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In present study, cottonseed (Gossypium) varieties were evaluated for possible variation in quality attributes by using conventional and instrumental techniques. Physiochemical characteristics of seed and oils varied as: weight of individual seed (0.069-0.085 g), weight of 100 seeds (5.95-7.73 g), width (0.461-0.544 cm), length (0.736-0.915 cm), moisture (6.2-8.5%), oil content (12.01 to14.55%), refractive index at 40 o C (1.4661-1.4665) iodine value (IV) (93.90-105.76 gI 2 /100g), saponification value (SV) (181.83-190.55 mg KOH/g), peroxide value (PV) (1.0-6.0 m Eq/Kg), free fatty acids (FFA) (17.30-38.80 %) and induction period (IP) (1.95 -2.65 h), respectively. Analyzed varieties showed higher level of FFA (17.30-38.80%), while lower level of IP (1.95-2.65 h) respectively. Furthermore, GC-FID and FT-IR studies were carried out for quantitative and qualitative analysis of cottonseed oil. Analysis showed that most abundant fatty acid in each variety was linoleic acid (42.09-52.55 %) among unsaturated fatty acids, whereas palmitic acid (22.70-26.20 %) was major saturated fatty acid. Some band intensities of FTIR spectra highly correlated with the chemical properties of cottonseed oil such as IV, SV, PV, FFA and IP. In conclusion significant variation in physiochemical properties was observed among five cottonseed varieties, especially FFA and IP of cottonseed oil which is not good for the quality and edible point of view. This can be associated with the specific genetic variability and climatic conditions.

Introduction. The research was carried out to check the impact on the commercial refining of sunflower oil such as crude, neutralization, bleaching and deodorization on some specific physicochemical attributes that are essential for quality point of view and health. Materials and methods. Sunflower (SFO) oil samples (crude, neutralized, bleached and deodorized) were collected from the processing line unit from industrial oil company. In this study physicochemical parameters of SFO have been determined by official IUPAC and AOCS methods, while fatty acid composition was checked on GC-MS. Results and discussion. The obtained outcome of physical parameters showed that neutralization, bleaching and deodorization steps of crude SFO considerably decreased the moisture content (0.46-0.04%), color (2.8-1.1R, 28.0-11.0Y), freezing point (3.2-2.3) and smoke point (226.0-219.0), while some lesser change in refractive index was also observed. Moreover, in the case of chemical parameters for instance free fatty acids, saponification value and peroxide value were reduced from 0.56 to 0.06%, 178.5 to 177.2 mg KOH/g oil and 3.2 to 0.9 mEqO 2 /Kg oil, correspondingly. On the other hand refining steps did not showed significant impact on the iodine value (126.0-125.2 gI 2 /100g of oil) and fatty acid composition (total unsaturated fatty acids 89.06-90.91%). The most important influence during industrial processing was noted in soap contents, as these are generated during second step of refining. In present study soap content were reduced from 121.0 to 30.4 ppm during neutralization to deodorization steps. Conclusions. Among industrial process, deodorization step has greater influence on physicochemical attributes on the quality and stability of processed SFO.