Ultrasound-assisted solvent extraction of carotenoids from rapeseed meal was investigated and evaluated by response surface methodology. We have compared the yields of carotenoids by using five different solvent systems, and found that the highest yield can be achieved under petroleum ether/acetone (v/v = 1/1). We have further tested the effect of ultrasonic power, modulation frequency, duration, temperature, liquid to material ratio and extraction times on the yield of carotenoids by adopting Plackett-Burman and Box-Behnken experimental design methods. Optimal conditions for obtaining high yield of carotenoids were as follows: temperature 49.6C, liquid to material ratio 41.4 mL/g, duration 48.5 min, ultrasonic power 252.9 W (240 W was used in the control experiments). Under the above conditions, average carotenoid yield was 0.1577 ± 0.0014 mg/g, and the extraction percentage was 79.61 ± 0.71%. The results indicated that rapeseed meal was a promising alternative source for carotenoid extraction. PRACTICAL APPLICATIONSCarotenoids are one of the most common natural food colorants and exist widely in plants, bacteria, fungi and animals. Ultrasound has been utilized to assist the solvent extraction of bioactive compounds from vegetal materials, and led to high yield of desired products. In the present study, we have investigated ultrasoundassisted extraction of carotenoids from rapeseed meal using the response surface methodology. In order to obtain the highest yield of carotenoids, we have examined various operational parameters, such as extraction temperature, liquid to material ratio, solvent composition, extraction time and modulation frequency, and have established optimal conditions to extract carotenoids from rapeseed meal. Our results provide basic knowledge on the extraction of carotenoids from rapeseed meal, which serves as a promising bioresource.

The antioxidative properties of rapeseed meal extract (RME; 0.014%, 0.028%, 0.042%, 0.056% and 0.070% w/w) were evaluated in soybean oil. Soybean oil oxidation was tested by measuring peroxide value, thiobarbituric acid reactive substances (TBARS) value, carbonyl value, acid value, conjugated diene value, p-anisidine value, iodine value and viscosity during accelerated storage at 68C for 19 days as compared with butylated hydroxyanisole (BHA) 0.014% (w/w). Results from different parameters were in agreement with each other; soybean oil containing RME 0.014% was better than soybean oil with BHA and control samples, with the exception of TBARS, which suggested higher efficiency of RME 0.028% over BHA. Antioxidative influence of soybean oil was not increased with increasing concentration of RME during 19 days of storage. Results revealed that RME added to soybean oil can retard the process of lipid peroxidation during storage. PRACTICAL APPLICATIONSOils are important functional components of foods and have a significant effect on the quality of foods. They not only contribute to flavor, odor, color and texture, but also confer a feeling of satiety and palatability to foods. However, the major problem in these oils lies in lipid oxidation during storage or food processing. The objective of this study was to evaluate the potentiality of rapeseed meal extract (RME) used as antioxidant. The antioxidative effects of RME was investigated in soybean oil under accelerated conditions and compared with butylated hydroxyanisole (BHA) during storage.

To reduce the indiscriminate use of pesticides and extend the postharvest shelf life of peach fruit (Prunus persica, cv. Baihua) from southeast China, mainly the microbial antagonism of indigenous yeasts was studied and applied in the construction of composite film. In this study, 14 yeast strains of 9 genera were screened out from the surface of peaches by isolation, purification, cultivation, and identification. Through an experimental analysis of the in vitro inhibition zone and the in vivo colonizing capacity, 1 × 108 CFU mL−1 of Candida oleophila sp-ELPY12B and Cryptococcus laurentii sp-ELPY15A proved most efficient against the major pathogens and were chosen as candidate fungicides. In combination with Na-alginate film (0.4% glycerin as the plasticizer and 0.1% Tween-80 as the emulsifier), the preservative effects of these composite-treated groups also showed the best antifungal effects, which significantly delayed the postharvest preservation period by about 6–7 d under an ambient temperature of 25 ± 3 °C and a relative humidity of 50–70%.