Pressurized Liquid Extraction of Phenolic Compounds from Fruit Pomaces


Tezin Türü: Doktora

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Gıda Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2006

Tezin Dili: İngilizce

Öğrenci: İncinur Hasbay Adil

Asıl Danışman (Eş Danışmanlı Tezler İçin): Alev Bayındırlı

Eş Danışman: Meryem Esra Yener

Özet:

In this study, extraction of phenolic compounds from sour cherry, peach and apple pomaces using high pressure extraction (HPE) and subcritical CO2 extraction (SCE) was investigated considering total phenolic content (TPC) and antiradical efficiency (AE). Different combinations of pressure (50, 125, 200 MPa), temperature (20, 40, 60C), solid/solvent ratio (0.05, 0.15, 0.25 g/ml) and extraction time (10, 25, 40 min) were used for HPE according to the Box-Behnken experimental design. The variables used for SCE were pressure (20, 40, 60 MPa), temperature (40, 50, 60C), ethanol concentration (14, 17, 20 wt%) and extraction time (10, 25, 40 min). For HPE, TPC and AE at the optimum conditions were 3.80 mg gae/g sample and 22 mg DPPH˙/g sample for sour cherry pomace, 0.93 mg gae/g sample and 6.40 mg DPPH˙/g sample for peach pomace and 2.08 mg gae/g sample and 10.80 mg DPPH˙/g sample for apple pomace, respectively. For SCE, TPC and AE at the optimum conditions were 0.60 mg gae/g sample and 2.30 mg DPPH˙/g sample for sour cherry pomace, 0.26 mg gae/g sample and 1.50 mg DPPH˙/g sample for peach pomace and 0.47 mg gae/g sample and 3.30 mg DPPH˙/g sample for apple pomace, respectively. Efficiency of HPE and SCE methods was compared with solvent extraction (SE). TPC and AE of the extracts obtained by HPE were close to those obtained by SE but the efficiency of SCE was low compared to HPE and SE. SCE was a better extraction method for apple and peach pomaces compared to sour cherry pomace.