Enzymatic maceration

Enzymatic maceration, which is a softening of plant tissue by the use of enzymes, has some potential quality advantages over mechanical-thermal disintegration as maceration is obtained with less damage to the cell walls. The major part of the plant cells remains intact by enzymatic maceration [25], as the enzymes attack only the space between the cells, and with only rare injury to the cell membrane [26]. The intact cells protect nutritional components within the cells which minimise flavour changes and deterioration on storage [27,28]. 

Enzymatic maceration of apple parenchyma modelling of the degradation... 

Sakho M, Chassagne D, Jaus A, Chiarazzo E and Crouzet J. 1997. Enzymatic maceration effects on volatile components of mango pulp. J Food Sci 63(6) 975-978. 

Cloud stability in citrus juices Pectin manufacture from citrus pomace Distillates from fermented fruit pulps Enzymatic maceration of fruits and vegetables Self-clarification of lemon/lime and apple juices Pressing characteristics of citrus pomace Ca2 -firming of fruits and vegetables... 

Process Va.ria.tlons. The conventional techniques for tea manufacture have been replaced in part by newer processing methods adopted for a greater degree of automation and control. These newer methods include withering modification (78), different types of maceration equipment (79), closed systems for fermentation (80), and fluid-bed dryers (81). A thermal process has been described which utilizes decreased time periods for enzymatic reactions but depends on heat treatment at 50—65°C to develop black tea character (82). It is claimed that tannin—protein complex formation is decreased and, therefore, greater tannin extractabiUty is achieved. Tea value is beheved to be increased through use of this process. 

They also suggested the lipids were released and became extractable primarily through enzymatic reactions after maceration of the leaves for extraction. Thus, they postulated that the time interval between maceration of the plant tissue and the application of heat to coagulate proteins was critical. They recommended heat inactivation of enzymes and precipitation of proteins as quickly as possible after maceration to minimize this interference. 

A highly reactive natural product which contains such a geminally donor-acceptor substituted alkene is protoanemonin (Scheme 3.12), a toxic, skin-irritating lactone produced by various plants (ranunculaceae). The natural precursor to this compound is the glucoside ranunculin [44, 45], which yields protoanemonin enzymatically on maceration of plant tissue. Protoanemonin is unstable and quickly polymerizes or dimerizes to the less toxic anemonin. 

Harvest the cellulase-containing transgenic plants while they are green, macerate them, and separate the solid to produce an enzyme concentrate, which can later be used in the enzymatic hydrolysis of pretreated biomass. Depending on the production level of this enzyme in transgenic plants, the need for externally added cellu-lases in the enzymatic hydrolysis step might be avoided or minimized. 

Together with fermentation, both the prefermentative and simultaneous maceration influences the supply of essential yeast nutrients and substrates for their enzymatic transformation. The release of nutrients from the pomace is also under the influence of heat and alcohol, generated by yeast metabolism. 

Poussier, M., GuiUoux-Benatier, M., Torres, M., Heras, E., Adrian, M. (2003). Influence of different maceration techniques and microbial enzymatic activities on wine stilbene content. Am. J. Enol. Vitic., 54, 261-266. 

Ochratoxin A is mainly associated with grapes and derived products. Red grape juice contains higher levels of the toxin, because a prolonged maceration and an enzymatic treatment are applied to increase color yield. Because ochratoxin A is stable in ethanol, wine also is frequently contaminated with ochratoxin A, although fining reduces ochratoxin A levels to a certain degree. 

The methods for isolation of steroid saponins are similar to those of triterpenoid saponins. Since glycosides, as a class, are particularly prone to enzymatic or microbial degradation, processing of plant material needs to be started soon after collection to avoid delays. Air-dried powdered plant material is defatted and then extracted, either with cold or hot methanol or ethanol or with 50% aqueous ethanol or methanol at ambient temperature. Usually the extract is concentrated at reduced pressure, macerated with water, and partitioned successively using ethyl acetate and re-BuOH. Most of the saponin constituents are found in the n-BuOH soluble fraction. However, highly polar glycosides may be found in the aqueous layer. 

Begin maceration and clearing by transferring to an enzymatic solution of 1% trypsin in 30% saturated sodium borate. Check every day, changing the solution each time. 

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