Improvement in the aroma of watermelon juice by vacuum blending with linoleic acid addition.

Watermelon juice is favored by a large number of consumers as a summer heat-relieving tool. This paper aims to analyze the effect and improvement of linoleic acid combined with vacuum blending on the aroma of watermelon juice using modern molecular sensory technology. A total of 100 volatile organic compounds were identified, mainly small-molecule aldehydes, alcohols and ketones. The concentrations of (Z)-2-nonenal in vacuum blending watermelon juice with 5, 25, 50, and 250 μg/g linoleic acid were 2.64, 3.04, 7.68, and 19.8 times those of untreated juice, respectively. Notably, the aldehyde concentration of 250 μg/g linoleic acid combined with vacuum blending watermelon juice was 19.76 times that of untreated juice, which contributed to the sweet and green aromas of watermelon juice. The findings of the present study suggest that vacuum blending with the addition of 250 μg/g linoleic acid may be a method to improve the overall aroma of watermelon juice.