不同乳酸菌发酵剂对发酵红肠品质的影响

为研究乳酸菌发酵对红肠品质的影响,将发酵技术应用于本无发酵工艺的红肠制品中,筛选出能够提高红肠品质的乳酸菌发酵剂。分别将常应用于发酵肉制品的7 种商业乳酸菌发酵剂（木糖葡萄球菌＋戊糖片球菌（THM-17）、木糖葡萄球菌＋清酒乳杆菌＋类植物乳杆菌（PRO-MIX5）、木糖葡萄球菌＋肉葡萄球菌＋清酒乳杆菌（WBL-45）、木糖葡萄球菌＋戊糖片球菌＋植物乳杆菌（VHI-41）、木糖葡萄球菌＋戊糖片球菌＋植物乳杆菌（SHI-59）、肉葡萄球菌＋木糖葡萄球菌（WBX-43）和戊糖片球菌＋木糖葡萄球菌＋肉葡萄球菌＋乳酸片球菌（VBM-60））及8 种单菌（弯曲乳杆菌、戊糖乳杆菌、清酒乳杆菌-1、戊糖片球菌、木糖葡萄球菌、肉葡萄球菌、清酒乳杆菌-2、植物乳杆菌）以107 CFU/g的接种量接种至腌制后的肉馅中,拌馅灌肠后于35 ℃、80%湿度条件下发酵12 h,取样测定发酵后样品的乳酸菌数和细菌总数,再经干燥、蒸煮、烟熏、烘烤制得成品,测定其感官、pH值、色差、质构、亚硝酸盐、硝酸盐、生物胺及N-亚硝胺含量等指标。结果表明：15 种发酵剂中以木糖葡萄球菌和植物乳杆菌2 种乳酸菌发酵剂应用效果较好,所制得产品pH值分别为5.26和5.04,色泽美观,弹性适中,亚硝酸盐残留量（10.84、10.13 mg/kg）低,可显著抑制N-亚硝胺的形成（N-二甲基亚硝胺含量分别为1.29、2.51 μg/kg）,生物胺总量较低。由此说明,木糖葡萄球菌和植物乳杆菌能够显著提高红肠产品的安全品质。     

Charqui meats as fermented meat products: role of bacteria for some sensorial properties development

Jerked beef, a derivative of charqui meat, is a cured, salted and dried meat product. The presence of halotolerant bacteria, where Staphylococcus spp. (84.2%) were the predominant species, would act eventually as starter cultures and was followed throughout processing. Jerked beef prepared separately with exogenous S. carnosus and S. xylosus as starter cultures resulted in high proteolysis. Samples prepared with S. xylosus had the highest proteolysis and were preferred by the sensory panel. This research has suggested that jerked beef (and thus charqui meat) prepared under these conditions is a fermented meat product.     

Biochemical and sensory characteristics of traditional fermented sausages of Vallo di Diano (Southern Italy) as affected by the use of starter cultures

In this study, two strains of Staphylococcus xylosus isolated from traditional fermented sausages of Vallo di Diano (Southern Italy) were used in combination with an acidifying strain of Lactobacillus curvatus as starter culture for the production of fermented sausages. Two starter formulation were developed combining the proteolytic but not lipolytic (prt(+), lip(-)) S. xylosus CVS11 with the L. curvatus AVL3 (starter S1) and the S. xylosus FVS21 (prt(-), lip(+)) with the same strain of L. curvatus (starter S2). Proteolysis and lipolysis were observed during ripening by the increase in total free amino acids (FAA) and free fatty acids (FFA), respectively. Such activities were observed in both started and non started sausages (control). Moreover, the proteolytic and lipolytic activities were detected in products started by both formulations irrespective of the presence of such activities in the strains used. Therefore, it was not possible to conclude whether the effect of proteolysis and lipolysis during ripening of the started fermented sausages was due to the activity of the starter cultures or to the action of meat endogenous enzymes.     

Effects of starter cultures and nitrite levels on formation of biogenic amines in sucuk

The effects of starter cultures, starter A (Lactobacillus sakei+Staphylococcus carnosus) and starter B (Pediococcus acidilactici+Staphylococcus xylosus+Lactobacillus curvatus), nitrite levels (0, 75, and 150ppm) and ripening period on biogenic amine production were investigated in sucuk (Turkish dry-fermented sausage) production. Changes in biogenic amines, pH, water activity, moisture, non-protein nitrogen, nitrite and counts of lactic acid bacteria, Micrococcus/Staphylococcus, Enterobacteriaceae, and moulds-yeasts were determined. Ripening period had a very significant effect (P<0.01) on the all biogenic amines. Sausages produced by fermentation with starter cultures, as compared to natural fermentation (control), had lower amounts of putrescine, cadaverine and tyramine (P<0.05). Starter cultures A and B were found to have almost the same effect on the formation of biogenic amines. Use of nitrite in sucuk production affected the formation of biogenic amines except for spermidine and spermine (P<0.01). Lactic acid bacteria counts in the control group were lower than that of starter culture groups. Lactic acid bacteria, Micrococcus/Staphylococcus, and moulds-yeasts counts increased during ripening period while levels of species of Enterobacteriaceae decreased, which was also found to be under the detectable level (<100cfug(-1)), by day 3 of ripening.     

Effect of Commercial Starter Cultures on the Myofibrillar Proteins of Pastirma, a Turkish Dry Meat Product

ABSTRACT: The effect of 3 different commercial starter cultures ( Staphylococcus carnosus, Staphylococcus carnosus + Lactobocillus pentosus and Staphylococcus xylosus + Lactobacillus sakei ) on the myofibrillar proteins of pastirma was investigated. It was observed that using commercial starter cultures in pastirma manufacture had a significant effect on myofibrillar fragmentation. However, the effect of each starter culture on myofibrillar fragmentation in pastirma was different. Most of the changes in myofibrillar proteins were produced with S. carnosus + L. pentosus.     

Evaluation of different starter cultures (Staphylococci plus Lactic Acid Bacteria) in semi-ripened Salami stuffed in swine gut

The ripening properties were evaluated in semi-ripened pork Salami started by different cultures: CXP (Pediococcus pentosaceus, Staphylococcus xylosus and Staphylococcus carnosus); RAP (Lactobacillus plantarum, Lactobacillus sakei, S. xylosus and S. carnosus); and GY2 (L. sakei, S. xylosus and S. carnosus). These starters were chosen by their technological activities: CXP (rapid acidifying); RAP (medium acidifying); and GY2 (slow acidifying plus intense reddening-flavouring). Salami was enhanced with Ponceau 4R red and sodium glutamate, stuffed in pig gut and aged for 12 days at 15 °C/65-85%RH. Dehydration, reddening, proteolysis, fat acidity and lipid oxidation were hardly affected by the starters. Acidification by LAB strongly influenced the flavour. L. sakei plus L. plantarum provided a better flavouring than a low dose of L. sakei, and, especially, than over-acidifying P. pentosaceus. A final pH of 5 seems to be suitable for preventing aroma and taste defects in semi-ripened Salami. Spontaneous lactic microflora showed great acidifying potential.     

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.     

Characterization and technological properties of Staphylococcus xylosus strains isolated from a Tunisian traditional salted meat

The technological properties of strains of Staphylococcus xylosus were studied to select the most suitable for use as starter cultures for the production of dried fermented meat products. Strains of S. xylosus were isolated from traditional salted Tunisian meat and were identified by biochemical and molecular methods. Thirty strains of S. xylosus were studied to evaluate their catalase, nitrate reductase, lipolytic, proteolytic and antibacterial activities as well as growth ability at different temperatures, pH's and NaCl concentrations. All strains of S. xylosus had catalase activity and were able to reduce nitrates to nitrites. The nitrate reductase activity increased when the strains were kept under anaerobic conditions. Proteolytic activity on milk and on gelatin agar was demonstrated for 100% and 83.3% of the S. xylosus isolates, respectively. However extracellular proteolytic activity as assessed by the azocasein method was poor in all the strains. Lipolytic activity as assessed by the agar method showed that 76.6% of strains of S. xylosus could hydrolyze Tween 20 against 33.3% that could hydrolyze tributyrin. Tween 80 was hydrolyzed by only 10% of strains. Strains of S. xylosus hydrolyzed pork fat better than beef and lamb fat. The majority of strains had antibacterial activity against Salmonella arizonae, Staphylococcus aureus, Pseudomonas aeuroginosa, Escherichia coli and Enterococcus faecalis.     

Protein Degradation by Lactobacillus plantarum and Lactobacillus casei in a Sausage Model System

ABSTRACT: :
The proteolytic activity of a starter culture involving Lactobacillus plantarum and Lactobacillus casei towards meat sarcoplasmic and myofibrillar proteins during the fermentation of a sausage-like system was studied. After 96 h of incubation the proteolytic system of L. plantarum CRL681 caused a degradation of both sarcoplasmic and myofibrillar proteins, whereas L. casei CRL705 showed a different affinity to meat proteins. The inoculation of both strains showed a higher activity toward sarcoplasmic fraction. These results correlated with a high rate of sarcoplasmic protein degradation observed in SDS-PAGE analysis. The generation of free amino acids as well as the pH drop at the end of the incubation period was maximal in presence of the mixed starter culture, thereby demonstrating the suitability of these strains to be used in the fermentation of meat products.     

肉品混合发酵剂的筛选及应用研究

研究了戊糖片球菌(Pediococcuspentosaceus)P20、米酒乳杆菌(Lactobacillussake)J17分别同两株肉糖葡萄球菌(Staphylococcuscarnosus)S15和S113在模拟肉汤培养基中混合培养的相互关系,初步筛选出没有拮抗作用的混合发酵剂P20 S15应用于发酵香肠,测定并分析了发酵和成熟过程中理化和微生物指标的变化,认为可以作为混合发酵剂用于香肠的生产。     

木糖葡萄球菌和肉糖葡萄球菌的生理特性及其转化硝酸盐影响因素的研究

对普遍存在于发酵肉制品中具有硝酸还原酶活性的2种外源性木糖葡萄球菌和肉糖葡萄球菌的生理生化特性进行了鉴定,并研究了不同温度、pH、盐含量对两菌株及不同混合配比菌株生成亚硝酸盐量的影响。结果表明:两菌株均具有较强的耐盐性、耐亚硝性、耐硝酸盐性,且在30、40℃,pH6.5,2%NaCl时生成亚硝酸盐速率最快。生理生化等鉴定实验表明,木糖葡萄球菌和肉糖葡萄球菌可为发酵肉制品生产中的优良菌株选择和应用提供理论参考。     

发酵风干肠中乳酸菌的发酵性能

对从自然发酵风干肠中分离的6 株乳酸菌的发酵性能进行评价,主要包括测定菌株的生长曲线、产酸能力、对NaCl及NaNO2的耐受能力,同时通过吲哚实验和抗生素敏感性测定对菌株的安全性进行初步评价。结果表明：6 株乳酸菌生长趋势接近,均在8 h左右进入生长稳定期,pH值在0～8 h下降最快,清酒乳杆菌和发酵乳杆菌的产酸能力更强;所有菌株均可在6 g/100 mL NaCl和0.015 g/100 mL NaNO2条件下生长,植物乳杆菌和弯曲乳杆菌的NaCl耐受能力最优,清酒乳杆菌和发酵乳杆菌则对NaNO2具有最强的耐受能力;吲哚实验中6 株乳酸菌的反应结果均为阴性,对实验所选抗生素无耐药性,说明6 株乳酸菌具有较好的发酵性能和安全性,可作为功能性发酵剂用于发酵肉制品的生产。     

Starters in the processing of meat products

Starter cultures applied in meat technology may contain moulds, yeasts and bacteria. Moulds have been selected with the primary intension to exclude any potential of mycotoxin production. Their sensory effects and the requirements of technology are also criteria for suitable starters. Their genetic potential can now be modified by genetic engineering. Yeasts are applied for sensory reasons mainly. The species in use are only fermentative and do not enhance nitrate reduction. Bacterial components of starters consist of micrococci, staphylococci, lactic acid bacteria (LAB) and, with minor importance, Streptomyces griseus or Aeromonas sp. For selection of the appropriate organisms and for ensuring optimum performance in the fermentation process, their technological, ecological, physiological and genetic properties should be well known. Most knowledge is available for LAB, which represent the most important group of starter organisms, since they are involve in the fermentation of all types of products and contribute to each single aim of the fermentation process. The study of the properties of the organisms may also contribute to reduction of potential hygienic risks not only in the classical fields of starter application but also in new fields where they may be employed as protective cultures that inhibit the growth of food pathogens or even spoilage organisms. Strains with an improved potential to reduce these risks and to exhibit further useful properties can be obtained by means of genetic engineering. Examples for successfully modified meat specific bacteria are Staphylococcus carnosus and lactobacilli L. curvatus and L. sake.     

Interactions of meat-associated bacteriocin-producing Lactobacilli with Listeria innocua under stringent sausage fermentation conditions

The kinetics of the antilisterial effect of meat-associated lactobacilli on Listeria innocua LMG 13568 were investigated during laboratory batch fermentations. During these fermentations, which were performed in a liquid meat simulation medium, a combination of process factors typical for European-style sausage fermentations was applied, such as a temperature of 20 degrees C and a representative pH and salting profile. Two bacteriocin-producing sausage isolates (Lactobacillus sakei CTC 494 and Lactobacillus curvatus LTH 1174), which have already proven efficacy in sausage trials, and one nonbacteriocinogenic, industrial strain (Lactobacillus sakei I), were evaluated. Staphylococcus carnosus 833 was included in the experiment because of its role in flavor and color development. When grown as a monoculture or upon cocultivation with L. sakei I and S. carnosus 833, L. innocua LMG 13568 developed slightly, despite the stress of low temperature, pH, lactic acid, salt, and nitrite. In contrast, when either of the bacteriocin producers was used, the L. innocua LMG 13568 population was rapidly inactivated with more than 3 log CFU ml(-1) after 2 days of fermentation. A bacteriocin-tolerant L. innocua LMG 13568 subpopulation (4 X 10(-4)) remained after bacteriocin inactivation. Thus, when the initial level of L. innocua LMG 13568 equaled 3 log CFU ml(-1), all cells were inactivated and no bacteriocin-tolerant cells were detected, even after 7 days of incubation. S. carnosus was not inactivated by the Lactobacillus bacteriocins and displayed slight growth.     

The influence of manufacturing and drying conditions on the survival and toxinogenesis of Staphylococcus aureus in two Spanish dry sausages (chorizo and salchichón)

The effects of formulation, starter culture and fermentation temperature on growth and synthesis of toxin A (SEA) and TNase by Staphylococcus aureus during fermentation and drying of Spanish chorizo were investigated. Inhibitory factors able to inhibit SEA synthesis in culture media were unable to prevent SEA production in chorizo fermented at 20 and 30°C, though a lower temperature and starter culture SP318 (Lactobacillus sake, Pediococcus pentosaceous and Staphylococcus xylosus) decreased staphylococcal growth and SEA formation. Reduction and even disappearance of the SEA during ripening was observed. In most batches, TNase was a reliable indicator of staphylococcal growth and SEA production. Dextrose added to the salchichón formulation repressed S. aureus growth during drying. Lactobacillus curvatus in combination with dextrose was an effective anti-staphylococcal agent during fermentation.     

发酵牛肉干加工中理化特性与风味品质分析

为探究发酵牛肉干不同加工阶段理化性质和风味品质的变化,以牛臀肉为原料,接种木糖葡萄球菌和清酒乳杆菌制作发酵牛肉干,并对牛肉干在发酵前后及成品的营养成分、质构、色泽等理化特性及游离氨基酸、脂肪酸组成和挥发性风味物质对比分析。结果表明,与发酵前相比,接种复合发酵剂的牛肉干pH值、水分活度、亚硝酸盐残留量、硬度、咀嚼性均显著降低（P＜0.05）;红度值和游离氨基酸含量显著增加,且鲜味氨基酸占比最高;游离脂肪酸以棕榈酸、硬脂酸、油酸、亚油酸为主,其中油酸占比最大;发酵后牛肉检出47 种挥发性化合物,高于发酵前42 种,提高了牛肉干中醛、醇、酚、酯、酸、含氮及其他化合物的种类和相对含量。发酵牛肉干质构及色泽明显改善,游离氨基酸和脂肪酸含量增加,产品营养价值、风味品质及质量安全显著提高。     

Identification of lactic acid bacteria isolated from kimchi and studies on their suitability for application as starter culture in the production of fermented sausages

The aim of the investigation was to identify strains of lactobacilli coming from kimchi with properties suitable for use as starter cultures in sausage fermentation. A total of 31 strains of lactobacilli were isolated from kimchi on the 4-6th day of fermentation at 20°C using MRS agar plates and identified on the basis of morphological, biochemical, and physiological characteristics. The isolates were identified as Leuconostoc mes.mes./dent (12.9%), Lactobacillus curvatus (9.7%), Lactobacillus brevis (35.5%), Lactobacillus sake (25.8%), and Lactobacillus plantarum (16.1%). Thus, 51.6% of the isolates were homo-fermentative or facultative hetero-fermentative bacteria and the rest (48.4%) were hetero-fermentative bacteria. Among them L. brevis, L. curvatus, L. plantarum, and L. sake were investigated for their growth profile and metabolism characteristics in the fluid (submerged) model-medium modified according to the special conditions of fermented sausages. Relatively good growth properties were found for L. brevis, L. plantarum, and L. sake with maximum numbers of 8.18, 8.51 and 8.17cfu/ml, respectively, whereas L. curvatus could not adapt to the special environmental conditions. Regarding souring properties, L. brevis showed little ability to decrease pH, whereas L. curvatus, L. plantarum, and L. sake showed relatively good acidifying properties. According to the results of glucose fermentation and its products, only L. plantarum exhibited homo-fermentative characteristics. As a result only L. plantarum among the isolates from kimchi had an ability to adapt to the complex environment of fermented sausage, which will thereby allow them to act as starter cultures and natural preservatives in sausage production.     

木糖葡萄球菌添加量对发酵牛肉串品质特性的影响

研究木糖葡萄球菌的添加量对发酵牛肉串理化性质和感官特性的影响。将不同添加量的木糖葡萄球菌分别与干酪乳杆菌(107CFU/g)复配作为发酵剂用于生产发酵牛肉串,测定发酵牛肉串在发酵成熟过程中的pH值、水分活度、颜色、质构及感官指标的变化。结果表明：添加108CFU/g木糖葡萄球菌的发酵肉串气味值最高(4.75±0.38),但木糖葡萄球菌菌种添加量为106、108CFU/g时,发酵肉串的色泽、质地、总体可接受性均低于木糖葡萄球菌菌种添加量为107CFU/g的肉串;而原料肉中添加107CFU/g木糖葡萄球菌的实验组在发酵终点时产品获得优良的感官特性(总体可接受性达到最高值5.31),pH值达到5.4,质构特性好,并与其他实验组存在显著性差异(P≤0.05)。     

Lactobacillus role during conditioning of refrigerated and vacuum-packaged Argentinean meat

The role of Lactobacillus strains with bioprotective and technological potential on raw beef during 15days of storage under vacuum at 7°C was investigated. The assayed strains were able to grow on the meat, Lactobacillus curvatus CRL705 and Lactobacillus sakei 23K showing the highest competitiveness. A net increase of amino acids was determined in inoculated samples when compared to the control, this being maximal for Lactobacillus plantarum CRL681. Although an important endogenous activity of meat sarcoplasmic proteins was observed, the disappearance of protein bands and the generation of a new one were detected as a consequence of Lactobacillus growth. A synergistic effect of Lactobacillus in combination with the muscle proteolytic enzyme complex can be suggested. From the studied strains, the bacteriocin producer L. curvatus CRL705 may be considered as a good candidate to contribute to meat ageing by means of small peptides and free amino acids generation while improving shelf life.     

复合菌株发酵对鱼露中生物胺含量的影响

文中研究了以米曲霉为种曲发酵鱼露的工艺,在此基础上,接人木糖葡萄球菌、植物乳杆菌及其复合菌株共同发酵,分析了单一菌株和复合菌株对鱼露中生物胺(组胺、腐胺、酪胺、亚精胺)生成量的影响.结果表明,单一的木糖葡萄球菌及其与植物乳杆菌的复合菌株都可以降低鱼露中生物胺的含量,其中,在米曲霉生长的稳定期时接入复合菌株时效果最好,与对照组相比总胺降低了61.9%.