Abstract:

In order to propel the value-added utilization of peanut hull as a byproduct of peanut processing, the optimal extraction technology of water insoluble dietary fiber (IDF) from the material based on sequential treatment with alkaline followed by acid was investigated using single factor method combined with orthogonal array design. Results showed that the optimal technological process for extracting IDF from powdered peanut hull with particle size below 50 mesh were based on 30 min hot water bath (40 ℃) treatment of a mixture consisting of 60 mL of 4% aqueous NaOH solution and 3 g of raw material followed by 90 min hot water bath (60 ℃) treatment of a mixture composed of 60 mL of 0.01 mol/L HCl and the residue left after alkaline treatment. The target product with an extraction yield of 86.44%, purity of 91.13% and their weighed score (weight ratio 2:1) of 88.01 was obtained using this optimal process.

Key words: peanut hull, water insoluble dietary fiber, extraction