AQA video: Sauce making and methods of heat transfer. BNF factsheet: Food functions: Thicken. BNF factsheet: Food functions: Set. Experiment sheet: Testing for starch. Starch gels freeze-thaw stability and gel strength experiment.
Skip to main content. Carbohydrates: gelatinisation. Starch gelatinization is the process where starch and water are subjected to heat, causing the starch granules to swell. As a result, the water is gradually absorbed in an irreversible manner.
This gives the system a viscous and transparent texture. The result of the reaction is a gel, which is used in sauces, puddings, creams, and other food products, providing a pleasing texture.
Starch-based gels are thermo-irreversible, meaning that they do not melt upon heating unlike gelatin, which we will discuss later. The most common examples of starch gelatinization are found in sauce and pasta preparations and baked goods. Starch molecules make up the majority of most baked goods, so starch is an important part of the structure. Starches develop a softer structure when baked than proteins do.
The softness of the crumb of baked bread is due largely to the starch. The more protein structure there is, the chewier the bread. Starches can be fairly straightforward extracts of plants, such as cornstarch , tapioca , or arrowroot , but there are also modified starches and pre-gelatinized starches available that have specific uses.
See Table 1 for a list of different thickening and binding agents and their characteristics. Thickened mixture simmered until no starch taste remains Used to thicken sauces when a clear glossy texture is desired, such as dessert sauces and in Asian-inspired dishes. Sensitive to extended heat exposure, so products become thin if held at heat for long periods of time.
Quite stable at extreme temperatures heat and freezing Modified starches Dissolved in cold water. Modified starches are often used in commercially processed foods and convenience products. Modified to improve specific characteristics e. Gelatin g gelatin sets 1 L liquid Powder or sheets leaves dissolved in cold water. Activates with heat, sets when cold Derived from collagens in bones and meats of animals.
Agar agar g agar agar sets 1 L liquid Powder dissolved in cold water. Gelling agents Gelatin is a water-soluble protein extracted from animal tissue and used as a gelling agent, a thickener, an emulsifier, a whipping agent, a stabilizer, and a substance that imparts a smooth mouth feel to foods. Gels can range from very soft to very hard. New modern aero-gels have fascinating properties.
Gelatin is a protein formed when collagen a connective protein in animals is heated under moist conditions. Gelatin forms cross-linked networks exceedingly well, and therefore is a wonderful gelling agent. The name has also taken to mean the gel created from gelatin and a water-based liquid like stock or sugary flavored water.
You may have guessed by now that gels in general take their name from gelatin. So the specific answer to the first part of your question is: gels are the general category, and gelatin in the second sense is a specific kind of gel. I have never heard the term gellification. The only verb I am familiar with is to gel.
The process is gelatinization or more familiar to me , just gelling. In those links in Wikipedia for gel , gelatin , collagen , and areogel you will find out much more. Gelatinization means the starch grains swelling, releasing the starch molecules, which then cross link to thicken the liquid. The gel forms, trapping water between chains of starch. It is a heating process. Gelation is a cooling process as the gel sets. Sign up to join this community.
The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Differences between gel and gelatine Ask Question. Asked 8 years, 11 months ago.
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