Novel assisted/unassisted ultrasound treatment: Effect on respiration rate, ethylene production, enzymes activity, volatile composition, and odor of cherry tomato

Abstract Previous studies on the application of a novel multifrequency ultrasound washing treatment have proven to be effective in guaranteeing microbial safety, and enhancing the quality of cherry tomato. Nevertheless, there is still a need to evaluate the effect of these treatments on the metabolic activity, volatile profile, and sensorial quality of the fruit. This study evaluated the above parameters of cherry tomato treated with optimized assisted and un-assisted multifrequency ultrasound. The treatments slightly enhanced the enzyme activities and inhibit ethylene production and respiration rate. The results indicated that the treatment with 20/40 kHz and aqueous ozone (0.85 ± 0.2 mg/L) for 10 min enhanced and maintained the volatile compounds (VC). Out of the 44 identified VC, one had odor activity value > 1 and thereby considered as active aroma compound contributing significantly to the aroma of the sample. E-nose analysis indicated that alcohol, terpenes, and some aromatic compounds are the core indicators of the significant sensors. PCA showed that the processing methods had an influence on the flavor indexes of the tomatoes. The result verified that all the washing techniques did not result in a substantial negative effect on the tomato, and the treatment with ultrasound and ozone proved to be the best.