首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 78 毫秒
1.
从泡菜中分离鉴定适合尾菜(废弃白菜叶、青笋叶)青贮的乳酸菌,获得产酸能力强、青贮效果好的2株菌株SD2和SD4,并对其培养条件进行研究。结果表明,菌株SD2、SD4最适培养温度分别为35 ℃、37 ℃;最适培养时间分别为20 h、16 h;最适初始pH值均为6.5;最适接种量均为6%。菌株SD2和SD4分别在30 ℃条件下进行尾菜发酵7 d后,pH值均<4.0,乳酸菌活菌数>1×108 CFU/g。对菌株SD2和SD4进行形态学、生化检测及16S rRNA序列分析,鉴定菌株SD2为植物乳杆菌(Lactobacillus plantarum),菌株SD4为发酵乳杆菌(Lactobacillus fermentum)。  相似文献   

2.
从江西萍乡自然发酵搓菜中筛出7株优势菌种,对其发酵性能及菌种间相互作用进行研究,筛选发酵性能较好且菌种间无拮抗作用的菌种,复配发酵搓菜.通过质构分析、颜色测定、感官评定得出最佳发酵菌种配比,最后比较自然发酵与优选菌剂发酵搓菜挥发性风味物质的差异.结果表明,7株菌都有良好的发酵性能,且以Pichia kudriavzev...  相似文献   

3.
目的 研究尾菜有机肥对土壤肥力及圆白菜和小茴香的产量与品质的影响,筛选出适宜不同蔬菜的尾菜有机肥用量.方法 将不同量尾菜有机肥和商品有机肥通过田间实验应用于圆白菜和小茴香2种蔬菜,研究尾菜有机肥对土壤及蔬菜的影响.结果 尾菜有机肥能提升土壤碱解氮、速效磷和速效钾含量,与CK差异达显著水平;与CK相比,施用尾菜有机肥后,...  相似文献   

4.
为研究微生物菌剂对全株玉米青贮发酵感官品质的影响,对5个玉米品种实施全株青贮,分别设置添加3种不同青贮发酵剂为3个处理组,不添加为对照组,60 d后对全株青贮玉米进行色泽、气味、结构、水分、p H值方面的感官评定.结果表明,3种不同青贮饲料发酵剂对玉米青贮效果的影响有差异,主要表现在对pH值方面的影响,其中正大808青...  相似文献   

5.
莱昂是敌荣在收购、倒运、保管及生产预处理过程中产生的一些甜菜碎块及断掉的尾根的统称,其量一般占l%~2%对甜菜.菜尾含糖一般为10%~13%对菜。目前利用水浮式菜尾分离器可使菜尾回收率达叨%左右.但用此法回收的菜尾较碎,且夹带来物较多,与甜菜一起送到切丝机,严重影响切经质量和渗出器的正常操作,给生产带来很多麻烦,使得一些精厂的菜尾没有得到全部回收,造成很大浪费。鉴于此,我们做了采用压榨法提取荣尾糖分的试验.l试验主要设备与仪器小型破碎机、小到挤压机、折光计、检精计等。2试验步骤与方法①方法一菜尾~破碎~…  相似文献   

6.
《食品与发酵工业》2016,(12):98-104
以实验室保藏的1株乳酸菌与1株酵母菌为研究对象,采用真空冷冻干燥技术制作活菌制剂,并对菌剂发酵性能进行评估。结果表明:经4℃、6 500 r/min,13 min离心收集菌体,再以10%蛋白胨+3%维生素C为保护剂,真空冷冻干燥后,酵母菌与乳酸菌冻干存活率分别达86.3%、87.8%。将自制复合菌剂用于甘蓝发酵,并与市售菌剂、自然发酵比较:添加自制菌剂发酵的甘蓝p H、总酸度提前2 d趋于稳定,分别为5.4、11.05 g/100 g;亚硝酸盐含量更低,最大值仅为7.07 mg/kg;初步认定乙醇(42.46%)、苯乙醇(13.47%)、4-乙基苯酚(6.77%)、顺-3-己烯醇(4.48%)为自制菌剂发酵甘蓝的主要风味物质。此复合菌剂具有较好的产酸产香能力,其在泡菜行业具有良好的应用前景。  相似文献   

7.
0 前言碎甜菜与尾根是甜菜在搬运、装卸、流送、洗涤等过程中甜菜之间或甜菜与外界发生剧烈碰撞而产生 ,一般为甜菜量的 3%~ 5 % ,含糖随甜菜品质的差异而有所不同 ,一般较甜菜含糖低 4个左右 ,具有可观的回收价值。国外甜菜糖厂在此方面已有成功的经验 ,国内也在碎甜菜与尾根的回收方面做了许多有益的尝试 ,但均因除沙、除石难度大 ,以及其它因素造成菜丝质量下降 ,影响渗出效果等原因而未能收到理想效果。为了提高出糖率 ,降低损失 ,提高经济效益 ,针对碎甜菜和尾根的回收 ,我公司在 2 0 0 1年检修期采用了湿法输送的回收方法 ,经 2 0 0…  相似文献   

8.
为了有效解决高原夏菜尾菜加工处理过程中废水色度大、不能达标排放的难题,本文以脱色率为评价指标,在单因素实验的基础上,利用响应面法研究活性炭对高原夏菜尾菜废水的脱色条件。得到最佳脱色条件为:活性炭添加量为1.85%,p H为6.1,脱色时间为66min,高原夏菜尾菜废水的脱色率达到85.04%。   相似文献   

9.
以植物乳杆菌为发酵菌种,以膨化豆粉为原料制作一种价廉物美的发酵菌剂,用该菌剂对普通饲料进行发酵得到发酵饲料,该发酵饲料喂养的肉猪猪肉品质和喂养环境卫生条件均好于普通饲料。  相似文献   

10.
小麦秸秆和白菜尾菜混合发酵试验   总被引:2,自引:0,他引:2  
对尾菜与小麦秸秆进行了混合发酵试验,并比较分析发酵前后的营养物质含量变化。结果表明,在常温下,对添加不同量原料及酵母后的发酵效果进行比较发现,以小麦秸秆∶白菜尾菜7∶3、玉米粉添加量5%、酵母粉添加量2%的混合比例,在室温、pH值6.6条件下发酵2 d,可提高白菜混合物中的粗蛋白和脂肪含量。  相似文献   

11.
This study examined the effect of applying different bacterial inoculants to corn silage at the time of ensiling on the performance of lactating dairy cows. Corn plants were harvested at 35% dry matter (DM), chopped, and ensiled in 2.4-m-wide bags after application of (1) no inoculant (CON); (2) Biotal Plus II (B2) containing Pediococcus pentosaceus and Propionibacteria freudenreichii; (3) Buchneri 40788 (BUC) containing Lactobacillus buchneri; or (4) Buchneri 500 (B500) containing Pediococcus pentosaceus and L. buchneri. All inoculants were supplied by Lallemand Animal Nutrition (Milwaukee, WI). Each of the 4 silages was included in separate total mixed rations consisting of 44% corn silage, 50% concentrate, and 6% alfalfa hay (DM basis). Fifty-two lactating Holstein cows were stratified according to milk production and parity and randomly assigned at 22 d in milk to the 4 dietary treatments. Cows were fed for ad libitum consumption and milked twice daily for 49 d. Dietary treatment did not affect intakes (kg/d) of DM (20.0), crude protein (CP; 3.7), neutral detergent fiber (NDF; 5.7), or acid detergent fiber (ADF; 3.6), or digestibility (%) of DM (73.9) or CP (72.4). However, NDF digestibility was lower in cows fed B2 compared with those fed other diets (45.3 vs. 53.0%). Consequently, cows fed B2 had lower digestible NDF intake (kg/d) than those fed other diets (2.5 vs. 3.0 kg/d). Dietary treatment did not affect milk yield (32.3 kg/d), efficiency of milk production (1.61), concentrations of milk fat (3.18%) and protein (2.79%), or yields of milk fat (1.03 kg/d) and protein (1.26 kg/d). Inoculant application to corn silage did not affect milk yield or feed intake of cows.  相似文献   

12.
Natural populations of lactic acid bacteria (LAB) and silage fermentation of vegetable residues were studied. Fifty-two strains of LAB isolated from cabbage, Chinese cabbage, and lettuce residues were identified and characterized. The LAB strains were gram-positive and catalase-negative bacteria, which were divided into 6 groups (A to F) according to morphological and biochemical characteristics. The strains in group A were rods that did not produce gas from glucose and formed the d and l isomers of lactate. Groups B and C were homofermentative cocci that formed l-lactic acid. Groups D, E, and F were heterofermentative cocci that formed d-lactic acid. Based on 16S rDNA gene sequence analysis, group A to F strains were identified as Lactobacillus plantarum, Lactococcus piscium, Lactococcus lactis, Leuconostoc citreum, Weissella soli and Leuconostoc gelidum, respectively. The prevalent LAB, predominantly homofermentative lactobacilli, consisted of Lactobacillus plantarum (34.6%), Weissella soli (19.2%), Leuconostoc gelidum (15.4%), Leuconostoc citreum (13.5%), Lactococcus lactis (9.6%), and Lactococcus piscium (7.7%). Lactobacillus plantarum was the dominant member of the LAB population in 3 types of vegetable residues. These vegetable residues contained a high level of crude protein (20.2 to 28.4% of dry matter). These silages prepared by using a small-scale fermentation system were well preserved, with low pH and a relatively high content of lactate. This study suggests that the vegetable residues contain abundant LAB species and nutrients, and that they could be well preserved by making silage, which is a potentially good vegetable protein source for livestock diets.  相似文献   

13.
The present study aimed to investigate the effects of 2 corn silage inoculation strategies (homofermentative vs. heterofermentative inoculation) under field conditions and to monitor responses in silage variables over the feeding season from January to August. Thirty-nine commercial dairy farms participated in the study. Farms were randomly assigned to 1 of 3 treatments: control (nonactive carrier; Chr. Hansen A/S, Hørsholm, Denmark), Lactisil (inoculation with 1 × 105Lactobacillus pentosus and 2.5 × 104Pediococcus pentosaceus per gram of fresh matter; Chr. Hansen A/S), and Lalsil Fresh (inoculation with 3 × 105Lactobacillus buchneri NCIMB 40788 per gram of fresh matter; Lallemand Animal Nutrition, Blagnac, France). Inoculation with Lactisil had no effects on fermentation variables and aerobic stability. On the contrary, inoculation with Lalsil Fresh doubled the aerobic stability: 37, 38, and 80 ± 8 h for control, Lactisil, and Lalsil Fresh, respectively. The effect of Lalsil Fresh on aerobic stability tended to differ between sampling times, indicating a reduced difference between treatments in samples collected in April. Lalsil Fresh inoculation increased silage pH and contents of acetic acid, propionic acid, propanol, propyl acetate, 2-butanol, propylene glycol, ammonia, and free AA. The contents and ratios of dl-lactic acid, l-lactic acid relative to dl-lactic acid, free glucose, and dl-lactic acid relative to acetic acid decreased with Lalsil Fresh inoculation. Lalsil Fresh inoculation increased the silage counts of total lactic acid bacteria and reduced yeast counts. The Fusarium toxins deoxynivalenol, nivalenol, and zearalenone were detected in all silages at all collections, but the contents were not affected by ensiling time or by inoculation treatment. The effect of inoculation treatments on milk production was assessed by collecting test-day results from the involved farms and comparing the actual milk production with predicted milk production within farm based on test-day results from 2007 and 2008. The average milk production of lactating cows at test days during the study (January to September 2009) was 30.7 ± 0.5 kg of energy-corrected milk/d. Milk production was 104.6 ± 0.7% of the predicted yield and did not differ among treatments. In conclusion, the present study showed that homofermentative inoculants might not compete efficiently or might not deviate sufficiently from the epiphytic flora on whole-crop corn to affect fermentation in standard qualities of corn silage. Heterofermentative inoculation increased aerobic stability and numerous fermentation variables. None of the treatments affected milk production, and more-stable corn silage seemed to have a similar production value as compared with less-stable homofermented silage. Heterofermented silage can be evaluated for its properties to limit aerobic silage deterioration in the feed chain.  相似文献   

14.
《Journal of dairy science》2022,105(6):5024-5043
Silage inoculants are commonly used as a tool to improve the fermentation and aerobic stability of corn silage fed to dairy cows. However, their effectiveness can be inconsistent. Our objective was to determine the effect of the dry matter (DM) content of freshly chopped whole-plant corn on its microbial community as affected by an inoculant containing Lentilactobacillus hilgardii, Lentilactobacillus buchneri, and Pediococcus pentosaceus on improving the aerobic stability of silage. Whole-plant corn was harvested at low (31.80%, LDM), medium (33.32%, MDM), or high (39.44%, HDM) DM content and treated with nothing (CTR) or an inoculant (INO) containing L. hilgardii CNCM I-4785 at 150,000 cfu/g fresh forage, L. buchneri NCIMB 40788 at 150,000 cfu/g fresh forage, P. pentosaceus NCIMB12455 at 100,000 cfu/g of fresh forage, β-glucanase (5,750 IU/g), and xylanase (30,000 IU/g) and ensiled for 20 and 60 d. Data were analyzed as a completely randomized design in a 3-by-2 factorial arrangement of treatments. Fresh LDM forage had a higher concentration of reducing sugars, a less rich, diverse, and even bacterial community, and greater relative abundance of Saccharomycetales than MDM and HDM forages. Silages at 20 and 60 d, inoculated LDM had a more modest proliferation of culturable lactic acid bacteria than inoculated MDM. At 20 d, regardless of treatment, LDM had greater concentrations of lactic and acetic acids. Also at 20 d, LDM had lower numbers of culturable yeasts but greater relative abundance of Enterobacteriaceae than MDM and HDM. For silage at 20 d, HDM silage was more aerobically stable than LDM and MDM and inoculation improved aerobic stability 1.8-fold compared with CTR. For silage at 60 d, there was an interaction between DM content and inoculation. The improvements in stability by inoculation, compared with CTR, were greater in MDM (261 vs. 41 h) and HDM (320 vs. 66 h) silages than in LDM (85 vs. 46 h). The lower DM content and possible slower pH decline in LDM might have facilitated the development of undesirable bacteria and coupled with its greater concentration of reducing sugars and lactic and acetic acids, which are substrates for aerobic microorganisms, might explain the more modest improvements in aerobic stability from inoculation in LDM compared with MDM and HDM. Our findings suggest that the DM content of whole-plant corn affected its epiphytic microbial community and the effectiveness of the inoculant, which improved aerobic stability at all DM but to a greater extent in HDM and MDM than in LDM, especially after 60 d of ensiling.  相似文献   

15.
The first objective of this study was to examine effects of adding Escherichia coli O157:H7 with or without chemical or microbial additives on the bacterial diversity and composition of alfalfa silage. The second objective was to examine associations between the relative abundance of known and unknown bacterial species and indices of silage fermentation quality. Alfalfa forage was harvested at 54% dry matter, chopped to a theoretical length of cut of 19 mm, and ensiled in quadruplicate in laboratory silos for 100 d after the following treatments were applied: (1) distilled water (control); (2) 1 × 105 cfu/g of E. coli O157:H7 (EC); (3) EC and 1 × 106 cfu/g of Lactobacillus plantarum (EC+LP); (4) EC and 1 × 106 cfu/g of Lactobacillus buchneri (EC+LB); and (5) EC and 0.22% propionic acid (EC+PA). After 100 d of ensiling, the silage samples were analyzed for bacterial diversity and composition via the Illumina MiSeq platform (Illumina Inc., San Diego, CA) and chemically characterized. Overall, Firmicutes (74.1 ± 4.86%) was the most predominant phylum followed by Proteobacteria (20.4 ± 3.80%). Relative to the control, adding E. coli O157:H7 alone at ensiling did not affect bacterial diversity or composition but adding EC+LP or EC+LB reduced the Shannon index, a measure of diversity (3.21 vs. 2.63 or 2.80, respectively). The relative abundance of Firmicutes (69.2 and 68.8%) was reduced, whereas that of Proteobacteria (24.0 and 24.9%) was increased by EC+LP and EC+PA treatments, relative to those of the control (79.5 and 16.5%) and EC+LB (77.4 and 18.5%) silages, respectively. Compared with the control, treatment with EC+LP increased the relative abundance of Lactobacillus, Sphingomonas, Pantoea, Pseudomonas, and Erwinia by 426, 157, 200, 194, and 163%, respectively, but reduced those of Pediococcus, Weissella, and Methylobacterium by 5,436, 763, and 250%, respectively. Relative abundance of Weissella (9.19%) and Methylobacterium (0.94%) were also reduced in the EC+LB silage compared with the control (29.7 and 1.50%, respectively). Application of propionic acid did not affect the relative abundance of Lactobacillus, Weissella, or Pediococcus. Lactate concentration correlated positively (r = 0.56) with relative abundance of Lactobacillus and negatively (r = ?0.41) with relative abundance of Pediococcus. Negative correlations were detected between ammonia-N concentration and relative abundance of Sphingomonas (r = ?0.51), Pantoea (r = ?0.46), Pseudomonas (r = ?0.45), and Stenotrophomonas (r = ?0.38). Silage pH was negatively correlated with relative abundance of Lactobacillus (r = ?0.59), Sphingomonas (r = ?0.66), Pantoea (r = ?0.69), Pseudomonas (r = ?0.69), and Stenotrophomonas (r = ?0.50). Future studies should aim to speciate, culture, and determine the functions of the unknown bacteria detected in this study to elucidate their roles in silage fermentation.  相似文献   

16.
This study determined how the fermentation and aerobic stability of corn silage are affected by treatment with molasses or 2 dual-purpose inoculants applied at or above the recommended rate. Corn forage (DeKalb 69-70) was harvested at 39% dry matter (DM) and ensiled after treatment with no additives (control, CON), molasses (MOL), Buchneri 500 inoculant, or Pioneer 11C33 inoculant. Molasses was applied at 3% of forage DM. Buchneri 500 was applied at the recommended rate of 8 mg/kg fresh forage to supply 1 × 105 cfu/g of Pediococcus pentosaceus 12455 and 4 × 105 cfu/g of Lactobacillus buchneri 40788 (BB) or at twice the recommended rate (DBB). Pioneer 11C33 inoculant was applied at the recommended rate of 1.1 mg/kg fresh forage to supply 1 × 105 cfu/g of a mixture of Lactobacillus plantarum, L. buchneri, and Enteroccocus faecium (PN) or at twice the recommended rate (DPN). Each treatment was applied in quadruplicate and the treated forages were ensiled within 20-L mini silos for 135 d at 18 to 35°C. Molasses-treated silages had greater ash and starch concentrations than CON silages and greater lactate and ethanol concentrations than other silages. Like CON silages, MOL silages had high yeast counts (>105 cfu/g); consequently, they deteriorated within 30 h as shown by temperature increase. Inoculant-treated silages had lower lactate to acetate ratios than CON or MOL silages largely because they had greater acetate concentrations. Consequently, all inoculant-treated silages had fewer yeasts (<105 cfu/g) and were more stable (>30 h) than CON and MOL silages. When applied at recommended rates, PN and BB had similar effects on silage chemical composition, fermentation, fungal counts, and aerobic stability, except for a lower lactate concentration in PN silages. Concentrations of VFA, and NH3-N, pH, and extent of aerobic stability were similar for PN, DPN, BB, and DBB silages. However, lactate concentration was greater in DPN than in PN. In conclusion, MOL application increased ethanol and lactate concentration and did not improve aerobic stability. Both dual-purpose inoculants made the fermentation more heterolactic and thereby improved the aerobic stability of corn silage. Doubling the rate of application of either inoculant did not further improve fermentation or aerobic stability.  相似文献   

17.
一株细菌型腐乳生产菌株的分离   总被引:1,自引:1,他引:1  
对细菌型腐乳进行腐乳菌株的分离纯化及扩大培养,经多次试验分离出一株蛋白酶活力较高,易培养,不易退化的优良QU1.602藤黄微球菌。原菌在豆粉营养盐培养基上长势最好,生长最适温度为35℃,自然pH。  相似文献   

18.
The objective of this study was to determine if exposure to high temperatures in water affects the viability of various silage inoculants. Inoculants were enumerated on De Man, Rogosa, Sharpe agar to standardize a final count (colony-forming units) in water such that about 500 mL added to 1 tonne of wet forage would achieve a recommended application rate of about 100,000 cfu of lactic acid bacteria (LAB) per gram of wet forage. Testing was done in 4 sequences (SEQ). For each SEQ, inoculants were mixed in deionized water for 45 min at 30°C followed by incubation for 6 h at 30°C (SEQ 1), 35°C (SEQ 2), 40°C (SEQ 3), or 45°C (SEQ 4) in duplicate 125-mL flasks rotating at 125 rpm. After 6 h, rotation was stopped and the temperature was lowered to 30°C for the next 18 h for all SEQ. Numbers of LAB were enumerated at 0, 3, 6, and 24 h. Each sequence was repeated twice. Incubation at a moderate temperature (SEQ 1) did not affect the viability of the microbial inoculants. The viability of the inoculants declined with increasing temperature (SEQ 2 to 4) but the effect varied by inoculant. For some inoculants exposure to 35°C resulted in substantial decreases in viable cells (loss of 0.5 to 1 log cfu/mL). Incubation at higher temperatures resulted in even greater losses in viability for some inoculants. Losses of more than 0.5 log cfu/mL would most likely make the application of these inoculants ineffective in the field. Lactobacillus plantarum MTD/1 was the most thermotolerant organism tested, because it was unaffected by all temperatures (30 to 45°C) after 3 h of incubation. Lactobacillus plantarum MTD/1 and Lactobacillus buchneri 40788 also appeared to have better thermotolerance as their numbers substantially increased between 6 and 24 h in SEQ 4. These data show that some silage inoculants are more thermotolerant than others and that precautions should be taken to ensure that microbial inoculants that are applied to forage do not reach elevated temperatures during use.  相似文献   

19.
This study examined the effect of applying different bacterial inoculants on the fermentation and quality of corn silage. Corn plants were harvested at 35% DM, chopped, and ensiled in 20-L mini silos after application of (1) deionized water (CON) or inoculants containing (2) 1 × 105 cfu/g of Pediococcus pentosaceus 12455 and Propionibacteria freudenreichii (B2); (3) 4 × 105 cfu/g of Lactobacillus buchneri 40788 (BUC); or (4) 1 × 105 cfu/g of Pediococcus pentosaceus 12455 and 4 × 105 cfu/g of L. buchneri 40788 (B500). Four replicates of each treatment were weighed into polyethylene bags within 20-L mini silos. Silos were stored for 575 d at ambient temperature (25°C) in a covered barn. After silos were opened, aerobic stability, chemical composition, and yeast and mold counts were determined. The DNA in treated and untreated silages was extracted using lysozyme/sodium dodecyl sulfate lysis and phenol/chloroform and used as a template for a conventional PCR with primers designed on the 16S rRNA gene to detect the presence of L. buchneri in all silage samples. Acetic acid concentration was greater in B2 silages versus others (6.46 vs. 4.23% DM). Silages treated with BUC and B500 had lower pH and propionic acid concentration and greater lactic acid concentration than others. The B500 silage had the greatest lactic:acetic acid ratio (1.54 vs. 0.41), and only treatment with BUC reduced DM losses (5.0 vs. 14.3%). Yeast and mold counts were less than the threshold (105) typically associated with silage spoilage and did not differ among treatments. Consequently, all silages were very stable (>250 h). Aerobic stability was not improved by any inoculant but was lower in B500 silages versus others (276 vs. 386 h). The conventional PCR confirmed the presence of similar populations of L. buchneri in all silages. This may have contributed to the prolonged aerobic stability of all silages.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号