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1.
S. P. Antai 《Plant foods for human nutrition (Dordrecht, Netherlands)》1990,40(4):289-296
The effect of fermentation on the nutrient quality of cassava was investigated. Chemical analysis revealed a general increase in ash, fibre and crude protein content of the fermented cassava mash, while the carbohydrate content showed a substantial decrease. The results of the chemical analysis indicated that fermentation resulted in a slight protein enrichment of the fermentated cassava mash. When active yeast cells were inoculated into the cassava mash before fermentation, The yeast cells grew and generated additional cell mass which was reflected in a higher content of crude protein in the fermented cassava mash. Results obtained also revealed that 3.3% concentration of yeast cell inoculum added to cassava mash before commencement of fermentation was optimum for maximal crude protein formation. 相似文献
2.
S. P. Antai P. M. Mbongo 《Plant foods for human nutrition (Dordrecht, Netherlands)》1994,46(4):345-351
Mash prepared from cassava peels was inoculated with eitherSacchromyces cerevisiae orCandida tropicalis and then left to ferment for 7 days. Chemical analysis of the fermented mash showed substantial increase in crude protein content and decrease in carbohydrate content of the mash. The results also revealed slight increases in the ash, fibre and lipid content of the fermented mash. It was further observed that, when the mash was supplemented with inorganic nitrogen sources (urea, ammonium sulfate or sodium nitrate) before commencement of fermentation, the amount of crude protein formed was almost doubled. This enhanced crude protein production was highest in the mash supplemented with urea. Temperature of 30 °C, pH of 5.5 and moisture concentration of 130% were found to be optimum for crude protein formation by the organisms growing on the mash. 相似文献
3.
从腐烂的木薯中分离得到1株降解生淀粉能力较强的菌株ITBB FC2,经形态学鉴定和18S rDNA序列分析,初步鉴定属于黑曲霉（Aspergillus niger）。该菌株用2％生木薯粉培养基摇瓶,37 ℃,200 r/min培养3 d后,发酵液葡萄糖含量为970 mg/L,生淀粉酶活力为495.04 U/mL。采用固体产酶培养基（麸皮 ∶ 水=1 ∶ 1）培养,所得酶活力为6 330 U/g。酶反应最适pH为4.0~5.0。Ca2+对酶活力有一定的促进作用。 相似文献
4.
木薯渣固态发酵植酸酶的条件研究 总被引：5，自引：0，他引：5
木薯渣粗蛋白及无机盐含量较低,与麸皮、米糠混合或同时添加无机氮源及无机盐,可作为发酵培养基合成植酸酶。高浓度的磷抑制植酸酶的合成。最佳发酵条件为：木薯渣为唯一碳原,添加 ２％ ＮＨ４ＮＯ３, ０．０１％ Ｋ２ＨＰＯ４, ０．０５％ ＭｇＳＯ４·７Ｈ２Ｏ, ０．０５％ ＫＣＩ, ０．０１％ ＦｅＳ－Ｏ４· ７Ｈ２Ｏ, ０．９％ ＳＤＳ,培养基水分含量 ６０％～６５％, １０ｇ木薯渣／２５０ ｍＬ三角瓶,接种量为２ｍＬ菌悬液（２．８×１０个孢子／ｍＬ）,自然 ｐＨ值,培养温度 ２８～３１℃,第８ｄ达产酶高峰,高峰期产酶量为 ６７３０ Ｕ／ｇ干曲。 相似文献
5.
为阐明茶叶籽水浆发酵微生物种类及其在发酵过程中的作用特性,对发酵5βh的茶叶籽水浆发酵液进行微生物分离与提纯,从中分离纯化出1株菌株。经形态观察、16βS rDNA及pheS基因测序与比对、系统发育树的构建与分析,确定该菌株为植物乳杆菌（Lactobacillus plantarum ssp. Plantarum）;命名该菌株为茶叶籽乳杆菌（Lactobacillus plantarum ssp. plantarum JJZ21）,菌种保藏号为CCTCC M 2016471。在茶叶籽水浆发酵过程中,发酵液中茶叶籽乳杆菌的数量在5βh之后逐渐快速增加,至12~15βh之间达到最大值,之后又逐渐降低,至22βh后,逐渐趋于稳定。伴随茶叶籽乳杆菌数量的增加,发酵液中的干物质含量、可溶性糖含量、可溶性蛋白含量及其pH均明显下降,呈极显著（P<0.01）负相关性。茶叶籽乳杆菌通过消耗发酵液中的可溶性糖及可溶性蛋白等物质,向发酵液中分泌乳酸等酸性有机物,导致发酵液pH逐渐降低,为发酵液中的油脂体上浮以及茶叶籽水浆发酵分层现象发生奠定了基础。 相似文献
6.
O. K. Achi 《Plant foods for human nutrition (Dordrecht, Netherlands)》1992,42(4):297-304
Okpiye is a food condiment prepared by the fermentation ofProsopis africana seeds. The traditional process for the production and microbiological characteristics of the condiment were investigated. During laboratory fermentation that lasted 96h, the mesquite seeds underwent a natural fermentation that was characterised by the growth of microorganisms to 106–108 cfu/g. Several species of bacteria especiallyB. subtilis, B. licheniformis, B. megaterium, Staphylococcus epidermidis andMicrococcus spp were found to be the most actively involved organisms. However, significant contributions to the microbial ecology were made byEnterobacter cloacae andKlebsiella pneumoniae. Lactobacillus spp were present in low numbers towards the end of the fermentation. The presence ofProteus andPseudomonas spp in traditional fermented samples demonstrate the variability which may exist in the microflora of individual fermented samples. Variations in the important microbial groups show thatBacillus spp were the most prevalent species and occurred until the end of fermentation. Temperature, pH and titratable acidity varied with time and were influenced by the metabolic activities of the microorganisms. 相似文献
7.
Studies on the enhancement of the traditional production of Ugba (a protein-rich fermented food) from African oil bean seeds were undertaken by fermenting the bean seeds at different temperatures, relative humidities (RH) and microenvironments. Fermentation was monitored by pH, texture, amino-nitrogen content and the viable cell count of the substrate. The 40 °C, 98% RH or the 130 m high density polyethylene (HDPE) treatment increased the fermentation microflora from ca. 106 CFU/g to ca. 108 CFU/g with high initial changes in pH (5.8–ca. 7.9) and texture (2.0 kg/cm2 to between 1.4 kg/cm2 and 0.9 kg/cm2) in 24 hours. Products with amino-nitrogen contents of between 12.00 mg N/100 g dry matter and 14.00 mg N/100 g dry matter were obtained in 3 days. The cell count of the 30 °C, 80% RH or 70 m treatment increased from 106 CFU/g to ca. 107 CFU/g and the pH increased from 5.8 to about 6.7 with a coincident decrease in the texture value from 2.0 kg/cm2 to about 1.7 kg/cm2 in 24 hours. Products with amino-nitrogen contents between 15.00 mg N/100 g dry matter and 19.2 mg N/100 g dry matter were obtained after 3 days. Changes in the fermentation indicators were not significant at p0.05 (pH and texture) and at p0.01 (amino-nitrogen) after 3 days for the 25 °C, 59.9% RH or 50 m low density polyethylene (LDPE) treatment. Products of fermentation at the combined optimal conditions (80% RH, 35 °C and 70 m HDPE) compared very well with the traditionally fermented products in terms of pH, texture and amino-nitrogen content. 相似文献
8.
Adewusi S.R.A. Ojumu T.V. Falade O.S. 《Plant foods for human nutrition (Dordrecht, Netherlands)》1999,53(4):367-380
Changes in pH, titratable acidity and mineral content (Ca, Fe, Mg, Zn) were estimated in processed cassava products while the mineral content of raw and blanched amaranthus vegetable was determined. pH of fresh cassava (6.5) decreased as total organic acid (0.07%) increased with fermentation period. Fufu and lafun had the lowest pH and the highest total organic acids contents. Fermentation of cassava increased the total calcium and iron contents, reduced magnesium level while zinc remained fairly constant in grated cassava but was reduced when soaked in water (for the preparation of fufu and lafun). Fermentation also increased the availability of these selected minerals in both cassva products and simulated cassava-vegetable diets. Blanching reduced the mineral content of amaranthus vegetable but increased mineral availability. Fermentation of cassava and blanching of vegetables play an important role in making minerals more available and these processing methods should be encouraged to potentially ameliorate the disease states associated with mineral deficiency. 相似文献
9.
Suitability of using sieved or unsieved maize mash for production of “OGI” — A fermented cereal food
Proximate analysis of sieved and unsieved maize mash revealed that there was a decrease in the protein and lipid content of the sieved maize mash as compared to that of the unsieved maize mash. Crude fibre and ash was completely absent in the sieved maize mash, while they were present in the unsieved mash.Chemical analysis of the fermented unsieved maize mash revealed an increase in the protein content from 9.9% (unfermented) to 13.4% after 3 days of fermentation, whereas the protein content of the sieved maize mash increased from 7.1% (unfermented) to 8.4% after the same period of fermentation. Furthermore, the results revealed that the protein content of the fermented unsieved maize mash was 32.1% higher than that of the fermented sieved maize mash indicating that the unsieved maize mash was of a better nutrient quality and should be preferred to sieved maize mash for use in Ogi production. 相似文献
10.
为探讨淡紫拟青霉E7菌株固体放大发酵因子间的关系以获得大量孢子用于田间试验,通过正交试验设计优化固体发酵培养基成分和培养条件组合,并测定外加碳源、氮源、无机盐和装料方式对产孢量的影响。结果表明：以玉米粉+甘蔗渣+麸皮+壳聚糖组成的正交2号配方为最佳复合培养基质,分生孢子产量达7.13×109个/g,以发酵液pH+液相发酵终点+温度+初始含水量组成的正交4号配方为优适培养条件,分生孢子产量达8.97×109个/g;该菌株在优化后的培养基配方中添加0.4％蔗糖、0.2％蛋白胨、0.002％硫酸锰,以双层纱布袋装料按优化后的培养条件放大培养,产孢量最高可达到8.22×1010个/g。优化后的E7菌株发酵产孢培养基基质用量少,发酵成本低,适合于固体放大发酵生产淡紫拟青霉孢子。 相似文献
11.
P. M. HAIGH † 《Grass and Forage Science》1987,42(1):1-8
A total of 1713 samples of silage from commercial farm silos were analysed to investigate the effect of dry matter (DM) content and chemical additives on fermentation as measured by ammonia-N concentration and pH, Increasing DM content without additive use had a major beneficial influence upon fermentation. When silage DM contents were greater than 260 g kg-1 83% of silages were well fermented, with average ammonia-N concentrations of 94 g (kg total N)-1 and pH 4.36. With diminishing DM concentration the proportion of well fermented silages declined. In the DM range 220-260 g kg-1 67% of silages were well fermented with ammonia-N concentrations of 125 g (kg total N)-1 and pH 4.30, in the DM range 180-220 g kg-1 48% were well fermented with ammonia-N at 151 g (kg total N)-1 and pH 4.38 and with DM below 180 g kg-1 no silages were well fermented with ammonia-N concentration of 252 g (kg total N)-1 and pH 4.84. The benefit of chemical additives, albeit at poorly defined and often inadequate rates, was small in comparison to that of increased DM concentration. Below DM concentrations of 180 and 220 g kg-1, the only benefit was that formic acid decreased ammonia-N to 151 g (kg total N)-1 and pH to 4.32 compared with 163 g (kg total N)-1 and pH 4.43 for untreated silages. Within the DM range 220-260 g kg-1 formic acid decreased ammonia-N level to 104 g (kg total N)-1 and pH to 4.07, and there was a slight benefit from using sulphuric acid/formalin which decreased ammonia-N to 117 g (kg total N)-1 and pH to 4.23 compared with 125 g (kg total N)-1 and pH 4.27 for untreated silages. Above 260 g DM kg-1 both formic acid and sulphuric acid/formalin provided a small but consistent decrease in ammonia-N and pH compared with untreated silages. Chemical additive use conferred no other benefit when compared with untreated silage. Calcium formate/sodium nitrite mixtures and acid mixture use provided no benefit in fermentation compared with untreated herbage. 相似文献
12.
13.
Aflata is a gelatinised maize paste, serving as intermediate in the manufacture of kenkey, a traditional cooked fermented maize product of Ghana. The effect of water uptake during soaking of whole or dry-milled maize, the extent of starch damage, dough pH, fermentation time, and of endogenous and added enzymes on pasting and set-back viscosities of aflata dough were studied. Water uptake by coarsely dry-milled maize (grits) reached 0·63 mL/g dry matter in just 1 h, compared with 0·50 mL/gin 3 days for whole grain. High endogenous activity of proteases and carbohydrases were recorded in both grits and whole maize when soaked at 4 °C or 25 °C. These were significantly reduced after soaking at 60 °C. Soaking of grits at 60 °C with a heat-stable protease, or wet fine-milling of fermented grits resulted in significant (P<0·05) increases in pasting viscosities. Peak viscosities increased with fermentation time up to 24 h. Pasting viscosities decreased with repeated wet milling of fermented dough. 相似文献
14.
橘林油脂酵母发酵条件的初步研究 总被引：1，自引：0，他引：1
以橘林油脂酵母（Lipomyces kononenkoae CICC1714）为实验材料,通过设计单因素实验,确定了摇瓶发酵培养的最佳产油条件为：氮源为硫酸铵,碳源为葡萄糖,培养温度28℃,接种量10%,初始pH值为7.0,最适碳氮比为99。优化后批次发酵的生物量为7.01g/L,油脂含量15.91%,油脂产量1.12g/L。经半连续发酵后最终的生物量为24.13g/L,油脂产量为3.06g/L。 相似文献
15.
Aderiye B. I. Ogunjobi A. A. 《Plant foods for human nutrition (Dordrecht, Netherlands)》1998,52(1):49-54
The microflora of white yam ( Dioscorea rotundata L.) slices fermented anaerobically in 1.5 percent brine for five days at room temperature were studied. The hydrolysis of the carbohydrate and the subsequent conversion of sugars and minerals by the fermenting microbes contributed much to the increased microbial load especially within the first 72 hours of fermentation. The organisms implicated in the fermentation include the species of Pediococcus, Lactobacillus and Pseudomonas, Bacillus subtilis and two other Gram negative coccal cells, yet to be identified. The decrease in microbial counts at the latter stage of fermentation was attributed to the high total acidity of the medium, which was about 2.67 times the initial value of 0.027% lactic acid. Meanwhile, the lactic acid bacteria increased continuously throughout the period of fermentation. 相似文献
16.
微生物的发酵作用导致黑茶加工过程中儿茶素的生物转化和总茶多酚含量的下降,这一转化过程的代谢途径和调控机制尚不清楚。通过添加冠突曲霉(Aspergillus cristatum)菌株PE-1和黑曲霉(A. niger)菌株PE-4混合发酵绿茶,采用鉴别培养基平板检测、酶活性测定和酶蛋白分离纯化,研究脂肪酶活性及其对酯型儿茶素的水解作用。两个菌株单菌发酵和混合菌种发酵绿茶条件下均可以检测到脂肪酶活性,混菌发酵酶活力高于两个菌株单菌发酵的酶活力。混菌发酵条件下获得一个分子量约为37 kDa的脂肪酶,对EGCG和ECG有不同的生物转化作用。UPLC检测结果表明,该脂肪酶对EGCG有较好的底物选择性,EGCG的水解率为94.46%,EGC的产率为63.33%;ECG的水解率为15.45%,EC的产率为4.15%。脂肪酶对EGCG和ECG的生物转化将为儿茶素代谢途径的研究和单体儿茶素的生产起到促进作用。 相似文献
17.
Lacto-juices processed by lactic acid fermentation bring about a change in the beverage assortment for their high nutritive
value, vitamins and minerals which are beneficial to human health when consumed. Sweet potato roots (non-boiled/ fully-boiled)
were fermented with Lactobacillus plantarum MTCC 1407 at 28 ± 2°C for 48 h to make lacto- juice. During fermentation both analytical [pH, titratable acidity, lactic
acid, starch, total sugar, reducing sugar (g/kg roots), total phenol and β-carotene (mg/kg roots)] and sensory (texture, taste,
aroma, flavour and after taste) analyses of sweet potato lacto-juice were evaluated. The fermented juice was subjected to
panelist evaluation for acceptability. There were no significant variations in biochemical constituents (pH, 2.2–3.3; lactic
acid, 1.19–1.27 g/kg root; titratable acidity, 1.23–1.46 g/kg root, etc.) of lacto-juices prepared from non-boiled and fully-boiled
sweet potato roots except β-carotene concentration [130 ± 7.5 mg/kg (fully-boiled roots) and 165 ± 8.1 mg/kg (non-boiled roots)].
The panelist evaluation scores ranged from 3–4.8 (in a hedonic scale of 1–5) from moderate liking to very much liking of sweet
potato lacto-juice. Principal component analyses reduced the eight original analytical variables to three independent components
(factors), which accounted for 99.9% of the total variations. Similarly, five original sensory variables were reduced to two
independent components, which accounted for 83.1% of the total variations. 相似文献
18.
Amadi EN Barimalaa IS Omosigho J 《Plant foods for human nutrition (Dordrecht, Netherlands)》1999,54(1):13-20
Bambara groundnut (Vigna subterranea) was fermented to produce a dawadawa-type product using a starter culture of Bacillus licheniformis isolated from naturally fermenting bambara groundnut beans. Fermentation was carried out at 30 and 37 °C for four days and at 45 °C for two days. The pH of the substrate decreased after 24 hours and then rose at 30 and 37 °C but remained constant at 45 °C after the initial drop. Total titratable acidity of the fermenting beans mimicked the pH values. Proximate analyses for moisture, protein and fat of the cotyledons showed an increase in all three constituent at each of the three fermentation temperatures. At the end of fermentation, total available carbohydrate was 55%, 59% and 62% of the original value at 30, 37 and 45 °C, respectively. Fermentation of bambara groundnut at 45 °C for two days is recommended as the ideal fermentation temperature and time. 相似文献
19.
Respiration losses, effect of sugar content, formic acid addition and inoculation were evaluated in relation to initial fermentation and silage quality in three experiments. Changes in the content of fermentable substrate during post–harvest respiration and initial fermentation were studied in the laboratory. Soluble carbohydrates were estimated as glucose, fructose, sucrose, fructans and starch by an enzymatic method.
About 70% of the sugars remained after 30 h of conventional wilting, as opposed to less than 50% in a chopped sample kept in the dark. During the first days of fermentation the metabolic activity was very intensive. Sugars, which accounted for 10% of the dry matter, were fermented within 4 d. There were indications, mainly in clover silages, that substances other than water-soluble carbohydrates were used as energy sources.
Low-sugar crops were obtained by shading the fields. After 3 d the sugar in the grass had decreased to half of the original content. This effect was less pronounced in clover. The amount of available substrate and dry matter (DM) content had a major influence on silage quality. In an unwilted crop at least 25 g of water-soluble carbohydrate was needed per kg of fresh material to obtain an acceptable silage quality in the controls, while 20 g was sufficient in inoculated silage. Formic acid addition makes the fermentation less sensitive to water–soluble carbohydrate content. Inoculation of willed silage increased lactic acid production and decreased the pH. There was also less variation in silage quality. 相似文献
About 70% of the sugars remained after 30 h of conventional wilting, as opposed to less than 50% in a chopped sample kept in the dark. During the first days of fermentation the metabolic activity was very intensive. Sugars, which accounted for 10% of the dry matter, were fermented within 4 d. There were indications, mainly in clover silages, that substances other than water-soluble carbohydrates were used as energy sources.
Low-sugar crops were obtained by shading the fields. After 3 d the sugar in the grass had decreased to half of the original content. This effect was less pronounced in clover. The amount of available substrate and dry matter (DM) content had a major influence on silage quality. In an unwilted crop at least 25 g of water-soluble carbohydrate was needed per kg of fresh material to obtain an acceptable silage quality in the controls, while 20 g was sufficient in inoculated silage. Formic acid addition makes the fermentation less sensitive to water–soluble carbohydrate content. Inoculation of willed silage increased lactic acid production and decreased the pH. There was also less variation in silage quality. 相似文献
20.
J. H. HARRISON R. L. KINCAID K. A. LONEY R. E. RILEY J. CRONRATH 《Grass and Forage Science》1994,49(2):130-137
The effect of adding rolled barley on the ensiling characteristics and nutritive value of lucerne and corn ( Zea mays ) forage was studied using 19-1 plastic mini-silos. Other factors evaluated with lucerne were the effect of wilting and added lactic acid bacteria. Rolled barley was added at rates of 0, 50, 100 and 150gkg−1 (wet weight) to lucerne or corn forage. Lucerne was ensiled at 170–330 g kg−1 dry matter (DM) and lactic acid bacteria were applied at 105 g−1 wet forage. Addition of rolled barley consistently improved the fermentation of lucerne by lowering the pH and decreasing the concentration of acetate and ammonia nitrogen. Wilting of lucerne had variable effects on fermentation in two experiments. The addition of lactic acid bacteria improved fermentation by decreasing the concentrations of acetate and ammonia nitrogen, improved the nutritive value by increasing the in vitro dry matter digestibility (IVDMD), and was associated with decreased amounts of lactic acid. Corn was ensiled at 250 g kg−1 DM, and added rolled barley had little effect on the fermentation of corn silage. The digestibility of all silages determined in vitro was improved by the addition of rolled barley. 相似文献