Umit Gecgel

Recovery potential of cold press byproducts obtained from the edible oil industry: physicochemical, bioactive, and antimicrobial properties.

Physicochemical, bioactive, and antimicrobial properties of different cold press edible oil byproducts (almond (AOB), walnut (WOB), pomegranate (POB), and grape (GOB)) were investigated. Oil, protein, and crude fiber content of the byproducts were found between 4.82 and 12.57%, between 9.38 and 49.05%, and between 5.87 and 45.83%, respectively. GOB had very high crude fiber content; therefore, it may have potential for use as a new dietary fiber source in the food industry. As GOB, POB, and WOB oils were rich in polyunsaturated fatty acids, AOB was rich in monounsaturated fatty acids. Oil byproducts were also found to be rich in dietary mineral contents, especially potassium, calcium, phosphorus, and magnesium. WOB had highest total phenolic (802 ppm), flavonoid (216 ppm), and total hydrolyzed tannin (2185 ppm) contents among the other byproducts. Volatile compounds of all the byproducts are mainly composed of terpenes in concentration of approximately 95%. Limonene was the dominant volatile compound in all of the byproducts. Almond and pomegranate byproduct extracts showed antibacterial activity depending on their concentration, whereas those of walnut and grape byproducts showed no antibacterial activity against any pathogenic bacteria tested. According to the results of the present study, walnut, almond, pomegranate, and grape seed oil byproducts possess valuable properties that can be taken into consideration for improvement of nutritional and functional properties of many food products.

Bioactive Properties, Fatty Acid Composition and Mineral Contents of Grape Seed and Oils

The oil content of grape seed samples changed between 4.53% (Adakarasi) and 11.13% (Sauvignon blanc). While the linoleic acid contents of grape seed oils ranged from 47.34% (Sangiovese) to 72.91% (Cinsaut), the oleic acid contents varied between 13.35% (Cabernet Sauvignon) and 26.30% (Sangiovese) (p < 0.05). Also, the palmitic acid and stearic acid contents of grape seed oils ranged from 7.15% (Cinsaut) to 16.06% (Sangiovese) and from 2.43% (Narince) to 6.55% (Sangiovese) respectively (p < 0.05). The flavonoid contents of the seeds changed between 263.53 (mg CE/g) and 1 706.00 (mg CE/g) (Cabernet Sauvignon). Total phenols were found to be between 6 711.14 (mg GA/g extract) (Sangiovese) and 8 818.69 (mg GA/g extract) (Narince). The linoleic contents of oils changed from between 47.34% (Sangiovese) and 72.91% (Cinsaut). The K contents of the grape seed samples changed between 4 347.80 mg/kg (Cabernet Sauvignon) and 9 492.60 mg/kg (Gamay) (p < 0.05). The Fe contents of seeds were found to be between 29.96 mg/kg (Narince) and 73.82 mg/kg (Sangiovese). As a result, the current study shows that grape seeds are useful for human nutrition due to their components.

Comparison of Fatty Acid Composition between Female and Male Japanese Quail Meats

The objective of the present study was to compare the proximate analysis, fatty acids composition, omega fatty acids, trans fatty acids (TFAs), and ratio of the total poly unsaturated fatty acid (PUFA) and total saturated fatty acid (SFA) of female and male quail meats. Significant differences were not observed between pH, crude fat, moisture, and ash content of female and male quail meats (). The male quail meat had higher fat and ash contents and lower moisture content than those of the female quail meat. The pHs of male and female quail meat were found to be 6.22 and 6.21, respectively. The results of the fatty acid composition analysis showed that C18:1 (42.14–41.23%), C16:0 (24.31–25.76%), C18:2 (13.82–13.42%), and C18:0 (7.49–7.32%) were found as the major fatty acids in the female and male quail meats. Total TFAs, SFA, monounsaturated fatty acids (MUFA), and PUFA content of the female and male quail meats were found to be 2.79–2.82%, 33.22–34.65%, 49.70–48.72%, and 14.29–13.81%, respectively.

Physicochemical Properties of Starch from a Cereal-Based Fermented Food (Tarhana)

Tarhana is a traditional fermented food product in Turkey. There is limited research on starch characteristics of tarhana. In this study, starch properties of various home-made tarhana samples have been investigated. Starch content ranged from 59.64 to 69.95 and there were significant (P<0.05) differences in starch damage (3.78-10.84%). The starch pasting and gelatinization of the tarhana samples also showed significant (P<0.05) differences. Estimated glycemic indexes ranged from 86.16 to 102.54 and are all considered high glycemic index. Amylose content of the tarhana also showed significant (P<0.05) variation (20.70-29.03%). There were significant (P<0.05) differences in the molecular mass of the tarhana starch. The molecular mass of the high molecular weight amylopectin ranged from 2-15 million daltons and the amylose ranged from 300 thousand to 2.4 million daltons. Overall, there were significant (P<0.05) differences in chemical composition and starch characteristics of tarhana samples.

Determination of Bioactive Compounds and Mineral Contents of Seedless Parts and Seeds of Grapes

In this study, phenolic compounds, minerals, total flavonoids, total phenolic contents and antioxidant activities of the seedless parts (pulp+skin) and seeds of table and wine grapes were determined. Also, the total oil, tocopherol contents and fatty acid composition of seed oils of table and wine grapes were investigated. The highest total phenolic content of the grape pulp was found in Trakya ilkeren (199.063mg/100 g), while total flavonoid and antioxidant activity of the pulp was determined at a high level in Red Globe (6.810 mg/g, 90.948%). Antioxidant activity, and the total phenolic and flavonoid contents of grape seeds varied between 86.688 and 90.974%, 421.563 and 490.625 mg GAE/100 g, and 90.595 and 145.595 mg/g respectively (p < 0.05). Generally, the main phenolic compounds of all grape pulps and seeds were gallic acid, 3,4- dihydroxybenzoic acid, (+)-catechin and 1,2-dihydroxybenzene. In addition, the oil contents of grape seeds ranged from 5.275 (Cavus) to 13.881% (Cinarli karasi) (p < 0.05). The major fatty acids of grape seed oils were linoleic, oleic and palmitic acid. The seed oil of the Trakya ilkeren variety was rich in tocopherols in comparison with the other varieties. The major minerals of both the seedless parts and the seeds were determined as K, Ca, P, S, Mg.