- published: 18 Sep 2014
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Classical may refer to:
Fruit preserves are preparations of fruits, vegetables and sugar, often canned or sealed for long-term storage.
Many varieties of fruit preserves are made globally, including sweet fruit preserves, such as strawberry or apricot, as well as savoury preserves of vegetables, such as tomatoes or squash. The ingredients used and how they are prepared determine the type of preserves; jams, jellies, and marmalades are all examples of different styles of fruit preserves that vary based upon the fruit used. In English the world over the plural form "preserves" is used to describe all types of jams and jellies.
The term 'preserves' is usually interchangeable with 'jams'. Some cookbooks define preserves as cooked and gelled whole fruit (or vegetable), which includes a significant portion of the fruit. In the English speaking world, the two terms are more strictly differentiated and, when this is not the case, the more usual generic term is 'jam'.
Jam apart from being a particular type of preserve (spreadable containing the fruit) is also used as a general term (in British and Commonwealth English) for any type of fruit preserve (e.g. "the jam factory in Tiptree") while in the US the term jelly is preferred; e.g. a jam donut or a jam sandwich in the UK, Ireland and Canada is a jelly donut and a jelly sandwich in the US.
In chemistry, soap is a salt of a fatty acid. Consumers mainly use soaps as surfactants for washing, bathing, and cleaning, but they are also used in textile spinning and are important components of lubricants.
Soaps for cleansing are obtained by treating vegetable or animal oils and fats with a strongly alkaline solution. Fats and oils are composed of triglycerides; three molecules of fatty acids attach to a single molecule of glycerol. The alkaline solution, which is often called lye (although the term "lye soap" refers almost exclusively to soaps made with sodium hydroxide), brings about a chemical reaction known as saponification.
In this reaction, the triglyceride fats first hydrolyze into free fatty acids, and then these combine with the alkali to form crude soap: an amalgam of various soap salts, excess fat or alkali, water, and liberated glycerol (glycerin). The glycerin, a useful by-product, can remain in the soap product as a softening agent, or be isolated for other uses.
Soaps are key components of most lubricating greases, which are usually emulsions of calcium soap or lithium soap and mineral oil. These calcium- and lithium-based greases are widely used. Many other metallic soaps are also useful, including those of aluminium, sodium, and mixtures of them. Such soaps are also used as thickeners to increase the viscosity of oils. In ancient times, lubricating greases were made by the addition of lime to olive oil.