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Magnesium silicate and basic magnesium carbonate were characterized and their application in the low temperature adsorption refining of fragrant rapeseed oil was investigated. The results showed that both materials had a loose porous structure, but their particle size distribution, active functional groups, crystallinity, specific surface area, pore volume, and pore size differed. Under the optimal adsorption refining conditions, magnesium silicate and basic magnesium carbonate reduced the phospholipid content from 4.18 to 0.83 and 1.57 mg/g, acid value from 1.67 to 0.88 and 0.90 mgKOH/g, yellow value from 38.2 to 32.1 and 36.2, and red value from 2.9 to 1.7 and 2.2, respectively. The use of these two magnesium salts did not significantly alter the composition of fatty acids and the content of tocopherol. The retention rates of total phytosterol by magnesium silicate and basic magnesium carbonate were 93.6% and 95.9%, respectively. The retention rates of total phenol were 88.9% and 93.9%, respectively. The adsorption refining process proved to be advantageous in purifying fragrant rapeseed oil while maintaining the dominant flavor components relatively unchanged (P < 0.05). As a result, these two magnesium salts have the potential to be used during the low temperature adsorption refining process of fragrant rapeseed oil. • The two magnesium salts both had good adsorption refining effect on rapeseed oil. • Magnesium silicate showed superior adsorption refining capacity than the other. • Retention rates of micronutrients by the two magnesium salts were very promising. • The refining by the two magnesium salts purified the flavor of the rapeseed oil. [ABSTRACT FROM AUTHOR]

The oil and protein of dehulled cold-pressed double-low rapeseed cake was extracted by an aqueous enzymatic process. The rapeseed cake was treated by the chosen combined enzymes of Viscozyme L and Alcalase 2.4L (VLA,1:1,w/w). Preliminary experiments and Response Surface Methodology (RSM) were used to study the effects of enzyme concentration, incubation time and water-to-cake ratio on the extraction yield of oil and protein. This is how the desirable conditions were obtained. Transmissive electron microscope photo showed that after cold-pressing the cell structure of rapeseed was partly damaged while dehulling had little effect on the cell structure of rapeseed. In RSM experiments water-to-cake ratio showed significant effects on the extraction of oil and protein (P<0.05),while incubation time only showed significant effects on protein yield (P<0.05).The desirable conditions were as follows: 1.0% concentration (w/w) of VLA; water-to-cake ratio(w/w),6:1; 80 min incubation time. Under this condition, the extraction yield of protein and oil were 82.10% and 71.89%, respectively. Through combining both the cold-press and the aqueous enzymatic processes together, the total oil yield reached 91.6%, which is higher than the normal cold-press process or the aqueous enzymatic extraction process alone. [ABSTRACT FROM AUTHOR]

The objectives of this study were to obtain the optimal technical parameters of steam explosion for rapeseed and investigate the effects of pretreatment on the bioactive components and characteristics of three diverse samples of Brassica seed (Brassica napus , B. juncea and B. rapa) and their products. Under the optimal conditions, Brassica napus formed the largest amount of canolol, namely, 1210.10 mg/kg; B. rapa formed the smallest amount, namely, 82.70 mg/kg; and the canolol content was 2110.00 mg/kg in Brassica napus oil. Meanwhile, compared to the traditional cold-pressed rapeseed oil, the total tocopherol and phytosterol contents in Brassica napus , B. rapa and B. juncea oil increased by 5.3%, 4.8%, and 7.4% and 2.1%, 3.2%, and 5.1%, respectively. Steam explosion pretreatment also significantly affected the total phenolic contents and antioxidant capacities of the three types of rapeseeds and their processed products (P < 0.05). In addition, by steam explosion pretreatment, the EAA contents of B. rapa and B. juncea rapeseed cakes increased by 2.22% and 4.49%, respectively. These findings will provide data support and a reference basis for the application and development of steam explosion technology to rapeseeds of various types. • By steam explosion, Brassica napus rapeseed formed the largest amount of canolol. • Steam explosion increased the contents of bioactive components of rapeseed oil. • Steam explosion enhanced the essential amino acid contents of rapeseed cakes. [ABSTRACT FROM AUTHOR]

A new method for rapeseed oil preparation named synchronous pressing and refining after solid-phase preadsorption technology was investigated. Rapeseed and adsorbents were first mixed evenly to form premixes, and the product oils were then obtained by direct pressing and filtering. The phospholipid content, acid value, a* value, chlorophyll, carotene, polyphenol contents of crude oil increased, while L* and b* values decreased with increasing squeezing chamber temperature. A moderate adsorbent dosage and temperature could improve the refining effects. Silicon dioxide had the highest dephosphorization and deacidification rates of 95% and 42%, respectively, when the dosage was 30 g/kg at 130 °C. Activated clay decreased the chlorophyll and carotene contents by 75% and 38%, respectively. Sucrose fatty acid ester had dephosphorization and deacidification rates of 67s% and 41%, respectively. Ascorbic palmitate had a dephosphorization rate of 74% and retained polyphenols intactly. This technology would not affect the oil yield and could decrease the peroxide value of rapeseed oil. It realized the simultaneous completion of pressing and refining with the advantages of a short preparation time and environmental sustainability. • The method realized the simultaneous completion of pressing and physical refining. • The new oil preparation method has no significant effect on oil yield. • Silicon dioxide had a better refining effect than other adsorbents in this method. • Ascorbic palmitate had a high dephosphorization rate and polyphenol retention rate. [ABSTRACT FROM AUTHOR]