霉菌发酵剂对干发酵香肠的理化指标、氧化程度及风味的影响

为探究将分离自传统宣威火腿中的霉菌作为优良发酵剂的可行性,将其中的枝孢菌P27作为发酵剂接种于干发酵香肠中,研究其对干发酵香肠理化性质、氧化程度以及风味的影响。结果表明,枝孢菌没有显著地改变干发酵香肠的pH和水分活度值,但使细菌总数显著降低,并且通过降低香肠硬度、增加香肠弹性而改善香肠质构。不同加工阶段接菌组香肠的脂肪氧化和蛋白质氧化程度显著低于空白组,说明枝孢菌具有一定的抗氧化能力。通过气质联用仪对发酵30 d后的干发酵香肠的风味物质进行检测,共检出23种物质,发现接菌组香肠的醇类、酯类、酮类和萜类等物质含量增多。综上所述,枝孢菌作为发酵剂可以减少干发酵香肠的杂菌含量、改善香肠质构、减缓香肠氧化、丰富香肠风味,未来可作为发酵剂应用于发酵肉制品的生产。     

上海颁布发酵肉制品地方标准

正发酵肉制品是指畜禽肉在自然或人工条件下经特定有益微生物发酵或酶的作用,加工制成的一类可即食的肉制品,如黎巴嫩大香肠、萨拉米香肠等。如今,发酵肉制品已由最初的依靠进口转向国内生产,且品种不断增多,生产数量也不断增加。然而,目前我国尚无发酵肉制品的安全质量标准,致使发酵肉制品的生产难以规范。为此,上海市食品药品监督管理局组织制定了上海市食品安全地方标准《发酵肉制品》。此标准范围涵盖了上海市所有发酵肉制品生产企业生产的产品,按加工工艺分为发酵灌肠制品和发酵火腿制品,按成品的生熟分为发酵生肉制品和发酵熟肉制品。     

干香肠与半香肠的质量控制

干香肠和半干香肠属于发酵类肉制品,多数是生食,因此加工这类产品必须有严格的原料选择和加工工艺。原料一定要新鲜的优质肉,每道加工工序和加工环节都有严格的要求,只有这样才能生产出高质量具有独特风味的发酵肉制品。     

微生物在发酵肉制品中的应用

发酵肉制品是指在自然或人工控制条件下利用微生物发酵作用,产生具有特殊风味、色泽和质地,且具有较长保存期的肉制品。 在欧美等国,发酵肉制品主要指干或半干香肠。但到目前为止,干或半干香肠还没有正式定义,人们只是根据香肠最终的干燥程度来划分两者。干香肠为经细菌作用,pH<5.3,再经干燥除去 25％～50％     

干香肠与半干香肠的质量控制

干香肠和半干香肠属于发酵类肉制品,多数是生食,因此加工这类产品时必须有严格的原料选择和加工工艺.原料一定要新鲜的优质肉,每道加工工序和加工环节都有严格的要求,只有这样才能生产出高质量具有独特风味的发酵肉制品.     

如何利用发酵剂加工肉类制品

<正>发酵肉制品,是指在自然或人工控制条件下,利用微生物的发酵作用,产生具有特殊风味、色泽和质地,且具有较长货架期的肉制品。传统的发酵肉制品其质量稳定性难以控制,且不适应大规模现代化生产。目前,国外已经普遍利用干腌或人工控制接种培养发酵的方法,用于生产干或半干香肠,或各种各样的火腿。 随着分子生物学研究的不断深入,近     

发酵香肠安全性的研究进展

本文着重介绍了发酵香肠中沙门氏菌、金黄色葡萄球菌、李斯特氏菌和生物胺对健康的危害以及将这些危害降到最低程度的措施.此外,对预测微生物学在发酵香肠安全中的应用作了讨论.     

羊肉发酵香肠的研制

为了获得质量、口感较好的羊肉发酵香肠,通过发酵剂适应性试验,选择用植物乳杆菌、啤酒片球菌和木糖葡萄球菌按一定比例混合生产羊肉发酵香肠,完全符合发酵肉制品对发酵剂的要求,并可使3种菌的优势得到互补,使发酵速度加快,提高营养价值。试验表明采用这3种菌生产发酵香肠是切实可行的。     

西班牙研究干腌发酵香肠中致使黑斑生成的腐败霉菌的鉴定及其特性

<正>腐败菌在肉制品贮藏过程中会对肉制品的品质产生较为不利的影响,为了研究干腌发酵香肠中致使黑斑生成的腐败微生物的特性,西班牙科学家从干腌发酵香肠上选取黑色斑点进行部分取样。根据不同培养条件下的形态学特征发现多数霉菌菌株初步鉴定为青霉菌,其中有一株芽枝霉菌。芽枝霉菌是唯一造成培养基变黑的菌株,可通过对ITS1-5.8S-ITS2r RNA和β-微管蛋白基因序列进一步鉴定。它还会在"salchichón"干腌发酵香肠的整个成熟过程中生成黑色斑点。另外,也建立了一种准确的实时荧光定量方法来检测香肠中致使生成黑色斑点的尖孢枝孢菌。这种方     

即食发酵肉制品熟化机制研究进展

即食发酵肉制品有着悠久的加工制作历史,因其营养丰富且具有独特的色泽和风味而深受消费者欢迎。迄今为止,未见即食发酵肉制品的熟化过程及其机制的全面综述。本文结合了近年来即食发酵肉制品相关研究进展,系统地阐述了其熟化过程中理化性质的变化,包括蛋白质和脂质的水解氧化、风味物质的形成以及质构的变化等。同时也总结了影响熟化的因素及其作用机制,包括酶的水解、发酵剂的抗氧化等以及腌制剂的呈味和增色的作用机制。最后讨论了现今研究存在的不足,并对未来的研究方向进行了展望,旨在为即食发酵肉制品的深入研究和发展提供理论依据。     

Prevalence of Salmonella spp. and Listeria monocytogenes at small-scale spanish factories producing traditional fermented sausages

The manufacturing of fermented sausages is subject to natural contamination processes that can potentially carry foodborne pathogens along the process chain and result in contamination of the final product. The aim of this study was to evaluate the occurrence of Salmonella spp. and Listeria monocytogenes at different sampling points during the manufacturing process of fuet, a type of traditional fermented sausage, at 10 small-scale Spanish factories. The presence of both pathogens was studied in the raw materials (19 casings and 19 meat batters), the final products (19 fermented sausages), and the factory equipment (12 mincing, 12 mixing, and 19 stuffing machines, 19 cutting tables, 11 knives, and 12 cold rooms) by using classical microbiological techniques and real-time PCR. Salmonella was not detected in the equipment analyzed or in the final products, but it was detected in the raw materials (23.7% of samples). L. monocytogenes showed higher incidence than Salmonella and was detected in the equipment (11.8% of samples), the raw materials (28.9%), and the final products (15.8%), confirming its ubiquity throughout the manufacturing process of fermented sausages. Five factories were further investigated to study the changes in the distribution of pathogens in the fuet production process over a period of either 2 or 3 years. There was considerable variation in the incidence of both pathogens at different sampling periods, and there was no relation between seasonal variations or geographic location of the factories.     

Sensory acceptability of slow fermented sausages based on fat content and ripening time

Low fat dry fermented sausages were manufactured using controlled ripening conditions and a slow fermented process. The effect of fat content and ripening time on the chemical, colour, texture parameters and sensory acceptability was studied. The fat reduction in slow fermented sausages produced an increase in the pH decline during the first stage of the process that was favoured by the higher water content of the low fat sausages. Fat reduction did not affect the external appearance and there was an absence of defects but lower fat content resulted in lower sausage lightness. The sausage texture in low fat sausages caused an increase in chewiness and at longer ripening times, an increase in hardness. The sensory acceptability of the fermented sausages analyzed by internal preference mapping depended on the different preference patterns of consumers. A group of consumers preferred sausages with high and medium fat content and high ripening time. The second group of consumers preferred sausages with low ripening time regardless of fat content except for the appearance, for which these consumers preferred sausages of high ripening time. Finally, the limit to produce high acceptability low fat fermented sausages was 16% fat content in the raw mixture that is half the usual content of dry fermented sausages.     

Meat starters have individual requirements for Mn(2+)

The effect of different Mn(2+) concentrations on sausage fermentation was evaluated. A screening experiment was carried out with six lactobacilli starters in a sausage model. To further investigate the effects found, two selected lactobacilli strains were tested in pilot-scale sausage production. For all starters an increased fermentation rate was observed after Mn(2+) addition. Differences in the development of microbial, textural and sensory parameters were observed in the sausages. For one of the cultures these differences levelled out during sausage production yielding identical end products with and without Mn(2+), for the other strain the differences due to Mn(2+) addition in the sausages remained throughout the production process yielding sausages with different properties. Knowing a starter culture's requirements for Mn(2+) will allow optimisation of dry fermented sausage production in order to increase reliability and reproducibility of production decrease fermentation time and ensure microbial safety of the final product.     

The effects of sodium lactate and starter cultures on pH, lactic acid bacteria, Listeria monocytogenes and Salmonella spp. levels in pure chicken dry fermented sausage

Two starter cultures (A and B) and seven sodium lactate concentrations were evaluated for chicken raw dry-fermented sausage processing. Starter culture B contained more lactic acid bacteria and less staphylococci than starter A. Their effects on acidification and inhibition of pathogens (Listeria monocytogenes and Salmonella spp.) were monitored. Starter culture B grew faster and was less inhibited by sodium lactate, thus inducting a faster and more important pH drop into the sausages. With lower pH, sausages processed with B starter were less contaminated by Listeria monocytogenes. The type of starter was found to influence the end-product pH, lactic acid bacteria content and extent of Listeria monocytogenes contamination. A 30-member panel did not note differences between sausages processed with the different starter cultures when lactate was added. Adding sodium lactate to the sausage mix reduced the pH drop in the dry sausage product. This acidification inhibiting effect of sodium lactate was greater for A. Sodium lactate significantly inhibited lactic acid bacteria development but did not reduce Listeria monocytogenes contamination frequency of the batches, unlike in many literature data. Sodium lactate may however control the acidification of the sausage processed with starter B, in order to obtain moderately acidified fermented sausages. A simple kinetic model was applied to our data. The sodium lactate content and especially the type of starter culture often had a significant effect on the four parameters of this empirical model (lag time, acidification time, initial and final pH).     

Release of aroma compounds from dry-fermented sausages as affected by antioxidant and saliva addition

The effect of the addition of an antioxidant and saliva on the release of aroma compounds from dry fermented sausages was studied by extracting the headspace at different times using solid phase micro-extraction technique. The compounds were analysed by gas chromatography using a FID detector and identified by mass spectrometry. The addition of butylated hydroxytoluene to dry fermented sausages produced a significant reduction of the release of most of the volatile compounds indicating an oxidation process during sampling. The addition of water and saliva to the dry fermented sausages produced a higher release of pentanal, hexanal and octanal, whilst pentane, 1-octanol, pentanoic acid, and propanal showed a lower rate of release. Moreover, phenylethyl alcohol, 2-butanone, 2,3-pentanedione and 2-nonanone, derived from bacterial metabolism, presented a lower release rate when water and saliva were added. The rate of release of the compounds from dry fermented sausages was not related with the compound hydrophobicity value. Further research is needed to elucidate the effect of fermented sausage matrix on the partitioning of the compounds and its effect on aroma perception.     

A fermented meat model system for studies of microbial aroma formation

A fermented meat model system was developed, by which microbial formation of volatiles could be examined. The model was evaluated against dry, fermented sausages with respect to microbial growth, pH and volatile profiles. Fast and slowly acidified sausages and models were produced using the starter cultures Pediococcus pentosaceus and Staphylococcus xylosus. Volatiles were collected and analysed by dynamic headspace sampling and GC-MS. The analysis was primarily focused on volatiles arising from amino acid degradation and a total of 24 compounds, of which 19 were quantified, were used for multivariate data analysis. Growth of lactic acid bacteria was comparable for model and sausages, whereas survival of S. xylosus was better in the model. Multivariate analysis of volatiles showed that differences between fast and slowly acidified samples were identical for model and sausage. For both sausage and model, fast-acidified samples had a high content of ketones, sulphides and methyl-branched acids, whereas slowly acidified samples had the highest content of methyl-branched alcohols, aldehydes, their ethyl esters, phenylacetaldehyde and methional. Furthermore, model repeatability with respect to pH, microbial growth and volatile profiles was similar to sausage production. Based on these findings, the model system was considered valid for studies of aroma formation of meat cultures for fermented sausage.     

Prevalence and antimicrobial susceptibility of Salmonella isolated from a variety of raw meat sausages in Gaborone (Botswana) retail stores

The objective of the study was to provide baseline data on the prevalence and antimicrobial susceptibility of Salmonella in different types of raw meat sausages directly accessible to the consumers in Gaborone, Botswana. A total of 300 raw sausages comprising 79 beef, 78 pork, 72 chicken, and 71 mutton samples were concurrently analyzed for the presence of Salmonella using a conventional culture method and a validated PCR method. The PCR assay results were in full concordance with those of the conventional culture method for the detection of Salmonella. Sixty-five (21.7%) of 300 samples were positive for Salmonella by both the conventional culture method and PCR assay. Even though more chicken samples contained Salmonella than did any other sausage type, the difference in the presence of Salmonella among the four sausages types was not significant. Eleven serotypes were identified, and Salmonella enterica subsp. salamae II was most prevalent in all the sausage types. Beef sausages generally had higher mesophilic bacterial counts than did the other three sausage types. However, higher microbial counts were not reflective of the presence of salmonellae. Susceptibility of the Salmonella enterica serotypes to 20 antimicrobial agents was determined, and Salmonella Muenchen was resistant to the widest array of agents and was mostly isolated from chicken sausages. Regardless of the meat of origin, all 65 Salmonella isolates were resistant to at least four antimicrobial agents: amikacin, gentamicin, cefuroxime, and tombramycin. This resistance profile group was the most common in all four sausage types, comprising 90% of all Salmonella isolates from beef, 71% from pork, 63% from mutton, and 35% from chicken. These results suggest that raw sausages pose a risk of transmitting multidrug-resistant Salmonella isolates to consumers.     

Effect of the fungal protease EPg222 on proteolysis and texture in the dry fermented sausage ‘salchichón’

Proteolytic activity of the fungal protease EPg222 and its effect on the texture of the dry fermented sausage ‘salchichón’, which has a long ripening process, was assayed. Samples with enzyme added showed a significant reduction of myofibrillar protein concentration during the ripening period, compared with a control, and proteolytic activity of the enzyme led to a higher accumulation of non‐protein and ‐amino acid nitrogen. Analysis of volatile compounds in ripened dry fermented sausages revealed that only in EPg222 batches were branched compounds derived from amino acids catabolism detected that are associated with the flavour of dry cured meat products. The texture profile analysis showed reduction in hardness, gumminess and chewiness values in treated compared with control sausages. The effect of this enzyme could be of great interest in stimulating proteolysis, in flavour development and in reducing the hardness of dry fermented sausages produced by a long ripening process. Copyright © 2004 Society of Chemical Industry     

Dry sausage fermented by Lactobacillus rhamnosus strains

The ability of three probiotic Lactobacillus rhamnosus strains GG, E-97800 and LC-705 and one commercial Pediococcus pentosaceus starter strain (control) to produce dry sausage was studied. During the fermentation process the numbers of inoculated lactic acid bacteria increased from approx. 7 log10 to 8-9 log10 cfu/g and the pH values decreased from 5.6 to 4.9-5.0. The sensory test indicated that the dry sausages fermented by L. rhamnosus LC-705 were inferior to the control sausages. The presence of inoculated experimental strains as predominant organisms in the dry sausages was recognised on the basis of their genetic fingerprints by ribotyping. The concentrations of biogenic amines remained low during the ripening process. These results indicated that the studied Lactobacillus rhamnosus strains, especially strains GG and E-97800, are suitable for use as probiotic starter cultures in fermenting dry sausage.     

Evaluation of Prerigor Freeze-Dried Beef in the Manufacture of Dry Fermented Sausage

Experiments were designed to determine the acceptability of prerigor freeze-dried beef in the manufacture of dry fermented sausage. Several chemical and physical variables were measured on dry fermented sausages prepared using (1) prerigor salted, freeze-dried, (2) prerigor unsalted, freeze-dried, (3) postrigor salted, freeze-dried, and (4) postrigor frozen beef as ingredients. Results showed that fat and moisture content, total shrinkage, Instron firmness and panel scores for juiciness, texture, and flavor were not affected to a large degree by treatment or rigor state of the beef ingredient. Generally, freezedried beef was found to be equal to conventional beef for dry sausage production regardless of when the freeze-dried beef was salted.