Impact of early harvesting and two cold storage technologies on eating quality of red ripe tomatoes

Abstract

Tomato fruits of cv. Caramba harvested at the pink ripening stage were cold stored for 4 and 7 days at 6 °C, then allowed to fully ripen at ambient temperature, and finally evaluated for eating quality, and compared with fruit fully ripened on the vine. In addition, fruits harvested at full ripeness were subjected to cold storage at 6 °C by a conventional or the innovative passive refrigeration PRS™ system for 2, 4, and 7 days, and then evaluated. Tomato quality evaluation included sensory, chemical (volatile compounds, sugars, and organic acids), and physical (flesh texture and skin colour) attributes. Fruit harvested at the pink stage, and then subjected to cold storage, when attained full external red colour showed less intense tomato odour, red ripe tomato odour, and flavour when compared to fruit fully ripened on the vine, and, at the same time, developed a perceptible mould off-odour. These differences were consistent with those observed in the levels of aroma compounds and fermentation metabolites. Main effects associated with cold storage of red ripe fruits by both conventional and passive refrigeration were increased skin toughness and decreased sourness. Passive refrigeration caused a more pronounced toughening of the skin, but no development off-odours were detected. Analysis of alteration of volatile synthesis confirmed recent findings on the molecular mechanism underlying chilling-induced loss of flavour in tomatoes.