SUMMARY:There is a growing interest in cold-pressed oils because they present high contents of bioactive compounds. These oils have the characteristic properties of seeds and are specific products of their regions. The aim of this study was to determine the compositions and contents of fatty acids, phytosterols, squalene, tocols, phenolic acids, carotenoids and phenolic bioactives, and the free radical scavenging as well as antioxidant activities of coldpressed pumpkin (Cucurbita pepo L.) seed oils. Oil samples from raw pumpkin seeds cultivated in four different central Anatolia regions of Turkey were prepared using a laboratory screw-pressing machine. The results indicate that coldpressed pumpkin seed oils (PSO) have excellent quality with high contents of polyunsaturated fatty acids (%∑PUFAs) (53.60 ±0.06−53.73 ±0.05), total phytosterols (782.1±9.7-805.2 ±11.3 mg/100 g oil), squalene (591.3±10.6-632.5±11.4 mg/100 g oil), tocols (97.79 ±0.76−94.29 ±0.34 mg/100 g oil), phenolic acids (22.73 ±0.41-23.98 ±0.46 mg/100 g oil), carotenoids (6.95 ±0.03-7.60 ±0.03 mg/100 g oil), total phenolics (3.96 ±0.13 -5.82±0.15 mg GAE/100 g), free radicalscavenging activity (5.70 ±0.13−7.35 ±0.15 mg GAE/100 g) and total antioxidant activity (26.67±0.97−38.89±1.41 mg GAE/100 g) values. Thus, this study demonstrates that the cold-pressed PSOs from the central Anatolia regions of Turkey are an excellent source of natural bioactive compounds, free of chemical contaminants and nutritious.KEYWORDS: Antioxidant activity; Bioactive compound; Cold-pressed oil; Cucurbita pepo L.; Phenolic acid; Tocol profile RESUMEN: Aceites de semillas de calabaza prensados en frío (Cucurbita pepo L.) de la región central de Anatolia en Turquía: Caracterización de fitosteroles, escualeno, tocoles, ácidos fenólicos, carotenoides y compuestos bioactivos de ácidos grasos. Existe un interés creciente en los aceites prensados en frío, ya que presentan altos contenidos de compuestos bioactivos. Estos aceites tienen las propiedades características de las semillas y son productos específicos de las regiones. El objetivo de este estudio fue determinar las composiciones y contenidos de ácidos grasos, fitoesteroles, escualeno, tocoles, ácidos fenólicos, carotenoides y bioactivos fenólicos, la actividad de eliminación de radicales libres, así como las actividades antioxidantes de aceites de semillas de calabaza prensados en frío (Cucurbita pepo L.). Las muestras de aceite de semillas de calabaza cultivadas en cuatro regiones diferentes de Anatolia central de Turquía se prepararon utilizando una máquina de laboratorio de prensado mediante tornillo. Los resultados indican que los aceites de semilla de calabaza prensados en frío (PSO) tienen una excelente calidad, con altos contenidos de ácidos grasos poliinsaturados (%ΣPUFA) (53,60±0,06-53,73±0,05), fitoesteroles totales (782,1±9,7-805,2±11,3 mg/100 g de aceite), escualeno (591,3 ± 10,6-632,5 ± 11,4 mg/100 g de aceite), tocols (97,79±0,76-94,29±0,34 mg/100 g de aceite), ácidos fenólicos (22,73 ± 0,41-23,98 ± 0.46 mg/10...

Blending polyunsaturated oils with highly saturated or monounsaturated oils has been studied extensively, however in literature there is negligible information available on the blending of refined cottonseed oil (CSO) with palm olein oil (POO). Blending could enhance the stability & quality of CSO during frying process. In the present study, the effects of frying conditions on physicochemical properties of the palm olein-cottonseed oil blends (1:0, 3:2, 1:1, 2:3 and 0:1, w/w) were determined & compared to the pure oils. The frying process of frozen french fries was performed in duplicate at 170 ±5°C for 10 h without interruption. The oil degradations were characterized during deep-frying applications; peroxide, free fatty acid and iodine value by standardized methods, fatty acid profile by GC/FID, polar and polymeric compounds by HPSEC/ELSD technique. The present study clearly indicated that the oxidative and frying performances of pure POO and CSO significantly improved by blending application. Results clearly indicated that the frying performance of CSO significantly improved by the blending with POO. Except that FFA content, all the physicochemical variables were significantly influenced International Journal of Food PropertiesA c c e p t e d M a n u s c r i p t 2 by type of pure and blend oils. By increasing the proportion of POO in CSO, levels of polyunsaturated fatty acids (PUFA) decreased, while saturated fatty acids content increased.Progression of oxidation was basically followed by detecting polar and polymeric compounds.The fastest increments for polar and polymeric compounds were found as 6.30% level in pure CSO and as 7.07% level in 40%CSO:60% POO blend oil. The least increments were detected as 5.40% level in 40%CSO:60% POO blend and 2.27% level in 50%CSO:50% POO blend oil.These levels was considerably below the acceptable levels recommended by the official codex. Therefore, the present study suggested that blending of CSO with POO provided the oil blends (50%CSO:50%POO and 40%CSO:60%POO, w/w) with more desirable properties for the human nutrition.

This paper describes the feasibility of attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy combined with multivariate data analyses for rapid determination of cold-pressed wheat germ oil (WGO) adulteration. Thirty-six pure edible oils, as well as 216 binary blends of WGO adulterated with cheaper refined oils, sunflower (SFO), and soybean oil (SBO) (1-50%) were analyzed by using ATR-FTIR spectroscopy in combination with PCA, LDA, SIMCA, and PLSR analyses. SIMCA models provide excellent classification for pure cold-pressed WGO and refined edible oil samples, with 95% significance level. The classification limits for detection of SFO and SBO adulterations in WGO were below 1%. Furthermore, a total of 100% of studied samples were correctly classified on the basis of their origin in calibration and in cross-validation by LDA models. Under the optimum conditions, the PLS-R plots of actual versus predicted values exhibited high linearity (R 2 > 0.9990). The content of SFO and SBO adulterants has been successively quantified using PLSR at levels < 0.56% and < 0.99% in an unknown mixture. RMSEC and RMSECV values for the binary mixtures of WGO-SFO were between 0.56-1.98% and 0.68-4.46%, for the binary mixtures of WGO-SBO were between 0.99-1.77% and 1.09-5.12%, respectively.

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The main goal of the present study was (i) to determine the formation of degradation products in cottonseed oil (CSO) blends during deep frying process by adsorption and high performance size exclusion chromatography techniques and (ii) to evaluate the impacts of food additives on total polar (TPC) and polymeric compound (PTAG) formation using a chemometric approach. In order to prepare the frying CSO blends; ascorbic palmitate, mixed tocopherols, dimethylpolysiloxane, lecithin and sesame oils were used as additives. To determine the real impacts of additives, a quarter-fraction factorial experimental design with two levels and five factors was used. The changes in TPC and PTAG data were carefully evaluated during 10 h of frying at 170 ± 5°C with normal distribution (ND) graphs and analyzed using a one-way analysis of variance (ANOVA), followed by Tukey's Post-hoc test (a = 0.05). The results indicated that the increasing values for TPC and PTAG during the frying processes for all blends, TPC and PTAG contents reached maximum levels of 16.37 and 6.01 % respectively, which are below the limit values stated by official authorities for the quality assessment of frying oils. The ANOVA test results were in good agreement with ND graphs and data indicated that the impact of mixed tocopherols was significant for TPC formation, meanwhile the impact of lecithin and ascorbic palmitate 9 dimethylpolysiloxane were significant for PTAG formation. Thus, the present study should be considered to be a very useful guide for developing new frying oil formulations based on CSO by using food additives.

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