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low methoxyl pectins have a degree of esterification of less than 50, [35] [32] can be either amidated or non-amidated: the percentage level of substitution of the amide group, defined as the degree of amidation, defines the efficacy of a pectin; [32] low methoxyl pectins can provide a range of textures and rheological properties, depending on ...
Pectinesterase (EC 3.1.1.11; systematic name pectin pectylhydrolase) is a ubiquitous cell-wall-associated enzyme that presents several isoforms that facilitate plant cell wall modification and subsequent breakdown. It catalyzes the following reaction:
It is useful because pectin is the jelly-like matrix which helps cement plant cells together and in which other cell wall components, such as cellulose fibrils, are embedded. Therefore, pectinase enzymes are commonly used in processes involving the degradation of plant materials, such as speeding up the extraction of fruit juice from fruit ...
The natural esterification that takes place in wines and other alcoholic beverages during the aging process is an example of acid-catalysed esterification. Over time, the acidity of the acetic acid and tannins in an aging wine will catalytically protonate other organic acids (including acetic acid itself), encouraging ethanol to react as a ...
Fischer–Speier esterification - a more general reaction where an alcohol and carboxylic acid are coupled to form an ester Helferich method - a glycosidation carried out with phenol [ 5 ] References
The kinetics and rates of step-growth polymerization can be described using a polyesterification mechanism. The simple esterification is an acid-catalyzed process in which protonation of the acid is followed by interaction with the alcohol to produce an ester and water. However, there are a few assumptions needed with this kinetic model.
The pectin lyase is playing a crucial role in many biotechnological uses including the textile industry, paper manufacturing, wastewater pretreatment of pectin, clarifying of the juice, and extraction of oil. It has the ability to efficiently break the pectin molecule's back bone by β-eliminating in order to form pectin-oligosaccharide.
In the food industry and biochemistry, interesterification (IE) is a process that rearranges the fatty acids of a fat product, typically a mixture of triglycerides.The process implies breaking and reforming the ester bonds C–O–C that connect the fatty acid chains to the glycerol hubs of the fat molecules.