View related articles View Crossmark data Citing articles: 2 View citing articles Effects of bay leaf (Laurus nobilis) and green tea (Camellia sinensis) extracts on the physicochemical properties of the marinated anchovies with vacuum packaging

Marinated anchovies produced in a fish processing plant in Samsun province (with 3% garlic and 3% hot pepper sauce) were filled in plastic jars and vacuum packed. Physical, chemical and microbiological analyses of the samples were performed to determine the effects of garlic and hot pepper sauce on the shelf life of marinated anchovies. Total viable bacteria count (TVB), lactic acid bacteria count (LAB), Enterobacteriaceae count, biogenic amines (histamine, tyramine, cadaverine, putrescine, tryptamine), pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid (TBA) analysis were performed during 7 months of storage at 4°C. Comparing the control group with garlic added and hot pepper sauce added samples, garlic addition reduced the microbial growth and provided that the samples retained their physicochemical properties (TBA, TVB-N) for a longer period time. The amounts of biogenic amines were determined less in garlic added samples.

Hot-smoked rainbow trout (Oncorhynchus mykiss) fillets with vacuum packaging are an important export source and the manufacturers recommend a shelf life of 21 d at 4 °C. This time is very short in terms of the shelf life of packaged foods. In this study, nisin and lysozyme (0.5 and 1% w/v, respectively) were used in order to prolong the shelf life of hot-smoked rainbow trout by adding them to the brine (8–10 ˚C, 10 h). Five treatment groups were formed, including the control group. Samples (105) were hot-smoked at 72 ˚C and vacuum-packaged. The effect of nisin and lysozyme (0.5 and 1% w/v) on the chemical [(pH, total volatile basic nitrogen (TVB-N), peroxide, thiobarbituric acid reactive substances (TBARS), free fatty acids (FFAs)], microbiological [total number of aerobic mesophilic bacteria (TMAB), number of lactic acid bacteria (LAB), total number of coliform bacteria (TCB), total number of psychrophilic bacteria (TPB)], and sensorial properties were investigated during storage at 4 °C for 42 d. TVB-N, TBARS, and FFA values were evaluated. The most favorable results among the treatment groups for the chemical analysis were observed in groups treated with nisin (1 and 0.5%, respectively) followed by lysozyme-treated groups (1 and 0.5%, respectively), and the control group. Nisin and lysozyme showed the most important effect microbiologically and extended the shelf life of the samples from 21 d to 42 d at 4-˚C storage. The sensory analyses suggested that nisin and lysozyme treatments did not have a negative impact on the organoleptic properties of samples. Natural antimicrobials (nisin and lysozyme) reduced the TMAB, TCB, and TPB. As a result, it was determined that nisin and lysozyme can be used to increase the quality characteristics and shelf life of hot-smoked rainbow trout fillets instead of synthetic antioxidants and additives.