Comparative effect of boiling and solid substrate fermentation using the tempeh fungus (Rhizopus oligosporus) on the flatulence potential of African yambean (Sphenostylis stenocarpa L.) seeds

The tropical African yambean (AYB, Sphenostylis stenocarpa L.) is a protein-rich underutilized African legume. The presence of the flatulence- and diarrhoea-causing raffinose family oligosaccharides (RFO: raffinose, stachyose and verbascose) or α-galactosides has limited the food use of African yambean seeds. To reduce this limitation, non-traditional processing methods are required. Seeds of three varieties were (i) examined for the flatulence- and diarrhoea-causing RFO and (ii) fermented with Rhizopus oligosporus for tempeh production. The traditional tempeh production process involved dehulling, soaking in water for 24 h, boiling in water for 30 min, inoculation and fermentation. In addition, the traditional tempeh procedure was modified by using 1% citric acid solution instead of water for soaking and cooking. Comparisons with traditionally cooked beans, which involved boiling in water for 4 h, were made. Boiling seeds for 4 h resulted in 8–30% reduction of total α-galactosides in the three varieties, while the traditional tempeh procedure resulted in an almost complete loss (98%) of the same (P < 0.05). The modified procedure resulted in a bacteria-free tempeh but α-galactoside reduction was 22–39%. Both tempeh production processes were clearly more effective than was traditional cooking in reducing the flatulence potential of the AYB seeds.     

Effect of Processing on Certain Antinutrients in Seeds of Şeker Variety (P. vulgaris L.) Grown in Turkey

Abstract

The effects of different cooking/autoclaving methods were investigated on sucrose, raffinose, stachyose, phytic acid, and tannins content of ?eker bean seeds (Phaseolus vulgaris). All these oligosaccharides and antinutrients decreased under various cooking/autoclaving treatments. Among the different cooking/ autoclaving treatments, 18 h sodium bicarbonate solution soaking followed by autoclaving procedures were the most effective for removing oligosaccharides (65–72%), phytic acid (51%), and tannins (100%). These conditions could be recommended to remove undesirable sugar contents and antinutrients of the ?eker bean used for culinary purposes.     

Effect of soaking and heat processing on the levels of antinutrients and digestible proteins in seeds of Vigna aconitifolia and Vigna sinensis

The effect of soaking, cooking and autoclaving on the levels of total free phenolics, tannins, phytic acid and in vitro protein digestibility (IVPD) were studied in Vigna aconitifolia and Vigna sinensis. Though soaking significantly reduced the content of tannins alone in V. aconitifolia, both total free phenolics and tannins were markedly reduced in V. sinensis. Greater loss of total free phenolics as well as tannins occurred under autoclaving compared to soaking and cooking in both the legumes investigated. In V. aconitifolia, soaking in distilled water for 6 h and cooking for 30 min reduced the phytic acid content by up to 43%. Maximum reduction in the level of phytic acid (36%) was observed under distilled water soaking compared to cooking and autoclaving in V. sinensis. Limited loss in content of phytic acid was noticed under autoclaving compared to soaking and cooking in both the pulses studied. In vitro protein digestibility (IVPD) of V. aconitifolia and V. sinensis was enhanced to 12.5 and 14.8%, respectively, under autoclaving. Of all the processing methods, autoclaving seemed to be the most efficient for reduction in content of the antinutrients, except phytic acid, and improving IVPD in both the pulses.     

Nutritional composition and antinutritional factors of mung bean seeds (Phaseolus aureus) as affected by some home traditional processes

The effects of some domestic traditional processes, such as dehulling, soaking, germination, boiling, autoclaving and microwave cooking, on the nutritional composition and antinutritional factors of mung bean seeds were studied. Germination and cooking processes caused significant (p<0.05) decreases in fat, carbohydrate fractions, antinutritional factors and total ash contents. All processes decreased the concentrations of lysine, tryptophan, threonine and sulfur-containing amino acids. However, all treatments were higher in total aromatic amino acids, leucine, isoleucine and valine contents than the FAO/WHO reference. Dehulling, soaking and germination processes were less effective than cooking processes in reducing trypsin inhibitor, tannins and hemagglutinin activity contents. Also, germination was more effective in reducing phytic acid, stachyose and raffinose. Germination resulted in a greater retention of all minerals compared to other processes. In vitro protein digestibility and protein efficiency ratio were improved by all processes. The chemical score and limiting amino acids of mung bean subjected to the various processes varied considerably, depending on the type of process.     

Effect of processing on antinutrients and in vitro protein digestibility of kidney bean (Phaseolus vulgaris L.) varieties grown in East Africa

The effects of hydration, autoclaving, germination, cooking and their combinations, on the reduction/elimination of antinutrients, flatus-producing compounds and the improvement of in vitro protein digestibility of three selected Phaseolus vulgaris varieties were investigated. Reduction in the amount of total α-galactosides was attained by employing hydration process and was due to the differential solubility of the individual oligosaccharides and their diffusion rates. Due to their heat-sensitive nature, saponins, trypsin inhibitors and phytohaemagglutinins, diminished drastically to undetectable amounts when heating processes (cooking and autoclaving) were employed. Hydration and germination processes were less effective in reducing trypsin inhibitors, saponins and phytohaemagglutinins as compared with cooking/autoclaving processes. Germination process reduced stachyose, raffinose, phytic acid and tannins which was due to metabolic activity. The combination of germination followed by autoclaving processes yielded the most promising result in this study. The bean variety Roba exhibited better protein digestibility on processing and thus has high potential to be used as a raw material for the manufacturing of value-added products.     

Influence of cooking and dehulling on nutritional composition of several varieties of lentils (Lens culinaris)

The effect of cooking and dehulling on nutrients and anti-nutritional factors of several varieties of lentils (Lens culinaris) was investigated. Significant (p < 0.05) variations existed among the lentil varieties with respect to their crude protein, starch, ash, soluble dietary fiber (SDF), insoluble dietary fiber (IDF), total dietary fiber (TDF), resistant starch (RS), trypsin inhibitor activity (TIA), minerals, phytic acid, tannins, sucrose and oligosaccharides (raffinose, stachyose and verbascose) content. Cooking lentils in boiling water significantly increased protein, starch, IDF, TDF, resistant starch, Ca, Cu and Mn content, whereas reduced ash, Fe, K, Mg, P, Zn, TIA, phytic acid, tannins, sucrose and oligosaccharides were observed. Dehulling (removal of seed coat) resulted in a significant increase in protein, starch, resistant starch, K, P, phytic acid, stachyose and verbascose content, however, a significant decrease in SDF, IDF, TDF, Ca, Cu, Fe, Mg, Mn and tannin content was observed.     

Effect of ionizing radiation on antinutritional features of velvet bean seeds (Mucuna pruriens)

Impact of gamma irradiation on the antinutritional constituents of seeds of Mucuna pruriens was assessed on exposing to doses of 2.5, 5.0, 7.5, 10, 15 and 30 kGy. Except for 2.5 kGy, the rest showed significant dose-dependent increase in phenolics. Tannin concentration did not differ significantly up to 7.5 kGy, while it significantly increased at higher doses. Excluding 2.5 kGy, the rest of the treatments showed significant decreases in the phytic acid and complete degradation was attained at 15 and 30 kGy. The l-DOPA concentration showed a dose-dependent decline. A trace amount of hemagglutination activity was seen on human erythrocytes in raw seeds, which was completely absent on irradiation (>5 kGy). Concentration of Polonium-210, a natural radionuclide falls within the admissible limits for consumption. As Mucuna seeds serve as food, feed or as pharmaceuticals, it may be necessary to set the ionizing radiation to a specific dose to retain optimum levels or to eliminate phenolics, tannins, phytic acid and L-DOPA. As irradiation is a physical and cold process, it may be ideal and emerge as an important technique to improve the nutritional or pharmaceutical quality of Mucuna seeds and its products.     

Effect of soaking,cooking and crude α-galactosidase treatment on the oligosaccharide content of red gram flour

The contents of sucrose, raffinose, stachyose, verbascose, total soluble sugars and reducing sugars in whole seeds of 14 cultivars of red gram (Cajanus cajan) grown in Karnataka state were determined. The effects of soaking, cooking and crude α-galactosidase treatment on the levels of the raffinose family of sugars were investigated. The percent losses of raffinose, stachyose and verbascose after soaking the red gram seeds for 16 h were 54.6, 55.4 and 33.3%, respectively. Cooking the red gram seeds for 60 min resulted in a decrease of 80.2% for raffinose, 87.2% for stachyose and 81.6% for verbascose. Thin-layer chromatographic analyses of 4 h enzyme-treated samples revealed complete hydrolysis of galactooligosaccharides. Therefore, α-galactosidase from Cassia sericea could have potential use in the food industry.     

Effect of soaking,dehulling, and cooking methods on certain antinutrients and in vitro protein digestibility of bitter and sweet lupin seeds

Effect of several physical treatments (soaking, dehulling, ordinary cooking, microwave cooking, and autoclaving) on the level of antinutrients and in vitro protein digestibility of bitter and sweet lupin seeds were investigated. The raw bitter and sweet lupin seeds were found to contain phytic acid, tannins, trypsin inhibitor activity, and lectin activity, but α-amylase inhibitor was absent. Dehulling significantly increased the levels of phytic acid (PA), trypsin inhibitor activity (TIA), and tannins, but lectin activity was not changed. Also soaking in bitter (for 96 hr) and sweet (for 24 hr) seeds caused a significant increase in these factors except lectin activity. Cooking methods differently affected the levels of the antinutrients. Thus, PA increased but tannins were not changed, on the other hand TI and lectin activities were inactivated; ordinary cooking and autoclaving were the most effective in both seeds. For combination effect, soaking following cooking treatments significantly decreased PA, tannins, and lectin activity, but increased TIA in both seeds. Moreover, dehulling following soaking and cooking methods resulted in a significant increase of PA, TIA, and tannins. In vitro protein digestibility (IVPD) of raw bitter and sweet lupin seeds were 78.55 and 79.46%, respectively and it was improved by all processing methods; soakingdehulling after autoclaving was the most effective in both seeds. Although some treatments increased the level of antinutrients, they improved IVPD. Therefore, the studied antinutrients are not the only responsible factor for lowering IVPD.     

Reduction of α-galactoside content in red gram (Cajanus cajan L.) upon germination followed by heat treatment

BACKGROUND: Red gram (Cajanus cajan L.) is an important crop for human and animal nutrition. However, raffinose family oligosaccharides present in red gram seed hinder its consumption as it is not digested by normal human carbohydrases and is further fermented by intestinal microflora, which induces flatulence. In order to make the grain legume more amenable for human consumption, we have tried to shed some light on the effect of germination followed by heat treatment methods such as autoclaving, cooking and pressure cooking on the raffinose family of sugars. These techniques, however, are primary prerequisites before consumption of the gram. RESULTS: The percent removal of raffinose, stachyose and verbascose after germinating red gram seeds for 8 h followed by autoclaving was 65.6%, 58.9% and 65.3% respectively; and after cooking was 61.6%, 69.2% and 72.5%. Germinating for 16 h followed by autoclaving led to a mean decrease of 53.3% for raffinose, 60.3% for stachyose and 62.3% for verbascose. Germination of red gram seeds for 16 h followed by cooking led to a mean decrease of 71.7% for raffinose, 76.2% for stachyose and 74.0% for verbascose, respectively. The results for the percent removal of raffinose, stachyose and verbascose after germination of red gram seeds for 16 h followed by pressure cooking was 68.3%, 73.3% and 68.2% respectively. CONCLUSION: This study demonstrates that local methods of processing reduce raffinose family oligosaccharides in red gram. The technique of germinating the seeds for 16 h followed by autoclaving, cooking and pressure cooking for the reduction of raffinose family oligosaccharides is a promising solution to overcome flatulence and increase the overall acceptance of red gram among general populace. Copyright © 2011 Society of Chemical Industry     

Effect of various indigenous processing methods on the α‐galactoside and mono‐ and disaccharide content of an Indian tribal pulse,Mucuna pruriens var utilis

The effect of various treatments, such as soaking in different solutions, cooking of raw and soaked seeds, autoclaving of raw and soaked seeds, dehusking of water‐soaked seeds, fermentation of water‐soaked/dehusked seeds, autoclaving of fermented seeds, dry heating of raw seeds and germination, on the levels of mono‐ and disaccharides and α‐galactosides in two varieties of an Indian tribal legume, mucuna bean (Mucuna pruriens var utilis), was investigated. The levels of raffinose, stachyose and verbascose decreased under various treatments. Among the different soaking and cooking/autoclaving treatments, tamarind pulp extract soaking and sodium bicarbonate solution soaking followed by autoclaving procedures were the most effective for removing α‐galactosides (68.4–70.9 and 68.5–68.9% respectively). The lowest reduction of α‐galactosides (8.4–17.2%) was observed in dry‐heated samples. Germination for more than 72 h resulted in the highest reduction of total α‐galactosides (93.6 and 89.6% in white and black varieties respectively). During the germination process, glucose, fructose and sucrose concentrations increased significantly. © 2001 Society of Chemical Industry     

Antinutritional factors changes occurring in trifoliate yam (Dioscorea dumetorum) tubers after harvest

Studies were conducted on the changes in antinutritional factors occurring during the storage of Dioscorea dumetorum (cv. Yellow) yam tubers. The tubers were harvested and stored under prevailing tropical ambient conditions (19–28 °C, 60–85% RH) for 0, 2, 5, 7, 14, 21, 28, 42 and 56 days. The samples were evaluated for total phenols, tannins, phytic acid, α-amylase inhibitors, trypsin inhibitors and oxalates. Results showed that, during storage, total phenols and tannin contents decreased by approximately 22–28% after 56 days of harvest, due to the hardening phenomenon and sprouting. Phytate and α-amylase inhibitor levels declined, respectively, from 690–416 mg/100 g and 1013–659 AIU/g, while oxalates and trypsin inhibitor contents increased during the first week of storage (days 0–7) and, after this period, they started to decrease progressively. Since sprouting of most tubers was observed after 28 days of storage, the results suggest that post-harvest hardening and sprouting influence antinutritional composition of D. dumetorum tubers.     

Effect of soaking,germination, cooking and fermentation on antinutritional factors in cowpeas

The present work deals with the study of efficacy of some treatments, namely soaking (in water and bicarbonate solution( ordinary and pressure cooking, germination and fermentation in reducing or removal of antinutritional factors usually present in cowpeas (protease inhibitors, tannins, phytic acid and flatus‐producing oligosaccharides (raffinose and stachyose). The results showed that long‐time soaking (16 h) in bicarbonate solution caused remarkable reduction in the antinutritional factors. Pressure cooking was more effective than ordinary. Cooking pregerminated cowpeas was most effective. Fermentation completely removed trypsin inhibitor, oligosaccharides and reduced remarkably phytic acid. However, tannins noticeably increased.     

Effect of soaking,germination, cooking and fermentation on antinutritional factors in cowpeas

The present work deals with the study of efficacy of some treatments, namely soaking (in water and bicarbonate solution), ordinary and pressure cooking, germination and fermentation in reducing or removal of antinutritional factors usually present in cowpeas (protease inhibitors, tannins, phytic acid and flatus-producing oligosaccharides (raffinose and stachyose). The results showed that long-time soaking (16 h) in bicarbonate solution caused remarkable reduction in the antinutritional factors. Pressure cooking was more effective than ordinary. Cooking pregerminated cowpeas was most effective. Fermentation completely removed trypsin inhibitor, oligosaccharides and reduced remarkably phytic acid. However, tannins noticeably increased.     

Oligosaccharides, Antinutritional Factors, and Protein Digestibility of Dry Beans as Affected by Processing

Dry beans (Phaseolus vulgaris) were subjected to soaking, cooking or a combination of both prior to fermentation, and then assessed for oligosaccharides, antinutritional factors and in-vitro protein digestibility. Results showed an important decrease in raffinose oligosaccharides and antinutritional factors. However, an increase of trypsin inhibitor and tannin contents occurred respectively in cooked or soaked-cooked fermented beans and in raw or soaked fermented beans. Appreciable improvement in in-vitro protein digestibility was only observed in cooked or soaked-cooked beans. After fermentation, the largest decreases were observed in soaked-cooked beans (92.75%) for raffinose, in cooked beans (31.57%) for phytic acid, in soaked beans (90.86%) for stachyose, and in raw beans for trypsin inhibitor (38.77%). The highest increase due to fermentation was observed in raw beans for in-vitro protein digestibility (1.73%).     

Determination of oligosaccharide contents in 19 cultivars of chickpea (Cicer arietinum L) seeds by high performance liquid chromatography

The extraction procedure of oligosaccharides from chickpea seeds was optimized and sufficient extraction was achieved with 50% of ethanol-water in a ratio of 10:1 for solvent to defatted chickpea meal at 50 °C for 30 min. Under the optimal extraction conditions, the contents of oligosaccharides in 19 cultivars of chickpea seeds were determined by HPLC. The results showed that the main α-galactooligosaccharides (α-GOS) in chickpea seeds were raffinose, stachyose, verbascose and an unknown glycoside, which was isolated, purified, and identified as ciceritol. Ciceritol, the main sugar in all the chickpea samples, accounted for about 50% of the total α-GOS. There were considerable variations in the levels of α-GOS and sucrose between species, especially verbascose which could only be detected in 7 samples. With the highest amount of α-GOS and a low amount of sucrose, the 171 was the best choice for obtaining α-GOS for use as a prebiotic in functional foods.     

Nutritional quality of legume seeds as affected by some physical treatments 2. Antinutritional factors

Raw and treated cowpea, pea and kidney bean seeds were investigated for their content of antinutritional factors including tannins, phytic acid, trypsin inhibitors and oligosaccharides. Treatments applied included water soaking, boiling, roasting, microwave cooking, autoclaving, fermentation and micronization. Kidney bean contained the highest antinutrient content among all investigated seeds. The least tannins and phytic acid contents were recorded in Canadian cowpea while Canadian pea showed the lowest TIA. All treatments conducted caused significant decreases in tannins, phytic acid, TIA and oligosaccharides as compared to the raw seeds. Boiling caused the highest reduction in tannins followed by autoclaving and microwave cooking. Autoclaving and fermentation were the most effective in reducing phytic acid content. Heat treatments (boiling, roasting, microwave cooking and autoclaving) brought a total removal of trypsin inhibitors of all samples. Furthermore, autoclaving caused the highest reduction in oligosaccharides followed by fermentation while the least reductions were caused by either roasting or micronization with no significant difference between these two treatments.     

The impact of dehydration process on antinutrients and protein digestibility of some legume flours

Dehydrated foods are specially designed for patients with mastication or/and deglutition problems. This study has assessed the effects of soaking, cooking and industrial dehydration treatments on antinutrient factors and also on protein digestibility in legume flours (chickpea, lentil and bean). A general decline of phytic acid was observed during dehydration, being the most accentuated in case of lentil (44%), followed by white beans and pink-mottled cream beans. Beans were the legumes that showed the highest levels of enzyme inhibitors and lectins, however processing such as cooking and dehydration significantly reduced (p < 0.05) their levels further to negligible concentrations. The dehydration did not cause further effects than ordinary cooking in reduction of the concentration of polyphenolic compounds of flours. However, a higher increase of in vitro protein digestibility (IVPD) was produced by dehydration in all legumes from 12% to 15%. Thus, dehydrated legume flours could be considered ready-to-use for special meals to specific populations.     

Hydrolysis of oligosaccharides in soybean products by Debaryomyces hansenii UFV-1 α-galactosidases

α-Galactosides are abundant sugars found in legumes such as soybean. Since humans and monogastric animals lack α-galactosidase in the digestive tract, they are unable to digest these sugars, which induce flatulence. The use of α-galactosidases is promising as a means to overcome this problem, and to increase the consumption of soy products. Immobilized α-galactosidase, derived from Debaryomyces hansenii UFV-1, exhibited an activity of 40 U per g of silica and an activity yield of 50%. The optimum pH of free and immobilized α-galactosidase was 5.0 and the optima temperatures were 60 and 80 °C, respectively. The soymilk stachyose was completely hydrolyzed by different enzyme forms after incubation for 4 h at 60 °C, while raffinose was reduced by 100%, 25% and 68% by free, immobilized enzymes and permeabilized cells, respectively. The soy molasses treatment with free enzyme for 6 h promoted reduction in stachyose and raffinose contents by 100% and 50%, respectively.     

Levels of nutritional constituents and antinutritional factors in black gram (Vigna mungo L. Hepper)

A study was conducted on nutritional constituents (total sugars, total proteins, total lipids and starch content) and antinutritional factors such as phenolic compounds, tannins, saponins, phytic acid, trypsin inhibitors and enzymes related to them such as acid- and alkaline phosphatases, ??-galactosidase in eleven recommended cultivars and twenty one advance breeding lines of black gram (Vigna mungo L. Hepper) with an aim to identify genotypes containing high nutritional quality and low antinutritional content. The average content of starch, total soluble sugars, proteins and lipids was around 43.5, 4.84, 22.0 and 1.1%, respectively. Seven genotypes had higher levels of bound fructose contributed by sucrose and raffinose series oligosaccharides. A significant positive correlation was observed among total phenols, o-dihydroxy phenols and flavonols; and among trypsin inhibitors and saponins. The content of phytic acid and activity of trypsin inhibitors showed significant variation among these genotypes. However, not much variation was observed in the content of tannins and saponins. Activities of ??-galactosidase, acid- and alkaline phosphatase were found to be related to the content of bound fructose of raffinose series oligosaccharides and phytic acid respectively. Genotypes having higher activity of these enzymes showed lower content of these antinutritional factors. The results showed that the observed diversity in developed cultivars and advance breeding lines could be further used by plant breeders.