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TREHALOSE
Trehalose, also known as mycose, is a 1-alpha (disaccharide) sugar found extensively but not abundantly in nature. It is thought to be implicated in anhydrobiosis - the ability of plants and animals to withstand prolonged periods of desiccation. The sugar is thought to form a gel phase as cells dehydrate, which prevents disruption of internal cell organelles by effectively splinting them in position. Rehydration then allows normal cellular activity to be resumed without the major, generally lethal damage that would normally follow a dehydration/reyhdration cycle.
Chemistry
Trehalose is a non-reducing sugar formed from two glucose units joined by a 1-1 alpha bond giving it the name of α-D-glucopyranoglucopyranosyl-1,1-α-D-glucopyranoside. The bonding makes trehalose very resistant to acid hydrolysis, and therefore stable in solution at high temperatures even under acidic conditions. The bonding also keeps non-reducing sugars in closed-ring form, such that the aldehyde or ketone end-groups do not bind to the lysine or arginine residues of proteins (a process called glycation). The enzyme trehalase, present but not abundant in most people, breaks it into two glucose molecules, which can then be readily absorbed in the gut.
Trehalose has about 45% the sweetness of sucrose. Trehalose is less soluble than sucrose, except at high temperatures (>80°C). Trehalose forms a rhomboid crystal as the dihydrate, and has 90% of the calorific content of sucrose in that form. Anhydrous forms of Trehalose readily regain moisture to form the dihydrate.
Trehalose is metabolized by a number of bacteria, including Streptococcus mutans, the common oral bacteria responsible for oral plaque.
Anhydrous forms of trehalose can show interesting physical properties when heat treated.
Natural sources
Use
Trehalose has been accepted as a novel food ingredient under the GRAS terms in the US and the EU. Trehalose has also found commercial application as a food ingredient. However, less-soluble and less-sweet than sucrose, trehalose is seldom used as a direct replacement for conventional sweeteners, such as sucrose, regarded as the "gold standard." The development has come out of Japan, where enzyme-based processes have been developed to convert wheat and corn syrups.
See also
it is an important components of insects circulating fluid.It acts as a storage form of insect circulating fluid and it is important in respiration.
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