EFFECT OF ROTATION ON PROCESS TIME OF THERMALLY PROCESSED MACKEREL IN OIL IN ALUMINUM CANS

Abstract

ABSTRACT This study was conducted to standardize the optimum processing condition for thermal processing of mackerel in refined groundnut oil in aluminum cans. The standardization of the product was carried out in still retort at 121.1C at three different Fo (accumulated lethality) values, i.e., 5, 7 and 9. The total process times required to reach the Fovalues 5, 7 and 9 were 34.06, 41.29 and 45.09 min, respectively. The Fo9 was selected for further rotation studies based on sensory analysis and sterility test. Rotation was carried out at 2, 4 and 6 rpm and resulted in the reduction in the process time to 42.08, 41.38 and 38.22 min, respectively, for the same lethality compared to 45.09 min in stationary retort. The cook value also reduced with increase in the rotational speed.PRACTICAL APPLICATIONSThe present work was carried out to standardize the optimum thermal processing parameters for mackerel in oil medium in aluminum cans and to study the effect of rotation on process time. The standardization of process parameters will help the processors to directly implement in commercial retort operation. The longer duration of thermal processing leads to the deterioration of product quality. Reductions in process time will have an advantageous effect on the sensory and nutritional qualities of thermally processed fish products. The reduction of process time can be achieved by rotating the content of canned product during processing. In rotational study, it has been observed that the total process time could be reduced to 6 min compared to the stationary retort sterilization process at a given temperature and Fo value. This will help the processes to minimize the energy consumption for thermal processing and to produce better quality products.