Influence of shooting period and extraction conditions on bioactive compounds in Turkish green tea

Abstract The aim of this study was to investigate the influence of different extraction temperatures (75, 85 and 95 °C) and times (3, 5, 10, 15 and 20 min) on bioactive compounds in Turkish green tea produced and classified as Turkuaz, Kardelen and Antikyeşil by ÇAYKUR (the Turkish Tea Board) over three shooting periods. Green tea extracts were subjected to analyses of extraction yield, antioxidant capacity, total phenolic and flavonoid contents, and the phenolic and flavonoid composition. Total phenolic and flavonoid contents and the antioxidant capacity of samples increased when extraction temperatures and times were increased. Extraction yield, total phenolics, total flavonoids and the antioxidant capacity of the green teas were found in the range of 21.52-37.40 g 100 g-1, 68.13-131.31 mg GAE g-1 dw, 17.97-32.04 mg CE g-1 dw and 0.48-1.16 mg dw mg-1 DPPH, respectively. The average amounts of individual catechins, i.e. catechin, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, gallocatechin gallate, gallocatechin and catechin gallate were found in the range of 8.91-17.09, 4.29-9.55, 28.03-59.42, 8.02-14.61, 38.05-69.66, 2.53-18.53, 2.30-12.97 and 0.04-1.78 mg g-1 dw, respectively

THE EFFECT OF HEATING METHOD AND FORMULATION ON MARMALADE QUALITY PRODUCED FROM ROSE HIP PULP

Some chemical properties of rose hip pulp obtained from a commercial firm were determined and processed to marmalade by using 40/60 and 45/55 pulp/sugar ratio under the atmospheric and vacuum conditions. Two level of citric acid were added into the samples. Measured properties of the pulp as follows: total dry matter 12.39 %, soluble dry matter 10.63 %, titration acidity 0.61 %, pH 3.54, ascorbic acid 1170.9 mg/100 g, total ash 0.72 %, HMF 0.29mg/100 g, total sugar 10.58 %, reducing sugar 5.24 % and sucrose 5.34 %. Also, in marmalade following values were obtained: total dry matter 70.38-71.97 %, soluble dry matter 67.69-69.10 %, titration acidity 0.55-0.73 %, pH 2.97-3.31, ascorbic acid 109.29-153.85 mg/100 g, total minerals 0.30-0.34 %, HMF 0.45-3.36 mg/100 g, total sugar 64.10-64.93 %, reducing sugar 5.18-6.97 % and sucrose 37.83-56.78 %. L, a and b colours values belong to marmalades were also determined. In the marmalades produced under vacuum condition, inversion was insufficient but low HMF and better protected ascorbic acid were determined