Evolution of amylase activity in tuberous-rooted chervil (Chaerophyllum bulbosum L.) roots during storage at various temperatures

The storage of tuberous-rooted chervil (Chaerophyllum bulbosum L.) roots after harvest is necessary for the gustative qualities to develop via starch hydrolysis. This process can take several months before roots can be marketed. Exposure to low temperature accelerates the degradation process of starch, and therefore shortens the storage time. In order to explain the degradation of starch at low temperature, the enzymatic activities of amylase in roots stored at 4, 10 or 16°C have been studied. A higher activity of beta-amylase at 4°C than at 10 or 16°C and conversely a higher activity of alpha-amylase at 16°C were observed. The activity of beta-amylase increased immediately after the beginning of storage, while alpha-amylase activity increased later. The activity of beta-amylase was overall higher than alpha-amylase activity. These results suggest that beta-amylase activity in tuberous-rooted chervil roots is induced by low temperature and is responsible for the observed early starch hydrolysis. These findings are important for the optimization of storage conditions in relation to the management of marketing this new crop.