METHOD FOR REMOVING ASTRINGENCY AND AFTERRIPENING UNRIPE BANANA AND APPARATUS THEREFOR

PURPOSE:To carry out economically the removal of astringency and prolong the shelf life at the shop front, by continuously carrying out the vacuum treatment of unripe bananas and the subsequent permeation treatment with a removing agent for the astringency thereof continuously. CONSTITUTION:Unripe bananas are introduced into a treating chamber 1, which is then closed. A vacuum pump 6 is driven to keep the interior of the treating chamber 1 at a negative pressure corresponding to the ripeness of the bananas to deaerate the interior of the flesh of the bananas moderately and evaporate the moisture. The maximal negative pressure in the deaerating treatment is kept for a given time. Opening and closing regulating valves 5 are opend to blow a removing agent for the astringency, e.g. an alcohol type, in a tank 4 from jetting nozzles 2 into the treating chamber 1 to permeate fully the removing agnet for the astringency fully into the interior of the flesh. The treated bananas are then taken out of the treating chamber 1 and then kept at a suitable temperature in the treating chamber 1 or on the outside of the treating chamber 1 to afterripen the bananas. As a result, the removing treatment of the astringency can be economically carried out, and the shelf life at the shop front can be prolonged at the same time.