Phenolics from Hazelnut Kernels by Supercritical Methanol Extraction

Abstract

Phenolics were obtained from hazelnut kernels by supercritical methanol extraction (SME). The SME was carried out at 515–535 K and under 10–30 MPa pressure. In a typical run, the autoclave was charged with a given amount of hazelnut kernels (5–10 g) and liquid methanol (20–40 g). The yield of extract increases with increasing both temperature and pressure in the SME process. The yield of extract increases from 63.3 to 78% under 35 MPa with increasing of temperature from 515 to 535 K, respectively, and it increases from 58.0 to 78.0% with increasing of pressure from 10 to 30 MPa, respectively. The phenolic compounds were isolated from the SME extracts by means of chemical methods. The highest total phenolics content of extract by SME from the hazelnut kernels was 4.82% by weight.

Keywords:

• antioxidants
• hazelnut kernel
• phenolics
• supercritical methanol extraction

Notes

^a daf = dry and ash free.