EFFECT OF TROPICAL FRUIT JUICES IN THE PR ODUCTION OF MICROBIAL FISH SILAGE

Microbial Fish Silage was produced from under-utilized fish mixed with juice and waste fruits (pineapple and papaya) at 35-degrees-C. Six di fferent products were elaborated as following: A: fish muscle with pin eapple juice; B: fish muscle with fruit wastes; C: gutted fish with pi neapple juice; D: gutted fish with fruit wastes; E: whole fish with pi neapple juice; F: whole fish with fruit wastes. Process development wa s evaluated by measuring: pH, acidity, nonprotein nitrogen, consistenc y and exudate liquid. Results indicated a slow decrease in pH value an d production of acidity during 20 storage days. The addition of fruits to silage did not have any effect on these values. Silage liquefactio n or hydrolysis was related to the following parameters: consistency, non-protein nitrogen and exudate liquid. The addition of fruits was re lated to silage liquefaction or hydrolysis, and it was measured by the consistency. Exudate liquid and nonprotein nitrogen increased during storage time. However silage made from whole fish showed highest value s in those parameters than other processing conditions. This results s uggested that hydrolysis involve first enzymes from guts and second en zymes from muscle and head. Pineapple juice did not contribute to hydr olysis process. Mainly sensory, changes in the silage occurs during fi rst 24 hours and they were related to chemical changes. Proximal analy sis did not change during silage process and microbial counts indicate d the freshness of raw material used i this study.