The optimal brewing conditions for Turkish green tea were determined on the basis of extracted catechins and sensory attributes. Green tea infusions were prepared at 75, 85 and 95°C with brewing times of 1, 2, 3, 5, 10, 20, 30 and 45 min. The amounts of epistructured catechins (EGCG, EGC, ECG, EC), non-epistructured catechins (C, GC, GCG) and caffeine in brewed tea samples were analysed. Sensory analyses were performed by nine trained panelists for infusion colour, taste, aroma and overall acceptability. Brewing at 85°C for 3 min was found to be the optimal condition, where the EGCG content was at a maximum of 50.69 mg/100 ml with the highest sensory scores. It was observed that the yield of epistructured catechins increased rapidly for the first 3-5 min of brewing at 85°C, and increased brewing time resulted in a decrease in the yield of epistructured catechins. The amount of nonepistructured catechins continued to increase with longer extraction times. Sensory scores for infusion colour, taste, aroma and overall acceptability were highest at 3 and 5 min brewing times at all temperatures. Sensory scores were very low for 30 and 45 min brewing at 85 and 95°C due to the bitter taste and dark colour.

Grape seed oils of seven native Turkish cultivars (namely Atfi, Mazruna, Black Kerküş, Zeyti, Verdani, Karfoki, and Kerküş) were evaluated for their fatty acids, tocols, phytosterols as well as total phenolics and oxygen radical absorbance capacity (ORAC) values. Among the fatty acids, linoleic acid (18:2ω6) was the most abundant (56.38–68.56%), followed by oleic acid (16.45–29.38%, 18:1ω9), palmitic acid (8.19–9.44%, 16:0), and stearic acid (3.74–4.98%, 18:0). Total tocopherols and tocotrienol amounts varied in the range of 102.30–305.43 and 251.47–468.22 mg/kg, respectively. Beta‐sitosterol was the most abundant sterol among grape cultivars whose concentration ranging from 64.19 to 71.62%. Total phenolic content ranged from 2.19 to 4.70 mg of gallic acid equivalents/100 g oil, being lowest in Zeyti and highest in Verdani. With respect to antioxidant activities, a large variation in ORAC values was observed among grape seed oils (ranging from 1048 µmol of Trolox equivalents (TE)/100 g in Karfoki to 2569 µmol of TE/100 g in Mazruna).Practical applications: The crude grape seed oils extracted from different cultivars are a good source of nutrients, fat‐soluble bioactives, and health‐promoting components.

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