The Losses of Ascorbic Acid during the Large-scale Cooking of Green Vegetables by Different Methods

This work was undertaken to find out whether in large-scale cooking more ascorbic acid is retained when green vegetables are added in successive portions to boiling water than when they are added all at once in the traditional manner.The Accessory Food Factors Committee of the Medical Research Council (1941) referred to the destruction of ascorbic acid by oxidative enzymes present in raw vegetables.This action was said to be accelerated by increase in temperature until the enzymes are inactivated, which occurs within a few degrees of the boiling-point of water.In consequence, it was recommended that 'vegetables should be put in gradually or in small amounts at a time, so that the water does not go off the boil'.Gould, Tressler & King (1936) found that