Plasticity of Fats

The plasticity of fat is its ability to hold its shape but still be molded or shaped under light pressure. Plasticity determines a fat’s spreadability. It is an important characteristic to consider when choosing which fat to use in the preparation of confections, icings, pastries, and other baked products. Although most fats look solid at room temperature, they are actually composed of liquid oil with a network of solid fat crystals holding it in place. Read more »

The Melting Point of Fats

Fatty acids are single molecules, each with a distinct melting point. Because triglycerides contain different fatty acids, food fats have a range of melting temperatures. Ultimately, four factors determine a fat’s melting point:

• The fatty acid’s degree of saturation
• The length of its carbon chain
• Its cis-trans configuration
• Its crystalline structure

Read more »

Types of Emulsions

Emulsions can be temporary, semipermanent, or permanent and differ in their degree of viscosity and stability. Stability is defined by the degree to which the liquids stay in emulsion regardless of gravity, agitation, long storage times, extreme temperatures, surface drying, or added salt. Read more »

Emulsifiers

There are three parts to an emulsion:

• The dispersed or discontinuous phase, usually oil
• The dispersion or continuous phase, most like water-based
• An emulsifier, which is a stabilizing compound that helps keep one phase dispersed in the other

Read more »

Emulsions

Fats play an important role in the formation of emulsions. All foods containing some liquid, and if fats or oils are present, then the combination is some type of emulsion. Emulsions are continuous blends described as either oil-in-water, in which oil droplets are dispersed throughout the water, or water-in-oil, in which water droplets are dispersed throughout the oil. Read more »

The shortening power of certain fats make them essential in the preparation of pastries, pie crusts, biscuits, and cakes. The more highly saturated fats tend to have greater shortening power. Incorporated into a flour mixture, fat separates the flour’s starch and protein and, when heated, melts into the dough, leavening the air spaces that give the finished product its characteristic delicate texture. A fine grain is created from certain cake and cookie batters with the use of shortenings that gently encase the numerous air bubbles, serving as a starting point for the air to expand and increase overall volume. Baked goods also become more tender, up to a point, as fat concentration increases.

Functions of Fats in Food

It is difficult to substitute any other ingredient for the functional characteristics of fats. The unique configuration of the triglyceride molecule, specifically the length and saturation of the three fatty acids, contributes to its ability to be used as a heat transfer medium and a shortening and to play an important role in emulsions. It also influences a fat’s melting point, plasticity, solubility, flavor, and nutrient content. Read more »

Cooking with Fats and Oils

Fats and oils have yet to be matched by another food component when it comes to imparting their unique properties to foods. Flavor, consisting of taste, aroma, and mouthfeel, which is developed in certain foods by their fat or oil content, is very difficult to duplicate. Read more »

Around the world, the search continues for a sweetening substance without the calorie (kcal) content of sugar. Several sweeteners from a variety of sources are being investigated or are awaiting approval. The chemical structure of alternative sweeteners varies tremendously and includes peptides, amino acids, carbohydrates, inorganic salts, and synthetic compounds. Read more »

Acesulfame-K as an Artificial Sweetener

Acesulface-K was discovered in 1967 and, like the other artificial sweeteners, was stumbled upon by accident. Sold as Sunette, Acesulfame-K was FDA-approved in 1988 for use in tabletop sweeteners, dry beverage mixes, and chewing gum. It is 130 times sweeter than sucrose and is stable to heating and cooling, but it has a bitter aftertaste like that of saccharin. Read more »