In vitro degradability of mature and immature leaves of tropical forage legumes differing in condensed tannin and non‐starch polysaccharide content and composition

A study was designed to examine the relationships between protein, condensed tannin and cell wall carbohydrate content and composition and the nutritional quality of seven tropical legumes (Desmodium ovalifolium, Flemingia macrophylla, Leucaena leucocephala, L pallida, L macrophylla, Calliandra calothyrsus and Clitoria fairchildiana). Among the legume species studied, D ovalifolium showed the lowest concentration of nitrogen, while L leucocephala showed the highest. Fibre (NDF) content was lowest in C calothyrsus, L Leucocephala and L pallida and highest in L macrophylla, which had no measurable condensed tannins. The highest tannin concentration was found in C calothyrsus. Total non‐structural polysaccharides (NSP) varied among legumes species (lowest in C calothyrsus and highest in D ovalifolium), and glucose and uronic acids were the most abundant carbohydrate constituents in all legumes. Total NSP losses were lowest in F macrophylla and highest in L leucocephala and L pallida. Gas accumulation and acetate and propionate levels were 50% less with F macrophylla and D ovalifolium as compared with L leucocephala. The highest levels of branched‐chain fatty acids were observed with non‐tanniniferous legumes, and negative concentrations were observed with some of the legumes with high tannin content (D ovalifolium and F macrophylla). Linear regression analysis showed that the presence of condensed tannins was more related to a reduction of the initial rate of gas production (0–48 h) than to the final amount of gas produced or the extent (144 h) of dry matter degradation, which could be due to differences in tannin chemistry. Consequently, more attention should be given in the future to elucidating the impact of tannin structure on the nutritional quality of tropical forage legumes. Copyright © 2003 Society of Chemical Industry     

Influence of dehulling on the apparent metabolisable energy and ileal amino acid digestibility of grain legumes for broilers

BACKGROUND: Removal of hulls may be an effective means of reducing the level of some antinutritional factors and improving the feeding value of grain legumes. Published data on the effects of dehulling on the energy utilisation and amino acid digestibility of grain legumes are limited. This study was designed to investigate the influence of dehulling on the nitrogen‐corrected apparent metabolisable energy (AMEn) and apparent ileal amino acid digestibility of faba beans, Australian sweet lupins and peas for broilers. RESULTS: The non‐starch polysaccharide contents of all three legume species were decreased by the removal of hulls. Dehulling increased (P < 0.05) the content and ileal digestibility of starch in faba beans but had no effect (P > 0.05) on those in peas. Dehulling increased (P < 0.05) the AMEn of faba beans and lupins but had no effect (P > 0.05) on that of peas. Removal of hulls increased the amino acid concentrations in all three legume species, but the apparent ileal digestibility coefficients of most amino acids were unaffected (P > 0.05). CONCLUSION: Dehulling of grain legumes is nutritionally beneficial in view of the improved amino acid concentrations and metabolisable energy values. Copyright © 2010 Society of Chemical Industry     

An assessment of the protein quality and vitamin b content of commonly used fermented products of legumes and millets

Fermented products of legumes, Bengal gram dhal (Cicer arietinum) and green gram dhal (Phaseolus aureus), and millets, bajra (Pennisetum typhoideum), jowar (Sorghum vulgare) and ragi (Eleucine coracana), were analysed for protein quality and vitamin B content. Fermentation reduced total crude protein by 6-8 % in the legume products and 4-6% in the millet products of bajra and ragi. No reduction in crude protein was observed in fermented jowar products. Temperature of batters increased considerably on fermentation, while pH decreased. The protein efficiency ratio (PER) and the true digestibility (TD) of legume products were not altered by fermentation, the biological value (BV) and net protein utilisation, (NPU), of Bengal gram dhokla improved significantly (P<0.05). The TD of fermented jowar increased significantly (P < 0.05) but not that of ragi, bajra and the legume products. BV and NPU of both jowar and ragi products increased significantly on fermentation (P<0.05) but not that of bajra. The thiamin and riboflavin contents of both the legume and millet products increased with increase in fermentation time. Steaming and cooking after fermentation reduced the thiamin and riboflavin content. However, fermentation after cooking of millet batters increased the levels of both vitamins markedly.     

Effects of wilting and mechanical conditioning on proteolysis in sainfoin (Onobrychis viciifolia Scop) wilted herbage and silage

Ensiling legumes allows conservation of high‐quality forage. However, severe protein degradation occurs during ensiling of legumes. A field study was carried out in 1999 on sainfoin (Onobrychis viciifolia Scop) to investigate the effects of wilting and mechanical conditioning on proteolysis in wilted herbage and silage. The herbage was cut with both a rubber roll conditioning machine (C) and with a mower without conditioner (U). It was wilted in the field to three dry matter (DM) levels (220, 330 and 440 g kg^?1) and ensiled in laboratory glass silos. The herbages and the silages were analysed for ensilability characteristics, fermentation quality and nitrogen fractions. During wilting the non‐protein nitrogen (NPN) values increased (p < 0.05) in both U and C treatment. The free amino acid (free AA) values increased (p < 0.05) from 2.4 to 12.9 and from 2.4 to 7.2 mol kg^?1 total nitrogen, in the U and C treatments, respectively. Low wilted silages (DM content <320 g kg^?1) underwent butyric acid fermentation and extensive proteolysis in both treatments, with lower (p < 0.05) NPN and free AA values in the C treatment. Mechanical conditioning may limit protein breakdown and catabolism of some essential amino acids by reducing the field wilting time in both sainfoin wilted herbage and silage. Copyright © 2004 Society of Chemical Industry     

In vitro digestibility of processed and fermented soya bean,cowpea and maize

Tropical legumes, ie soya bean and cowpea, were pre‐treated and subsequently fermented using pure cultures of Rhizopus spp. Impact of soaking, cooking and fermentation of the legumes on their digestibility was determined using an in vitro digestion method. Processing of white maize included, amongst others, natural lactic acid fermentation, cooking and saccharification using barley malt. An in vitro method was standardised to carry out comparative determinations of the dry matter digestibility of cereal and legume food samples as a function of processing conditions, without attempting to exactly mimic gastrointestinal digestion. Using this method based on upper digestive tract digestion, it was observed that digestibility of the legumes increased during cooking and fermentation. Cooking improved the total digestibility of both soya bean and cowpea from 36.5 to 44.8% and from 15.4 to 40.9% respectively. Subsequent fungal fermentation increased total digestibility only by about 3% for both soya bean and cowpea. Digestibility was also influenced by fungal strain and fermentation time. Cooking and subsequent saccharification using malt almost tripled total digestibility of white maize from 25.5 to 63.6%, whereas lactic fermentation of maize had no effect on in vitro dry matter digestibility. Although total digestibility of cooked legumes was only slightly improved by mould fermentation (3% for both soya bean and cowpea), the level of water‐soluble dry matter of food samples increased during fermentation with Rhizopus oryzae from 7.0 up to 27.3% for soya bean and from 4.3 up to 24.1% for cowpea. These fermented products could therefore play a role as sources of easily available nutrients for individuals suffering from digestive disorders. © 2000 Society of Chemical Industry     

Studies on digestibility of selected legume carbohydrates and its impact on the ph of the gastrointestinal tract in rats

A study on the digestibility of legume carbohydrates in unprocessed and processed grain and also in the starch isolated from the grain was carried out by in vitro and in vivo methods. The legumes selected were red gram (Cajanus cajan cv. Hyd. 3A), Bengal gram (Cicer arietinum cv. BEG 482), black gram (Phaseolus mungo cv. T9) and green gram (Phaseolus aureus cv. PS 16). The processes tested were boiling, pressure cooking, roasting, germination, fermentation and parching. The digestibility in vitro was assessed on the basis of maltose released after amylolysis and digestibility in vivo was assessed on the basis of carbohydrate intake and excretion. Digestibilities of the Phaseolus varieties were superior to red gram and Bengal gram. Roasting did not improve the digestibility of any legume as much as boiling and pressure cooking. The digestibility of fermented and germinated legumes was not much higher than the legumes processed by other methods. The increasing order of digestibility in vivo was red gram < Bengal gram < black gram and < green gram. Significant differences were noticed in the digestibility in vivo of moist and dry heat-treated legumes, and between Phaseolus starches and red gram and Bengal gram starch. The pH values of stomach, duodenum and small intestine contents of rats fed legume diets was greater than the pH values at similar sites in rats fed casein protein, whereas the pH values in the caecum of rats fed on legume diets was acidic and that of casein-fed rats was neutral. Caecum weight of rats fed on red gram and Bengal gram diets was significantly higher (P<0.05) than black gram- and green gram-fed groups.     

Effect of lactic fermentation and extrusion of bean and pea seeds on nutritional and functional properties

Controlled lactic acid fermentation of „Bomba”︁ bean and „Opal”︁ pea was used to improved their nutritional and functional properties. The modified legumes were used as a source for extrusion process to obtain snack-type foods. Milled legume seeds were fermented by different population of Lactobacillus plantarum with different moisture content in plant material to estimate the influence of this two parameters on the dynamics of lactic fermentation. Quantitative and qualitative changes in carbohydrates and nitrogen compounds of modified seeds were analyzed (e.g . mono- and oligosaccharides, "in vitro" starch and protein digestibility). In the new snack-type products, functional properties: water solubility index (WSI), water absorption index (WAI), expansion index, bulk density and texture explained as a shearing stress were recorded. Results showed a distinct decrease in raffinose, verbascose and stachyose contents even up to 80 - 90% after fermentation and extrusion process. Lactic fermentation and extrusion of bean and pea seeds contributes to a significant (a ≤ 0,05) increase of "in vitro" protein and starch digestibility. Observations of changes in functional properties of extruderates (e. g., expansion, shearing stress, WSI, WAI) allowed to choose the most efficient model of fermentation pretreatment to obtain the best improvement of nutritional and functional features of the product.     

Production of a yogurt‐like product from Lupinus campestris seeds

A Lupinus campestris milk‐like product was obtained with 6.3% protein by using an alkaline thermal treatment. The colour of the suspension showed a greater similarity to cow's milk than to commercial soymilk. To adjust the carbohydrate concentration and induce fermentation, 3% of sucrose and 1.5% of lactose were added. The product was pasteurized and inoculated with a culture of Streptococcus thermophilus and Lactobacillus delbrueckii ssp bulgaricus. A lupin yogurt‐like product with pH 4.02, 0.87% lactic acid, and a lactic acid bacteria count (3.2 × 10⁸ CFU ml^?1) and viscosity similar to commercial cow's milk yogurt was obtained. The amino acid composition of the proteins in the lupin milk and yogurt products had a good balance, with the exception, as in other legumes, of the sulphur‐containing amino acids. Sensory evaluation indicated that the product was well accepted by consumers. These results offer a good possibility for the utilization of this legume in human nutrition through the elaboration of products that are analogous to others already present in the commercial market. Copyright © 2003 Society of Chemical Industry     

Physico-chemical and acceptability of rabadi (a fermented soya flour product) as affected by cooking and fermentation time

Various food‐processing techniques like malting, roasting, soaking, germination, fermentation, etc. are known to enhance nutritive value and acceptability of different food products. The present study deals with the biochemical analysis and acceptability tests of soya flour rabadi, which was made by fermentation before and after cooking at different time intervals. There was a trend towards increase in moisture, ash, total carbohydrate, calcium, total soluble sugars, reducing sugars, non‐reducing sugars, amylase, glutamate oxaloacetate transaminase enzymatic activities and titrable acidity, whereras a trend towards decrease was found in crude protein, fat, fibre, energy, starch, total phenols and glutamate pyruvate transaminase enzyme activity. Major biochemical changes occurred after 8 h fermentation. In sensory evaluation also, samples fermented for 4 and 8 h after cooking got higher scores than all other samples.     

High apparent ileal digestibility of amino acids in raw and germinated faba bean (Vicia faba)‐ and chickpea (Cicer arietinum)‐based diets for rats

The effects of germinated faba bean (Vicia faba minor var Alameda)‐ and chickpea (Cicer arietinum kabuli var Athenas)‐based diets on performance, N utilisation, amino acid ileal digestibility and plasma concentrations were studied in growing male Wistar rats. Raw and germinated faba bean and chickpea seed meals were incorporated in essential amino acid‐supplemented and energy‐equalised diets as the only sources of protein. A lactalbumin‐based diet equalised in protein (100 g kg^?1) and digestible energy (15.5 kJ g^?1) with the test diets was used as control. Weight gains, gain/feed ratios, N retention and NPU values of animals fed raw or germinated legumes were lower than those of rats given the control (lactalbumin) diet, while faecal dry weights were higher. However, N retention and NPU values of rats fed germinated faba bean diets were higher and faecal dry weights lower than those of animals fed non‐germinated faba bean diets. Liver and thymus fresh and dry relative weights were lower than controls for all legume diets, whilst small intestine, caecum and colon relative weights were higher than controls for non‐germinated faba beans and chickpeas either germinated or not. Caecum and colon fresh and dry relative weights of rats fed germinated faba bean seeds were lower than those of rats fed non‐germinated faba beans and not different from controls. Except for aspartic acid and proline in rats fed raw faba bean diets, apparent ileal digestibilities of amino acids were not different or higher in rats fed legume diets as compared with controls. Except for arginine, apparent ileal amino acid digestibility was higher for germinated than for non‐germinated faba bean seeds. The amounts of glycine, arginine and ornithine in plasma significantly increased whilst those of threonine, alanine, leucine and lysine decreased with respect to controls in faba bean‐ or chickpea‐fed rats, either germinated or not. We conclude that (a) germination of faba bean seeds gave rise to a significant (P < 0.01) but limited improvement in performance, N retention and apparent ileal digestibilities of some amino acids in growing rats compared with non‐germinated seeds, while there was no detectable effect in the case of germinated chickpea seeds, and (b) the apparent ileal amino acid digestibility of essential amino acid‐supplemented diets based on faba bean or chickpea meals, either germinated or not, is similar or even higher than controls. © 2002 Society of Chemical Industry     

Maillard Reaction Products as Encapsulants for Fish Oil Powders

The use of Maillard reaction products for encapsulation of fish oil was investigated. Fish oil was emulsified with heated aqueous mixtures comprising a protein source (Na caseinate, whey protein isolate, soy protein isolate, or skim milk powder) and carbohydrates (glucose, dried glucose syrup, oligosaccharide) and spray‐dried for the production of 50% oil powders. The extent of the Maillard reaction was monitored using L*, a*, b* values and absorbance at 465 nm. Encapsulation efficiency was gauged by measurement of solvent‐extractable fat and the oxidative stability of the fish oil powder, which was determined by assessment of headspace propanal after storage of powders at 35 °C for 4 wk. Increasing the heat treatment (60 °C to 100 °C for 30 to 90 min) of sodium caseinate‐glucose‐glucose syrup mixtures increased Maillard browning but did not change their encapsulation efficiency. The encapsulation efficiency of all heated sodium caseinate‐glucose‐glucose syrup mixtures was high, as indicated by the low solvent‐extractable fat in powder (<2% powder, w/w). However, increasing the severity of the heat treatment of the sodium caseinate‐glucose‐glucose syrup mixtures reduced the susceptibility of the fish oil powder to oxidation. The increased protection afforded to fish oil in powders by increasing the temperature‐time treatment of protein‐carbohydrate mixtures before emulsification and drying was observed irrespective of the protein (sodium caseinate, whey protein isolate, soy protein isolate, or skim milk powder) and carbohydrate (glucose, glucose/dried glucose syrup, or oligosaccharide/dried glucose syrup) sources used in the formulation. Maillard reaction products produced by heat treatment of aqueous protein‐carbohydrate mixtures were effective for protecting microencapsulated fish oil and other oils (evening primrose oil, milk fat) from oxidation.     

Legume‐based fermented foods: Their preparation and nutritional quality

Legume‐based fermented foods are very popular in the Southeast Asia, the Near East, and parts of Africa. They form an appreciable part of daily diet of people as a main source of protein, calories, and certain vitamins. Preparation of legume‐based fermented foods has remained to some extent an art, and their nutritional quality has been of interest to both professionals and layman. The fermentation process helps not only in improving the organoleptic quality of legumes but also enhances nutritional quality. This review examines the production of various legume‐based fermented foods and critically assesses their nutritional quality.     

Evolution of cacao bean proteins during fermentation: a study by two‐dimensional electrophoresis

The protein content of cacao (Theobroma cacao) beans was studied by quantitative two‐dimensional electrophoresis (2‐DE) and by measuring total and protein nitrogen by the Kjeldahl method from the unfermented stage up to the seventh day of fermentation. The major trends in evolution of protein concentration were followed by measuring the intensities of some of the most abundant bean polypeptides. During fermentation a biphasic proteolytic process was observed. Protein degradation was detected after two days of fermentation, and was most pronounced during the third day. Following the initial phase of degradation until the end of fermentation, very little further protein degradation was observed, possibly due to the release of polyphenolic compounds and their subsequent complexing with the remaining proteins. Total protein estimated by the Kjeldahl method decreased to 57% of the initial value during the fermentation period. The process of degradation is selective, with some polypeptides resisting more than others. The evolution of total protein and non‐protein nitrogen content is also described. © 1999 Society of Chemical Industry     

Milk production of dairy goats fed diets with different legume seeds: Effects of amino acid composition of the rumen undegradable protein fraction

BACKGROUND: To establish the effect of the nature of four different legume seeds, lupins (L), faba beans (FB), bitter vetch (BV) and vetch (V) on the production and composition of goat milk, we studied the ruminal degradation of these legumes, and the amino acid (AA) composition of the seeds and that of the undegradable fractions of the protein sources. Four isonitrogenous and isoenergetic diets were designed, and in each case 30% of the protein was supplied by one of the different legume seeds. A group of eight Granadina goats was used to study the utilisation of these diets for milk production. The goats were allocated to a replicated 4 × 4 Latin square. RESULTS: Ruminal fermentation modified the AA profile of the protein of the legume seeds which was different in each case. However, milk production remained unchanged irrespective of the diet consumed. On the contrary, and despite the high level of degradability of the protein in the different legumes, the concentration of total protein, casein (CN) and overall α_S1‐CN and α_S2‐CN in milk depended on the protein source used. CONCLUSION: The concentration of total protein in milk, as well as its composition, was apparently determined by the AA composition of the corresponding fraction of the rumen‐undegradable protein. Copyright © 2008 Society of Chemical Industry     

Water-soluble carbohydrates of tropical pasture grasses and legumes

The soluble carbohydrate composition of the leaves and stems of 5 tropical grass species—Cenchrus ciliaris, Chloris gayana, Cynodon dactylon, Digitaria decumbens and Setaria sphacelata—and 5 tropical legume species—Desmodium intortum, Desmodium uncinatum, Glycine javanica, Phaseolus atropurpureus cv. Siratro and Stylosanthes humilis—has been studied at two stages of growth. Reducing sugars, total soluble sugars, fructosan, starch and pectin have been estimated. Chromatographic analysis of 80% ethanol extracts indicated the absence of the oligosaccharides, raffinose and stachyose, from the leaves and stems of the tropical grass species. They were present in the tropical legumes. None of the tropical grass or legume species were found to accumulate appreciable amounts of fructosan. The carbohydrate storage form in the grass species appeared to be sucrose, with starch of less importance. The carbohydrate storage forms in the legume species appeared to be sucrose, starch and pectin. The nature of the principal carbohydrate storage form appeared to be a characteristic of the species.     

Fermentation technology and quality of sauce prepared from rice dreg protein

Fermented sauce, from rice dreg protein (RDP) instead of soybean, has unique advantages. In the present paper, the fermentation technology of RDP sauce was studied. Amino nitrogen, reducing sugar, soluble protein and colour indicators, as well as the quality of three kinds of RDP sauce fermented under different conditions, were analysed. The results suggest that an optimized fermentation technology is the addition of 2.4 times salty solution into koji, to obtain a 13% salt concentration in the sauce mash, and then fermentation at ~35°C. RDP sauce that had an addition of 0.01% Zygosaccharomyces rouxii in the fermentation stage gave a good quality RDP sauce. The RDP sauce content of amino nitrogen and reducing sugar, with 0.01% Z. rouxii, was 0.98 and 4.57 g/100 mL respectively, and the corresponding sensory quality was better than in the samples produced without Z. rouxii. It was concluded that RDP can be utilized to produce a high‐quality sauce. Copyright © 2015 The Institute of Brewing & Distilling     

Fermentation alters antioxidant capacity and polyphenol distribution in selected edible legumes

This study was designed to investigate the influences of fermentation by naturally occurring bacteria on legumes and lactic acid bacteria on antioxidant capacity and polyphenols in both soluble and bound extracts of eight common edible legumes, including black cow gram, mottled cowpea, speckled kidney bean, lentil, small rice bean, small runner bean and two soya beans. Fermentation had varying effects on the antioxidant capacity of soluble and bound extracts in different edible legumes, with fermented mottled cowpea, speckled kidney bean and small rice bean showing increased total antioxidant capacity. In addition, fermentation in general enhanced total phenolic content in all the selected legumes, which could be associated with the biotransformation between soluble phenolics and the release of bound phenolics induced by micro‐organisms involved in the fermentation process. Phenolic compounds, such as catechin, were increased in fermented mottled cowpea. Overall, fermentation could increase the bioavailability of legume polyphenols and fermented legume powders rich in antioxidant polyphenols can be used to develop novel functional foods.     

Influence of thermal processing on IgE reactivity to lentil and chickpea proteins

In the last years, legume proteins are gaining importance as food ingredients because of their nutraceutical properties. However, legumes are also considered relevant in the development of food allergies through ingestion. Peanuts and soybeans are important food allergens in Western countries, while lentil and chickpea allergy are more relevant in the Mediterranean area. Information about the effects of thermal‐processing procedures at various temperatures and conditions is scarce; therefore, the effect of these procedures on legume allergenic properties is not defined so far. The SDS‐PAGE and IgE‐immunoblotting patterns of chickpeas and lentils were analyzed before and after boiling (up to 60 min) and autoclaving (1.2 and 2.6 atm, up to 30 min). The results indicated that some of these treatments reduce IgE binding to lentil and chickpea, the most important being harsh autoclaving. However, several extremely resistant immunoreactive proteins still remained in these legumes even after this extreme treatment.     

Effect of germination and dehulling on functional properties of legume flours

The functional properties of flours derived from selected legumes were studied before and after dehulling of the germinated seeds. Ungerminated seeds were used as the control. The chosen legumes were green gram (Phaseolus aureus), cowpea (Vigna catjang), lentil (Lens culinaris) and bengal gram (Cicer arietinum). Dehulled samples had a higher protein solubility compared with germinated and control samples. The bulk densities of germinated and dehulled legume flours were lower compared to control. Germination increased water absorption capacities of legume flours from 1226, 1285, 974 and 1362 g kg^?1 to 1481, 1433, 1448 and 1517 g kg^?1 in green gram, cowpea, lentil and bengal gram, respectively. Fat absorption capacities increased in germinated samples (1130, 1242, 920 and 837 g kg^?1) as against 900, 993, 857 and 788 g kg^?1 at ambient conditions for green gram, cowpea, lentil and bengal gram, respectively. On dehulling, the fat absorption capacities of samples were reduced and the differences were statistically significant. The emulsification capacities of control samples ranged from 55 to 193 ml oil emulsified per gram of sample. On germination and dehulling, the emulsification capacities, activities and stabilities of samples increased significantly. There were increases in foaming capacities and reduction in foam stabilities of all the samples investigated on germination and dehulling. Thus, the study indicated that germination and dehulling improved the functional properties of legumes. Copyright © 2006 Society of Chemical Industry     

Biological response to different diets of fermented and unfermented mixtures of flour and cereal brans

The objective of this study was to biologically evaluate eight mixtures of flour and brans prepared with non‐conventional foods popularly denominated ‘multimixtures’, which differed from each other in terms of type of bran (wheat or rice), presence or absence of cassava leaf powder and submission or non‐submission to a solid‐state fermentation with Saccharomyces cerevisiae for 6 h/30 °C, utilising female Wistar/UFPEL rats. Biological indices determined were food efficiency ratio (FER), protein efficiency ratio (PER), net protein efficiency ratio (NPR) and in vivo digestibility. Liver, spleen and kidney specimens were collected at the end of the experiment. In vivo digestibility of diets containing multimixtures formulated with wheat bran was superior to diets containing rice bran, presenting values from 76.5% to 82.8%, which corresponds to up to 85% of casein digestibility. The results allowed the conclusion that fermentation tended to improve food efficiency, but did not influence in vivo digestibility.