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。     

新型发酵兔肉的研究

通过比较植物乳杆菌(Lactobacillus plantarum，简称Lp)，干酪乳杆菌(Lactobacillus casei，简称Lc)、乳酸乳杆菌(Lactobacillus lactis，简称Ll)、乳酸链球菌(Streptococcus lactis，简称S1)、短乳杆菌(Lactobacillus brevis，简称Lb)等5株乳酸菌在兔肉汁培养基中的产酸性，筛选出产酸能力较强的Ll、Lc作为发酵菌株，对兔肉进行双菌株混合发酵。试验结果表明：发酵16-20h，产品质量较好；发酵结束后，产品经加热处理，风味更佳。     

分离自传统发酵乳制品中具有优良发酵特性的保加利亚乳杆菌的筛选

以分离自传统发酵乳制品中的11株德氏乳杆菌保加利亚亚种(Lactobacillus delbeueckii subsp.bulgaricus)为研究对象,通过全脂乳单菌发酵,对其发酵乳的发酵时间、pH值、滴定酸度、乙醛和双乙酰含量等指标进行分析,最终筛选出1株具有优良发酵特性的菌株IMAU20775。该菌株发酵时间较短,后酸化能力弱,产乙醛能力较好,产双乙酰能力较稳定,适于进一步作为发酵剂菌种的筛选和应用研究。     

混合菌种发酵羊肉香肠理化性质的初探

选择可生产发酵肉制品的植物乳杆菌、弯曲乳杆菌、乳酸片球菌发酵剂制作羊肉发酵香肠。研究3个菌种混合下发酵羊肉香肠的理化性质。结果表明:实验组相比对照组(单一菌种发酵)的亚硝酸盐的残留量、TBA值和TVB-N值明显降低了。     

酸驼乳发酵乳酸菌菌株的筛选及其发酵特性研究

对新疆自然发酵骆驼乳中乳酸菌菌群进行分离鉴定得到五株乳酸菌,其中乳杆菌3株分别为瑞士乳杆菌(Lactobacillus helveticus)、植物乳杆菌(Lactobacillus plantrum)和开菲尔乳杆菌(Lactobacillus kefiri),片球菌2株分别为乳酸片球菌(Pediococcus acidilactici)戊糖片球菌(Pediococcus pentosaceus)。分离鉴定出的五株乳酸菌在培养基中生长良好,其活菌数在培养16 h后能达到109 CFU/m L。将传统酸奶发酵剂接种于骆驼乳中并于42℃条件下培养,发现其在骆驼乳中能较好地产酸,其添加量在0.1%时最适。将筛选到的乳酸菌制备成生产发酵剂与传统酸奶发酵剂复配,得到瑞士乳杆菌组的复配效果最佳,具有最优的产酸效果,在经过6 h发酵后p H值降到4.5左右,酸度达到85oT,且制备的发酵骆驼乳具有最好的感官品质,其感官评分明显高于其他菌株复配进行发酵的骆驼乳产品。因此,可将0.1%传统酸奶发酵剂与筛选到的瑞士乳杆菌制备的生产发酵剂复配应用于酸驼乳发酵。     

羊肉半干发酵香肠在发酵和成熟过程中游离脂肪酸变化研究

本实验通过以从内蒙古传统肉肠中分离得到的植物乳杆菌(X3-2B)为发酵剂来制作发酵香肠,对羊肉半干发酵香肠在发酵与成熟过程中水分活度,水分含量,p H及游离脂肪酸的组成和含量变化进行研究。结果显示,在发酵过程,植物乳杆菌标准菌组和植物乳杆菌(X3-2B)组的p H下降明显,在干燥、成熟过程中,p H有上升趋势,达到5.2左右。植物乳杆菌(X3-2B)组的Aw值和水分含量都低于植物乳杆菌标准菌。在发酵过程中,植物乳杆菌标准菌组的单不饱和脂肪酸高于其他组;在干燥和成熟过程中,植物乳杆菌标准菌组的单不饱和脂肪酸低于植物乳杆菌(X3-2B)组。多不饱和脂肪酸在发酵和成熟过程中,植物乳杆菌标准菌组高于其他组。研究表明,在羊肉半干发酵香肠发酵和成熟过程中,发酵剂对脂肪酸的成分和含量有一定的影响。     

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。     

直投式发酵辣椒复合菌剂的制备

为开发发酵辣椒复合菌剂,提高发酵辣椒工业生产效率,对从自然发酵辣椒中筛选鉴定出的菌株进行产酸能力、耐酸性、耐盐性和安全性等发酵能力测定,选择出发酵菌剂的备选菌株为植物乳杆菌、乳酸乳球菌和枯草芽孢杆菌。通过接种配比试验和对发酵条件的优化,得出复合菌剂的最佳配方:菌液(枯草芽孢杆菌乳酸乳球菌植物乳杆菌)体积比为141,接种量6%,发酵时间66h,盐浓度4%。该条件下得出的发酵辣椒产酸量为0.77%;感官评定分数17.525。     

5种不同益生菌发酵南瓜浆的发酵性能及抗氧化活性研究

目的 比较分析5种益生菌发酵南瓜浆的品质和抗氧化活性, 为筛选发酵南瓜浆的优良菌株奠定基础。方法 利用植物乳杆菌、嗜酸乳杆菌、戊糖乳杆菌、保加利亚乳杆菌和嗜热链球菌5种不同益生菌发酵南瓜浆, 比较分析发酵过程中活菌数、pH、总酸含量、还原糖含量、总酚含量、1,1-二苯基-2-三硝基苯肼[1,1-diphenyl-2-picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl, DPPH]自由基清除率能力和2,2’-联氮-双-(3-乙基苯并噻唑啉-6-磺酸)[2,2’-azino-bis(3-ethylbenzthiazo-line-6-sulfonic acid), ABTS]自由基清除能力。结果 嗜热链球菌和植物乳杆菌适应南瓜浆发酵体系能力最强, 发酵结束后, 植物乳杆菌发酵南瓜浆活菌数含量最高, 达9.89 lgCFU/mL, 较发酵前提高了100倍; 5种益生菌均能产酸, 其中植物乳杆菌产酸能力最强, 对碳源的代谢能力也最强, 植物乳杆菌、嗜热链球菌发酵后南瓜浆多酚含量增加最显著(P<0.05)。抗氧化实验显示, 植物乳杆菌和嗜热链球菌具有较好的抗氧化能力。结论 植物乳杆菌和嗜热链球菌更适合发酵南瓜浆。     

微生物固态发酵菜籽粕营养特性的研究

以普通菜籽粕为原料,选用枯草芽孢杆菌、地衣芽孢杆菌、植物乳杆菌、啤酒酵母、季也蒙毕赤酵母及黑曲霉等菌种,通过单菌株与混菌株发酵试验,研究发酵对菜籽粕中粗蛋白和抗营养因子含量的影响。结果表明,芽孢杆菌的蛋白酶活性高于其他菌株;混菌株发酵效果明显优于单菌株发酵;混菌株发酵中枯草芽孢杆菌、植物乳杆菌和啤酒酵母三菌种组合发酵能较好地提高菜籽粕作为饲料蛋白的品质,此时其粗蛋白质增加率和硫代葡萄糖苷(硫苷)、唑烷硫酮(OZT)、单宁、植酸降解率分别为5.37、93.44、99.99、34.86、18.15%(干基)。     

成熟时间对羊肉发酵香肠品质及风味的影响

通过添加清酒乳杆菌及木糖葡萄球菌制作发酵羊肉香肠,采用气相色谱-质谱(GC-MS)联用技术测定不同成熟时间(0,3,4,5,6 d)香肠脂肪酸及风味组成,探究不同成熟时间对羊肉发酵香肠食用品质及风味累积的影响,旨在确定香肠成熟最佳时间.结果表明:随着成熟时间的延长,香肠pH值、水分活度(aw)显著(P<0.05)下降,...     

Identification of potential probiotic starter cultures for Scandinavian-type fermented sausages

Potential probiotic cultures suitable as starter cultures for the Scandinavian-type fermented sausages were identified among strains well-adapted to fermented meats as well as strains originating from a culture collection. From 15 different fermented meat products, 22 strains were isolated as dominant non-starter lactic acid bacteria (NSLAB). The isolates were identified by RAPD, API and sequence analysis of 16S rRNA and showed to be five strains of Lactobacillus sakei, five strains of Lactobacillus farciminis, five strains belonging to the group of Lactobacillus plantarum/pentosus, four strains of Lactobacillus alimentarius, two strains of Lactobacillus brevis and one strain of Lactobacillus versmoldensis. Heterofermentative strains as well as strains not growing at 37 degrees C and not lowering pH below 5.1 in a meat model were excluded leaving 9 strains for further studies. These strains together with 19 strains from a culture collection were evaluated by in vitro methods including survival upon exposure to pH 2.5 or 0.3% oxgall and adhesion to the human colon adenocarcinoma cell line Caco-2 as well as antimicrobial activity against potential pathogens. Strains that fulfilled all the probiotic criteria and showed to be fast acid producers in a meat model included three strains belonging to the group of Lb. plantarum/pentosus (MF1291, MF1298, MF1300) which originated from the dominant NSLAB of fermented meat products. MF1291 and MF 1298 were further identified as Lb. plantarum and MF1300 as Lb. pentosus. The three strains were all successfully applied as starter cultures for the production of fermented sausage. The viable count at the end of the processing period reached high cell numbers (4.7x10(7)-2.9x10(8) cfu/g) and pH of the sausages decreased to pH 4.8-4.9 without any flavour deviation compared to sausage fermented by a commercial meat starter culture.     

应用于羊肉脱膻的三种发酵剂筛选及发酵特性研究

为筛选出适合发酵羊肉制品的优质发酵剂,对肉葡萄球菌（Staphylococcus carnosus）、植物乳杆菌（Lactobacillus plantarum）和戊糖片球菌（Pedicoccuspentosaceus）的发酵特性进行研究,通过耐盐、耐亚硝酸盐、产酸能力、蛋白质和脂肪分解能力、膻味脂肪酸降解能力、抑菌能力、菌种间拮抗作用等试验对其筛选。结果表明,三株菌对食盐和亚硝酸盐具有较好的耐受性,能在6%的食盐溶液和150 mg/L亚硝酸盐溶液中存活,具有一定产酸能力,除植物乳杆菌无脂肪酶活性,其他两株菌具有蛋白质和脂肪降解能力,膻味脂肪酸降解率可达60%～80%,能抑制病原微生物的生长,且三株菌间无拮抗作用,对羊肉制品的风味和品质无负面影响。因此肉葡萄球菌、植物乳杆菌和戊糖片球菌可进一步应用于发酵羊肉制品的生产和开发。     

Drying Temperature and Time Affect Quality of Chinese-style Sausage Inoculated with Lactic Acid Bacteria

Lactobacillus plantarum, Streptococcus thermophilus and a commercial culture (DS-66) were used as starter culture for manufacturing Chinese-style sausage. The influence of drying temperature and time on the growth of lactic acid bacteria (LAB) and on changes in quality were determined. After drying the sausage at 370 and 45°C for 12 hr, the population of LAB had increased from an initial 10⁶ CFU/g to 10⁸ and 10⁷ CFU/g, respectively. The pH value was the lowest for the sausage dried at 37°C. Nitrite residuals decreased rapidly with increased drying time. Starter cultures increased the amino nitrogen level and suppressed ammonia nitrogen production.     

羊肉发酵香肠的理化性质初探

采用干酪乳杆菌和玫瑰色微球菌按一定比例混合的组合发酵剂生产羊肉发酵香肠，并对其理化性质进行了研究。结果表明：实验组的脂肪酸总量变化不显著，氨基酸的含量比对照组显著增加，亚硝酸盐的含量明显下降。     

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.     

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.     

Microbial and Physicochemical Characterization of the Horse Meat in Fermented Sausage

In this study, 150 lactic acid bacterial strains, originating from horse meat, were subjected to a step-by-step screening and characterization to search for potential protective cultures to be used in the meat industry. Strains were first tested for their homofermentation and salt tolerance. Second, the antibacterial capacities towards Listeria monocytogenes were determined in an agar spot test. In total, 50% of the tested strains were inhibitory towards Listeria monocytogenes. However, only 12 strains produced a bacteriocin. Finally, three strains with strong bacteriocin activity were competitively evaluated by comparing their growth rate, acidifying character and lactic acid production at 15°C under anaerobic conditions in a liquid broth. All three strains had a fast growth rate with rapid acidification caused by the production of high levels of lactic acid. Based on this Lactobacillus sakei was used as starter culture for producing sausage horse meat. In this study, fermentations were followed analyzing the microbiological and physicochemical aspects of this product. The sausages were characterized based on microbial activity of lactic acid bacteria that resulted in a product with a final pH of about 4.56. No Listeria monocytogenes, Salmonella spp. nor Sulfite reducing clostridia were ever isolated from the raw materials or the fermented sausages during the maturation, reflecting the safety of this product. The final water activity of the product was 0.85. Lactobacillus sakei was efficient in reducing amine production since this strain caused a quick pH drop during sausage fermentation.     

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).