Effects of harvest maturity, refrigeration and blanching treatments on the volatile profiles of ripe “Tasti-Lee” tomatoes

Authors: XI, YU, YU - Beijing Technology And Business University; LI, QING - Beijing Technology And Business University; YAN, JIAQI - China Agriculture University; BALDWIN, ELIZABETH - Retired ARS Employee; Plotto, Anne; Rosskopf, Erin; Hong, Jason; Bai, Jinhe; LI, JIAN - Beijing Technology And Business University

Submitted to: Foods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/26/2021
Publication Date: 7/27/2021
Citation: Xi, Yu, Y., Li, Q., Yan, J., Baldwin, ., Plotto, A., Rosskopf, E.N., Hong, J.C., Bai, J., Li, J. 2021. Effects of harvest maturity and exposure to refrigeration and blanching of ripe fruit on volatile profiles of ‘Tasti-Lee’ tomatoes. Foods. 10:1727. https://doi.org/10.3390/foods10081727.
DOI: https://doi.org/10.3390/foods10081727

Interpretive Summary: Many consumers complain that the flavor of modern commercial tomatoes is lacking typical tomato flavor. Harvest before full ripe was often blamed. On the other hand, fruit harvested after mature green stage are believed possessing full ripening capacity to develop flavorful products. This research provided clear evidence that earlier harvests than turning stage did cause incomplete flavor quality in ripened fruit. Nevertheless, later harvests than turning stage also caused flavor deficiency after ripe. The results indicate that fruit fully developed at turning stage with the best flavor quality potential. However, later harvested fruit may be impacted by the field weather that leads to flavor deficiency. Registration and blanching in the kitchen caused critical flavor loss, and only the fruit harvested at turning stage showed tolerance to registration and blanching.

Technical Abstract: Most commercial tomato varieties for fresh market are harvested at the mature green stage, however may also be harvested at later stages for various reasons. Fruit are then ripened to red ripe before marketing. Refrigerated storage (chilling) and blanching (heating) treatments of ripe tomatoes are two common practices used in kitchen and foodservice situations. The interactive effects of six maturity stages and chilling/heating treatments on the volatile profiles of ripe tomatoes were studied. A total of 42 volatiles were identified, of which 19 compounds had odor activity values (OAV) equal to or greater than 1 (meaning that they contribute to tomato flavor) and of those, “green” and “leafy” aroma volatiles were most abundant. Chilling and heating treatments both suppressed overall volatile production, with chilling having the greater impact, regardless of harvest maturity. However, fruit harvested at the turning stage had the least volatile suppression by chilling and heat treatments in comparison with earlier or later harvested fruit, mostly in the fatty acid- and phenylalanine-derived volatiles. Volatiles derived from amino acids were promoted by heat treatment for fruit harvested at all maturities, and those derived from carotenoid and phenylalanine pathways and harvested at advanced harvest maturities (red and light red) were stimulated by chilling treatment. Volatile production is generally believed to be improved by delayed harvest, with vine-ripe being optimum. However, opposite results were observed: the maximum volatile production potential was reached in fruit harvested at the turning stage, while the later harvested fruit developed less abundant volatiles at red ripe stage, possibly because the later-harvested fruit had longer exposure to open field weather stress. The best harvest maturity recommendation was the turning stage where fruit developed abundant volatiles and were least impacted by chilling and heating treatments.