Improvement of Fermented Fish Flour Quality Using Essential Oil Extracted From Fresh Leaves of Pimenta racemosa (Mill.) J. W. Moore

Effect of West Indian Bay Leaf (Pimenta racemosa) and Turmeric (Curcuma longa) Essential Oils on Preserving Raw Chicken Breasts

Research background

While the use of chemical preservatives in meat may appear to be tremendously advantageous, they have long been purported to increase the risk of incidence of certain types of cancers. Consequently, many people have opted for minimally processed alternatives. This consumer shift has placed substantial pressure on the food industry to implement more natural alternatives to these synthetic preservatives in the meat industry. Research on plant extracts as potential agents for food additives is increasing. The bioactive components present in West Indian bay leaf and turmeric essential oils have a promising potential for use as novel, green preservatives in the meat industry.

Experimental approach

Raw chicken breast samples (28 g) were each treated with different volumes (0.5, 1 and 1.5 mL) of the essential oil of West Indian bay leaf or turmeric or their mixture (1:1 to make up a final volume of 0.5, 1 and 1.5 mL). Physicochemical, microbiological and sensory evaluations were performed on the fresh and treated samples stored for 14 days at 4 °C.

Results and conclusions

The West Indian bay leaf oil had a higher extraction yield and total phenolic content, while the turmeric oil had a higher total flavonoid content. The most effective treatments, compared to the control, significantly (p<0.05) minimized the pH increase by 13.9 % (1.5 mL bay leaf oil), reduced texture loss by 44.8 % (1.5 mL oil mixture) and reduced protein loss by 98.9 % (1 mL bay leaf oil). Most treated samples had reduced microbial loads, with the turmeric oil showing the highest efficacy against lactic acid bacteria, yeasts and moulds. Treated samples had significantly higher (p<0.05) sensory scores than the control on the final day of storage, with the 1.5 mL oil mixture proving to be the most effective, as the storage life of the chicken breast sample was extended by 6 days.

Novelty and scientific contribution

This study has shown for the first time that the essential oil from turmeric and West Indian bay leaf can extend the shelf life of raw chicken breast and highlights the potential of the oil as natural preservative agents in lieu of synthetic alternatives.

Antimicrobial ingredients of Zanthoxylum motuoense and potential in fresh pork meat preservation

Zanthoxylum motuoense (Tibetan prickly ash, MTHJ), different from the Chinese prickly ash species, is distributed only in the Tibet. Now the chemical characterization and antibacterial activity of MTHJ extracts were analyzed for the first time. As a result, Schinifoline (12), γ-Fagarine (8), (2E,7E,9E)-6 S-Hydroxy-N-(2-methylpropyl)-11-oxo-2, 7, 9-Dodecatrienamide (6), and Neoechinulin A (17) were found to be the major different factors by untarget LC-MS metabolomics together with quantitative analysis on target. These four compounds were also the major antibacterial constituents. Then, the antimicrobial activity of MTHJ fractions was evaluated with colony forming units (CFU), fluorescence microscopy imaging, SEM and investigating the potential food preservation. Nutritional composition, colour and sensory evaluation of extract-treated samples were evaluated along storage time. The results suggested the MTHJ may be used for meat products preservation, and the scores were significantly higher for its unique flavor, which offered a promising choice for food safety, preservation and reducing foodborne illness.