Inhibition of Browning and Ethylene Production in Shredded Cabbage by Isothiocyanates

Abstract

In recent years, there has been a rapid increase in the demand for shredded vegetables. Optimum techniques for preserving such vegetables, however, have not yet been established.
Browning is a major problem for the preservation of shredded cabbage. The study was attempted to find an effective way to prevent it from browning.
1. Differences in browning, ethylene production and allyl isothiocyanate (AITC) concentration in shredded cabbage were investigated among 10 cultivars of cabbages. Cultivars‘Ginryoku’and‘Shikidori’showing a slight browning (less than 4 in ΔE(Lab)) 24 hours after shredding, produced a small amount of ethylene (less than 0.9nl•g^-1•h^-1) and contained a large amount of AITC (more than 3mg•100g^-1 F. W.). In contrast, ‘Akimakichuwase 2’, ‘Shin A go’, ‘Shutoku’, ‘Derishasu’, ‘Shinkashu’, ‘Kandori 1’, ‘Shuki’and‘Koshinohikari’showed an intense browning (more than 9 in ΔE(Lab)), produced a large amount of ethylene (more than 2.3nl•g^-1•h^-1) and contained a small amount of AITC (less than 1.2mg•100g^-1 F.W.).
2. Exogenously supplied AITC inhibited browning, ethylene production and respiration in shredded cabbage.
3. Isothiocyanates, such as ethyl, butyl, phenyl, benzyl, and cyclohexyl isothiocyanates, were found to have the same effects as allyl isothiocyanate on inhibition of browning, ethylene production and respiration, except that cyclohexyl isothiocyanate did not inhibit browning.