Comparative physiology of field‐grown tomatoes during ripening on the plant or retarded ripening in controlled atmospheres

Abstract

Tomato fruits of six cultivars were harvested at three different stages of maturity or were harvested when mature-green and then stored in a modified gas atmosphere (2.5-4% 0,; 4% CO,) for 2 months. The fresh and stored fruits were analysed for their contents of sugars, organic acids and free amino acids, while proteins were separated by discontinuous electrophoresis on polyacrylamide gels. In general, the low molecular weight components decreased during storage. A comparison of mature-green fruits before and after storage showed that although total protein was not decreased, a different electrophoretic pattern was obtained following controlled atmosphere (CA) storage. Thus, although controlled atmosphere storage repressed the loss of chlorophyll and synthesis of lycopene, carotenoids and xanthophylls, the biochemical parameters measured showed a controlled change towards the conditions exemplified by ripe fruits. This was not so marked in some cultivars as it was in others. P . W .

Quality of Fungicide Treated and Individually Shrink‐Wrapped Tomatoes

“…The pyramid-shaped curves that were obtained are almost identical to those reported by Goodenough et al (1982). The monosaccharides are produced by polysaccharide degradation but are utilized as substrates for respiration (Goodenough and Thomas, 1980). Thus, their concentrations increase until all the storage carbohydrates are utilized, and then they decrease.…”

“…This is lower than the 2-3% sugar content that is characteristic of most tomatoes (Gould, 1974) but is partially due to the fact that tomato fruits that are harvested mature green tend to have lower sugar than those that are vine-ripened (Rick, 1978). In addition, tomato monosaccharides as low as 1.1% have been reported to occur even during normal ripening on the planet (Goodenough and Thomas, 1980). Several of the test groups showed a rapid rise in the fructose and glucose concentrations followed by a Pdpid decline.…”

Effect of sea water on biochemical properties of fruit of tomato (Lycopersicon esculentum Mill.) genotypes differing for ethylene production

“…4A) does not seem to be such a common response. During ripening, citrate has been reported to decline,4 to remain constant,31 or to increase32 confirming the pivotal role of genetic background and of growth conditions. Our cvs can be separated in two groups: one with normal ethylene production, WT, and the other with a reduced synthesis of ethylene or an insensitivity to ethylene, NOR and NR 28.…”

The Tomato Crop

“…Controlled atmospheres reduce the loss of chlorophyll and the synthesis of lycopene, carotenoids and xanthophylls (Goodenough and Thomas, 1980). If O2 concentration is reduced to 2% or lower increased off-flavours and uneven colour development will result.…”