Biomedical Engineering Reference
In-Depth Information
Monoglyceride Citrates
Monoglyceride Lactates
Monoglyceride Acetate (GMA)
Propylene Glycol Esters
Stearoyl Lactylates (SL)
Sorbitan Esters and Erthoxylated Sorbitan Esters
Polyglycerol Esters
Sucrose Esters (SE)
Naturally Occurring Emulsifiers
Proteins
Chemically and Enzymatically Modified Proteins
Hydrocolloids
Gum Arabic
“Emulsan”— A Microbial Hydropcolloid
Non-Proteineous Gums
References
INTRODUCTION
Lecithins, gum arabic, caseins, soy proteins, monoglycerides, and other naturally
occurring molecules have been used for many years in foods because of their surface
activity. Terminology such as “additives that retard precipitation of dispersed parti-
cles”,“decrease creaming rates of oil droplets or foams”,“prevent aggrega-
tion/desegregation of dispersed solid or liquid particles”,“prevent syneresis of gelled
systems”,“condition or stabilize food systems”, and “retard coalescence of oil
droplets” is often used by food technologists to describe the role of such additives.
In general, these molecules are known as emulsifiers and/or stabilizers. The use of
such molecules in the food industry was based primarily on practical experience of
trial-and-error. Only during the last 25 years has more scientific work been carried
out to understand better the structural association and surface activity of these
molecules.
Food emulsions, foams, and dispersions are very complex systems containing
air, oil, and water as well as other phases such as gas cells, fat crystals, protein,
dissolved salts or carbohydrates, fibers, water-soluble polysaccharides, starch gran-
ules, or gels, etc. Simple man-made food emulsions, like margarine, mayonnaise,
or salad dressing, in addition to the water-oil-emulsifier, often consist of several
ingredients such as minerals, spices, dyes, vitamins, etc., which complicate the
system. Most foods are considerably more complex. 1 The continuous phase can be
partially or completely solid, or tend to solidify with decrease in temperature (dairy
products). The semi-solid or solid phase can be crystalline (ice cream) or gelatinous
(desserts) and can consist of secondary dispersions of gas cells (whipped cream),
additional colloidal solids, or macroscopic solid particles (meat emulsions). The
dispersed phase can in itself be liquid (vegetable oil), semi-solid, solid or a combi-
nation of the two ( Table 7.1 ). The stabilizers/emulsifiers can be complex blends of
proteins (solid or soluble), hydrocolloids, and small molecules. 2 In addition, the
 
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