In the master thesis we investigated the influence of spontaneous fermentation and fermentation with addition of commercially available starter culture on the formation of biogenic amines (BA) and γ-aminobutyric acid (GABA), the content of soluble antioxidants and free amino groups in three chickpea flours from different manufacturers. We also determined the influence of fermentation time (24 and 48 hours) and differences between the flours of different origin. In both fermentation methods there was a time dependent increase in the content of BA and GABA, soluble antioxidants and free amino groups. The spontaneous fermentation of each of the three flours resulted in a different BA profile. In the individual flours, a strong increase of nutritionally undesirable BA tyramine (TYR), cadaverine (KAD) and putrescine was observed. The addition of commercial starter cultures generally resulted in lower KAD and TYR lower content, but due to the large differences in BA content between the flours, the effect of the autochthonous microflora could not be eliminated. From the sour dough (SD) of chickpea flour and type 400 wheat flour we baked bread and evaluated the conversion of BA and GABA. Baking resulted in a reduced BA content in the crust and no decrease in the crumb. The content of GABA (48.3 mg /100g) in the bread was high, which is desirable from a nutritional point of view. We isolated lactic acid bacteria of the autochthonous microflora of SD and used them as starter cultures, with which we reduced the accumulation of BA in SD effectively. We also reduced the BA content in SD and in bread dough by Fenugreek sprouts, in which diamine oxidase is expressed.
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