Effect of Processing and Fermentation on Functional Properties and on Anti-nutritional Factors in Horse Gram (Macrotyloma uniflorum)

Aim: The study was conducted to understand the Effect of processing and fermentation on functional properties and on anti-nutritional factors in Horse Gram (Macrotyloma uniflorum).

Place and Duration of Work: The study was carried out in Department of Agricultural Microbiology, GKVK, University of Agricultural Sciences, Bangalore during 2019-20.

Methodology: Horse gram seeds were procured from National seed project, thoroughly cleaned and were subjected to different processing methods (soaking, roasting, cooking and germination) and ground into flour. Then, the processed flours were analyzed for altered functional properties like bulk density, water and oil absorption capacity, foaming capacity and stability etc. The raw seeds were directly milled into flour without any processing and used as control. Further, all processed flours were subjected to fermentation and compared with non fermented flours for reduction of antinutritional factors (tannins and phytates).

Results: The functional properties of unprocessed (raw) horse gram flour was recorded with values of 0.95 g / g (Bulk density), 1.87 g / mL(water absorption capacity),1.45 g / mL(oil absorption capacity), 7.56% (foaming capacity) and 70.78% for foaming stability. Whereas, the processing significantly altered the functional properties. When it comes to antinutritional factors, unprocessed flour recorded with 7.9 mg / g of tannins and 0.96 mg / g of phytates. The processing in combination with fermentation facilitate further reduction of antinutrients compared to processing alone (without fermentation). Among them, fermented germinated flour and fermented cooked flour proven their efficiency in reduction of tannins (61.3 and 62.5%) and phytates (54.1 and 46.8%) compared to other processed flours.

Conclusion: Based on results, it is evidenced that processing altered functional properties of horse gram effectively. However, processing combined with fermentation yielded higher reduction in antinutritional factors compared to processing alone. Further, germinated flour and cooked flour on fermentation were found to yield significantly higher reduction in antinutritional factors thereby enhancing its utilization in functional foods as main / partial ingredient.