Strategic Nutrient Enhancement of Mustard Oil Seed Cake by Briquetting and Koji Fermentation for Ruminants Feed

Abstract

PurposeEdible oil industries are shifting to the increased production of cold pressed oils in order to preserve some of the vital nutrients the oil. Consequently, the seed cake residue would lack significant nutrients that are otherwise retained in the oils, thus making the quality of residue inferior when applying as cattle feed. MethodsIn this study, mustard oil seed cake (MOSC) was employed as the substrate and the nutritive and feed quality were enhanced using Koji strains viz., Aspergillus oryzae and Aspergillus niger, separately and suitable process parameters such as Solid: Liquid, pH, incubation time and inoculum quantity were optimized for the maximum nutritive enhancement of cold pressed MOSC. Changes in physico-chemical properties were analyzed by SEM, EDS, FTIR along with feed functional properties to analyze the quality. Briquetting of MOSC was employed for enhanced microbial encroachment.ResultFree amino acid (FAA) and reducing sugar (RS) were chosen as critical indicators of enrichment. A. oryzae resulted in 20.74 fold and 19.07 fold increase in FAA and RS respectively, whereas, A. niger resulted 13.24 fold and 3.04 fold increase. Critical parameters such as solid:liquid, pH, time and inoculum volume were selected. Briquetting resulted in efficient mycelia coverage as evident from SEM images and EDS analysis indicated enhancement in essential elements in the MOSC. Functional properties after fermentation indicated an effective transformation of MOSC. ConclusionUtilizing these seed cakes as cattle feed not only provide the required nutrition, but also helps in the efficient utilization of the residual waste oilseed cakes.