Heating Regulation Of Liquid And Luncheon Meat Using Radio Frequency Heating

Traditional sterilizing method of pork luncheon meat could lead decrease of nutrition and sensory quality in the sense of long time heating. RF electromagnetic waves have high penetration depth, which may cause less heating time of food. This experiment researched the effects of factors on the liquid heating rate by RF heating, the factors include liquid’s height-diameter ratio, air height, liquid air ratio, electrical conductivity and electric fluid ratio of anode to grid. Computer vision system was developed for the determination of luncheon meat color. Pork luncheon meat heating and sterilizing process were developed using RF heating. The results were as follow:(1) When the air height and liquid air ration changes, the electric fluid ratio of anode to grid of three different height-diameter ration liqued firstly enlarge then diminish and possesses the maximum value. The lager the electric fluid ratio of anode to grid, the RF would heat the food quicker; the larger height-diameter ration, the quicker the heating. When the electrical conductivity of liquid is 900-1000 μs/cm, the electric fluid ratio of anode to grid is relatively large and the heating is also relatively fast. Which proves that the liquid height-diameter ration, air height, electric fluid ratio of anode to grid, electrical conductivity would seriously influence the heating speed.(2) The values investigated by computer vision system and color difference meter are highly relevant,and the results have no significant difference. The computer vision system designed in this research could investigate the L, a and b values of objects. And could replace the color difference meter’s investigating values.(3) In RF heating and high pressure vapor, the center of pork luncheon meat’s temperature raised to 80℃ would spent nearly twenty minutes. High pressure vapor assistant RF heating is dramatically faster than the other two aforementioned methods. And the RF heating is faster than the regular high pressure heating.(4) In RF heating and high pressure vapor assistant heating, after 10 minutes, L value gets the maximum, a value drop to the minimum. In high pressure vapor heating for 15 minutes, L value gets to maximum, a value drop to the minimum, as the heating time last, L value drop and the a value raise to stable. In RF heating and high pressure vapor heating, b value would diminish. And in the high pressure vapor assistant RF heating, after 10 minutes, the yellowness index achieves to its minimum, and will rise as the heating lasts. Sterilization effect heated by high pressure vapor assistant RF heating is better than RF heating, and high vapor heating individually.