Extraction of polyphenols from berry fruits by combination of subcritical pressure extraction and enzymatic hydrolysis

Abstract

The extraction of phytochemicals has played an important role in the manufacture of functional foods. While many extraction methods have been developed, their efficiency is low. Other disadvantages is involving high energy consumption, much time, low selectivity. Moreover, many heat-sensitive phytochemicals may be degraded by solvent or heat extraction. A combination of subcritical pressure extraction and enzymatic hydrolysis (SPE-EH) is a relatively new extraction technique that is programmable and thus is very reproducible with respect to product development. The aim of this research was to develop the practical application of high hydrostatic pressure technology to extract polyphenols from fresh berry fruits including blackcurrants and mulberries with treatment of pectinase. The yields of extraction was increased upto 60% in blackcurrants and more than 3 times for some phenolic acids in mulberries. Optimum conditions for the extraction of polyphenols by using SPE-EH was treatment with 50 MPa, 40℃, 30 min and 100 Unit of enzymes. This technique may provide a safe, simple, highly efficient and cost-effective method of extraction without using solvent or excessive heat. Under the SPE-EH condition, there are significantly higher yields of polyphenols, total phenolics and total flavonoids than those obtained with no enzymatic or high pressure treatment.