Changes in quality of rainbow trout (Oncorhynchus mykiss) fillets preserved with salt and sugar at low concentrations and stored at 4°C

Development of a Multifunctional Edible Coating and Its Preservation Effect on Sturgeon (Acipenser baeri♀× Acipenser schrenckii♂) Fillets during Refrigerated Storage at 4 °C

Although many coatings and films can improve the quality and shelf life of fish fillets during refrigerated storage, a more multifunctional coating material is needed. In this study, an edible alginate/protein-based coating solution was prepared by incorporating antimicrobial agents. The coating properties were characterized and its effects on the quality and shelf life of sturgeon fillets during refrigeration (4 °C) were investigated. Compared with sodium alginate coating (2% sodium alginate + antibacterial agents, H), the composite coatings (2% sodium alginate + antibacterial agents + 1:15 or 1:10 protein solution, HP-15 and HP-10) exhibited a more stable structure and better light, gas, and water barrier properties, and showed better quality-preservation effects on sturgeon fillets. The composite coatings treatments, especially HP-10 composite coating, exhibited significant (p < 0.05) effects in inhibiting microbial growth, maintaining sensory quality, reducing the production of total volatile basic nitrogen (TVB-N), decreasing nucleotide breakdown, and delaying the lipid oxidation and protein degradation in fillets. These findings confirm that the composite coatings can be used as a multifunctional coating material for freshness preservation of sturgeon fillets to improve quality and extend shelf life.

Biogenic amines levels in food processing: Efforts for their control in foodstuffs

Fermented and/or protein-rich foods, the most widely consumed worldwide, are the most susceptible to the presence of high levels of biogenic amines (BAs). Many reviews have focused on BAs toxicity and presence in foods; however, technological strategies such as evaluation of physical parameters, the addition of natural or synthetic compounds or the use of specific starter cultures of BAs reduction, and quick detection methods have been scarcely approached. In current research, there has been a focus on fast detection of BAs through colorimetric methods that allow these compounds to be quickly and easily identified by consumers. To reduce BAs presence in food, several alternatives have been developed and investigated with the aim of preventing negative effects caused by their intake, which can be applied before, during, or after processing. Food safety is one of the most important concerns of consumer and sanitary authorities. Therefore, detecting toxins such as BAs in food has become a priority for research. Recent reports that focus on the development of rapid detection methods of BAs are reviewed in this analysis. These methods have been successfully applied to food matrices with little to no sample pretreatment. Several alternatives for BAs reduction in food was also summarized. These findings will help the food industry to improve its processes for developing safe food.

Nucleotide degradation, biogenic amine level and microbial contamination as quality indicators of cold-stored rainbow trout (Oncorhynchus mykiss) gravad

The extent to which the transformation of nucleotides, biogenic amines, and microbiological changes affect the quality and shelf life of vacuum packaged low processed rainbow trout (Oncorhynchus mykiss) gravad during storage at 7 ± 1 °C for 42 days was investigated. Although total viable counts increased slowly up to 6 log CFU g^-1 at the end of storage, coliform bacteria disappeared. The histamine concentration and the biogenic amine index increased up to 45.2 ± 1.62 mg kg^-1 and 100 mg kg^-1 respectively. The highest concentration of inosine monophosphate was achieved in freshly prepared gravad, whereas the hypoxanthine level increased with storage time up to 28 days. Among nucleotide ratios, the G value is more suitable for the determination of gravad quality than K, K_i and H values. Once the gravad obtained the limit of acceptability by the panelists (35 days) the G value rose to 470%.