Development and Performance Evaluation of an Automatic Vacuum Packer of the Continuous Type

The objectives of this study were to develop an automatic vacuum packer of continuous type and to evaluate its performance for packing white rice with embryo. The vacuum packer consisted of a pressing board assembly, a vibrating conveyor assembly, a tape adhering assembly, and a gas filling system. The processing capacity of the vacuum packer was 6 pouch min−1. The success rate of the vacuum packaging of the machine was 92·6%. The changes of the whiteness, moisture content, peroxide value, and acid value of non-vacuum-packed and vacuum-packed samples were investigated to analyse the preservation effects of vacuum packaging on rice quality during the storage of 3 months. The results obtained from the storage experiment were as follows: (1) the whiteness of the non-vacuum-packed and vacuum-packed rice decreased by 4 and 2, respectively; (2) the moisture content of the non-vacuum-packed and vacuum-packed rice decreased by 1·3 and 0·8% (w.b.), respectively; (3) the peroxide value of the non-vacuum-packed rice increased by 3·45 meq kg−1 and then dropped moderately; but the value of the vacuum-packed samples increased by 1·89 meq kg−1; (4) the acid values of the non-vacuum-packed and vacuum-packed rice increased by 0·98 and 0·71 mg g,−1 respectively; (5) The vacuum packaging suffocated all the insects in the pouches.