Influence of de-hulled rapeseed roasting on the physicochemical composition and oxidative state of oil

The effect of roasting time on the contents of bioactive compounds (tocopherols, phytosterols, phenolic compounds), antioxidant capacity and physicochemical properties of rapeseed oil pressed from de-hulled seeds was investigated. The de-hulled seeds were roasted at a temperature of 165 °C for 20, 40, 60, 80, and 100 min. The results of this study show that a roasting pre-treatment led to a gradual increase in canolol content (from 1.34 to 117.33 mg/100 g), total phytosterols (from 573.51 to 609.86 mg/100 g) and total carotenoids (0.82 to 2.41 mg/100 g), while only slight changes in the contents of tocopherols were noted. With the increase in roasting time a gradual increase in oxidative stability (from 4.27 to 6.85 h), and antioxidant capacity, seen mainly in the hydrophilic fraction of oil (from 0.32 to 2.30 mmol TEAC/l) was found. Although roasting resulted in the formation of primary and secondary oxidation products, the quality parameters of oils were within Codex Alimentarius limits

Endogenous Phenolics in Hulls and Cotyledons of Mustard and Canola: A Comparative Study on Its Sinapates and Antioxidant Capacity

Endogenous sinapic acid (SA), sinapine (SP), sinapoyl glucose (SG) and canolol (CAN) of canola and mustard seeds are the potent antioxidants in various lipid-containing systems. The study investigated these phenolic antioxidants using different fractions of canola and mustard seeds. Phenolic compounds were extracted from whole seeds and their fractions: hulls and cotyledons, using 70% methanol by the ultrasonication method and quantified using HPLC-DAD. The major phenolics from both hulls and cotyledons extracts were SP, with small amounts of SG, and SA with a significant difference of phenolic contents between the two seed fractions. Cotyledons showed relatively high content of SP, SA, SG and total phenolics in comparison to hulls (p < 0.001). The concentration of SP in different fractions ranged from 1.15 ± 0.07 to 12.20 ± 1.16 mg/g and followed a decreasing trend- canola cotyledons > mustard cotyledons > mustard seeds > canola seeds > mustard hulls > canola hulls. UPLC-tandem Mass Spectrometry confirmed the presence of sinapates and its fragmentation in these extracts. Further, a high degree of correlation (r = 0.93) was noted between DPPH scavenging activity and total phenolic content

Influence of thermal treatments on the antioxidant activity of hemp cake polar extracts

The effect of preheating temperature (X1), preheating time (X2) and the nature of the extracting solvents (X3) on the antioxidant activity of ultrasonic extracts of hemp cake was evaluated using a factorial design with a general linear multiple regression method using the three variables (X1, X2, and X3) and three levels including low (-1), intermediate (0) and high (+ 1). The results indicated that the extracting solvent and the preheating temperature levels were the principal effects influencing the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity (DPPH and FRAP). The highest level of preheating temperature (+ 1 = 180 °C) and extracting solvent (+ 1 = Ac80) were the optimal conditions for enhancing the extraction of the total phenolics and providing the highest antioxidant activity in hemp cake extracts. The interaction between temperature (X1), and the type of solvent (X3) significantly (p < 0.05) affected all the dependent variables examined.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Attenuation of sinapic acid and sinapine‐derived flavor‐active compounds using a factorial‐based pressurized high‐temperature processing

info:eu-repo/semantics/publishe

Effect of Solvent, Preheating Temperature, and Time on the Ultrasonic Extraction of Phenolic Compounds from Cold-Pressed Hempseed Cake

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