Role of an autochthonous starter culture and the protease EPg222 on the sensory and safety properties of a traditional Iberian dry-fermented sausage "salchichón"

The effect of the addition of an autochthonous starter culture and the protease EPg222 on the physico-chemical and sensory characteristics of dry-fermented sausage ‘‘salchichon” was investigated. Sausages were prepared with purified EPg222 and Pediococcus acidilactici MS200 and Staphylococcus vitulus RS34 as starter culture (P200S34), separately and together, ripened for 90 days, and compared with a control batch. Dry-fermented sausages ripened with EPg222 and starter culture showed higher amounts of AN and volatile compounds derived from amino acid catabolism than the control, especially in samples in which was added the association of enzyme and starter culture (P200S34 + EPg222). There were clear differences shown by the texture analysis, with the P200S34 + EPg222 batch being less hard. Especially important was the result found in biogenic amines, since the association P200S34 + EPg222 reduced their accumulation compared to the EPg222 batch. The use of EPg222 may be of great interest to improve the sensory characteristics of dry-fermented sausages, but its association with the selected starter culture with low decarboxylase activity is necessary to guarantee healthiness and homogeneity.     

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     

Comparison of the effects of a commercial and an autochthonous Pediococcus acidilactici and Staphylococcus vitulus starter culture on the sensory and safety properties of a traditional Iberian dry‐fermented sausage “salchichón”

The effect of the addition of an autochthonous starter culture and commercial starter culture on the physico‐chemical and sensory characteristics of the dry‐fermented sausage ‘salchichon’ was investigated. Sausages were prepared with a mixture of Pediococcus acidilactici MC184 and Staphylococcus vitulus RS34 as the autochthonous starter culture (P184S34), ripened for 86 days, and compared with a commercial starter batch (CS1). Strains of acid lactic bacteria and Staphylococcus were identified in the samples along the ripening process which demonstrated that the inoculation of sausages assures their implantation during the ripening process. However, P184S34 starter culture showed a higher inhibitory effect on enterobacteria and coliform flora than the CS1 batches, guaranteeing a better quality hygienic sausages. Dry‐fermented sausages ripened with P184S34 showed higher amounts of NPN and volatile compounds derived from amino acid catabolism than the CS1 batches. Especially important was the result found in biogenic amines, since the P184S34 reduced their accumulation compared to the commercial starter batch. The inoculation of a decarboxylase‐negative autochthonous starter culture P184S34 reduced the biogenic amine accumulation guaranteeing safety and homogeneity of the products without producing a negative effect on the sensory characteristics of the traditional fermented sausages.     

Use of autochthonous Pediococcus acidilactici and Staphylococcus vitulus starter cultures in the production of "chorizo" in 2 different traditional industries

The present study determined how the different ripening conditions affected the growth and development of 3 autochthonous starter cultures, and the physico-chemical and sensory characteristics of chorizo. Each of 3 strains of Pediococcus acidilactici (MC184, MS198, and MS200) and one of Staphylococcus vitulus (RS34) were associated to prepare the starter cultures, P184S34, P198S34, and P200S34. Then, chorizo was prepared following 2 manufacturing procedures. The autochthonous starter cultures were able to compete and colonize the sausages in both ripening procedures. The use of the starter cultures showed evident differences by the texture analysis, with the control batches being generally tougher than the starter culture batches. Also, the highest biogenic amine (BA) levels were found in control batches and the lowest in P200S34 batches. While the use of these starter cultures does not change the sensory characteristics of these traditional fermented sausages, it improves their homogeneity and safety, except for P184S34 batch in which more BAs are detected in industry 2. PRACTICAL APPLICATION: The 3 autochthonous starter cultures selected could be used in traditional industries because they are able to compete well and colonize the dry fermented sausages "chorizo." The use of these starter cultures improves the texture and homogeneity of traditional fermented sausages. Biogenic amines decreased in the starter cultures batches improving the safety.     

Safety improvement and preservation of typical sensory qualities of traditional dry fermented sausages using autochthonous starter cultures

Traditional dry fermented sausages are manufactured without addition of starter cultures in small-scale processing units, their fermentation relying on indigenous microflora. Characterisation and control of these specific bacteria are essential for the sensory quality and the safety of the sausages. The aim of this study was to develop an autochthonous starter culture that improves safety while preserving the typical sensory characteristics of traditional sausages. An autochthonous starter composed of Lactobacillus sakei, Staphylococcus equorum and Staphylococcus succinus isolated from a traditional fermented sausage was developed. These strains were tested for their susceptibility to antibiotics and their production of biogenic amines. This starter was evaluated in situ at the French traditional processing unit where the strains had been isolated. Effects of the autochthonous starter were assessed by analysing the microbial, physico-chemical, biochemical and sensory characteristics of the sausages. Inoculation with the chosen species was confirmed using known species-specific PCR assays for L. sakei and S. equorum and a species-specific PCR assay developed in this study for S. succinus. Strains were monitored by pulse-field gel electrophoresis typing. Addition of autochthonous microbial starter cultures improved safety compared with the traditional natural fermentation of sausages, by inhibiting the pathogen Listeria monocytogenes, decreasing the level of biogenic amines and by limiting fatty acid and cholesterol oxidation. Moreover, autochthonous starter did not affect the typical sensory quality of the traditional sausages. This is the first time to our knowledge that selection, development and validation in situ of autochthonous starter cultures have been carried out, and also the first time that S. equorum together with S. succinus have been used as starter cultures for meat fermentation. Use of autochthonous starter cultures is an effective tool for limiting the formation of unsafe compounds in traditional sausage while preserving their original and specific sensory quality.     

Proteolytic and lipolytic starter cultures and their effect on traditional fermented sausages ripening and sensory traits

In this study, three starter formulations including Lactobacillus curvatus and Staphylococcus xylosus strains selected in vitro on the basis of their lipolytic and proteolytic activities were employed for the manufacture of traditional fermented sausages of southern Italy. Microbial population, proteolysis, lipolysis, changes in free amino acids (FAA) and free fatty acids (FFA) and development of characteristic taste and flavor of the final product were investigated. Proteolysis and lipolysis were observed in sausages inoculated with proteolytic and lipolytic S. xylosus coupled with L. curvatus, while the sausage started with only S. xylosus without lactobacilli was identical to the non-inoculated control, indicating that the proteolysis could be due to both microbial activity and endogenous proteases activated by the decrease in pH. The statistical analysis applied to the instrumental and sensory data showed that there was an effect of the starter used on the characteristics of the sausage obtained. In particular, the control samples showed very close features different from the sausages obtained by adding starter cultures. Finally, analyzing the sensory parameters the sausages ripened without starter addition and those started without the L. curvatus AVL3 showed similar features indicating an influence of the presence of the lactobacilli on the final organoleptic quality of the sausages. An appropriate choice of a combination of strains in a starter formulation is fundamental to obtain products of the expected quality.     

Effect of proteolytic starter cultures of Staphylococcus spp. on biogenic amine formation during the ripening of dry fermented sausages

The effect of proteolytic starter cultures of Staphylococcus carnosus and Staphylococcus xylosus on biogenic amine production was examined during the fermentation process of dry sausages. Microbial counts (lactic acid bacteria, Micrococcaceae and Enterobactenaceae), pH, moisture and proteolysis-related parameters were also studied. The polyamines spermine and spermidine were the main amines found in the raw material and they only showed slight fluctuations during the fermentation. The four elaborated batches presented a significant (P < 0.001) formation of tyramine and putrescine. The main rate of amine production was during the first three days, when a sharp pH decrease and the development of lactic acid bacteria occurred. Sausages fermented with starters had lower amounts of tyramine than naturally fermented sausages (control), but differences in the Micrococcaceae counts were only significant during the first week of the ripening process. A slight formation of diaminopropane, cadaverine, agmatine, tryptamine and phenylethylamine was observed. The amounts of histamine were constant and remained below 0.5 mg/kg of dry matter, while serotonin, octopamine and dopamine were not detected. The sausages with Staphylococcus as starter culture showed strong proteolysis that was correlated with higher pH values than those of the control sausages. However, no positive correlation was found between the proteolysis index and biogenic amine production. Since proteolysis was stronger during the second half of the ripening process, the release of free amino acids as amine precursors occurred later than the early amine production.     

Changes in selected biochemical and sensory parameters as affected by the superficial inoculation of Penicillium camemberti on dry fermented sausages

An atoxigenic strain of Penicillium camemberti was superficially inoculated on fermented sausages in an attempt to improve their sensory properties. The growth of this mould on the surface of the sausages resulted in an intense proteolysis and lipolysis, which caused an increase in the concentration of free amino acids, free fatty acids (FFA) and volatile compounds. Many of these were derived from amino acid catabolism and were responsible for the "ripened flavour", i.e. branched aldehydes and the corresponding alcohols, acids and esters. The development of the fungal mycelia on the surface of the sausages also protected lipids from oxidation, resulting in both lower 2-thiobarbituric acid (TBARS) values and lipid oxidation-derived compounds, such as aliphatic aldehydes and alcohols. The sensory analysis of superficially inoculated sausages showed clear improvements in odour and flavour and, as a consequence, in the overall quality of the sausages. Therefore, this strain is proposed as a potential starter culture for dry fermented sausage production.     

腌腊肉制品中乳酸菌的筛选鉴定及其在腊肠中的应用

为筛选适合传统腌腊肉制品的优良乳酸菌菌株,从多种农家自制传统腌腊肉制品中分离纯化出9株优势乳酸菌。通过发酵特性筛选,得到一株性状优良菌株10M-7,并制备该菌株的干粉发酵剂,以未接种发酵剂腊肠为对照,分析此发酵剂对腊肠感官品质和微生物变化的影响。结果表明,10M-7菌株具有良好的产酸特性和抑菌性能。根据形态学、生理生化特征和16S rRNA序列分析,鉴定其为植物乳杆菌,采用冷冻干燥法制备纯种发酵剂,并制作人工发酵腊肠。发酵剂组pH值在初期便迅速下降,且始终低于对照组;发酵剂组乳酸菌迅速生长繁殖,且葡萄球菌和大肠杆菌数量与对照组相比明显降低。感官评价表明,当添加量为10~4CFU/g原料肉时,能够很好地保持和改善产品风味,使产品整体感觉更好。     

接种乳酸菌发酵剂对风干肠成熟过程中微生物群落动态变化及感官品质的影响

为研究乳酸菌发酵剂对风干肠成熟过程中微生物数量、微生物多样性及感官品质的影响,分别将SHI-59(木糖葡萄球菌+戊糖片球菌+植物乳杆菌)、WBL-45(木糖葡萄球菌+肉葡萄球菌+清酒乳杆菌)、PRO-MIX5(木糖葡萄球菌+清酒乳杆菌+类植物乳杆菌)复合型商业发酵剂接种到肉馅中,经过12?d的成熟过程生产发酵型风干肠,...     

A newly isolated strain Pediococcus parvulus from Xuanwei ham, a traditional Chinese fermented meat product

A comparative study on technological suitability for fermented dry sausages of Pediococcus parvulus , a newly isolated strain from Xuanwei ham, a traditional Chinese fermented meat product, was carried out. One type of fermented dry sausage was produced with P. parvulus and the other without starter culture, using the same formulation and technological conditions. Thus, the evolutions of microbiological and physicochemical parameters during ripening, as well as colour, texture and sensory quality of end products, were measured and assessed. The results indicated that P. parvulus had an inhibitory effect on non-lactic acid bacteria, especially Enterobacteriaceae . It was thought that the use of P. parvulus could enhance the hygienic quality of fermented sausages, which could mainly be attributed to its acidification of fermented sausages. Differences in colour parameters, with higher value in lightness (L*) and lower in redness (a*), were also found ( P  < 0.05). The most significant differences were observed in texture, informing the influence of P. parvulus on texture profile analysis characteristics of fermented sausages ( P  < 0.05). However, the evolutions of total nitrogen, fat and ash were the same. That meant the starter had no effects on these parameters during ripening of sausages. Free amino acid analysis showed that P. parvulus might have some proteolytic activity and more intense odour detected by our sensory judges. Our panelists also gave a higher score to the sausage with starter in terms of overall acceptability, indicating their preference of this product to the control. For all these results, we concluded that the newly isolated strain P. parvulus was a good starter for the production of fermented sausages.     

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.     

发酵剂对发酵香肠食用品质的影响及其在不同直径香肠中的应用

以商业发酵剂（木糖葡萄球菌＋戊糖片球菌）为对照组,不同发酵剂组合（木糖葡萄球菌＋副干酪乳杆菌、木糖葡萄球菌＋戊糖片球菌＋副干酪乳杆菌）为实验组,通过对发酵香肠水分含量、pH值、水分活度、色泽、质地、风味和感官品质等指标进行测定,确定最佳发酵剂及适宜发酵的香肠直径。结果表明：相较于商业发酵剂,木糖葡萄球菌与副干酪乳杆菌组合发酵的香肠总体可接受性相对较高,且庚醛、1-辛烯-3-醇、乳酸乙酯、戊酸乙酯、癸酸乙酯、2-甲基丙酸乙酯等愉悦风味物质为该组独有,其特征主要表现为更加浓郁的清新味、甜香味、果香味和花香味;适宜的直径（21 mm）、水分含量（（25.40±0.00）%）和硬度（（2 812.46±767.93）g）以及相对较高的pH值（pH 5.57±0.02）是该组发酵香肠口感显著高于其他2 组的重要原因。因此,木糖葡萄球菌与副干酪乳杆菌组合发酵的小直径香肠食用品质最佳。     

复合发酵剂和天然香辛料对羊肉发酵香肠品质特性的影响

通过接种复合发酵剂和添加天然香辛料,采用相同的工艺条件生产4组羊肉发酵香肠,1组为对照组,2组为接种发酵剂组,3组为发酵剂+黑胡椒组,4组为发酵剂+黑胡椒+孜然组。分别测定4个组羊肉发酵香肠在发酵成熟和贮藏过程中pH值、Aw值、水分含量及微生物的变化。结果表明:在发酵结束(即第1.5天)时,试验组和对照组的pH值、Aw值和水分含量均呈下降趋势,试验组的pH值迅速降到最低值(即5.0以下),与对照组差异显著(P<0.05);在干燥成熟过程中,试验组的pH值、Aw值和水分含量迅速下降,添加香辛料组的pH值迅速回升,同时乳酸菌数维持在108cfu/g以上水平,高于对照组,细菌总数却低于对照组;在贮藏过程中,试验组的pH值和水分含量基本保持不变,且均低于对照组,而Aw值始终呈下降趋势,细菌总数小于对照组。上述结果表明,接种复合发酵剂和添加天然香辛料能迅速降低pH值、Aw值和水分含量,有效抑制腐败菌和致病菌的生长,提高羊肉发酵香肠的品质和保藏性。     

Dry fermented sausages of Southern Italy: a comparison of free amino acids and biogenic amines between industrial and homemade products

This paper compares some important parameters and the free amino acid and biogenic amine contents of cured industrial and homemade meat products. To this aim, industrial and homemade "soppressata" and "salsiccia", typical dry fermented sausages produced in Southern Italy, were analyzed. The homemade sausages showed a higher level of free biogenic amines than that manufactured industrially, most likely because biogenic amine formation in industrial products is limited by the use of starter cultures. The industrial sausages are characterized by a higher total free amino acid content than the homemade products. Overall, free amino acid and biogenic amine contents demonstrated that appreciable differences exist between homemade and industrial sausages.     

商业发酵剂对发酵香肠成熟过程中理化性质的影响

采用SBM-52、SHI-59、VBM-60复合型商业发酵剂生产发酵香肠,以不添加发酵剂作为对照组,在成熟第0、1、4、7、10天检测4 组香肠的pH值、非蛋白氮（non-protein nitrogen,NPN）含量、酸价、亚硝酸盐含量、水分活度（water activity,aw）、色差等理化指标的变化,考察不同商业发酵剂对发酵香肠成熟过程中理化品质的影响。结果表明：成熟终点时,4 组发酵香肠的pH值均小于5.0,亚硝酸盐含量低于30 mg/kg,充分保证了发酵香肠的安全性;NPN含量、aw和失重率的测定结果表明,添加3 种商业发酵剂均有助于发酵香肠中蛋白质的分解,加快成熟进程;SBM-52和VBM-60组香肠的酸价低于对照组,表明SBM-52和VBM-60具有较好的抑制脂肪氧化的作用。     

Nonprotein Nitrogen (NPN) and Free amino acid contents of dry, fermented and nonfermented sausages

Fermented and nonfermented sausages were analyzed for concentration changes in total and nonprotein nitrogen (NPN) and in free amino acid profiles during processing. Sausages fermented by Pediococcus pentaceous at 38°C and heated to 60°C had increases (p < 0·05) in total N and NPN contents and increases in concentration (≥5 mg per 100 g dry sample) for 14 of 20 free amino acids. Nonfermented sausages had no increase (p > 0·05) of NPN content and increases in only 6 of 20 free amino acids after heating to 60°C. When the effects of three starter cultures were compared, NPN concentrations after fermentation and heating and after drying were highest to lowest in the following order: P. pentaceous >P. acidilactici with M. varians >P. acidilactici. Variations of free amino acid patterns in the fermented, dried sausages were found which indicated differences in metabolic activity between the cultures. These variations did not (p > 0·05) affect sensory scores for the dried sausages. Overall, these results for rapidly fermented and mildly heated dry sausages were similar to results previously reported for 'European-style' dry sausages processed with prolonged low temperature fermentations.     

Use of Fourier transform infrared spectroscopy to evaluate the proteolytic activity of Yarrowia lipolytica and its contribution to cheese ripening

The interaction between tyrosine-decarboxylase and proteolytic activities of a Lactobacillus curvatus and Staphylococcus xylosus, respectively, on biogenic amine production during the ripening and the storage of dry fermented sausages was investigated. Water content, pH, proteolysis parameters, microbial counts, and biogenic amine contents were monitored in spontaneously and starter fermented sausages. The use of proteolytic staphylococci as starter resulted in a higher content of non-protein nitrogen and total free amino acids. Tyramine was the main amine produced in all batches. However, tyrosine-decarboxylase activity of the L. curvatus starter strain was weak and yielded lower amounts of tyramine than those produced by the wild mioroflora in the control batch. Association between tyramine production and proteolysis could only be established in a defectively dried batch. Putrescine and cadaverine accumulation was efficiently reduced in the starter-mediated fermentation, in agreement with the lower development of enterobacteria. Phenylethylamine and tryptamine were only detected in the spontaneously fermented sausages, while histamine, spermine and spermidine did not vary during the ripening. Biogenic amine levels and related parameters showed significant changes during the storage of dry sausages depending on the temperature and the batch. As a general rule, changes in the pH, proteolysis, microbial counts, and biogenic amine contents were stronger at 19 degrees C than at 4 degrees C. The results suggest that refrigeration would be advisable for preventing further accumulation of biogenic amines during the storage of dry fermented sausages.     

Microbiological and sensory quality of dry fermented sausages containing alginate-microencapsulated Lactobacillus reuteri

The probiotic bacterium Lactobacillus reuteri was added to dry sausage batter, without or after being microencapsulated in alginate using either extrusion or emulsion technology. Pediococcus pentosaceus and Staphylococcus carnosus were added at 7 log cfu/g as starter cultures for fermentation. The sausage batter was stuffed in 55 mm fibrous casings and fermented, with smoking, at 相似文献   

低盐发酵香肠用优良菌株的分离筛选及鉴定

从10 种我国自然发酵制品中分离纯化得到52 株乳酸菌及56 株过氧化氢酶阳性球菌,首先通过菌株耐受性、发酵特性等指标对菌株进行初步筛选,然后利用抑菌特性和风味特性对菌株进行复筛,选择可能改善低盐发酵香肠安全性和风味的优良菌株,最终筛选得到3 株葡萄球菌Z9、L2和R2,以及4 株乳酸菌P6、P12、X和SN1-3。经由形态学特征、生理生化特征及16S rDNA序列分析对筛选得到的菌株进行鉴定,结果表明,葡萄球菌菌株Z9、L2为腐生葡萄球菌,R2为肉葡萄球菌;乳酸菌菌株P6、P12均为植物乳杆菌,X为干酪乳杆菌,SN1-3为戊糖片球菌。最后测定菌株的生长特性及产酸能力,研究菌株间的拮抗特性,最终筛选得到戊糖片球菌SN1-3与肉葡萄球菌R2作为制作发酵香肠的复配菌株。