Phytic acid fermentation

Various processing techniques, other than fermentation, can be utilized to remove phytic acid and other dietary fiber materials that reduce mineral absorption (109). Processes would include differential extraction and filtration techniques such as ultrafiltration (125, 126, 127). 

Phytase (Aspergillus niger var.) Produced as an off white to brown powder or as a tan to dark brown liquid by controlled fermentation using Aspergillus niger var. Soluble in water, but practically insoluble in alcohol, in chloroform, and in ether. Major active principles (1) 3-phytase and (2) acid phosphatase. Typical applications used in the production of soy protein isolate and in the removal of phytic acid from plant materials. 

By increasing the fermentation period when making the dough for the bread, the decreased zinc absorption in whole flour bread can be overcome. The phytic acid is in this way broken down, and the zinc better available absorption. 

Tamarind seeds also contain small amounts of anti-nutritional factors such as tannins, phytic acid, hydrogen cyanide, trypsin inhibitor activity and phytohaemaglutination activity, (5). The presence of tannins and other coloring matter in the testa make the whole seeds unsuitable for direct human consumption. Therefore, the testa has to be separated from the kernels by boiling or roasting. Otherwise, side effects such as depression, constipation and gastrointestinal disorders may result (Anon, 1976, cited in (5)). Bhatta et al. (2001, cited in (5)), have considered that a natural source of tannin from tamarind seed husks can be used to depress gas production in mmen fermentation, particularly in crossbred dairy cows. 

In his Natural History (1826), Pliny the Elder stated that those persons who are dieted npon fermented bread are stronger in body , which is an early statement on the health benefits of sourdough breads. Whole meals of cereals are a good source of minerals. Their bioavailability is limited, as they are often bound to phytic acid (myo-inositol-hexophospate). Wheat and rye contain about 1.2% of dry matter (Fretzdorff Briimmer, 1992). With the drop in pH during sourdough fermentation, endogenous phytases of the cereals are activated and the bound minerals are released (Fretzdorff Briimmer, 1992). Lactic acid bacteria and yeasts also possess phytase... 

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