The effectiveness of salt solution and vacuum packaging in extending the shelf life of cooked fish balls was evaluated. Freshly produced fish balls were bought and divided into five groups (one group was air packaged [control]; three groups immersed in salt solutions [2.5, 5.0, 10.0%]; one group, vacuum packaged) and stored at 4 ± 1C for 14 days. Changes in aerobic bacterial counts, pH, texture and sensory characteristics were evaluated and shelf life was determined based on bacterial counts and sensory evaluation. A microbiological shelf life extension of 6 days was obtained for vacuum packaged and 4 days for 10% salt-immersed fish balls compared with control's shelf life (<3 days). Based on sensory analysis, vacuum packaging and 2.5% salt-immersed fish balls extended the shelf life of fish balls by 6 days compared with control's shelf life (<9 days). There was no significant (P > 0.05) changes in the pH values for treated fish ball samples.
PRACTICAL APPLICATIONSA limited shelf life of 4-5 days at 5C and 2 days without refrigeration is one of the major problems faced by the chilled fish ball industry especially the small-to medium-scale industries. Limited shelf life is also a problem to the consumers. As a product with high water content and rich in protein, fish balls are prone to the growth of microorganisms especially if stored at room temperature as what is commonly practiced at retail. Although freezing the fish balls enables them to last longer, the consumers and retailers might not prefer that as it tends to affect the texture and freshness of the fish ball. Thus, the development of readily available, inexpensive, simple and practical treatments to extend the shelf life of chilled fish ball at home and retail is much needed.