Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Gıda Mühendisliği Bölümü, Türkiye
Tezin Onay Tarihi: 2014
Tezin Dili: İngilizce
Öğrenci: ÖZGE YEĞİN
Asıl Danışman (Eş Danışmanlı Tezler İçin): İlkay Şensoy
Eş Danışman: Zümrüt Begüm Ögel
Özet:Red pepper pulp was added as a functional ingredient to the extrudates. Effects of extrusion on the functional properties of the red pepper pulp added corn grit extrudates were investigated. Antioxidant activity, total phenolic content, and the amounts of xanthophyll carotenoids in the product, such as β-cryptoxanthin and zeaxanthin, were determined before and after the extrusion process. In vitro bioaccessibility of these carotenoids from the extrudates and the feed were also investigated. Starch gelatinization (with DSC), pectin, protein, moisture and ash contents were determined for the feed and the product. Two different temperature profile were applied for the barrel zones during extrusion: 80°C, 90°C, 100°C and 130°C (die: 121°C) and 80°C, 105°C, 130°C and 160°C (die: 142°C). Screw speed (225 rpm) and feed flow rate (36 g/min) were kept constant. Feed moisture content was 25 ± 0.5%. Total phenolic content of the samples were found to decrease about 41.72% and 47.68% whereas antioxidant activity of the samples were found to decrease about 28.92% and 22.89% after 130°C and 160°C last zone temperature extrusion process, respectively. No gelatinization peak was observed on DSC thermograms after extrusion whereas a peak was observed before extrusion. High performance liquid chromatography (HPLC) analysis showed a decrease in β-cryptoxanthin content about 17.53% and 28.87% whereas a reduction was observed in zeaxanthin content about 49.83% and 40.07% after 130°C and 160°C last zone temperature extrusion process, respectively. There was not statistically significant difference between in vitro bioaccessibility of β-cryptoxanthin and zeaxanthin of feed and extrudates. The results suggest that red pepper pulp can be added as a functional ingredient to develop new functional extruded food products.