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1.
Purified and semi-purified polysaccharides characteristic of cereals were fermented in vitro with a pig faecal inoculum, using the cumulative gas production technique, to examine the kinetics and end-products of fermentation after 48 h. It was shown that arabinoxylan and mixed linkage (1,3;1,4) β-glucan were rapidly fermented if soluble, while less soluble substrates (insoluble arabinoxylan, maize and wheat starch granules, and bacterial cellulose) were more slowly fermented. Relevant monosaccharides were fermented at very similar rates to soluble polymeric arabinoxylan and β-glucan, showing that depolymerisation was not a limiting step, in contrast to some previous studies. Bacterial cellulose is shown to be a useful model substrate for fermentation of plant cellulose which is difficult to obtain without harsh chemical treatments. Fermentation end-products were related to kinetics, with slow carbohydrate fermentation resulting in increased protein fermentation. Ratios of short-chain fatty acid products were similar for all arabinoxylan and β-glucan substrates.  相似文献   

2.
The effect of dehulling, soaking and soaking/cooking on sucrose, raffinose and stachyose in mature dry seeds of nine varieties of cowpea (Vigna unguiculata) and one variety of tropical African yam bean (Sphenostylis stenocarpa) were investigated. The results showed a progressive decrease in sucrose, raffinose, and stachyose contents. Soaking for 12 hours and cooking for 30 min eliminated most of the sucrose, raffinose and stachyose. The sugar contents in whole raw cowpea were sucrose 0.73–4.58%, raffinose 0.71–6.86% and stachyose 2.38–3.87%, and for tropical African yam bean sucrose 4.08%, raffinose 1.08% and stachyose 4.14% while the seeds soaked for 12 hours and cooked for 30 min had for cowpea sucrose 0.03–0.81%, raffinose 0.04–0.20% and stachyose 0.12–0.72%, and tropical African yam bean sucrose 0.70%, raffinose 0.40% and stachyose 0.41%.  相似文献   

3.
The oligosaccharide content was determined in 12 different cultivars of black gram. The effect of various treatments such as soaking, cooking, and enzyme treatment on the raffinose family oligosaccharides of dry seeds and flour was studied. Ajugose, a higher oligosaccharide (DP 6) found in trace quantities in seeds, was shown in black gram by HPLC. The percent reduction of raffinose, stachyose, verbascose, and ajugose after soaking for 16 hr was 41.66%, 47.61%, 28.48%, and 26.82%, respectively in Local-I variety and 43.75%, 20.58%, 23.60%, and 15.88%, respectively in Local-II variety. Cooking for 60 min resulted in decrease of 100% for raffinose, 76.19% for stachyose, 36.39% for verbascose, and 60.97% for ajugose in Local-I variety and 100% for raffinose, 55.88% for stachyose, 48.52% for verbascose, and 56.07% for ajugose in Local-II variety. Thin layer chromatographic analysis of 3 hr enzyme-treated samples revealed almost complete hydrolysis of raffinose family of oligosaccharides. Among the different methods employed, enzyme treatment was found to be the most effective for removing α-galactosides in black gram.  相似文献   

4.
Anti-nutritional factors of developing seeds and pod walls of fenugreek were evaluated which affect their nutritional value. Sucrose, raffinose and stachyose decreased with maturity of seeds in all the cultivars. Total, non-reducing sugars increased and reducing sugars decreased at maturity in all the cultivars. The reducing sugars decreased with maturity of pod walls. The flatus producing sugars were maximum in PEB pod walls. Saponin content increased towards maturity of seeds but decreased at maturity of seeds and decreased at maturity in pod walls of all cultivars. Phytate increased with seed maturity up to 95 days after anthesis, while phytate decreased in pod walls of all the cultivars with maturity. Total phenol, catechol and flavonol decreased with advancement of pod wall development. Total phenol decreased except HM 46 a maturity of seeds.  相似文献   

5.
The identity and quantity of and effect ofprocessing on raffinose oligosaccharides in raw,mature seeds of lima beans (Phaseolus lunatus),pigeon peas (Cajanus cajan), African yam beans(Sphenostylis sternocarpa) and jackbeans (Canavalia ensiformis) were investigated. Sucrose,raffinose, stachyose and verbascose were identified byHPLC in all the legume seeds. The total-galactoside contents of the seeds in decreasing order were African yam beans3.84 mg/100 mg; white lima beans 3.62 mg/100 mg; creampigeon peas 3.51 mg/100 mg; red lima beans3.37 mg/100 mg; jackbeans 2.83 mg/100 mg and brownpigeon peas 2.34 mg/100 mg. The predominantoligosaccharide was verbascose in pigeon peas andstachyose in the other three legumes. Cooking unsoakedseeds brought about a greater reduction in the total-galactoside content than soaking for ninehours. The removal of oligosaccharides was higher inlegumes cooked in alkaline solution than in water.Germination quantitatively reduced raffinose,stachyose and verbascose while sucrose was increasedin all seeds except red lima beans and jackbeans.  相似文献   

6.
Oligosaccharides were the most abundant carbohydrates in the unfermented African locust beans. Flatus-forming oligosaccharides — stachyose, raffinose and sucrose — were the main constituents. During the first 24 h of fermentation, the quantities of the oligosaccharides decreased significantly. The reducing sugars increased during the first 12 h of fermentation but then decreased. The reducing sugars detected in the unfermented and fermented locust beans were similar; these were galactose, glucose and fructose. The activities of α-galactosidase were highest at 24 h from the start of fermentation while the peak of sucrose activity was at 36 h.  相似文献   

7.
African locust-bean (Parkia filicoidea Welw) seeds were allowed to ferment under natural conditions and the chemical changes occurring during the fermentation were studied. Chemical analysis of fermented and unfermented beans showed a marked decrease in the total sugar content; crude and true protein levels all increased. The results of the chemical analyses indicate that fermentation resulted in protein enrichment of the fermented locust bean (daddaw). Fermentation also imparts a characteristic flavour and odour to the beans.  相似文献   

8.
The study was aimed at investigating the nutrient and tannin composition of fermented legume seeds (oil bean, castor oil bean and African locust bean) used as food condiments in Nigeria. The legume seeds were purchased from local retailers, cleaned and subjected to varied fermentation periods. Standard assay techniques were adopted to analyze the parameters selected for use. The 4-day fermentation period caused the highest increases in protein and tannin and decreases in ash, lipids and non-protein nitrogen (NPN). The pulp of African locust bean had more protein an ash and the oil bean seeds less lipids and NPN. Fermentation times had varied effects on mineral levels. Fermentation for 4 d increased zinc, sodium and phosphorus except sodium for the African locust bean. The pulp had lower Zn and phosphorus than the seed. Fermentation for 4 d offers a greater advantage over other periods for production of nutritious and cheap food condiments in Nigeria.  相似文献   

9.
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   

10.
A common bean variety, grown in Burundi, was either fermented, soaked and/or cooked, and then assessed for nutrient composition, in-vitro starch digestibility and protein nutritive value. A decrease in ash, most minerals, vitamins, and some essential amino acids was noted for soaked, cooked and soaked-cooked beans. Compared to untreated beans, soaking decreased soluble sugar (9.8 percent) but increased starch (7.3 percent) and soluble fiber (16.9 percent). In cooked beans, an increase in soluble sugar (1.5 percent), and a decrease in thiamine (81.7 percent), starch (24.6 percent) and soluble fiber (16.6 percent) and nitrogen (2.9 percent) contents were observed. Crude fiber (6.9 percent) and starch (10.0 percent) increased while fat (17.6 percent), fatty acids (linoleic: 10.7 percent; linolenic: 14.3 percent) and soluble sugars (25.4 percent) and nitrogen (14.4 percent) decreased in soaked-cooked beans. Fermentation increased potassium (11.6 percent), soluble fiber (18.9 percent), and some amino acids but decreased fatty acids (linoleic: 13.5 percent; linolenic: 19.9 percent), soluble sugar (75.2 percent) and vitamin (riboflavin: 41.0 percent; niacin: 24.5 percent) contents in common beans. However, the in-vitro starch digestibility was greatly improved (12.3 percent) by cooking while it decreased in soaked beans (29.2 percent). Soaking-cooking and fermentation did not have any significant effect on the digestibility of common bean starch. Finally, among the five treatments applied to common beans, only fermentation showed a significant improvement (8.3 percent) on the protein nutritive value of this legume.  相似文献   

11.
Antinutritional factors of anasazi bean were compared to traditional pinto bean (Phaseolus vulgaris L.). Anasazi beans contained less (p<0.001) soluble and bound condensed tannins compared to pinto beans. No differences (p>0.05) in stachyose and raffinose content were found between the two bean types; verbascose was not detected at all. Significant (p<0.05) differences in lectin content were observed between anasazi and pinto bean. The lectins of anasazi beans were classified as non toxic and those of the pinto beans as toxic types. No differences (p>0.05) in inhibitor activity against human and bovine trypsin and chymotrypsin were found between the two bean types.  相似文献   

12.
The objective of this project was to determine the effect of various types of processing on selected nutrition related parameters of commonly consumed Indian pulses and soybean. Germination reduced the phytic acid content of chickpea and pigeonpea seeds by over 60%, and that of mung bean, urd bean, and soybean by about 40%. Fermentation reduced phytic acid contents by 26–39% in all these legumes with the exception of pigeonpea in which it was reduced by more than 50%. Autoclaving and roasting were more effective in reducing phytic acid in chickpea and pigeonpea than in urd bean, mung bean, and soybean. Germination and fermentation greatly increased the in vitro protein digestibility (IVPD). IVPD was only slightly increased by roasting and autoclaving of all legumes. Germination and fermentation also remarkably decreased the total dietary fiber (TDF) in all legumes. Autoclaving and roasting resulted in slight increases in TDF values. All the processing treatments had little effect on calcium, magnesium and iron contents.  相似文献   

13.
Five cultivars of bambara groundnut were selected on which to study the effects of germination and fermentation on their proximate composition. The cultivar that had the highest protein content was chosen to prepare unfermented and fermented milk. Standard assay techniques were adopted to determine the parameters selected for use. Germination caused a decrease in the protein, carbohydrate and starch; it increased sugar content, and had varied effects on the lipids contents of the dry samples. The anti-nutritional factor-tannin concentration was decreased. Germination and fermentation had varied effects on the nutrient compositions of the milk. Compared to the control, germination had the same effect as in the seeds. Fermentation further decreased some of the nitrogenous constituents, sugar and starch content of the milk and much more drastically the tannin content. Hydrolysis and other metabolic changes freed the nutrients from their bound forms while decreasing the quantity, but increasing the quality and availability of the nutrients.  相似文献   

14.
Both the pericarp and the unripe seeds of the unripe fruits ofGlossonema edule were separately analysed. The crude protein content of the unripe seeds is double that of the pericarp. Investigation of the amino acids of both parts revealed slight quantitative differences with chemical scores of 40, 40 for each of methionine and tryptophan and 65 for lysine. The ratio of essential total: amino acid averages 34.5, compared to a corresponding value of 47.4 for the reference egg proteins. The analysis of the fatty acids showed that the ratio of saturated to non-saturated fatty acids averaged 73:27; palmitic acid makes up 60% of the total fatty acids. The soluble carbohydrate content of the pericarp is slightly higher than the corresponding value in the unripe seeds. Paper chromatography of the free sugars of both parts revealed qualitative differences. The oligosaccharide reffinose was detected in both parts. The ash was analysed for its content in four trace minerals: iron, zinc, manganese and copper.  相似文献   

15.
Effects of soaking, cooking and autoclaving on changes in polyphenols, phytohaemagglutinating activity, phytic acid, hydrogen cyanide (HCN), oligosaccharides and in vitro protein digestibility were investigated in seeds ofDolichos lablab var.vulgaris. Both distilled water and NaHCO3 solution soaking and autoclaving significantly reduced the contents of total free phenolics (85–88%) compared to raw seeds. Autoclaving (45 min) reduced the content of tannins by upto 72%. Soaking seemed to have limited effect in eliminating phytohaemagglutinating activity, whereas autoclaving (45 min) seemed to eliminate the haemagglutinating activity completely. The reduction in content of phytic acid was found to be some what greater in distilled water soaking (28%) compared to NaHCO3 solution soaking (22%). Only a limited loss in content of phytic acid was observed under cooking as well as autoclaving. Loss of HCN was greater under autoclaving (87%) compared to the other processes studied. Of the three sugars analysed, soaking reduced the level of verbascose more than that of stachyose and raffinose. Autoclaving reduced the content of oligosaccharides more efficiently (67–86%) than ordinary cooking (53–76%). Autoclaving improved the in vitro protein digestibility (IVPD) significantly (13%). Of all the different water and hydrothermal treatments studied autoclaving seemed to be the most efficient method in improving IVPD and eliminating the antinutrients investigated except phytic acid.  相似文献   

16.
The oligosaccharide profile of raw mature seeds of seven different legumes indigenous to the Philippines was measured in 70% ethanol extracts of the seeds by thin layer chromatography using HPTLC plates and quantified by a densitometer. Based on the results, the legumes could be ranked according to decreasing oligosaccharide content or flatulence potential as follows: Sam-samping (Clitoria ternatea)>hyacinth bean (Dolichos lablab)> sabawel (Mucuna pruriens)>lima bean (Phaseolus lunatus)>swordbean (Canavalia gladiata)>rice bean (Vigna umbellata)>jack bean (Canavalia ensiformis). Sam-samping had 4.79% total oligosaccharides and hyacinth bean or batao, 3.66%. A jack bean accession had 1.79% oligosaccharides.Simple processing methods were tested to detoxify the oligosaccharides. Soaking the batao seeds had no effect while boiling even resulted in a net 23–31% increase in the levels of raffinose, stachyose and verbascose. On the other hand, two min of dry roasting resulted in complete removal of oligosaccharides whereas germination resulted in about 30–40% decrease after 1 and 2 days, respectively.Part of MS thesis of the senior author.  相似文献   

17.
提高红碎茶水溶性多酚类保留量实验   总被引:4,自引:1,他引:3  
研究了红碎茶发酵过程中茶多酚、此茶素的变化规律,结果表明,茶多酚、儿茶素总量随发酵时间的延长而降低,发酵温度控制在23℃、发酵时间在100min最有利红碎茶品质。在发酵中添加2%的柠檬酸钠等化学抑制剂和胰蛋白酶等生化抑制剂可明显提高成茶中茶多酚、儿茶素的保留量,增加条黄素、茶红素的含量和降低条褐素的含量。  相似文献   

18.
The effects of processing (soaking, dehulling, fermentation and heat treatment) on the cooking time, protien, mineral, tannin, phytate and in vitro protein digestibility (IVPD) of the african yambean (AYB) were examined. The cooking time ranged from 90–155 minutes. Soaking reduced cooking time by about 50 percent. Soaking for 12 hours was the most appropriate to reduce cooking time, tannin and phytate levels. It improved in vitro protein digestibility (IVPD). Prolonged soaking (24 hours) decreased calcium (Ca) and iron (Fe) values by 19 percent and 35 percent, respectively. Dehulling showed that Ca, Fe, magnesium (Mg) and zinc (Zn) were concentrated in the seed coat of the AYB. The seeds soaked and dehulled retained Mg and Zn. Dehulling reduced tannin but had no significant effect on phytate and the IVPD of the AYB except for seeds soaked for 12 hours before dehulling. Soaking for 24 hours before dehulling significantly increased crude protein content by 16 percent (p<0.05). Blanching and roasting increased the IVPD by 8–11 percent. Fermentation had no effect on the crude protein, Ca, Fe, Mg and Zn but significantly reduced phytate content of the AYB. Fermentation had no advantage over heat treatment with respect to improving the in vitro protein digestibility of the AYB.  相似文献   

19.
为了解影响油菜种子含油量的关键基因,从高含油量(HO)和低含油量(LO)甘蓝型油菜中克隆了5个脂 酰-ACP硫酯酶(fatty acyl-ACP thioesterase, FAT)的基因。序列分析表明这5个FAT 基因在HO和LO油菜基因组之 间没有序列差异。5个FAT 基因分别命名为:BnaA.FATA.a、BnaC.FATA.b、BnaA.FATA.c、BnaC.FATB.a 和BnaA.FATB. b。分析表明,HO种子中5个FAT 基因的表达水平显著高于LO种子。异源表达结果显示,5个FAT 基因的所有酵母 转化子的含油量均显著增加,并且它们的脂肪酸组成均发生了变化。将这5个FAT 基因转化到拟南芥中进行进一 步的功能分析。5个转基因材料T1种子含油量均显著增加;BnaA.FATA.a、BnaC.FATA.b、BnaA.FATA.c 转基因株系中 的饱和脂肪酸含量显著降低,而不饱和脂肪酸含量均显著增加;相反,在BnaC.FATB.a 和BnaA.FATB.b 转基因材料 中,饱和脂肪酸含量显著增加,而不饱和脂肪酸含量显著降低。结果表明,这5个FAT 基因不仅可以增加拟南芥含 油量,而且可以改变脂肪酸组成比例。  相似文献   

20.
用乙烯利和NaCN预处理花生种子,实验结果表明:(1)乙烯和CN-都提高种子子叶的抗氰电子传递速率,同时乙烯还提高种子子叶的总呼吸速率以及EMP-TCA速率,CN-则降低种子子叶的总呼吸速率以及EMP-TCA速率。(2)乙烯提高种子子叶的蛋白酶、脂肪酶和过氧化氢酶活性并提高游离氨基酸和脂肪酸含量以及降低水溶性蛋白质含量;CN-则降低种子子叶的蛋白酶、脂肪酶和过氧化氢酶活性,并降低游离氨基酸和脂肪酸含量,但提高水溶性蛋白质含量。(3)乙烯提高暗萌发苗的单株鲜重,CN-则降低暗萌发苗的单株鲜重。   相似文献   

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