Dehydration of Freshly Starter Assisted and Naturally Fermented Seeds of G.max Using Different Dehydrating Methods and its Physicochemical Effects

Abstract

Four kilograms of soya bean seeds (Glycine max) were purchased from Kawo market, Kaduna, Kaduna state of Nigeria. These seeds were transported to the laboratory, Department of Microbiology, Ahmadu Bello University Zaria. G.max seeds were precleaned and processed for fermentation. Processed unfermented seeds of G.max (300g) were transferred into three earth pots lined with aluminum foil. 5% mixed Bacillus species (B.subtilis and B.pumilus) both standard and test strains were prepared as starter cultures and were calibrated using McFarland standard 7. Pot A was inoculated with standard strains of B.subtilis and B.pumilus (starter A) while pot B was inoculated with test strains of B.subtilis and B.pumilus (starter B), pot C was allowed to ferment naturally. Fermentation in all the earth pots was allowed to progress at room temperature (28±2⁰C). It was observed that fermentation in earth pots with starters A and B fermented faster (48hrs) as compared to natural fermentation (pot C), (72hrs). Freshly fermented seeds were subjected to different drying conditions (solar drying, hot air oven drying, vacuum drying, direct sunlight drying protected with a net and direct sunlight drying without net). Fermented dried seeds of G.max were converted into powdered form using a sterile blender. Physicochemical analyses were carried out on powdered form under different conditions of drying. It was observed that G.max powdered condiment subjected to vacuum drying gave lowest values of moisture content, titratable acidity, peroxide values as oppose to higher values in other drying conditions. G.max powdered condiment dried using vacuum dryer can be preserved for use over a longer period of time.

Keywords: G.max, fermentation, starter assisted, B.pumilus, B.subtilis, earth pots, aluminum foil, solar dryer, vacuum dryer, hot air oven