Protein precipitating capacity and antioxidant activity of Turkish Tombul hazelnut phenolic extract and its fractions.

Natural (raw) hazelnut was extracted with 80% (v/v) acetone to obtain crude phenolic extract that was then fractionated for elution of low-molecular weight (LMW) and high-molecular weight (HMW) fractions. LMW fraction was further purified (LWM-FP) to remove sugars and organic acids. The crude extract and its fractions were determined by measuring their protein precipitating capacity (PPC) using two different proteins [bovine serum albumin (BSA) and gelatin], molecular weights, total phenolics, condensed tannins, and various antioxidant activities.