Effect of salt concentrations and drying methods on the quality and formation of histamine in dried milkfish (Chanos chanos)

The effects of salt concentrations (0–15.0%) and drying methods on the quality of dried milkfish were studied. The results showed that the levels of aerobic plate counts, total coliform, water activity, moisture contents, total volatile basic nitrogen (TVBN) and thiobarbituric acid (TBA) of the dried milkfish samples prepared with the same drying method decreased with increased salt concentrations. The samples prepared with the cold-air drying method had better quality in term of lower TVBN and TBA values than those of samples prepared with other drying methods. The histamine contents in all samples, except two, prepared with various salt concentrations by different drying methods were less than 1.9 mg/100 g. Two unsalted samples prepared with hot-air drying at 35 °C and sun drying methods were found to contain histamine at levels of 249.7 and 67.4 mg/100 g, respectively, which were higher than the potential hazard level of 50 mg/100 g.

► Cold-air drying milkfish had better hygienic quality than other drying methods.
► Histamine (>50 mg/100 g) in unsalted samples by hot-drying at 35 °C and sun drying.
► Low histamine contents observed in salted samples (>2.5% NaCl) by drying methods.