Effect of natural fermentation on the content of inositol phosphates in lentils

The effects of natural fermentation upon phytic acid and less phosphorylated inositol phosphates of Lens culinaris var vulgaris cultivar Magda-20 were investigated. Seven fermentation runs were made following a 2(2) complete factorial design with three replicated centre points to study the effect of different conditions of temperature (28, 35 and 42 degrees C) and broth concentration (79, 150 and 221 g/l). Samples were taken for each of them at daily intervals (0, 24, 48, 72 and 96 h). The pH value declined sharply in the first 24 h of fermentation, becoming stabilized from this time. The relation between lactic acid and titratable acidity presented important differences between the different fermentations, ranging from 30-80%. Phytic acid (IP6), inositol pentakis (IP5), tetrakis (IP4) and tris-(IP3) phosphates were quantitatively determined. The content of total inositol phosphates showed a maximum reduction of 63% at 72 h under the fermentation conditions of 42 degrees C and 79 g/l.