Effect of Fermentation on Nutrient and Anti-nutrient Composition of Millet （Pennisetum glaucum） and Soyabean （Glycine max） Blend Flours

This research was carried out to study the effect of fermentation on the chemical composition, anti-nutrient content, PH, titratable acidity, and microbiological changes of millet and soyabean blend. Millet and soyabean composite flours were mixed in gram of six combinations as follows millet and soyabean （A） = 100：0, millet and soyabean （B） = 90：10, millet and soyabean （C） = 80：20, millet and soyabean （D） = 70：30, millet and soyabean （E） = 60：40, millet and soyabean （F） = 50：50 and subjected to natural fermentation for 72 h. The following bacteria isolates were obtained from the fermentation; Lacobacillus fermentum, L. acidophilus, L. bulgaricus, L. plantarum, L. dextranicum, L. rhamnosus, L. delbrueckii, L. leichemanii, L. divergens, L. reuteri, L. jenseni, L. casei, L. salivarius, L. cellubiosus, Leuconostoc mesenteroide and Pediococcus acidilactis, of which L. plantarum was the most dominant the throughout the period of fermentation. There was decrease in pH with increase in TTA in all the samples. The result of the proximate analysis revealed a marginal increase in crude protein content of each sample （from 44.41 to 63.14, from 11.02 to 24.02, from 16.64 to 23.10, from 20.83 to 26.93, from 25.43 to 30.12, 39.12 to 35.86 and from 40.66 to 54.24%） There was increase in ash content and decrease in carbohydrate, fibre and fat contents of the fermented samples. Results from this research also show significant reduction in anti-nutritional content which are hydrogen cyanide, oxalate and phytate. Fermentation has modified the microbial and nutritional quality of the millet and soyabean blend and this has greatly improved the nutrient content of the blend.

Characteristics of microbial communities in fermentation of pickled ginger and their correlation with its volatile flavors

The effects of natural fermentation and inoculation fermentation on the volatile flavor substances of pickled ginger was studied.High-throughput sequencing and gas chromatographic-mass spectrometry were used to measure the bacterial community changes and its flavour compounds during one to six days’fermentation.First,55 and 51 volatile compounds were detected in the natural and the Lactiplantibacillus plantarum-inoculated fermentation samples,respectively.Alkenes,alcohols,aldehydes and esters were the main volatile components of both types of fermented ginger,but their contents were different.Then,40 and 43 bacterial genera were detected in the natural and inoculation fermented gingers,respectively,including 15 major bacterial genera such as Lactobacillus.However,the abundance of bacterial genera in the samples was different.The correlation analysis showed that a total of 43 bacterial genera had medium to high correlations with 49 volatile flavor compounds(|ρ|>0.6),including one aldehyde,two ketones,five esters,nine alcohols and 32 olefins.The comprehensive results showed that,compared with natural fermentation,inoculation fermentation could change the abundance of bacteria in pickled ginger,thereby improving the volatile flavor compounds of this popular product.