Zeitschrift für Lebensmittelverarbeitung und -technologie

Abstrakt

Recovery of Antioxidants from Grape Seeds and its Application in Fried Food

Benjaruk Vayupharp and Varaporn Laksanalamai

The efficiency of organic solvents and the conditions for extraction of phenolics from grape seeds was investigated. Two selected organic solvents; aqueous ethanol and acetone were studied at various concentrations between 0 - 100% and the extraction was performed either at room temperature or at 50°C for 3 - 12 hours. Results indicated that at 50ºC for 6 hours the best extraction yield of 14.9% was obtained with 50% (v / v) ethanol. Under this condition, the extract consisted of 0.33 (g / g grape seed) total phenol. The EC50 measured by the 2,2-diphenyl- 1-picrylhydrazyl (DPPH) method and reducing power were 214.6 μg/ml and 2.38 respectively, which implied a high antioxidant activity of the extract. When considering the cost of operation and the safety concerns associated with solvent residue in the product, aqueous ethanol (50%, v / v) was an appropriate solvent comparing to aqueous acetone at various concentrations. Also, the effect of the extract on retarding oxidative rancidity of fried pork products was compared with 2 commercial additives; butylated hydroxytoluene (BHT) and gallic acid. At the concentration of 1.6 (g / kg product) the extract was similar in retarding rancidity efficiency to BHT but lower than gallic acid.