Consumers and food processors alike face a global problem in ensuring that food is safe for consumption and will not hurt when prepared according to its intended purpose. In Malawi, the only cost-effective fish preservation methods are chilling, icing, and refrigeration which are unfortunately hampered by the intermittent power supply. This study explored the preservation of fresh tilapia fish in Lactobacillus paracasei spp. paracasei 3 and Lactococcus lactis spp. lactis 1 culture under temperature conditions used during distribution towards the improvement of freshness quality. Data collection and analysis was conducted between October and December 2020 and the results revealed that Lactococcus lactis spp. lactis 1 strain effectively inhibited the growth of fish pathogens in both storage temperatures compared to Lactobacillus paracasei spp. paracasei. The Total Viable Counts (TVC) of the treated samples were decreasing from 5 log10 CFU/g to 2 log10 CFU/g and increasing untreated samples from 5 log10 CFU/g to 8 log10 CFU/g after 24 hours of storage, respectively. A very stronger inhibition (38.33 mm) and strong inhibition (18.67 mm) was produced by Lactococcus lactis spp. lactis 1 against Staphylococcus aureus and Aeromonas hydrophila pathogens, respectively. Conversely, a very strong inhibition (27 mm) was also achieved by Lactobacillus paracasei spp. paracasei 3 against Streptococcus pyrogen fish pathogen. The lowest concentration (0.35 mg MDA/Kg) of Thiobarbituric Acid Reactive Substance (TBARS) was achieved in treated samples after 24 hours of storage at ambient and refrigeration storage, respectively. However, the untreated samples became rancid after exceeding the acceptable limit of 2.5 mg MDA/Kg in both storage conditions after 24 hours of storage. The effect of Lactic Acid Bacteria (LAB) culture was manifested after 12 and 18 hours of ambient and refrigeration temperatures and extended the shelf life of fresh tilapia from 12–15 hours and 18–27 hours at ambient and refrigeration storage, respectively. In conclusion, the use of lactic acid bacteria culture as a bio preservative method can maintain the freshness quality of the fish during distribution to the outlets when adopted and utilized by fish farmers and fish itinerant traders.
Published Date: 2022-06-20; Received Date: 2022-04-11