Salih Karasu

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.

Degradation Kinetics of Bioactive Compounds and Antioxidant Activity of Pomegranate Arils during the Drying Process

Abstract In this study, the drying kinetics of pomegranate arils, the degradation kinetics of some bioactive compounds, and changes in color values during the drying process were investigated. The drying process was performed by a forced air circulating oven at 55, 65, and 75°C. Drying times were calculated to be 1,020, 520, and 330 min, respectively. Effective moisture diffusivity values ranged from 5.39×10−11 to 1.70×10−10 m2 s−1 and increased with increases in temperature. Six different thin-layer drying models were applied to evaluate the goodness of the model. The degradation rate of bioactive compounds increased at higher temperatures; however, remaining amounts of phenolic, anthocyanin, and flavonoid compounds after drying were higher in samples dried at 75°C. The highest antioxidant capacity value was observed in the pomegranate arils dried at 75°C. While the L* values of pomegranate arils decreased after the drying process, the a* values increased.

Oleogels, a promising structured oil for decreasing saturated fatty acid concentrations: Production and food-based applications

ABSTRACT Oils and fats are widely used in the food formulations in order to improve nutritional and some quality characteristics of food products. Solid fats produced from oils by hydrogenization, interesterification, and fractionation processes are widely used in different foodstuffs for these aims. In recent years, consumer awareness of relation between diet and health has increased which can cause worry about solid fat including products in terms of their high saturated fatty acid and trans fatty acid contents. Therefore, different attempts have been carried out to find alternative ways to produce solid fat with low saturated fatty acid content. One of the promising ways is using oleogels, structuring oils with oleogelators. In this review, history, raw materials and production methods of the oleogels and their functions in oleogel quality were mentioned. Moreover, studies related with oleogel usage in different products were summarized and positive and negative aspects of oleogel were also mentioned. Considering the results of the related studies, it can be concluded that oleogels can be used in the formulation of bakery products, breakfast spreads, margarines, chocolates and chocolate-derived products and some of the meat products.