Overview of plant extracts as natural preservatives in meat

Abstract

Plant extracts are obtained by extracting bioactive compounds from various plant sources such as leaves, seeds, fruits, roots, stems, and agro-industry byproducts. These are rich sources of bioactive molecules such as polyphenols (flavonols, anthocyanins,

Natural Antimicrobials: A Clean Label Strategy to Improve the Shelf Life and Safety of Reformulated Meat Products

“…A common feature of these phenolic compounds is the presence of one or more aromatic rings in their structure, and one or more -OH groups, which are essential for antibacterial properties. Common phenolic compounds include phenolic acids (ferulic, p-coumaric, ellagic, rosmarinic, caffeic, and gallic acids), phenolic diterpenes (carnosic and carnosol acids), flavonoids (quercetin, catechin, rutin, and kaempferol) ( Figure 2 ), and volatile essential oils (menthol, carvacrol, thymol, eugenol, cymene, pinene, terpinene, cinnamaldehyde, camphor, and linalool) [ 33 , 53 , 79 ]. Thus, taking into account their properties (lipophilic or hydrophilic character) and composition, plant-based compounds could be subdivided into extracts (normally hydrophilic, obtained by aqueous or hydroalcoholic extractions) and essential oils (lipophilic character, obtained using distillation procedures or extractions with organic solvents).…”

“…Additionally, the use of plant extracts instead of the direct addition of plant powders has multiple advantages. The bioactive molecules are concentrated form in these extracts; thus, they can exert their potent antimicrobial activity at lower concentrations [ 33 ], increase the stability of the antimicrobials, reduce transport and storage costs, homogenize their composition, and facilitate their application in meat products. Nevertheless, the polyphenol mixtures are more effective than single compounds; thus, the application of plant extracts is more convenient rather than individual compounds [ 26 ].…”

“…In fact, the use of vegetable extracts, which naturally contain high nitrate amounts, was proposed to replace this additive [ 30 , 31 , 32 ]. In this regard, lettuce, celery, chard, spinach, or beet extracts were used [ 33 ]. The controlled fermentation of nitrate-rich extracts is also common in pre-converting said nitrates into nitrites and ensuring complete control of the nitrate/nitrite content during meat product processing [ 34 , 35 , 36 ], since otherwise, there are multiple variables (e.g., the degree of fermentation, the initial nitrate content, pro-/antioxidants in meat product formulation, etc.)…”

“…that can greatly vary the nitrate/nitrite conversion efficiency and the residual content of nitrites in the final product. Moreover, the plant extracts used as nitrite replacers reduce residual nitrite and N-nitrosamine formation [ 33 ]. This allows for the elaboration of meat products without or with reduced nitrite content.…”

“…Several synthetic preservatives were used for decades to delay microbial activity and to ensure microbial stability, but there are concerns about their toxicity in humans [ 41 ]. Thus, natural compounds with preservative activities gained popularity due to their health benefits, environmental issues, and consumer demand [ 33 ].…”