Internal temperature Visual Observation

Proceeding of 2013 International Seminar on Climate Change and Food Security ISCCFS 2013 Palembang, South Sumatra -Indonesia, 24-25 October,2013 166 Fig. 2: Effects of microwave oven heating time on the number of microbes in pepes

4.2. Internal temperature

The measurements of pepes internal temperature showed that all treatments exceeded the minimum standard of internal temperature of 63 °C. The average internal temperature pepes are 73.8 °C of A 1 treatment cooking for 4 minutes, 76.1 °C of A 2 cooking for 5 minutes and 81.7 ° C of A 3 cooking for 6 minutes Figure 3. Increasing cooking time caused increase in pepes internal temperature. Similar result has been reported for cooked meat by microwave oven [19] . Fig. 3: Internal temperature of pepes processed by microwave oven Cooking could increase pepes internal temperature due to heat transfer from heat source. There are three modes of heat transfer, which contribute to the overall heat transfer process in differing proportions namely conduction, convection and radiation. Conduction is the transfer of heat by molecular motion in solid bodies. Convection is the transfer of heat by fluid flow, created by density differences and buoyancy effects, in fluid products. Radiation is the transfer of electromagnetic energy between two bodies at different temperatures [24] .

4.3. Visual Observation

Visually, pepes from A 1 treatment cooking time of 4 minutes produced rare state of pepes . This was shown by clear, reddish flesh, a transparent fat in the abdominal area and in the abdominal cavity, moist and chewy texture of flesh, flesh was attached to bone and moist texture of spices. Both A 2 cooking for 5 minutes and A 3 treatments cooking for 6 minutes produced a well done state of pepes and shown by typical brownish white-coloured flesh, white fat in the abdominal area and in the abdominal cavity, moist and tender texture of flesh and spices, and flesh was easily removed from bone. Fish heating converts the translucent, jelly-like cellular mass into an opaque, friable, slightly firm and springy form. Synaeresis or shrinkage occurs and fluid is release, the proteins in which may coagulate to Proceeding of 2013 International Seminar on Climate Change and Food Security ISCCFS 2013 Palembang, South Sumatra -Indonesia, 24-25 October,2013 167 form curd separately from the main solid mass. As noted above, the connective tissue holding the cells together is easily degraded and blocks of cells or the cells themselves become readily separated from one another. Thus, unlikely many meats, cooked fish easily falls apart and becomes palatable on mild heating [25] .

5. Conclusion