辛香料精油在食品保藏中的应用研究进展

文章综述了近年来国内外对于辛香料精油在抑菌方面的研究,以及在果蔬采后保藏及肉品保藏方面的应用性研究进展。辛香料精油对多种食源性致病细菌和真菌均具有很好的抑菌效果,是一种高效、安全的食品防腐剂来源。     

Use of Cymbopogon citratus essential oil in food preservation: Recent advances and future perspectives

The economic burdens and health implications of food spoilage are increasing. Contamination of food sources by fungi, bacteria, yeast, nematodes, insects, and rodents remains a major public health concern. Research has focused on developing safer natural products and innovations to meet consumers' acceptance as alternatives to synthetic food preservatives. Many recent novel preservative techniques and applications of both natural and synthetic origin continue to proliferate in food and chemical industries. In particular, some essential oils of plant origin are potent food preservatives and are thus attractive alternatives to synthetic preservatives. This paper provides an overview of recent advances and future prospects in assessing the efficacy of the use of Cymbopogon citratus (lemongrass) essential oil in food preservation. The possible mechanisms of action and toxicological profile as well as evidence for or against the use of this essential oil as an alternative to synthetic food preservatives in domestic and industrial applications are discussed.     

Encapsulation of coriander essential oil in cyclodextrin nanosponges: A new strategy to promote its use in controlled-release active packaging

In this work, we exploit the antimicrobial properties of coriander essential oil (CEO) incorporated in dextrin-derived nanosponges to create a stable controlled release system. Nanosponges (CD-NS) were loaded with CEO, characterized by means of scanning and transmission electron microscopy (SEM and TEM) and X-ray diffraction (XRD), and tested for their antimicrobial activity against foodborne pathogens. A head-space-solid phase microextraction coupled to gas chromatography (HS-SPME-GC–MS) method to assess CEO five major compounds was successfully validated. CEO loading was dependent on solvent and CD-NS choice. Additionally, CEO incorporation in CD-NS increased its crystallinity. While β-CD-NS and HP-β-CD:β-CD-NS incorporated higher CEO amounts than α-NS, the later proved more effective regarding their antimicrobial activity. CEO-α-CD-NS and CEO-HP-β-CD:β-CD-NS revealed a predominant bactericidal activity, CEO-β-CD-NS only exhibited a bacteriostatic action. We describe, for the first time, the incorporation of whole EOs in CD-NS and their ability to provide a controlled oil release, especially in the cases of β-derived-CD-NS, while inhibiting bacterial growth, creating a potential new strategy to overcome the poor efficacy of current antimicrobial food packaging.Industrial relevanceThe manufacturing of antimicrobial food packages is still hindered by the problems posed by its lack of efficiency and poor compound stability. The fact that the cyclodextrin nanosponges synthetized in this work can provide a controlled release of antimicrobial active agent, in this case, coriander essential oil while preserving this compound's antimicrobial activity against foodborne pathogens can open the doors for its use in antimicrobial food packaging films. Furthermore, given that cyclodextrin nanosponges are stable at temperatures over 200 °C, gives the packaging industry the opportunity of incorporating this technology during the extrusion process of film making, making the process of active packaging materials cheaper, faster and more readily scalable.     

植物精油纳米包埋技术的作用机制及其在肉品保鲜中的应用

肉中含有丰富的营养物质且水分活度高,在运输贮藏及销售过程中极易被氧化和腐败变质。因此,肉品保鲜成为食品工业的一大挑战。植物精油作为天然的食品防腐保鲜剂,具有良好的抑菌、抗氧化功效,在肉品保鲜领域具有一定的潜力。但因其水溶性和稳定性较差,限制了在肉品保鲜领域的广泛应用。本文综述了植物精油的抗菌和抗氧化能力及作为肉品保鲜剂所面临的问题、纳米包埋植物精油的方法及对食源性微生物的作用机制。本文通过对纳米包埋植物精油的开发和应用进行展望,为探究新型肉品保鲜剂提供参考。     

芳香精油在食品保藏中的应用性研究进展

芳香精油是重要的植物次生代谢物,药食应用历史悠久,因其多方面的生物活性,已引起人们对其在食品保藏领域替代化学防腐剂的极大兴趣。文中概述了芳香精油及其成分在采后果蔬、预切果蔬片、肉制品、乳制品和水产品等食品保鲜和贮藏领域中应用性和安全性研究的最新研究进展。许多研究表明,牛至、丁香、罗勒、胡荽、肉桂、百里香、薄荷、迷迭香、芥茉、芫荽、红根草等芳香精油以及丁子香酚、香芹酚、肉桂酸、己醛、草蒿脑、麝香草酚、香芹酮、肉桂醛、柠檬醛、香叶醇等单体成分具有优良的抗食源性腐败菌和致病菌活性。通过与食品生产前处理工艺、气调包装、配方优化等手段的结合,一些芳香精油及其成分显示出天然食品保藏剂良好的商用价值。     

Effect of grape pomace extracts obtained from different grape varieties on microbial quality of beef patty

Grape pomace extracts were obtained from 5 different grape varieties grown in Turkey. The extracts were concentrated to obtain crude extracts; and incorporated into beef patties at 0% (Control), 1%, 2%, 5%, and 10% concentrations to test their antimicrobial effects in different storage periods (first, 12, 24, and 48 h). The numbers of microorganism were generally decreased by the extract concentration during the storage period. All the microorganisms tested were inhibited by the extract concentration of 10% in all the storage periods. Furthermore, the foodborne pathogens including Enterobacteriaceae and coliform bacteria, and the spoilage microorganisms including yeasts and moulds and lipolytic bacteria were also inhibited by 5% of Emir, Gamay, and Kalecik Karasi varieties in beef patties. Considering the results, the extracts of grape pomaces might be a good choice in the microbial shelf life extension of the food products as well as inhibiting the food pathogens as the case of beef patties. PRACTICAL APPLICATION: Grape pomace consists of seeds, skins, and stems, and an important by-product that is well known to be the rich source of phenolic compounds, both flavonoids and non-flavonoids. These substances have considerable beneficial effects on human health. The use of natural antimicrobial compounds, like plant extracts of herbs and spices for the preservation of foods has been very popular issue because of their antimicrobial activity. Therefore, grape pomace should be added into some food formulations to benefit from their protective effects. In this respect, this study reports the effect of addition of grape pomace extracts obtained from different grape varieties on microbial quality of beef patty. The results obtained in this study may be useful for food industry, which has recently tended to use natural antimicrobial sources in place of synthetic preservatives to prevent microbial spoilage.     

Development of Wide-Spectrum Hybrid Bacteriocins for Food Biopreservation

The food industry demands new procedures and methods to produce minimally processed, ready to eat food with intact nutritional, taste, and flavor properties. The biopreservation and the use of both bacteriocins produced by lactic acid bacteria (LAB) and bacteriocinogenic strains as an alternative to substitute chemical antimicrobial for food preservation became increasingly important in the last two decades. When the new proposed natural preservatives techniques are applied, probiotics food can be obtained and, simultaneously, foodborne pathogens and spoilage contaminants can diminish. However, bacteriocins produced by LAB have a narrow antibacterial spectrum and are inactive against Gram-negative bacteria like Salmonella and the emergent enterohemorrhagic Escherichia coli. Knowing the mechanism of action and the structural features of microcins synthesized by Gram-negative bacteria and with potent antimicrobial activity against the mentioned microorganism, the proposal is to obtain hybrid peptides (microcin–bacteriocin) with broad antimicrobial spectrum. This review explains how the inability of bacteriocins to cross the outer membrane of Gram-negative bacteria unable them to act on the bacteria. It will also be discussed how a hybrid bacteriocin can be obtained.     

Plant extracts for the control of bacterial growth: efficacy, stability and safety issues for food application

The microbial safety of foods continues to be a major concern to consumers, regulatory agencies and food industries throughout the world. Many food preservation strategies have been used traditionally for the control of microbial spoilage in foods but the contamination of food and spoilage by microorganisms is a problem yet to be controlled adequately. Although synthetic antimicrobials are approved in many countries, the recent trend has been for use of natural preservatives, which necessitates the exploration of alternative sources of safe, effective and acceptable natural preservatives. Plants contain innumerable constituents and are valuable sources of new and biologically active molecules possessing antimicrobial properties. Plants extracts either as standardized extracts or as a source of pure compounds provide unlimited opportunities for control of microbial growth owing to their chemical diversity. Many plant extracts possess antimicrobial activity against a range of bacteria, yeast and molds, but the variations in quality and quantity of their bioactive constituents is the major detriments in their food use. Further, phytochemicals added to foods may be lost by various processing techniques. Several plant extracts or purified compounds intended for food use have been consumed by humans for thousands of years, but typical toxicological information is not available for them. Although international guidelines exist for the safety evaluation of food additives, owing to problems in standardization of plant extracts, typical toxicological values have not been assigned to them. Development of cost effective isolation procedures that yield standardized extracts as well as safety and toxicology evaluation of these antimicrobials requires a deeper investigation.     

Potential of Medicinal Plants as Antimicrobial and Antioxidant Agents in Food Industry: A Hypothesis

Many food preservation strategies can be used for the control of microbial spoilage and oxidation; however, these quality problems are not yet controlled adequately. Although synthetic antimicrobial and antioxidant agents are approved in many countries, the use of natural safe and effective preservatives is a demand of food consumers and producers. This paper proposes medicinal plants, traditionally used to treat health disorders and prevent diseases, as a source of bioactive compounds having food additive properties. Medicinal plants are rich in terpenes and phenolic compounds that present antimicrobial and antioxidant properties; in addition, the literature revealed that these bioactive compounds extracted from other plants have been effective in food systems. In this context, the present hypothesis paper states that bioactive molecules extracted from medicinal plants can be used as antimicrobial and antioxidant additives in the food industry.     

基于高通量测序分析昆明官渡区市售芫荽细菌污染状况

目的 为判断芫荽是否是潜在的食源性疾病传播媒介,并探索高通量测序技术在食品微生物检测中应用的可行性。方法 以昆明市官渡区超市及农贸市场售芫荽为样本,采用高通量16S rDNA扩增子测序技术结合FAPROTAX 功能群体预测分析市售芫荽样品细菌多样性,重点关注潜在致病菌以及人类肠道菌群。结果 从全部样品共获得833个OTUs（Operational Taxonomic Units,操作分类单元）,经物种注释可归入细菌的19个门、288个属。其中,在全部或部分芫荽样品中检测到以下潜在致病菌OTUs ：致腹泻和肠胃炎细菌,如布氏弓形杆菌、脆弱拟杆菌、产碱普罗威登斯菌等;致医院感染条件致病菌,如抗辐射不动杆菌、土壤不动杆菌和奥斯陆莫拉氏菌。此外还检测到多种人类肠道菌群的OTUs,如产气柯林斯菌、长链多雷尔氏菌、大肠埃希氏菌等。结论 简单焯水或清洗后食用芫荽的饮食习惯存在巨大的食品安全隐患,芫荽可能已成为食源性疾病传播的一条重要途径但并未受到足够重视。     

Potential of Immobilization Technology in Bacteriocin Production and Antimicrobial Packaging

Globalization of food trade, increasing demand for ready to eat fresh food products, and awareness among consumers towards side effects of chemical preservatives have led to research and development in the area of biopreservation. Biopreservation basically involves inhibition or killing of food spoilage microorganisms by the application of other microbes or their antimicrobial products. Bacteriocins are ribosomally synthesized peptides having potential as biopreservatives. The enhanced, stable, continuous, and economically viable production of these preservatives can be carried out by employing immobilization technology. Various matrices, operational conditions, and fermentation systems have been explored for achieving maximum bacteriocin production through immobilization; besides these, immobilization can be used for the application of bacteriocins in various packaging materials or films for their functional effects at the surface of different food products. Efficiency of an antimicrobial packaging system can be increased by its application in combination with other methods, including high-pressure processing (HPP), which in turn can improve the shelf life of food products. These antimicrobial packaging systems can play a significant role in extending shelf life of food products by reducing the risk of foodborne pathogens, thereby enhancing their quality and safety.     

Self-preserving cosmetics

Preservatives are added to products for two reasons: first, to prevent microbial spoilage and therefore to prolong the shelf life of the product; second, to protect the consumer from a potential infection. Although chemical preservatives prevent microbial growth, their safety is questioned by a growing segment of consumers. Therefore, there is a considerable interest in the development of preservative-free or self-preserving cosmetics. In these formulations traditional/chemical preservatives have been replaced by other cosmetic ingredients with antimicrobial properties that are not legislated as preservatives according to the Annex VI of the Commission Directive 76/768/EEC and the amending directives (2003/15/EC, 2007/17/EC and 2007/22/EC). 'Hurdle Technology', a technology that has been used for the control of product safety in the food industry since 1970s, has also been applied for the production of self-preserving cosmetics. 'Hurdle Technology' is a term used to describe the intelligent combination of different preservation factors or hurdles to deteriorate the growth of microorganisms. Adherence to current good manufacturing practice, appropriate packaging, careful choice of the form of the emulsion, low water activity and low or high pH values are significant variables for the control of microbial growth in cosmetic formulations. This paper describes the application of the basic principles of 'Hurdle Technology' in the production of self-preserving cosmetics. Multifunctional antimicrobial ingredients and plant-derived essential oils and extracts that are used as alternative or natural preservatives and are not listed in Annex VI of the Cosmetic Directive are also reported.     

二种可食用精油的抗菌活性研究

对生姜和芫荽叶两种可食用精油的抗菌活性进行了研究.采用水蒸汽同步蒸馏法提取精油,以抗生素为参比,运用琼脂孔洞法测定生姜块茎和芫荽茎叶精油抗6种食源性致病菌和2种腐败真菌的抑菌圈直径.结果表明,生姜和芫荽精油均表现程度不等的广谱抗菌活性.生姜精油对肺炎克雷伯菌、志贺氏菌、金黄色葡萄球菌、黑曲霉和假丝酵母具有良好的抗菌作用...     

Antimicrobial properties and mode of action of mustard and cinnamon essential oils and their combination against foodborne bacteria

In this work, the effects of cinnamon and mustard essential oils against nine foodborne bacteria were evaluated. Their antimicrobial susceptibility and action mechanism was also assessed. Additionally, the effects of the combination between both were evaluated. To provide data on the in vitro action of essential oils, the transfer mechanism was assessed using gas chromatography–mass spectrometry. The results indicated that the mustard presents 10 times more bactericidal/bacteriostatic effect than cinnamon essential oil. In both cases the action mechanism happened intracellularly, but since mustard induces cell cycle arrest, cinnamon produces protrusions and aggregation. The combinatorial assays demonstrated in most cases an additive effect. In addition, synergies for P. putida and E. coli OI57:H7 were shown. Therefore, to introduce them in combination, could be a great way to make a natural-active packaging. The distinct activity profiles can be explained by their transfer mechanism that involves vapour release and agar diffusion.Industrial relevanceThe industry is focused on improving food safety by controlling the growth of foodborne and food spoilage microorganisms and by reducing the use of synthetic preservatives. The novelty of this research article lies in the study of antimicrobial activity of two natural active agents (mustard and cinnamon essential oil), separately and in combination, against nine foodborne bacteria; as well as the study of its mechanism of action and transfer. The set of all outcomes give the necessary information to be able to design a novel food active packaging based on the applied microbiology studied.     

天然抗菌剂纳米乳液的制备、抑菌机理及在肉类保鲜中的应用研究进展

肉类富含蛋白质、脂肪等营养物质,在加工或贮藏过程中易受到微生物的污染而发生腐败变质。天然抗菌剂作为一种肉类保鲜剂,因具有良好的抑菌活性、安全性及生物可降解性而受到广泛关注。然而,有些天然抗菌剂具有高挥发性、低水溶性、热不稳定等缺陷,导致其在肉类保鲜中的应用受到局限。纳米乳液作为一种包埋系统,能够将天然抗菌剂包埋在其内部,以提高天然抗菌剂的稳定性和抑菌活性,并改善天然抗菌剂的释放性能,从而缓解天然抗菌剂的局限性。本文综述天然抗菌剂纳米乳液的构成和制备方法,并在此基础上进一步论述天然抗菌剂纳米乳液的抑菌机理与优势以及天然抗菌剂纳米乳液在肉类保鲜中的研究进展,以期为天然抗菌剂纳米乳液在肉类保鲜中的应用提供理论基础和实践指导。     

Antimicrobial and antibiofilm activities of procyanidins extracted from laurel wood against a selection of foodborne microorganisms

This study aimed to evaluate the antimicrobial and antibiofilm activities of two procyanidins isolated from an ethyl acetate extract of laurel wood against a selection of foodborne pathogens. The analysis of the extract by HPLC–DAD/ESI–MS allowed us to detect the presence of two procyanidins, which were selectively isolated and identified by chromatographic and spectroscopic means as cinnamtannin B‐1 ( 1 ) and procyanidin B‐2 ( 2 ). Procyanidins 1 and 2 exhibited two biological activities: inhibition of bacterial growth at high concentrations and prevention of biofilm formation at lower concentrations. Synergistic effect was also detected when both compounds were tested in combination against Listeria monocytogenes. Significant effects were also detected on disruption of preformed biofilm. The ability of procyanidins to inhibit microbial growth and biofilm formation and to synergistically work with each other may stimulate a market as natural food preservatives, and/or natural sanitisers for processing equipment where foodborne pathogens reside.     

Bacteriocin-based strategies for food biopreservation

Bacteriocins are ribosomally-synthesized peptides or proteins with antimicrobial activity, produced by different groups of bacteria. Many lactic acid bacteria (LAB) produce bacteriocins with rather broad spectra of inhibition. Several LAB bacteriocins offer potential applications in food preservation, and the use of bacteriocins in the food industry can help to reduce the addition of chemical preservatives as well as the intensity of heat treatments, resulting in foods which are more naturally preserved and richer in organoleptic and nutritional properties. This can be an alternative to satisfy the increasing consumers demands for safe, fresh-tasting, ready-to-eat, minimally-processed foods and also to develop "novel" food products (e.g. less acidic, or with a lower salt content). In addition to the available commercial preparations of nisin and pediocin PA-1/AcH, other bacteriocins (like for example lacticin 3147, enterocin AS-48 or variacin) also offer promising perspectives. Broad-spectrum bacteriocins present potential wider uses, while narrow-spectrum bacteriocins can be used more specifically to selectively inhibit certain high-risk bacteria in foods like Listeria monocytogenes without affecting harmless microbiota. Bacteriocins can be added to foods in the form of concentrated preparations as food preservatives, shelf-life extenders, additives or ingredients, or they can be produced in situ by bacteriocinogenic starters, adjunct or protective cultures. Immobilized bacteriocins can also find application for development of bioactive food packaging. In recent years, application of bacteriocins as part of hurdle technology has gained great attention. Several bacteriocins show additive or synergistic effects when used in combination with other antimicrobial agents, including chemical preservatives, natural phenolic compounds, as well as other antimicrobial proteins. This, as well as the combined use of different bacteriocins may also be an attractive approach to avoid development of resistant strains. The combination of bacteriocins and physical treatments like high pressure processing or pulsed electric fields also offer good opportunities for more effective preservation of foods, providing an additional barrier to more refractile forms like bacterial endospores as well. The effectiveness of bacteriocins is often dictated by environmental factors like pH, temperature, food composition and structure, as well as the food microbiota. Foods must be considered as complex ecosystems in which microbial interactions may have a great influence on the microbial balance and proliferation of beneficial or harmful bacteria. Recent developments in molecular microbial ecology can help to better understand the global effects of bacteriocins in food ecosystems, and the study of bacterial genomes may reveal new sources of bacteriocins.     

Composition and Antibacterial Activity of Essential Oils of Flos Sophorae Immaturus

Essential oil was extracted from Flos Sophorae Immaturus (FSI) by simultaneous distilling-extraction (SDE) and vapor-distillation extraction (VDE), gave a yield of 2 and 1.2 mg/g, based on GC/MS analysis, 44 and 29 components were identified in SDE and VDE extracts, respectively. Essential oil extracted by SDE was active against common foodborne pathogens, however, it did not show any activity against fungus. The minimal lethal concentration (MLC) was 0.39 μL/mL using the spread-plate method. The antibacterial activity might be due to phenols, such as eugenol in the essential oil. For essential oil-treated Staphylococcus aureus, pretreatment with potassium sorbate, sodium benzoate, or the essential oil markedly lowered bacterial count (p < 0.05), suggesting that FSI essential oil might be used in food preservation to reduce the concentration of chemical preservatives.     

Assessment of Pelargonium graveolens oil as plant‐based antimicrobial and aflatoxin suppressor in food preservation

BACKGROUND: Contamination of stored food commodities by moulds and mycotoxins results in qualitative as well as quantitative losses. Most of the synthetic antimicrobials used for preservation of stored food items produce side effects in the form of residual and mammalian toxicity. Recently some higher plant products have been recommended as safe alternatives of such synthetic antimicrobials. In the present investigation antifungal efficacy of some essential oils was evaluated against two toxigenic strains of Aspergillus flavus with special reference to the oil of Pelargonium graveolens to investigate its potential to inhibit aflatoxin B₁ secretion. RESULTS: Essential oil of P. graveolens exhibited absolute fungitoxicity against both the toxigenic strains of A. flavus. The minimum inhibitory concentration of the oil was found to be 0.75 g L^?1 and exhibited a fungistatic nature. It was found superior over the synthetic fungicides tested and exhibited a broad fungitoxic spectrum. The oil showed excellent anti‐aflatoxigenic efficacy as it completely inhibited aflatoxin B₁ production even at 0.50 g L^?1. CONCLUSION: This is the first report on the aflatoxin B₁ inhibitory nature of P. graveolens oil. It may be recommended as a novel plant‐based antimicrobial as well as aflatoxin B₁ suppressor over synthetic preservatives in food protection. Copyright © 2008 Society of Chemical Industry