In this issue

Phenolic acids as antioxidants for frying

In this study, the potential of phenolic antioxidants to improve the frying performance of canola oil is explored [1465–1473]. Canola oil which was first treated to remove sterols and other minor components was used in order to evaluate the effect of the added phenolics including caffeic, dihydrocaffeic, gallic, vanillic, and ferulic acids, and ethyl ferulate. In addition, possible interactions of the added phenolics with endogenous antioxidants of canola oil were investigated in experiments where the phenolics were added together with the sterol or tocopherol fractions of canola oil. The phenolic antioxidants improved the stability of canola triacylglycerols during frying as judged by the formation of total polar components, 4-hydroxynonenal and volatile carbonyl compounds. In contrast to the endogenous canola tocopherols, canola sterols synergized with the added phenolics in protecting the frying oil, possibly through the formation of γ-oryzanols.

Aladedunye, F.A. and Przybylski, R. Antioxidative properties of phenolic acids and interaction with endogenous minor components during frying. Eur. J. Lipid Sci. Technol. 2011, 113, 1465–1473

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Turning waste oil into bioplastics

Możejko and coworkers [1550–1557] used waste rapeseed oil as a substrate for the microbial production of medium-chain polyhydroxyalkanoates, which have recently received a lot of attention as an alternative to plastics derived from petrochemicals. Two strains of Pseudomonaswere used in the study, yielding similar amounts of the polyhydroxyalkanoates. An important result of the study is the finding that the genes phaC1 and phaZ, coding a polymerase and a depolymerase, respectively, can be co-transcribed. This means that PHA synthesis is coupled with degradation in pseudomonads. The understanding of the genes involved in the regulation of PHA accumulation can open new avenues for engineering better PHA producers.

Możejko, J. et al. Waste rapeseed oil as a substrate for medium-chain-length polyhydroxyalkanoates production. Eur. J. Lipid Sci. Technol. 2011, 113, 1550–1557

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A graphical approach to finding good biodiesel

Here an interesting graphical approach to identifying biodiesel feedstocks is presented. From the literature, Viola et al. [1541–1549] collected the fatty acid compositions of 80 plant oils and predicted the properties of the derived methyl esters using empirical relationships. Two parameters were defined for each oil - the average number of carbon atoms in the FA chains (equation image) and the average number of double bonds (equation image) per molecule. From the two values, the viscosity and cetane number of biodiesel can be predicted. The range of equation image and equation image values where the biodiesel meets the EN 14214 standards is illustrated in a graph.

Viola, E. et al. Graphical method to select vegetable oils as potential feedstock for biodiesel production. Eur. J. Lipid Sci. Technol. 2011, 113, 1541–1549.

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