EFFECT OF SMOKING TEMPERATURES ON ACCEPTABILITY AND STORAGE STABILITY OF SMOKED SPANISH MACKEREL

Abstract

The effect of temperature and smoking schedules on the quality of Spanish mackerel was evaluated using a pilot plant model of a commercial smokehouse system. Although the final moisture contents of the products are the same, the product smoked only at high temperature (160°F) had the softest texture. Smoking only at low temperature (100°F) did not develop surface color thus resulting in a product having the poorest appearance. A process which combined smoking at both low and high temperature at 60% RH gave a product having excellent texture and appearance. High temperature smoking above 160°F darkened the surface excessively and reduced product acceptability. A holding period after brining and between the cold and hot smoking stages in the process improved appearance and smoke flavor. Water phase salt content judged to be the optimum saltiness was 3.7%. Microbiological counts in the product of the combination cold and hot smoking process were very low (< 10/g). Smoking at 90–100°F did not allow an increase in surface microbiological count. The final step in the process when carried out at 160°F inactivated most of the vegetative microorganisms inoculated on the surface. Storage life of Spanish mackerel produced by cold followed by hot smoking (160°F) was 45 days at 38°F and at least 22 wk at 10°F. This process does not meet the 30 min at 180°F minimum temperature requirement in the Good Manufacturing Practice Regulation of the Food and Drug Administration for smoked fish; therefore, frozen storage and distribution are recommended.