Some Physicochemical Characteristics of Fish Products Sampled from Bulgarian Retail Markets

The quality and safety of fish products is determined by chemical, physical, and microbiological parameters, important for satisfying consumers’ requirements. Also, the freshness of fish is essential for evaluation of its quality. On the Bulgarian retail market, fish is commonly offered chilled, frozen, or processed. The purpose of this study was to determine some physicochemical characteristics of fish products sampled from Bulgarian retail markets.
During June to July 2017, this survey was performed on 45 samples from smoked, semi-dried, marinated, and frozen fish products sold in Bulgarian markets. The samples were collected from specialized stores for fish products, and transported to the laboratory for analysis. Water content, water activity (aw), pH, salt content, and ash content were determined according to the standard protocols.
The highest average water content was established in frozen products, followed by almost equal values in marinated, smoked, and semi-dried fish products. The average aw value was also the highest in frozen products (0.975), it was almost the same in marinated and smoked (0.892); and the least in semi-dried fish products (0.905). Semi-dried (3.36%), marinated (3.19%), and smoked (3.03%) fish products had considerably higher average salt content than frozen ones (0.1%). The average pH value of marinated fish products (5.26) was lower than frozen (6.88), smoked (6.76), and also semi-dried (6.68) ones. Average ash content was substantially higher in smoked (7.16%), semi-dried (6.57%), and marinated (5.97%) fish products compared with frozen products (1.18%).
It is concluded that the frozen fish products sold in Bulgarian markets are probably more susceptible to spoilage than marinated, smoked, and semi-dried ones.