 to 0.8%)
Food product Cellulose derivative a Effect
1 2 3 A b B C D E F G H I
Baked products + + + + +
Potato products + + + + +
Meat and fish + + + + +
Mayonnaise, dressings + + + + +
Fruit jellies + + + +
Fruit juices + +
Brewery + + + +
Wine + + + +
Ice cream, cookies + + + +
Diet food + + + +
a 1: Carboxymethyl cellulose, Na-salt; 2: methyl cellulose; 3: hydroxypropyl methyl cellulose.
b A: Thickening effect; B: water binding/holding; C: cold gel setting; D: gel setting at higher
temperatures; E: emulsifier; F: suspending effect; G: surface activity; H: adsorption; and I: filmforming
property.
The properties of the product depend on the
degree of substitution (DS; 0.3–0.9) and of
polymerization (DP; 500–2000). Low substitution
types (DS ≤0.3) are insoluble in water but
soluble in alkali, whereas higher DS types (>0.4)
are water soluble. Solubility and viscosity are
dependent on pH.
Carboxymethyl cellulose is an inert binding
and thickening agent used to adjust or improve
the texture of many food products, such as
jellies, paste fillings, spreadable process cheeses,
salad dressings and cake fillings and icings
(Table 4.27). It retards ice crystal formation in ice
cream, stabilizing the smooth and soft texture.
It retards undesired saccharose crystallization
in candy manufacturing and inhibits starch
retrogradation or the undesired staling in baked
goods. Lastly, Carboxymethyl cellulose improves
the stability and rehydration characteristics of
many dehydrated food products.
4.4.4.18 Hemicelluloses
The term hemicelluloses refers to substances
which occupy the spaces between the cellulose
fibrils within the cell walls of plants. Various
studies, e. g., on apples, potatoes, and beans,
show that xyloglucans dominate in the class
Dicotyledoneae. A section of the structure of
a xyloglucan from runner beans is presented in
Formula 4.161.
In the class Monocotyledoneae, the composition
of the hemicelluloses in the endosperm tissue
varies greatly, e. g., wheat and rye contain mainly
arabinoxylans (pentosans, cf. 15.2.4.2.1), while
β-glucans (cf. 15.2.4.2.2) predominate in barley
and oats.
(4.161)