The Effect of Freezing Raw Material on the Quality Changes and Safety of Salted Anchovies (Engraulis encrasicolus, Linnaeus, 1758) at Cold Storage Conditions

Abstract

This study demonstrates the effects of the freezing and frozen storage of anchovies prior to brining and dry-salting on quality changes and food safety during refrigerated storage (4 ± 1 °C). Fresh anchovies were divided into two groups, one of which was used as a control representing fresh raw material; the other was the experimental group and consisted of frozen and thawed anchovies stored at −18 °C for a year. Five different salt concentrations were used for brining (10, 15, 20, 25 and 30%) in addition to the dry-salting method. Microbiological, chemical, physical and sensory analyses were carried out during storage. Salt concentration and salting method had significant effects on the shelf-life of salted anchovy products, with the highest shelf-life corresponding to dry-salted anchovies (p < 0.05). The effect of using frozen and thawed raw materials for salting on the shelf-life depended on the processing method since the experimental dry-salted group had a shelf-life one month longer than that of the control group, while the opposite situation occurred for the brined samples, with one exception. Strong correlations were usually found between sensory values and chemical quality parameters (R2: 0.83–0.99 for the control group and 0.63–0.99 for the experimental group). The results demonstrated that the experimental group, with some exceptions, had better values for most quality and food safety parameters in comparison to the control group, indicating the advantage of using frozen and thawed raw materials before salting to prevent spoilage and enhance food safety. Considering that the experimental group was produced from one-year-stored raw material compared to the control group, the advantage of the freezing and frozen storage of anchovies can be accepted as much higher versus when freezing is not implemented. The positive effect is due to the fact that frozen anchovies absorb salt faster after thawing, especially in groups with high salt concentrations. Therefore, it can be concluded that frozen salted anchovies can be utilized for longer as they have a longer shelf-life, particularly when using either the 30% brining or dry-salting method.

Assessment of cooking methods and freezing on the nutritional value and health risks of heavy metals in four fish species consumed in Douala, Cameroon

“…Dama et al [ 22 ] showed that the protein content of Pseudotolithus typus decreased significantly (P < 0.05) after 21 days of freezing at −20 °C. During freezing, the formation of macrocrystals perforates cell membranes, promoting protein exudation and denaturation [ 47 ]. In the fresh fish, lipid content is higher significantly (P < 0.05) in E. fimbriata than in other species.…”