The Essential Oil of Tunisian Halophyte Lobularia maritima: A Natural Food Preservative Agent of Ground Beef Meat

Abstract

This study was directed towards the investigation of the chemical composition and antimicrobial properties of the essential oil of Tunisian halophyte Lobularia maritime (LmEO). The antibacterial effects against major food-borne pathogenic and food spoilage bacteria were tested using the well diffusion method, followed by the determination of the minimum inhibitory (MIC) and bactericidal (MBC) concentrations. The essential oil has shown strong antimicrobial activity against eight pathogenic strains, which was attributed mostly to predominant constituents of the essential oil: benzyl alcohol, linalool, terpien-4-ol and globulol, as well as to synergistic effects of its major and minor constituents. Considering strong antimicrobial effects of the tested essential oil, it was further tested as a natural alternative to food preservatives, using minced beef meat as a model system. Minced beef meat was spiked with 0.019, 0.038, and 0.076% of the essential oil and stored during 14 days at 4 °C, monitoring its microbiological, physicochemical, and sensory properties. Chemical analyses revealed that meat treated with 0.076% of LmEO at underwent a significant decrease (p < 0.05) in primary and secondary lipid oxidation and reduced metmyoglobin accumulation compared with control samples. Furthermore, microflora proliferation in the meat model system spiked with 0.076% of LmEO was significantly (p < 0.05) reduced in comparison to control. In addition, two multivariate exploratory techniques, namely principal component analysis (PCA) and hierarchical analysis (HCA), were applied to the obtained data sets to describe the relationship between the main characteristics of the meat samples with and without essential oil addition. The chemometric approach highlighted the relationships between meat quality parameters. Overall, results indicated that the essential oil of Lobularia maritima deserves to be considered as a natural preservative in the meat industry.

A New Approach in Meat Bio-Preservation through the Incorporation of a Heteropolysaccharide Isolated from Lobularia maritima L.

“…On the seventh day of cold storage at 4 °C, APC levels did not exceed 4 log 10 CFU/g in the meat samples treated with Lm PS and BHT. The logarithmic evolution of APC in samples treated with different concentrations of Lm PS was suppressed and did not overcome the maximum recommended limit (6.7 log 10 CFU/g) [ 6 ], even on day 14 of storage. Therefore, treatment with Lm PS at 0.6 % ( v/w ) protected minced meat from APC contamination, thus extending its shelf life.…”

“…The impact of Lm PS was related to dosage and storage duration. Ben Akacha et al [ 6 ] reported that the treatment of minced beef meat with the essential oil of L. maritima at a rate of 0.076% resulted in high antimicrobial activities against APC, PTC and Enterobacteriaceae .…”

“…Such data resulted in lipid oxidation, browning reactions caused by non-enzymatic processes, and myoglobin oxidation, which are considered the main factors influencing meat colour [ 55 ]. Ben Akacha et al [ 6 ] related sensory properties to microbiological investigations. The high levels of microorganisms and lipid oxidation caused unsatisfactory sensory properties of the untreated meat.…”

“…due to their possible cytotoxic and carcinogenic effects [ 3 , 4 ]. This prompts the food industry to search for natural antioxidant preservatives [ 5 , 6 ]. Plants may be a main source of natural antioxidants since nearly all plants contain antioxidants that play a role in protecting against solar radiation and pests, as well as regulating chemical energy production [ 7 ].…”

Biopreservative Effect of the Tunisian Halophyte Lobularia maritima Flavonoid Fraction, Used Alone and in Combination with Linalool in Stored Minced Beef Meat

“…The determination of the minimum inhibitory concentrations (MICs) of Lm FV and Lin was based on the method previously reported by Ben akacha et al [ 29 ]. In brief, the evaluation was performed using the broth microdilution method (96 microplates) with the addition of 10 µL of cell suspension and incubation overnight at 37 °C.…”