脂肪替代物及其在肉制品中的应用

传统的肉制品中含有大量的脂肪,脂肪赋予肉制品良好的风味和多汁的口感,而过量的摄食脂肪会导致肥胖症、高血压及某些癌症的发生.脂肪替代品在肉制品中的应用既减少了脂肪含量又弥补了口味的损失.本文论述了脂肪替代物及其在肉制品中的应用情况,以望为肉品加工业提供一些理论基础.     

肉和肉制品中脂质氧化的研究进展

肉和肉制品在加工、贮藏和运输的过程中容易发生脂质氧化,影响肉制品的品质。脂质适度氧化可以促进肉制品的风味,但是脂质过度氧化还可能产生有毒有害物质,增加食用风险。脂质氧化反应产生的初级产物及次级产物化学性质不稳定,容易与肉中的其他成分(蛋白质、血红素、抗氧化添加剂等)发生反应从而影响肉制品的品质。因此,调控脂质氧化对肉及肉制品来说非常重要。本文主要综述了脂质的酶促氧化、自动氧化、脂质氧化与蛋白质氧化之间的关系。大量研究表明,脂质氧化过程复杂且受诸多因素和条件的影响,研究氧化过程及氧化机制对调控脂质氧化和提高食品品质的稳定性具有重要意义。     

Evaluation of three 2-thiobarbituric acid methods for the measurement of lipid oxidation in various meats and meat products

The aim of this work was to study the influence of different conditions on the 2-thiobarbituric acid (TBA) number, determined by the extraction and distillation method, as a measure of lipid oxidation in various meats and meat products. Different extracting agents (trichloroacetic acid and perchloric acid), different reaction times (20, 30, 40, 50 and 60 min) and the effect of sulfanilamide additions were evaluated. Significant differences with respect to reaction times were found. The best results were generally obtained with 40 min at 80 ± 2 °C. Different values were found between samples with and without the addition of sulfanilamide.     

肉食品中的胆固醇氧化物

胆固醇是肌肉组织的一种组分。新鲜肉中不存在胆固醇氧化物。内在长期贮存和加热中生成胆固醇氧化物。肉食品中的胆固醇氧化物对人的健康有害。肉中胆固醇氧化物的总量与肉的脂类氧化物存在着线性相关。在饲料中添加生育酚以提高内源性生育酚，其动物的肉制品中胆固醇氧化物明显减少。     

Cholesterol oxide, cholesterol, total lipid and fatty acid contents in processed meat products during storage

The effects of storage time on the formation of cholesterol oxides and on alterations in the fatty acid composition of processed meat products manufactured by Brazilian industries were investigated in this study. Cholesterol oxides and cholesterol were determined by HPLC using photodiode array and refractive index detectors. Samples of jerked beef, Italian-type salami, chicken mortadella and Chester mortadella were analysed at 30 day intervals starting at zero time, for 90 days for the mortadella and 120 days for the jerked beef and salami. The mortadellas were stored under refrigeration at 6 °C and the jerked beef and salami at room temperature, but protected from the light. No cholesterol oxides were formed during the storage time in any of the samples. The cholesterol content, the fatty acid composition and total lipid contents showed no significant differences during storage with the exception of the total lipid content of the jerked beef, which varied from 3.5 at zero time to 2.4 g/100 g after 120 days storage.     

Authentication of meat and meat products

In recent years, interest in meat authenticity has increased. Many consumers are concerned about the meat they eat and accurate labelling is important to inform consumer choice. Authentication methods can be categorised into the areas where fraud is most likely to occur: meat origin, meat substitution, meat processing treatment and non-meat ingredient addition. Within each area the possibilities for fraud can be subcategorised as follows: meat origin—sex, meat cuts, breed, feed intake, slaughter age, wild versus farmed meat, organic versus conventional meat, and geographic origin; meat substitution—meat species, fat, and protein; meat processing treatment—irradiation, fresh versus thawed meat and meat preparation; non-meat ingredient addition—additives and water. Analytical methods used in authentication are as diverse as the authentication problems, and include a diverse range of equipment and techniques. This review is intended to provide an overview of the possible analytical methods available for meat and meat products authentication. In areas where no authentication methods have been published, possible strategies are suggested.     

Advances in ingredient and processing systems for meat and meat products

Changes in consumer demand of meat products as well as increased global competition are causing an unprecedented spur in processing and ingredient system developments within the meat manufacturing sector. Consumers demand healthier meat products that are low in salt, fat, cholesterol, nitrites and calories in general and contain in addition health-promoting bioactive components such as for example carotenoids, unsaturated fatty acids, sterols, and fibers. On the other hand, consumers expect these novel meat products with altered formulations to taste, look and smell the same way as their traditionally formulated and processed counterparts. At the same time, competition is forcing the meat processing industry to use the increasingly expensive raw material “meat” more efficiently and produce products at lower costs. With these changes in mind, this article presents a review of novel ingredient systems and processing approaches that are emerging to create high quality, affordable meat products not only in batch mode but also in large-scale continuous processes. Fat replacers, fat profile modification and cholesterol reduction techniques, new texture modifiers and alternative antioxidant and antimicrobial systems are being discussed. Modern processing equipment to establish continuously operating product manufacturing lines and that allow new meat product structures to be created and novel ingredients to be effectively utilized including vacuum fillers, grinders and fine dispersers, and slicers is reviewed in the context of structure creation in meat products. Finally, trends in future developments of ingredient and processing systems for meat products are highlighted.     

Conjugated linoleic acid in meat and meat products: A review

Conjugated linoleic acid (CLA) consists of a group of geometric and positional isomers of linoleic acid to which anticancerogenic, antidiabetic, and antiatherogenic effects, as well as effects on immune system, bone metabolism, and body composition are attributed. CLA is found predominantly in milk and meat of ruminants due to the importance of rumen micro-organism in the formation of CLA and its precursors. This review attempts to give an overview of the available data on intramuscular CLA concentrations in meat and meat products originating from different animal species. The factors influencing these concentrations are discussed and the estimated human daily intakes as well as the percentage provided by meat are reported.     

Effect of solvent to sample ratio on total lipid extracted and fatty acid composition in meat products within different fat content

The effect of solvent to sample ratio on total extracted lipids and fatty acid (FA) composition in meat products with different fat contents was evaluated. Total lipids were extracted according to the Folch et al. (1957) method, using a 20:1 ratio of chloroform:methanol (2:1, v/v) to sample (A), and also testing the solvent:sample ratio of 10:1 (B). Higher amounts of total lipids and total FA from neutral lipids were obtained using the A ratio, which could be due to an insufficient chloroform:dry-weight sample proportion which could be insufficient for solubilizing the total amount of lipids. In the polar lipid fraction, the total amount of FA was higher using the B rather than the A ratio, which may be caused by the higher volume of added water when using A than B. When studying the FA composition of different lipid fractions, the volume of both the solvent and the water for total lipid extraction should be considered.     

Stability of catalase and its potential role in lipid oxidation in meat

The activity of catalase in microbial growth-controlled and uncontrolled ground beef muscle (semimembranosus, SM) did not change (P>0.05) during 6-day storage at 4°C. Likewise, catalase activity in ground, beef SM and longissimus dorsi (LD), pork LD, and chicken breast (B) and thigh (T) muscles was not affected (P>0.05) by 2-month storage at −20°C, with or without mid-month thawing/refreezing. When sodium azide (a catalase inhibitor) was added to ground beef SM, lipid oxidation (as measured by peroxide values) during 4-day refrigeration was higher (P<0.05) in treated samples — 43 and 55% higher at day 2 and day 4, respectively — than in the controls. It was concluded that catalase would be stable during meat storage/distribution and contribute significantly to the antioxidative process in raw meat products.     

Chemical safety of meat and meat products

Since the Second World War the consumer behaviour in developed countries changed drastically. Primarily there existed the demand for sufficient food after a period of starvation, afterwards the desire for higher quality was arising, whereas today most people ask for safe and healthy food with high quality. Therefore a united approach comprising consistent standards, sound science and robust controls is required to ensure consumers' health and to maintain consumers' confidence and satisfaction. Chemical analysis along the whole food chain downstream (tracking) from primary production to the consumer and upstream (tracing) from the consumer to primary production is an important prerequisite to ensure food safety and quality. In this frame the focus of the following paper is the “chemical safety of meat and meat products” taking into account inorganic as well as organic residues and contaminants, the use of nitrite in meat products, the incidence of veterinary drugs, as well as a Failure Mode and Effect Analysis (FMEA) system assessing (prioritizing) vulnerable food chain steps to decrease or eliminate vulnerability.     

超市肉类加工食品酸价安全期与氧化安全期比较

对超市出售的鱿鱼丝、肉片、鱼片、卤鸡腿、火腿肠、午餐肉罐头、广式腊肠7大类15种肉类加工食品的营养组成、酸价(AV)、过氧化值(POV)、硫代巴比妥酸值(TBA)以及感官品质进行测定和分析,根据国标对被测食品的酸价安全期和氧化安全期进行分析比较.在保存期为货架期的1/3～1/2时,盐焗卤制鸡腿、广式腊肠、油炸牛肉干、火腿肠、鱿鱼丝、鱼片等9个样品的感官评分为良好,但其AV已接近或超过酸价国标值,AV安全期仅为货架期的1/5～1/3;同样的产品,其POV值却大大低于国标值,POV氧化安全期多数超过货架期;TBA值与感官评分结果相近,TBA氧化安全期比较接近于货架期.结果表明,AV不宜作为肉类加工食品安全指标,POV因其不稳定性,也不宜作为氧化安全指标,TBA值因其具有安全学意义并更接近于氧化安全实际,可作为肉类加工食品的氧化安全指标.     

Plant extracts as natural antioxidants in meat and meat products

Antioxidants are used to minimize the oxidative changes in meat and meat products. Oxidative changes may have negative effects on the quality of meat and meat products, causing changes in their sensory and nutritional properties. Although synthetic antioxidants have already been used but in recent years, the demand for natural antioxidants has been increased mainly because of adverse effects of synthetic antioxidants. Thus most of the recent investigations have been directed towards the identification of natural antioxidants from various plant sources. Plant extracts have been prepared using different solvents and extraction methods. Grape seed, green tea, pine bark, rosemary, pomegranate, nettle and cinnamon have exhibited similar or better antioxidant properties compared to some synthetic ones. This review provides the recent information on plant extracts used as natural antioxidants in meat and meat products, specifically red meat.     

Lipid content of frozen fish: Comparison of different extraction methods and variability during freezing storage

In this work, a microwave-assisted extraction (MAE) methodology was compared with several conventional extraction methods (Soxhlet, Bligh & Dyer, modified Bligh & Dyer, Folch, modified Folch, Hara & Radin, Roese-Gottlieb) for quantification of total lipid content of three fish species: horse mackerel (Trachurus trachurus), chub mackerel (Scomber japonicus), and sardine (Sardina pilchardus). The influence of species, extraction method and frozen storage time (varying from fresh to 9 months of freezing) on total lipid content was analysed in detail.The efficiencies of methods MAE, Bligh & Dyer, Folch, modified Folch and Hara & Radin were the highest and although they were not statistically different, differences existed in terms of variability, with MAE showing the highest repeatability (CV = 0.034). Roese-Gottlieb, Soxhlet, and modified Bligh & Dyer methods were very poor in terms of efficiency as well as repeatability (CV between 0.13 and 0.18).     

Chitosan and mint mixture: A new preservative for meat and meat products

Meat is prone to both microbial and oxidative spoilage and therefore it is desirable to use a preservative with both antioxidant and antimicrobial properties. Mint extract alone had good antioxidant activity but poor antimicrobial activity, while chitosan alone showed poor antioxidant activity with excellent antimicrobial properties. Therefore, the potential of chitosan and mint mixture (CM), as a preservative for meat and meat products, was investigated. Addition of chitosan to mint extract did not interfere with the antioxidant activity of mint. In the case of 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, the IC₅₀ value for CM (17.8 μg/ml) was significantly (p ? 0.05) lower than that for mint extract (23.6 μg/ml). CM efficiently scavenged superoxide and hydroxyl radicals. The antimicrobial activities of CM and chitosan were comparable against the common food spoilage and pathogenic bacteria, the minimum inhibitory concentration being 0.05%. CM was more effective against Gram-positive bacteria. The shelf life of pork cocktail salami, as determined by total bacterial count and oxidative rancidity, was enhanced in CM-treated samples stored at 0–3 °C.     

Comparison of different methods to quantify fat classes in bakery products

The definition of fat differs in different countries; thus whether fat is listed on food labels depends on the country. Some countries list crude fat content in the ‘Fat’ section on the food label, whereas other countries list total fat. In this study, three methods were used for determining fat classes and content in bakery products: the Folch method, the automated Soxhlet method, and the AOAC 996.06 method. The results using these methods were compared. Fat (crude) extracted by the Folch and Soxhlet methods was gravimetrically determined and assessed by fat class using capillary gas chromatography (GC). In most samples, fat (total) content determined by the AOAC 996.06 method was lower than the fat (crude) content determined by the Folch or automated Soxhlet methods. Furthermore, monounsaturated fat or saturated fat content determined by the AOAC 996.06 method was lowest. Almost no difference was observed between fat (crude) content determined by the Folch method and that determined by the automated Soxhlet method for nearly all samples. In three samples (wheat biscuits, butter cookies-1, and chocolate chip cookies), monounsaturated fat, saturated fat, and trans fat content obtained by the automated Soxhlet method was higher than that obtained by the Folch method. The polyunsaturated fat content obtained by the automated Soxhlet method was not higher than that obtained by the Folch method in any sample.     

烹调方式对不同肉及其制品中杂环胺的影响概述

杂环胺(heterocyclic aromatic amines,HAAs)是一类杂环芳香族化合物,是富含蛋白质的食物(如肉类和鱼类等)在高温和长时间烹饪过程中产生的一类有害物质.目前已经从高温加工的肉及其制品中发现有超过30种的杂环胺.国际癌症研究机构已把2-氨基-3-甲基咪唑并[4,5-f]喹啉(IQ)等杂环胺列为...     

Strategies for designing novel functional meat products

In recent years, much attention has been paid to physiological functions of foods due to increasing concerns for health. Although there has been limited information of physiological functions of meat until recently, several attractive meat-based bioactive compounds, such as carnosine, anserine, l-carnitine, conjugated linoleic acid, have been studied. Emphasizing these activities is one possible approach for improving the health image of meat and developing functional meat products. This article provides potential benefits of representative meat-based bioactive compounds on human health and an overview of meat-based functional products. Strategies for designing novel functional meat products utilizing bioactive peptides and/or probiotic bacteria, is also discussed. This article focuses particularly on the possibility of meat protein-derived bioactive peptides, such as antihypertensive peptides. There are still some hurdles in developing and marketing novel functional meat products since such products are unconventional and consumers in many countries recognize meat and meat products to be bad for health. Along with accumulation of scientific data, there is an urgent need to inform consumers of the exact functional value of meat and meat products including novel functional foods.     

Application of near infrared reflectance spectroscopy to predict meat and meat products quality: A review

Over the past three decades, near infrared reflectance (NIR) spectroscopy has been proved to be one of the most efficient and advanced tools for the estimation of quality attributes in meat and meat products. This review focuses on the use of NIR spectroscopy to predict different meat properties, considering the literature published mainly in the last decade. Firstly, the potential of NIR to predict chemical composition (crude protein, intramuscular fat, moisture/dry matter, ash, gross energy, myoglobin and collagen), technological parameters (pH value; L*, a*, b* colour values; water holding capacity; Warner–Bratzler and slice shear force) and sensory attributes (colour, shape, marbling, odour, flavour, juiciness, tenderness or firmness) are reviewed. Secondly, the usefulness of NIR for classification into meat quality grades is presented and thirdly its potential application in the industry is shown. The review indicates that NIR showed high potential to predict chemical meat properties and to categorize meat into quality classes. In contrast, NIR showed limited ability for estimating technological and sensory attributes, which may be mainly due to the heterogeneity of the meat samples and their preparation, the low precision of the reference methods and the subjectivity of assessors in taste panels. Hence, future work to standardize sample preparation and increase the accuracy of reference methods is recommended to improve NIR ability to predict those technological and sensory characteristics. In conclusion, the review shows that NIR has a considerable potential to predict simultaneously numerous meat quality criteria.