Antilisterial Effect of a Natural Formulation Based on Citrus Extract in Ready-To-Eat Foods

Abstract

Controlling Listeria in food is a major challenge, especially because it can persist for years in food processing plants. The best option to control this pathogen is the implementation of effective cleaning and disinfection procedures that guarantee the safety and quality of the final products. In addition, consumer trends are changing, being more aware of the importance of food safety and demanding natural foods, minimally processed and free of chemical additives. For this reason, the current consumption model is focusing on the development of preservatives of natural origin, from plants or microorganisms. In sum, this study aimed to evaluate the antimicrobial effectiveness of a citrus extract formulation rich in flavonoids against several L. monocytogenes and L. innocua strains, using in vitro test (agar diffusion test, minimum bactericidal concentration (MBC), and time-kill curves) and challenge test in food trials (carne mechada, salami, fresh salmon, lettuce, brine, and mozzarella cheese). The results presented in this work show that citrus extract, at doses of 5 and 10%, had a relevant antimicrobial activity in vitro against the target strains tested. Besides this, citrus extract applied on the surface of food had a significant antilisterial activity, mainly in carne mechada and mozzarella cheese, with reductions of up to eight logarithmic units with respect to the control. These results suggest that citrus extract can be considered a promising tool to improve the hygienic quality of ready-to-eat foods.

In Vitro Toxicity Studies of Bioactive Organosulfur Compounds from Allium spp. with Potential Application in the Agri-Food Industry: A Review

“…The beneficial effects of OSCs compounds have been reviewed by different authors. In addition, their phytochemical profile has been well described [ 5 , 12 ]. However, as far as we know, the safety evaluation and toxicity effects of these compounds have not been reported.…”

“…The Allium spp. are also well known for their multiple biological effects, such as antiviral, antimicrobial, antioxidant, antiprotozoal, antidiabetic, anticarcinogenic, antispasmodic, antimutagenic, anti-amnesic, antiasthmatic, anti-inflammatory, neuroprotective, hepatoprotective, hypotensive, immunomodulatory, hypoglycemic, as well as their prebiotic properties [ 2 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ]. In relation to antibacterial activity, gram-positive bacteria seem to be more sensitive than gram-negative bacteria to these compounds.…”

A comparative analysis of traditional meat processing methods

“…Some researchers have observed the possible application of Debaryomyces hansenii as a probiotic, which is a native mushroom species usually used in sausage [21]. The quality of the sausage depends on different indicators, such as chemical composition, volatile flavour, and microbial arrangement [22]. Apart from their potential as starters or protective cultures in the food sector, salchichón and chorizo act as antimicrobial qualities of lactic acid bacterial strains obtained from Mediterranean dry-cured sausages [23].…”

Bioactivity of Essential Oils for Mitigation of Listeria monocytogenes Isolated from Fresh Retail Chicken Meat

“…Plant extracts have been proven to have wide antimicrobial efficacy toward foodborne pathogenic bacteria such as E. coli , Listeria innocua [ 14 ], and L. monocytogenes [ 15 , 16 ]. Natural food additives are commonly used, such as Proallium (garlic and onion extracts) [ 17 ] and Cycrom (20% citrus extract and organic acids) [ 18 ], which have already been commercialized. However, it is estimated that only 10% of the world’s 250,000–500,000 plant species have been assessed, and few studies have investigated the chemical composition and the mode of action of plant extracts [ 19 ].…”