Table 1.

Overview of studies testing the efficacy of essential oils and plant extracts or their components when added to meat products.

Anti-Microbial Agent—Concentration Applied	Food Product	Microorganisms Targeted	Indicative Reduction (Log10 CFU/g, Log10 CFU/mL, Log10 CFU/cm2) 1,2,3,4	Reference
Bay—0.5% v/w	Ground chicken	Total viable counts	0.14–0.47	[35]
		Listeria monocytogenes	0.07–0.36
		Escherichia coli	0.12–1.22
Cinnamon—1% w/w	Marinade on chicken	Lactic acid bacteria	0.5	[36]
		Yeasts and moulds	0.8
		E. coli	0
		Coliforms	0
1% w/w	Marinade on pork	Lactic acid bacteria	0	[36]
		Yeasts and moulds	2.4
		E. coli	0
		Coliforms	0
Clove—0.5%, 1%	Minced beef	Aspergillus flavus	2.42–3.01 5	[37]
Coriander—0.02% v/w	Ground beef	Total viable counts	0.1–0.4	[38]
		Enterobacteriaceae	1–1.5
		Lactic acid bacteria,	0–0.8
		Total anaerobic counts	0.5
Fennel—0.2% v/w	Chicken	Total viable counts	0.9	[39]
		Enterobacteriaceae	2.4
		Lactic acid bacteria	0
Garlic—0.5%, 1%	Minced beef	A. flavus	1.93–2.12 5	[37]
Ginger—3%, 6% w/w	Chicken	Psychrophilic bacteria	2.7–4.5 6	[40]
		Yeasts and moulds	0.9–3.3 6
Hop—5000 ppm	Model marinade on pork	Mesophilic bacteria	0.9	[41]
		Enterobacteriaceae	0
		Listeria monocytogenes	1.5
		Lactic acid bacteria	1.3
Hyssop—0.02% v/w	Ground beef	Total viable counts	0–0.3	[38]
		Enterobacteriaceae	0.9–1
		Lactic acid bacteria	0.1
		Total anaerobic counts	0.5
Nutmeg—10, 20 ppm	Cooked Sausage	Total mesophilic bacteria	0.13–0.38 7	[42]
Oregano—0.3%, 0.4%, 0.5% v/w	Chicken	Salmonella sp.	2.7–3.8	[43]
0.2% w/w	Chicken	Lactic acid bacteria	0.67–0.86	[44]
Pepper—0.1%, 0.5% v/v	Pork	Pseudomonas spp.	2.1–3.05	[45]
		Enterobacteriaceae	1.05–1.85
		Brochothrix spp.	0
		Lactic acid bacteria	0
Peppermint—0.25%, 0.5% v/w	Minced beef	Total aerobic bacteria	1.44–1.58	[46]
		Psychrotrophic bacteria	1.36–1.4
		Enterobacteriaceae	0.3–1.2
		Pseudomonas spp.	1–1.11
Rosemary—2% v/w	Chicken	Pseudomonas aeruginosa	0	[47]
		Lactic acid bacteria	2.57
0.2% v/w	Chicken	Anaerobic bacteria	1.05	[48]
		Enterobacteriaceae	3.62
		Lactic acid bacteria	0.69
		Pseudomonas spp.	2.72
Sage—0.2% v/w	Chicken	Anaerobic bacteria	1.13	[48]
		Enterobacteriaceae	3.62
		Lactic acid bacteria	0.81
		Pseudomonas spp.	2.72
0.1% w/w	Mechanical Separated Meat (MSM) from chicken	Mesophilic bacteria	1.2	[49]
		Psychrotrophic bacteria	0.3
		Enterobacteriaceae	2.4
		Coliforms	2.3
		Enterococci bacteria	1.4
Savory—0.2% v/w	Chicken	Total viable counts	0.8	[39]
		Enterobacteriaceae	1
		Lactic acid bacteria	0
Sweet lemon—500 ppm	Sausage	Total viable count	0.03	[50]
		Pseudomonas spp.	0.05
		Psychrotrophic bacteria	0.04
		Lactic acid bacteria	0.08
		Enterobacteriaceae	0.11
Thyme—500 ppm	Sausage	Total viable count	1.75	[50]
		Pseudomonas spp.	0.85
		Psychrotrophic bacteria	1.69
		Lactic acid bacteria	1.18
		Enterobacteriaceae	0.09
0.5%, 1%	Minced beef	A. flavus	2.25–2.64 5	[37]

The synergistic effect of anti-microbial agents or their component, where it has been studied, is not cited. ¹ The difference of population that is cited is sometimes an approximate number, because of lack of exact data; ² Where the range of population difference is cited it corresponds to the different experimental conditions studied (e.g., different concentrations, storage temperatures, etc.); ³ Where the anti-microbial agents were combined with other preservation methods, the effect of the agent alone is cited; ⁴ These classifications apply to the end point of each experiment; ⁵ The population difference cited corresponds to the 3rd day of the experiment, because of lack of data for the control sample; ⁶ The population difference cited corresponds to the 8th day of the experiment, because of lack of data for the control sample; ⁷ The population of total mesophilic bacteria was converted from CFU/g to Log₁₀ CFU/g.