TEMPORAL CHANGES IN TEXTURAL AND TASTE-RELATED CHARACTERISTICS OF SEVEN UK-GROWN SH-2 SWEETCORN CULTIVARS STORED UNDER CONTROLLED ATMOSPHERE CONDITIONS

Abstract

Sweetcorn is an important crop in the fresh vegetable market. As consumption increases, greater knowledge is required on quality parameters (viz., texture, concentration of sugars) which are intimately associated to consumer acceptability. Deterioration of the quality of sweetcorn after harvest is rapid even for sh-2-types (super sweet) which tend to deaden the conversion of sugars to starch. Storage at low temperatures after harvest and/or under CA storage conditions, is essential for the maintenance of important chemical and physical characteristics of super sweetcorn. The current study aimed to elucidate the temporal changes in textural and taste-related characteristics of seven super sweetcorn cultivars (viz., 'Bob 1', 'Bob 2', 'Bob 5', '7210', '6800', 'Primer Plus' and 'Conqueror') held at 3°C and under controlled atmosphere (CA) (8 kPa O 2 and 12 kPa CO 2 ) for 24 days. Maximum Load measured by the Kramer shear cell method, indicated that the changes in the texture of the cultivars followed different patterns during CA storage. Specifically, '6800' was ca. 1.3-fold firmer than the rest of the cultivars during the 24 days of storage. Dry matter as a proportion of fresh weight was also significantly different between cultivars and tended to decline after 3 days of storage, being 6% lower at the end of the storage period as compared to initial values. On a dry weight basis, total sugar content, was significantly different between cultivars and 1.2-fold greater at day 0 than at the end of the storage period. In particular, the concentration of total sugar on a dry weight basis was significantly higher in 'Bob 1', 'Bob 5' and 'Bob 6'. This said, when considering the results on a dry weight basis, the temporal changes in the sugar profile through storage were dependent on both genotype and storage duration.