| Enzymatic browning of tubers owing to mechanical injury is assessed to indicate bad quality, mainly for visual reasons. Browning is also a serious problem during processing of potatoes. The effect of farmyard manure and mineral fertilization at three levels (50, 100, 150 kg total N per hectare) on darkening of potato extract was investigated in three years in a field trial. The extinction of the extract was measured at 400 nm for two days at three dates during the storage period from autumn to spring. The extract of organically fertilized tubers hat a lower extinction compared to the mineral treatments. This difference occurred right at the beginning of the test with the fresh extract as well as during the following two days, when darkening continued... |
