Amylolytic process or amylolysis is the conversion of
starch into
sugar by the action of
acids
In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a ...
or
enzymes such as
amylase
An amylase () is an enzyme that catalyses the hydrolysis of starch (Latin ') into sugars. Amylase is present in the saliva of humans and some other mammals, where it begins the chemical process of digestion. Foods that contain large amounts of ...
.
Starch begins to pile up inside the leaves of plants during times of light when starch is able to be produced by photosynthetic processes. This ability to make starch disappears in the dark due to the lack of illumination; there is insufficient amount of light produced during the dark needed to carry this reaction forward. Turning starch into sugar is done by the enzyme amylase.
Different pathways of amylase & location of amylase activity
The process in which amylase breaks down starch for sugar consumption is not consistent with all organisms that use amylase to breakdown stored starch. There are different amylase pathways that are involved in starch degradation. The occurrence of starch degradation into sugar by the enzyme amylase was most commonly known to take place in the
Chloroplast, but that has been proven wrong. One example is the spinach plant, in which the chloroplast contains both
alpha and
beta amylase
β-Amylase (EC 3.2.1.2 , saccharogen amylase, glycogenase) is an enzyme with the systematic name ''4-α-D-glucan maltohydrolase''. It catalyses the following reaction:
: Hydrolysis of (1→4)-α-D-glucosidic linkages in polysaccharides so as to ...
(They are different versions of amylase involved in the breakdown of starch and they differ in their substrate specificity). In spinach leaves, the extrachloroplastic region contains the highest level of amylase degradation of starch. The difference between chloroplast and extrachloroplastic starch degradation is in the amylase pathway they prefer; either beta or alpha amylase. For spinach leaves,
Alpha-amylase
α-Amylase is an enzyme (EC 3.2.1.1; systematic name 4-α-D-glucan glucanohydrolase) that hydrolyses α bonds of large, α-linked polysaccharides, such as starch and glycogen, yielding shorter chains thereof, dextrins, and maltose:
:Endohyd ...
is preferred but for plants/organisms like wheat, barley, peas, etc. the
Beta-amylase
β-Amylase (EC 3.2.1.2 , saccharogen amylase, glycogenase) is an enzyme with the systematic name ''4-α-D-glucan maltohydrolase''. It catalyses the following reaction:
: Hydrolysis of (1→4)-α-D-glucosidic linkages in polysaccharides so as to ...
is preferred.
Usage
The amylolytic process is used in the brewing of alcohol from grains. Since grains contain starches but little to no simple sugars, the sugar needed to produce alcohol is derived from starch via the amylolytic process. In
beer brewing, this is done through
malting. In
sake
Sake, also spelled saké ( ; also referred to as Japanese rice wine), is an alcoholic beverage of Japanese origin made by fermenting rice that has been polished to remove the bran. Despite the name ''Japanese rice wine'', sake, and indee ...
brewing, the mold
Aspergillus oryzae provides amylolysis, and in
Tapai
''Tapai'' (also ''tapay'' or ''tape'') is a traditional fermented preparation of rice or other starchy foods, and is found throughout much of Southeast Asia, especially in Austronesian cultures, and parts of East Asia. It refers to both the ...
,
Saccharomyces cerevisiae
''Saccharomyces cerevisiae'' () (brewer's yeast or baker's yeast) is a species of yeast (single-celled fungus microorganisms). The species has been instrumental in winemaking, baking, and brewing since ancient times. It is believed to have b ...
. The amylolytic process can also be used to allow for maximum results in production. For instance, glucose formation, when amylolytic enzymes are added to a given compound, the enzymes work to give maximum formation. The amylolytic process is also useful in the breaking down of molecules, it can be closely associated with the process of hydrolysis.
See also
*
Brewing methods
References
Carbohydrate chemistry
Biochemistry
Cooking techniques
Rice wine
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