Abstract: Filamentous fungi have been widely used to produce hydrolytic enzymes for industrial applications. Amylase and glucoamylase were produced using Aspergillus oryzae under solid state fermentation. The enzymes obtained were partially purified using isopropanol and rice flour was treated with these hydrolysing enzymes. Enzymatic pretreatment conditions were optimized using Response Surface Methodology (RSM). Effect of different parameters such as slurry concentration, enzyme concentration, time and temperature was studied. Enriched rice flour was obtained by treating 7% slurry with 1 mL of enzyme at 55°C for 40 min. This enriched rice flour was analysed for its nutritional, functional, toxic residues and microbiological parameters. Protein content of the enzymatically treated rice flour increased from 8.03-20.79% (2.5 fold enhancement) and ash from 0.69-1.40%. Fat content of both, untreated and treated rice flours, differed insignificantly but crude fiber was hydrolysed from 2.50-0.42. Moisture content of the treated rice flour decreased from 12.40-11.85%. The digestibility coefficient of in vitro digestibility also increased from 644.63-1351.67 in treated rice flour. Microbiological count of treated rice flour decreased whereas contaminating organisms (coliforms and salmonella) and toxic residues (aflatoxins) were not detected.
Shruti Puri, Maninder Arora and Loveleen Kaur Sarao, 2014. Optimization of the Use of Fungal Enzymes Amylase and Glucoamylase to Enhance the Nutritional and Functional Properties of Rice Flour. Journal of Food Technology, 12: 33-47.