A comparative study on the effect of microwave and conventional oven heating on the quality of flaxseeds

This study was to evaluate the effects of microwave and conventional oven heating on the amount of hydrogen cyanide, oil and protein properties, and volatile compounds of flaxseed. All the heating treatments effectively reduced the contents of hydrogen cyanide. Notably, oven heating at 150 degrees C for 30 min increased the peroxide value by more than 10 folds, while microwave heating at 860W for 8 min only caused slight increase at the similar color. In addition, SDS-PAGE showed that the oven heating at 150 degrees C caused a more prominent decrease in the intensity of the 40-60 kDa and 22.0-30.0 kDa bands than microwave heating at 860 W. Furthermore, both oven heating at 150 degrees C and microwave heating at 860 W remarkably increased the kinds and amounts of the volatiles, such as pyrazines, alkanes, aldehydes, which could be due to Maillard reaction and lipid oxidation. Based on above analysis index, principal component analysis (PCA) was performed to further analysis comprehensive quality of flaxseeds, indicating microwave heating (860 W for 8 min) and oven heating (150 degrees C for 30 min) of flaxseeds showed similar properties. Collectively, the results indicated the feasibility of microwave treatment as an alternative to the conventional oven heating to process the flaxseeds.

Automated summary

The study evaluated the effects of microwave and conventional oven heating on flaxseed properties, including hydrogen cyanide content, peroxide value, and volatile compounds. Both heating methods effectively reduced cyanide levels, with microwave heating causing minimal changes in color compared to significant increases with oven heating. In terms of protein properties, oven heating resulted in a more prominent decrease in certain protein bands compared to microwave heating. Furthermore, both heating methods increased the variety and amount of volatile compounds, potentially due to Maillard reaction and lipid oxidation. Overall, microwave heating was shown to be a feasible alternative to conventional oven heating for processing flaxseeds.