α-Amylase inhibitor levels in seeds generally available in Europe

The α-amylase inhibitor (αAI) levels in 18 seeds, which are generally available throughout Europe, have been determined. Kidney beans, haricot beans, pinto beans and runner beans had high contents of αAI (2–4 g equivalent kg^?1 seed meal). Butter beans, blackeyed peas, chickpeas, field beans and sweet lupinseeds contained 0.1–0.2 g inhibitor equivalent kg^?1 seed meal. No αAI activity was detected in samples of adzuki bean, lentils, mung beans, peas, soya beans, sunflower seeds or winged beans. The αAI activity present in whole kidney beans was relatively heat-resistant. However, it could be completely abolished by aqueous heat treatment of fully imbibed beans at 100°C for 5–10 min.     

Subtilisin inhibitors from legume seeds: A purification procedure

Subtilisin inhibitors were prepared from ethanol-acetone precipitated seed extracts of chick peas, jack beans and broad beans, heated to destroy endogenous proteases. Trypsin inhibitors were complexed with trypsin and separated from subtilisin inhibitors by molecular sieve chromatography. The eluates were again heated to avoid tryptic degradation. The procedure was easy to handle and gave satisfactory yields. In a final step two subtilisin isoinhibitors from chick peas were purified to electrophoretic homogeneity. They constitute 0.01% of the defatted dry weight.     

Nutritive value of some improved varieties of legumes.

The nutritional quality of some improved varieties of chick peas (Cicer arietinum), mash beans (Phaseolus mungo), mung beans (Phaseolus aureus) and cow peas (Vigna sinensis), grown in Pakistan, was measured chemically (including amino acid analyses) and biologically in N-balance experiments with growing rats. Lysine and total sulphur amino acids were lowered in varieties with a higher content of protein. The true protein digestibility (TD), biological value (BV) and net protein utilisation (NPU) of different varieties of chick peas, mung beans and cow peas varied between 85–89, 83–85 and 87–92%, 62–69, 54–56 and 55–59% and 55–60, 45–48 and 50–51%, respectively. The TD of protein was highest (89%) in chick peas, 6560 having a higher protein content (29.4%) while its BV was lowest (62%) as compared to the other varieties of chick peas. There was a significant correlation (r=0.97) between BV and the total sulphur containing amino acids and BV could be predicted from the regression equation; BV (%)= 33.03 + 10.56x methionine+cystine (g per 16 g N). This indicates that methionine+cystine are the first limiting amino acids in these varieties. Tannin content does not seem to affect the TD of mash and mung beans.     

The effect of storage of canned vegetables on concentration of the metals Fe, Cu, Zn, Pb, Sn, Al, Cd and Ni

The increase in the concentration of Fe, Cu, Zn, Pb, Sn, Al, Cd and Ni over a 2 year's time of strongly corrosive acidic vegetables (pickles) and weakly corrosive vegetables (peas, green beans, haricot beans, mushrooms) has been determined. The results show a considerable increase in Fe, Cu, Pb and Sn content with time, particularly for pickles, while the change in Al, Cd, Zn and Ni content was rather negligible.     

The polyphenolic content and enzyme inhibitory activity of testas from bean (Vicia faba) and pea (Pisum spp.) varieties

The polyphenolic content of the testa of two coloured flower varieties of beans grown in Wales was comparable with that of two coloured flower varieties of peas grown in eastern England. Testa tannins from both species had the same adverse effect on protein solubility, the inclusion of 15% testa producing a 7 unit reduction in protein solubility in 5% saline solution. Water extracts prepared from the testas also significantly inhibited in vitro the activities of trypsin, α-amylase and fungal cellulase, and in all cases enzyme activity was restored on the addition of polyvinyl pyrrolidone, clearly indicating that the observed inhibition was due to the presence of tannins. Analysis of the whole grain revealed that, due to differences in the proportion of testa (approximately 13% in beans as compared with 10% in peas), peas had a significantly lower overall polyphenolic content. However, it is concluded that pea testa tannins may be of equal significance to bean tannins in animal diets since the formulation of isonitrogenous diets would require a greater proportion of peas due to their lower protein content.     

Legume Processing Effects on Dietary Fiber Components

Effects of different processes were studied on neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose, and lignin content of legumes. Chick peas, kidney beans, and lentils were soaked and cooked, simulating home processing. Values were recorded on a wet basis as a guide to calculating their contribution to the diet. Decrease in values was more pronounced in pressure-cooked chick peas and kidney beans with cooking liquid removed. In lentils, cooking liquid embedded, no difference between processes was observed. Amounts of dietary fiber components on a dry basis, of interest when legume meal is used as food supplement, increased for chick peas and beans, except for the hemicellulose of beans and lentils, which decreased.     

Saponins and sapogenins of chick pea,haricot bean and red kidney bean

The saponins of red kidney bean (Phaseolus vulgaris), chick pea (Cicer arientinum) and haricot bean (Phaseolus vulgaris) all contain soyasapogenol B as the only aglycone. The levels of soyasapogenol B estimated were: chick pea, 0·075%; haricot bean, 0·149%; and red kidney bean, 0·102%; on a defatted, dry weight basis. HPLC separation of the saponin preparations indicates the presence of at least five saponins in red kidney bean, five in haricot bean and two in chick pea. Retention time comparison of the saponin preparations indicates the possible presence of soyasaponin I in all three legumes and soyasaponin II in haricot and red kidney beans.     

Effects of micronising on the utilisation of field beans (Vicia faba L.) by the young chick

The major changes in the composition of field beans (Vicia faba L.) caused by micronising were as follows: the moisture content was reduced from 16.5 to 13.2%, the trypsin inhibitor activity reduced from 2.49 to 0.21 trypsin inhibitor units/mg dry matter and the available carbohydrate content raised from 40.6 to 50.2%. Growth and food consumption of broiler chicks from 1 to 2 weeks of age were not affected significantly when micronised beans replaced raw beans in their diets at a level of 300 g/kg. However, food conversion efficiency, apparent dry matter digestibility and nitrogen retention were significantly improved and pancreas size significantly reduced when the birds were fed the diet containing the micronised beans. The nitrogen-corrected metabolisable energy (m.e.) of the diet containing 500 g of micronised beans/kg (10.88 MJ/kg) was significantly higher than that of a diet containing 500 g of raw beans/kg (10.33 MJ/kg). It was calculated that the m.e. of the beans had been raised from 10.59 to 11.67 MJ/kg dry matter by micronisation. The improvement in nutritive value is attributed partly to the destruction of the trypsin inhibitor and partly to the increased availability of the carbohydrate fraction of the beans.     

Protein quality of germinated Phaseolus vulgaris

Advantages of seed germination consist of an increase in the bioavailability of proteins as well as the change in the antinutritional factors which limit their utilization. Throughout this work, the effects of germination and cooking after germination on the protein in black and white beans (Phaseolus vulgaris) were evaluated. Antinutritional factors that affect the utilization of such protein were also assessed. The amounts of protein, available lysine, tannins, PER, and protein digestibility in vitro and apparent, of beans germinated and germinated-cooked were quantified. The germination significantly (p≤0.05) increased the content of proteins, inactived trypsin inhibitors, and raised the available lysine. Germination and cooking completely inactivated the trypsin inhibitors, which became lysine less available, decreased tannins, and increased protein digestibility and PER value. Differences between black and white beans were observed and attributed to variations in structure, composition, and varieties, among other factors. Cooking complements the effect of germination by improving the protein quality of P. vulgaris and increasing its bioavailability for the human consumption.     

Breakdown of the soluble soybean antigen in the digestive tract of adult rats

Adult male Wistar rats received intragastrically a protein mixture containing 3H-labeled reserve protein of soy beans (PSB), the soy protein isolate 500-E of Ralston Purina Co (USA) being chosen as a protein source. Immunoreactive and TCA-precipitable 3H-PSB was determined in the stomach and small bowel content, 20 and 60 minutes after the administration. The experiment showed more complete inactivation of soy antigen as compared to chick ovalbumin (the authors' data), bovine serum albumin, chick ovomucoid and Kunitz trypsin inhibitor (the literature data). Basing on the results obtained, it is suggested that the soy reserve protein possesses low allergenic properties.     

Simplified Enzymatic-gravimetric Method for Total Dietary Fiber In Legumes Compared with a Modified AOAC Method

Two methods (an AOAC and a simplified enzymatic-gravimetric method) were used to analyze seven types of canned legumes and eight cooked legumes. Total dietary fiber (TDF) of the canned products ranged between 17% and 23% (dry basis) for chick peas, Great Northern beans, kidney beans, pinto beans, pork & beans, vegetarian beans in tomato sauce, and 27–31% for wax beans. These values were comparable for both methods. However, results on cooked legumes were very different between methods. TDF values for several types of beans and peas were higher and ranged between 31% and 5.5% by the AOAC/Tris-Mes buffer method as compared to 17% and 29% using the simplified method. Chemical analysis of dietary fiber residues showed the major difference between the methods was in the extent of starch removal as affected by starch gelatinization.     

EFFECT OF BROAD BEAN AND PEA PHENOLICS ON THE ACTIVITY OF LIPASE AND LIPOXYGENASE

The total content of phenolics in broad beans ranged from 276 to 794 mg/kg of sample on a dry weight basis (dwb), while in peas varied from 144 to 691 mg/kg of sample (dwb). Broad beans contained a higher level of proanthocyanidins than peas. Proanthocyanidins were the predominant phenolics in beans and peas. Phenolics were mostly located in seed coats. The methanolic extracts of phenolics from both broad beans and peas showed great inhibitory effects towards both lipase and lipoxygenase activities.     

The apparent ileal digestibility,determined with young broilers,of amino acids in near‐isogenic lines of peas (Pisum sativum L) differing in trypsin inhibitor activity

Two pairs of near‐isogenic lines of peas were developed to have high and low concentrations of seed trypsin inhibitor. HA5 and LA5 contained 8.73 ± 0.19 and 1.45 ± 0.19 trypsin inhibitor units per mg dry weight respectively, whereas HB5 and LB5 contained 7.40 ± 0.65 and 1.78 ± 0.15 trypsin inhibitor units per mg dry weight respectively. The four pea samples were included in semi‐synthetic diets and evaluated in a poultry metabolism experiment, using birds aged 3 weeks, to determine the coefficient of apparent ileal amino acid digestibility (CAID). There was a significant difference in CAID for the amino acids reported that correlated with pea genotype. Thus, for example, CAID for cystine was 0.738 ± 0.0196 and 0.812 ± 0.0128 for HA5 and LA5 respectively and 0.721 ± 0.0139 and 0.804 ± 0.0178 for HB5 and LB5 respectively. Corresponding data for methionine, the other main nutritionally deficient amino acid in peas, were 0.887 ± 0.0103, 0.930 ± 0.0089, 0.885 ± 0.0083 and 0.929 ± 0.0125 respectively. Other amino acids followed similar patterns. These data provide information on the nutritional consequences of variation in trypsin inhibitor content of pea seeds in near‐isogenic backgrounds. Plant breeding for low trypsin inhibitor activity in seeds accordingly offers potential for improving nutritional value. © 2003 Society of Chemical Industry     

Exocrine Pancreatic Secretions in Young Pigs Fed Diets Containing Faba Beans (Vicia faba) and Peas (Pisum sativum): Nitrogen,Protein and Enzyme Secretions

Two experiments were carried out to investigate the effect of feeding diets containing faba beans and peas on pancreatic secretions in young pigs fitted with a pancreatic pouch re-entrant cannula. In Experiment 1, eight barrows, with an average initial weight of 8·5 kg, were fed one of two maize starch-based diets formulated to contain 200 g crude protein (CP) kg⁻¹ according to a completely randomised design. In one of the diets, soya bean meal was the sole protein source; in the other diet, soya bean meal and faba beans (cv Fibro; dark-flowering) each supplied 50% of the dietary CP. In Experiment 2, five barrows, with an average initial weight of 18·1 kg, were fed one of two diets according to a two-period change-over design. The diets were formulated to contain 150 g CP kg⁻¹ with peas (cv Ascona or cv Radley) as the sole protein source. In both experiments, the experimental periods consisted of 8 days: 6 days adaptation followed by a 2 day collection of pancreatic juice. The soya bean meal diet and the faba bean diet contained 0.04 and 0.21% tannins (catechin equivalents), respectively. The trypsin inhibitor activities of the Ascona and Radley pea diets were 0·76 and 3·24 mg of trypsin inhibited per gram, respectively. In both experiments, diet did not affect ( P> 0·05) the pancreatic secretions of nitrogen, protein, amylase, lipase and chymotrypsin. In Experiment 1, specific trypsin activity was higher ( P< 0·05) in pancreatic juice from pigs fed the diet containing soya bean meal and faba beans (53700 units litre⁻¹) than for those fed the soya bean meal diet (41200 units litre⁻¹). However, there was no effect ( P> 0·05) when trypsin activity was expressed as total activity (units 24 h⁻¹). It is concluded that the inclu-sion of faba beans and peas in diets for young pigs has only minor effects on exocrine pancreatic secretions.     

The inhibition of digestive enzymes by extracts of field bean (Vicia faba).

Protease inhibitor activity was determined for a wide range of differing field bean (Vicia faba) varieties and genotypes. Although a two-fold variation was observed under the assay conditions used, the highest values were approximately five times less active in inhibiting trypsin than either soya or navy beans. No correlation was found between protein content and protease inhibitor activity. Water extracts from the testa from coloured-flower varieties inhibited the activity of α-amylase, lipase and trypsin. The addition of polyvinylpyrrolidone reactivated these enzymes to varying degrees. No inhibitory activity was found in similar extracts from white-flowered varieties. It was concluded that the enzyme inhibition exhibited by extracts of the seed coat of coloured varieties was due to the presence of tannins.     

Trypsin inhibitor content in some varieties of soya bean (Glycine max L.) and sunflower seeds (Helianthus annuus L.)

Some varieties of soya beans and sunflower seeds were analysed for protein, fat, moisture and trypsin inhibitory activities. The soya beans were high in protein content and all of them were equally high in trypsin inhibitory activity. Some varieties of sunflower seeds were adequate in fat and proteins, some were very low and others were reasonably free from trypsin inhibitors. Extensive cultivation of the sunflower seeds having adequate amount of fat and protein, but free from trypsin inhibitor should be encouraged.     

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%).     

Trypsin Inhibitor from 3 Legume Seeds: Fractionation and Proteolytic Inhibition Study

ABSTRACT: The trypsin inhibitor from navy beans (Phaseoulus vulgaris), red kidney beans (Phaseoulus vulgaris L.), and adzuki beans (Vigna angularis) provided by the Royal Project Foundation in Thailand was isolated by heat and ammonium sulfate (AS) precipitation. Incubation at 70 °C for 10 min produced the highest trypsin inhibitor recovery for all legumes. The AS precipitation with 60% to 80% saturation (precipitate IV) resulted in 41-, 88-, and 34-fold of the purity and (−)26%, 126%, and (−)47% of percentage of activity increase for navy beans, red kidney beans, and adzuki beans, respectively. The trypsin inhibitors had a molecular weight of 132 kDa for navy beans, 118 kDa for red kidney beans, and 13 kDa for adzuki beans under nonreducing conditions. The obtained precipitate IV fraction from each legume effectively prevented the degradation of the tilapia muscle with concentration dependent. The myosin heavy chain increased as the concentration of the inhibitor fraction increased, especially at the highest level of addition. The result indicated that the precipitate IV from these legumes have potential for use as a protease inhibitor in fishery related products.     

Nutritional Quality of Great Northern Bean Proteins Processed at Varying pH

Heating whole dry beans at pH well above or below their average protein isoelectric point of 6.3, results in significant increases in protein digestibility, as measured by the rat NPR assay. Yet the nutritional quality of these pH-adjusted beans was lower than that for conventionally cooked dry beans due to the loss of cysteine/cystine (Cys) from the beans during the long pH adjustment step as well as the increased sensitivity of Cys to heat at alkaline pHs. In contrast pH adjusted bean flour slurries, after rapidly drying (40 set) on a double drum drier, yielded products having a high protein digestibility (>80%), low trypsin inhibitor content (< 10mg TI/g protein) and showing little or no loss of Cys.     

Detection of fungal infection in five different pulses using near-infrared hyperspectral imaging

The five major pulse crops grown in Canada are: chick peas, green peas, lentils, pinto beans and kidney beans. Potential causes of fungal infection in these pulses are Aspergillus flavus and Penicillium commune. Early stages of fungal infections in pulses are not detectable with human eyes and traditional microbial methods require significant time to detect fungal infection. Near-infrared (NIR) hyperspectral imaging system is an advanced technique widely being assessed for detection of insect infestation and fungal infection in cereal grains and oilseeds. The primary objective of this study was to assess the feasibility of the NIR hyperspectral imaging system to identify fungal infections in pulses. Hyperspectral images of healthy and fungal infected chick peas, green peas, lentils, pinto beans and kidney beans were acquired and features (six statistical and 10 histogram) were used to develop classification models to identify fungal infection caused by A. flavus and P. commune. Images of healthy and fungal-infected kernels were acquired at 2 week intervals (0, 2, 4, 6, 8 and 10 weeks from artificial inoculation). Six-way (healthy vs the five different stages of infection) and two-way (healthy vs every stage of infection) models were developed and classifications were done using linear discriminant analysis (LDA) and quadratic discriminant analysis (QDA) classifiers. The LDA classifier identified both types of fungal infections with 90–94% accuracy while using the six-way model, and with 98–100% accuracy when using the two-way models for all five types of pulses. The QDA classifier also showed promising results as it gave 85–90% accuracy for the six-way model and 96–100% accuracy for the two-way models. The two fungal species could not be differentiated by the hyperspectral imaging.