Effect of Goraka Concentrate in Curing Mixture on the Quality of Traditional Fermented Fish (Jaadi)
P.S. JAYASINGHE, T.S.G. FONSEKA and A. BAMUNUARACHCHI
Jaadi is a tropical fermented fish product commonly used to preserve fish during peak seasons. Goraka (Garcinia camboges) is an acidic fruit added to give a low pH. Studies have shown that the ideal curing mixture should have salt: fish in 1:3 ratio. This study was carried out to establish ideal concentration of goraka in curing mixture.
Jaadi was made in the laboratory using Sardinella longiceps species by altering the concentration of goraka while keeping 1:3 salt fish ratio. The ratio of weight of fish:weight of goraka used in the four different treatments were 6:1. 10:1. 12:1 and 15:1. The acceptability and shelf life of different treatments were evaluated using chemical and microbiological analyses. Organoleptic tests were carried out by a trained taste panel. The chemical parameters tested were total volatile nitrogen (INN), trymethylamine (TMA), oil and free fatty acid (FFA) contents, peroxide value, pH and dry matter content. Total bacterial counts (TBC) of the samples were also determined. The samples were assessed at monthly intervals for six months.
The TBC decreased during the fermentation period when fish:goraka ratios were 6:1 and 10:1. The pH, oil content, and peroxide value also decreased during the fermentation period. The highest decrease in pH was observed when fish:goraka ratio was 6:1. The dry matter content and TVN increased during the fermentation period. The overall acceptability of the product was higher when fish:goraka ratios were 6:1 and 10:1. Since there is no significant difference in the quality and overall acceptability when fish:goraka ratios are 6:1 and 10:1, considering the cost of preparation, it appears that 10:1 fish:goraka ratio would be the ideal treatment.