Enzyme heating

Enzyme—Heat—Enzyme Process. The enzyme—heat—enzyme (EHE) process was the first industrial enzymatic Hquefaction procedure developed and utilizes a B. subtilis, also referred to as B. amjloliquefaciens, a-amylase for hydrolysis. The enzyme can be used at temperatures up to about 90°C before a significant loss in activity occurs. After an initial hydrolysis step a high temperature heat treatment step is needed to solubilize residual starch present as a fatty acid/amylose complex. The heat treatment inactivates the a-amylase, thus a second addition of enzyme is required to complete the reaction. 

Although chlorophyll and chlorophyllin colorants seem to be easily obtained, in practice their production as natural food colorants is rather difficult. The sensitivity of chlorophylls to certain enzymes, heat, and low pH, and their low tinctorial strength greatly limit their manufacture and application as food additives, principally when the pigments are isolated from the protective environment of the chloroplasts. The well-known instability of chlorophylls prompted extensive research for developing... 

Food flavor is governed by many factors, including lipid oxidation and protein degradation. Enzyme-catalyzed oxidation ( ) and autoxidation (2) can substantially alter the flavor q ality of foods. In "addition, protein degradation, whether caused by enzymes, heat, or interactions with other compounds, can also affect flavor characteristics of certain foods (3, 4, ... 

Prions are of particular significance in a pharmaceutical context because of the need to decontaminate surgical or other hospital equipment that has been in contact with diseased tissue. Prion proteins are very stable and resist proteolytic enzymes, heat,... 

Dissolution testing of indapamide is accomplished using the rotating basket method (USP Method I) with 900 mL of simulated gastric fluid T.S. without enzymes heated to 37<>C as the dissolution medium and a basket rotation of 100 rpm. Samples are placed in the baskets and the baskets are then lowered into the dissolution medium with samples withdrawn at appropriate intervals. The samples are filtered through 0.45 pm Miilipore filters. The dissolution medium is assayed for indapamide against appropriate standards using an UV absorbance assay (23). 

In addition to influencing the rate of lipid oxidation via activation of thiol groups and metallo-enzymes, heating milk may also affect oxidation via redistribution of Cu (which migrates to the FGM on heating) and possibly by the formation of Maillard browning products, some of which have metal chelating and antioxidant properties. 

Quantity of pyocyaneua protease. Enzyme Enzyme heated 30 m. at Enzyme brought to lOo. ... 

Thermostable enzymes, heat stable enzymes a small number of enzymes, mostly hydrolases, which show their highest activity between 60 and 80 °C, and which are stable and catalytically active at up to -100 °C. T.e. usually have a compact structure, stabilized by many disulfide bonds and/or extensive hydro-phobic regions, and a low a-helix content. Examples... 

In the food industry the inter-relationship between micro-organism growth, temperature and time is of vital importance. For the destruction of micro-organisms and the inactivation of enzymes, heat treatment may well be selected. Other possibilities include chemicals and ionising radiation. 

Active immobilized enzyme heat-transfer study of packed reactors incorporating immobilized glucoamylase Active immobilized enzyme... 

The folding and coiling pattei-ns of a protein often affect its biological activity, for instance, its effectiveness as an enzyme. Heat and the ionic environment can alter the pattern of folding and coiling, causing the enzyme or protein to become inactive, or denatured. 

Co-enzymes.—Heat-stable organic compomids naturally associated with complex enzyme systems, and necessary for zymolysis. They act as carriers of hydrogen, phosphate, or other intermediate reactants in the system. 

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