Food Emulsifiers and Stabilizers - Food Shelf Life Stability: Chemical, Biochemical, and Microbiological Changes - page 236

a soft white solid (triglyceride monopalmitate) to hard white beads (hexaglycerol
dipalmitate and hexaglyceryl distearate) to a pale yellow liquid (decaglycerol
dioleate). When these compounds were tested as emulsifiers in dessert toppings,
results showed markedly superior organoleptic qualities, improved color character-
istics, and enhanced emulsifying characteristics. Furthermore, the hexaglycerol dis-
tearate outperformed all other emulsifiers (including sorbitan monostearate and
polysorbate 60) tested. 142-145
Sucrose Esters (SE)
Sucrose esters, particularly mono- and diesters, are potentially very valuable emul-
sifiers and as such offer a number of unique advantages. They are non-toxic, odorless,
tastless, non-irritating to the skin, and easily digested. They are biodegradable under
both aerobic and anaerobic conditions, and unlike most other non-ionic surfactants
they are normally solids, and may be used as powdered or spray-dried products. SEs
have a chemical structure that is found in many of the typical emulsifiers, i.e., both
polar and nonpolar groups in the same molecule. Since there are eight possible
positions that can be esterified with fatty acids, the final product offers a wide range
in HLB values, from one extreme (lipophilic HLB value of 1) to another (hydrophilic
HLB values of 20). 145
SEs compounds, formed from the reaction between sucrose and methyl esters
of fatty acids, are used extensively in foods. 145,146 They are used in cakes, cookies,
and breads; as emulsified oils and fats in coffee whiteners, whipped cream, recom-
bined milk, shortening oil, ice cream, low calorie margarine; in instant foods such
as curry, soybean curd, cocoa, and cake mixes; for confectionery use in biscuits,
chocolate, chewing gum, rice cakes, and tablet candy; and for preventing starch
retrogradation. One of the recent uses of SEs is as a low-calorie, cholesterol-free
fat substitute. Sucrose polyesters have been reported to have a fat content of zero
calories and an ability to lower cholesterol levels. If so, then these products could
be used as a home-cooking oil as well as for making salted snacks, such as potato
chips. They could also be used as cooking oils in restaurants and in the fast food
industry as deep frying oils. Other food products that could benefit are ice cream,
mayonnaise, salad dressings, desserts, and meats. One of the major advantages of
these products is that they pass through the body without being absorbed. Further-
more, they are also claimed to eliminate some of the cholesterol already in the body.
The manufacture of a sucrose polyester obtained FDA approval and is sold under
the brand name Olestra. The metabolic role and possible future applications of
sucrose polyesters have been reviewed by Toma and co-workers. 147
The ultimate application of sucrose polyesters as food emulsifiers will depend
on the HLB value, which is determined by the specific fatty acid used. For example,
one such product made from stearic acid is used as an emulsifier in shortening or
margarine and could have an HLB value of 2 to 3, whereas another product made
from a different proportion of stearic acid and used as an emulsifier in ice cream or
in other dairy products could have an HLB value of 11.
In bakery foods, SEs are used in many ways. In 1969, Pomeranz et al. 148,149
reported on the addition of wheat glycolipids and SE to wheat flour that allowed