How Cumin Seed Oil Can Help Keep Meatballs Fresh Longer

The study focused on encapsulating CEO to improve its stability and effectiveness. Encapsulation involves trapping the CEO within a protective matrix, in this case, CPI and MD, which helps in maintaining the oil’s integrity and controlled release. The surface morphology results showed successful dispersion of CEO in the wall material matrix, confirmed by specific peaks in the FT-IR spectra of encapsulated and non-encapsulated CEO.

The antimicrobial activity of non-encapsulated CEO was initially evaluated against several bacterial strains, including Escherichia coli BC1402, Pseudomonas aeruginosa ATCC 27853, Salmonella Typhimurium ATCC 0402, and Staphylococcus aureus ATCC 25923, using the disc diffusion assay. Among these, P. aeruginosa ATCC 27853 and S. Typhimurium ATCC 0402 were more sensitive, with inhibition zones ranging from 11.20 to 12.66 mm. The lowest minimum inhibitory concentration (MIC) was noted for non-encapsulated CEO against P. aeruginosa ATCC 27853 (0.5 mg/mL), while the highest minimum bactericidal concentration (MBC) was found for encapsulated CEO against S. aureus ATCC 25923 (16 mg/mL).

The findings align with previous research that highlighted the antimicrobial properties of CEO. For instance, a study demonstrated that CEO, primarily composed of cuminal, disrupted the membrane integrity of E. coli and Listeria innocua, increasing cell permeability^[2]. This mechanism contributes to the oil’s effectiveness in inhibiting bacterial growth. Additionally, the antioxidant properties of CEO, due to its high total phenol content, further enhance its preservative potential^[2].

Encapsulation of CEO in a CPI-MD matrix also builds upon earlier findings where CPI-MD was used to stabilize cumin seed oil emulsions. The encapsulation process improved the retention and efficiency of the oil, with significant benefits observed in the microcapsule properties^[3]. This technique ensures that the volatile compounds of CEO, such as cymene, α-pinene, and cumin aldehyde, remain intact during processing, which is crucial for its antimicrobial activity.

The study also evaluated the in situ antibacterial activity of encapsulated CEO in meatballs, comparing it to nitrite, a common synthetic preservative. The microbial load of meatballs without any additives increased significantly over 14 days of storage at 4°C, while those treated with CEO showed notable inhibition of microbial growth. The encapsulated and non-encapsulated CEO demonstrated statistically significant differences from nitrite in reducing total aerobic mesophilic and coliform counts, highlighting its potential as a natural preservative.

Interestingly, the interaction of CEO with bacterial strains, particularly E. coli, has been explored in other studies. For example, the combination of monoterpenes like α-pinene with antibiotics showed enhanced antibacterial effects, suggesting that CEO components could similarly potentiate the effectiveness of other antimicrobial agents^[4]. This synergy could be vital in developing new preservation strategies for food products.

In conclusion, the encapsulation of CEO in a CPI-MD matrix by spray drying not only preserves its antimicrobial properties but also enhances its application in meat-based products as a natural preservative. This study from Istanbul Technical University paves the way for future research on natural alternatives to synthetic preservatives, addressing the growing issue of antibiotic resistance and the demand for cleaner food labels.