Oligosaccharides in raw and processed legumes

 Oligosaccharides from several types of raw and processed legume seeds consumed in Spain, e.g. lentils (Lens culinaris L.), chickpeas (Cicer arietinum L.), red kidney beans (Phaseolus vulgaris L.), white common beans (Phaseolus vulgaris L.), “Judiones de la Granja” great white beans (Phaseolus vulgaris L.) and faba beans (Vicia faba L.), were analysed by high performance liquid chromatography. The total sugar content ranged from 6.69% to 9.99%, and oligosaccharides represented 25–46% of the total sugar, in the various dry legumes. The main oligosaccharide in raw faba beans was verbascose (3.32%), and stachyose in the remaining legumes (2.21–3.23%). Different amounts of sucrose and traces of glucose, fructose and small amounts of inulin were present in raw samples of all the legumes. After soaking in tap water the loss of oligosaccharides was lowest in red beans (1.25%) and highest in common white beans (27.6%). Pressure cooking, without previous soaking, resulted in no oligosaccharide loss in common white beans but a loss of up to 32% in chickpeas. After pressure cooking of soaked legumes, the loss of stachyose ranged from 14.2% in red beans up to 35.9% for lentils. Substantial amounts of flatus-producing factors can be eliminated by common processing methods. Received: 12 May 1997 / Revised version: 17 July 1997     

Saponin content of food plants and some prepared foods

Quantitative thin layer chromatography was used to estimate the saponin content of 20 common food plants and also of foods prepared from some of them. The food plants found to be richest in saponins were chickpeas (Cicer arietinum), soya beans (Glycine max), lucerne (alfalfa) sprouts (Medicago sativa) and varieties of Phaseolus vulgaris (navy beans, haricot beans, kidney beans). Saponins were not destroyed by processing or cooking. They were present in falafels (prepared from chickpeas), canned baked beans, canned broad beans and protein isolate from faba beans. However, the saponin content of a fermented soya bean product (tempe) was only half that of whole soya beans. Guar meal (Cyamopsis tetragonolobus) contains saponins but only a trace could be detected in samples of guar gum.     

Low molecular weight carbohydrates from leguminous seeds; a new disaccharide: Galactopinitol

Twelve mature leguminous seed crops were extracted with 70% ethanol, and their low molecular weight carbohydrates estimated by gas chromatography. Pinitol (3-O-methyl-D-chiro-inositol) and three isomers of a new disaccharide, α-D-galactopyranosyl-pinitol, for which the name galactopinitol is proposed, were isolated from soya beans (Glycine max). Pinitol and galactopinitol were also identified in chick peas (Cicer arietinum L.), lentils (Lens esculenta) and beans (Phaseolus vulgaris L.). Their amounts ranged from 0.2 to 0.9% and 0.03 to 0.8% of dry weight respectively. The possible role of galactopinitol in biosynthesis of the sugars of the raffinose family and in flatulence is discussed.     

Comparative studies on the antioxidant activities of nine common food legumes against copper-induced human low-density lipoprotein oxidation in vitro

ABSTRACT:  Epidemiological studies demonstrated that the consumption of dietary antioxidant was associated with the prevention of atherosclerosis. The aim of this study was to investigate the antioxidant activities of the hydrophilic extracts from 9 selected legumes based on copper-induced human LDL oxidation model in vitro . The antioxidant activities were assessed on the basis of the formation of conjugated dienes (lag time of oxidation) and thiobarbituric acid reactive substances (TBARS) as the early and later stage markers of LDL oxidation. The results showed that the extracts of black beans ( Phaseolus vulgaris L.), lentils ( Lens culinaris ), black soybeans ( Glycine max ), and red kidney beans ( Phaseolus vulgaris L.) had significant ( P < 0.05) longer LDL oxidation lag times (128.8, 124.2, 107.7, and 111.1 min, respectively) than the LDL control group (94.9 min). No significant lag-time lengthening was observed in other tested legume extracts. On the other hand, black beans, lentils, black soybeans, red kidney beans, and pinto beans exhibited higher antioxidant capacities (Trolox equivalents) than yellow peas, green peas, chickpea, and yellow soybeans in both LDL-conjugated dienes assay and LDL-TBARS assay. Meanwhile, the antioxidant activities of these legumes against LDL-lipid peroxidation in the above assays were found to correlate very significantly ( P < 0.01) with their phenolic substances, and DPPH radical scavenging activity and ORAC (oxygen radical absorbance capacity). These results suggest that consuming black beans, lentils, black soybeans, and red kidney beans may have potential in preventing the development of atherosclerosis from the perspective of inhibiting LDL oxidation.     

Isolation and Partial Characterization of Starches from Dry Beans (Phaseolus vulgaris) and Chickpeas (Cicer arietinum), Grown in Sonora,Mexico

For a better understanding of the carbohydrate components of Mexican dry legumes, in an attempt to suggest alternative processing, starches from dry beans (Phaseolus vulgaris var. pinto) and chickpeas (Cicer arietinum var. surutato) were isolated through sedimentation procedure. They were further characterized in their: physical characteristics of shape and size by light and Scanning Electron Microscopy (SEM); chemical characteristics by proximate analyses and amylose contents; functional characteristics of gelatinization temperature, viscosity and thermal properties by Differential Scanning Calorimetry (DSC); and nutritional characteristics, % digestibility. Starch in these two legumes was firstly isolated at over 85% recovery, with an amylose content of 52.4% and 46.5% for dry beans and chickpeas, respectively. SEM and light microscopy showed starch granules with a predominantly oval shape and size in the range of 20–25μ, for both legumes. Higher gelatinization temperatures were found for dry beans than for chickpeas. Similarly, fusion enthalpies and maximum gelatinization temperature were also higher for beans, as shown by DSC. However, chickpea starch gave a slightly higher % digestibility than bean starch. These results suggested that the difference in the amylose content, in both legumes, determine the starch granule structure, their intermolecular organization and their physical and functional characteristics.     

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%).     

Nutritional evaluation and bioactive microconstituents (phytosterols,tocopherols, polyphenols,triterpenic acids) in cooked dry legumes usually consumed in the Mediterranean countries

In the present study we report the crude composition and several bioactive microconstituents content in cooked dry legumes, usually consumed in Mediterranean countries. The legumes studied were broad beans, chickpeas, two split peas varieties, two lentils varieties, pinto beans, black-eyed beans, five white beans varieties and white lupines.     

Fourier Transform Near-Infrared Spectroscopy to Predict the Gross Energy Content of Food Grade Legumes

The feasibility of Fourier transform near-infrared reflectance spectroscopy (FT-NIRS) for determining gross energy content in different food legumes has been investigated. Eighty food-grade legume samples were obtained from different retailers and local markets in Hungary and they included 42 common beans (Phaseolus vulgaris L.), 20 peas (Pisum sativum L.), 10 lentils (Lens culinaris L.), and 8 soya beans (Glycine max L.) both as full fat food and defatted. The samples were analyzed by an adiabatic bomb calorimeter and then scanned in a Bruker MPA FT-NIR Analyzer (800–2,500 nm). Two algorithms for spectral selection of calibration and validation samples, which represent variability encountered in the full population, were tested. Partial least squares regression were developed for the prediction of gross energy using four different spectral preprocessing methods (first and second derivative alone and combined with standard normal variation and multiplicative scatter correction). The results show that first derivative produced the most accurate results with very high coefficient of determinations in validation (<93 %) and with very low standard errors of validation (<0.025 kcal/g) as compared to the standard error of the reference method (0.204 kcal/g).     

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.     

Effect of Soaking and Cooking on the Oligosaccharide Content of Dry Beans (Phaseolus vulgaris, L.)

The effect of cooking conditions commonly used in Brazilian homes was determined by measuring the oligosaccharide content (sucrose, raffinose and stachyose) of beans (Phaseolus vulgaris, L.) by thin-layer chromatography. Soaking in water caused a small decrease in the oligosaccharide content of the beans and the relative amount removed was not proportional to the solubility of the sugars in water. Cooking of the whole seeds led to a larger decrease in oligosaccharide content, especially when large amounts of water were used.     

Oxalate content of some leafy vegetables and dry legumes consumed widely in Egypt

Oxalic acid and total oxalate contents were determined in four leafy vegetables and six dry legumes consumed widely in Egypt. The four vegetables, normally eaten raw, can be arranged according to their oxalate content, in descending order, as follows: green onion (leaves), green onion (bulbs), leek, radish (leaves), radish (roots) and roquette. Oxalic acid represented 76–86% of the total oxalates.Dry faba beans had the highest oxalic acid content, followed, in descending order, by fenugreek, lentils, peas, chickpeas and lupin. The ratio of oxalic acid to total oxalates differs according to the total oxalate content of the legume variety. Decortication, steeping, sprouting, stewing, boiling and baking reduced the oxalate content of seeds in different ways. Sprouting and steeping, followed by decortication, resulted in the most pronounced decrease in oxalates, especially in faba beans and lupin.     

Effects of legume processing on calcium,iron and zinc contents and dialysabilities

Legumes are a good source of calcium, iron and zinc, but are also a source of phytates and dietary fibre components that can negatively affect the bioavailability of these minerals. To estimate the latter, an in vitro dialysis method can be applied that gives the dialysability of a mineral as an estimate of its availability for absorption. Calcium, iron and zinc contents and dialysabilities in three legumes (beans, chickpeas and lentils) and the effects of cooking treatments and industrial processing on these parameters were studied. Beans had the highest calcium content (1.54 g kg^?1 dry matter (DM)) and chickpeas the lowest iron content (46.9 mg kg^?1 DM), whilst the zinc contents were similar in all three raw legumes (33.7–36.9 mg kg^?1 DM). Traditional and microwave cooking reduced the mineral contents by 9.7–36.4% for calcium, 14.2–31% for iron and 11.1–28.9% for zinc. The dialysabilities of calcium with respect to the values for the raw products were also reduced by these cooking techniques. Industrially processed legumes had higher dialysabilities of calcium, iron and zinc than traditionally or microwave cooked legumes. © 2001 Society of Chemical Industry     

Faba bean as a novel brewing adjunct: Consumer evaluation

The starch in the grains of legumes, such as faba bean (Vicia faba L.), offers an environmentally sustainable raw material for the brewing industry as their entire nitrogen fertiliser requirement can be provided by the natural process of biological nitrogen fixation. Faba bean is, therefore, distinguished from species such as spring barley (Hordeum vulgare L.), which require large amounts of synthetic nitrogen fertiliser. Consumer analysis of beer produced with faba bean as an adjunct compared with barley malt beers has not previously been assessed. This study evaluated the potential of beers brewed using 30% (w/w) dehulled bean (kernel) flour as an adjunct to malted barley, using a series of quantitative sensory tests. The first, a blind acceptance test with inferred preference, found no statistically significant difference in the taste score of the bean kernel flour adjunct beer when compared with conventional beer. In the second acceptance test, the knowledge that the beer was produced using beans did not affect the overall consumer impression of the beer, regardless of how this information was presented. These results suggest that the use of faba beans in brewing does not impact negatively on the taste or acceptability of the resultant beer. © 2019 The Institute of Brewing & Distilling     

Resistant starch and potential glycaemic index of raw and cooked legumes (lentils, chickpeas and beans)

 The amount of resistant starch (RS) in raw and processed legumes, lentils, chickpeas and beans was analysed. In addition, the effect of cooking on the availability of legume starches to enzymes, which may influence the glycaemic response, was studied. Raw legumes were found to have higher RS values (16–21%) than retrograded or cooked ones (4–8%). Cooling increased RS yields, whereas reheating maintained or decreased the value depending on the sample. On the other hand, the kinetics of starch hydrolysis revealed that the rate of digestion was higher for cooked seeds and retrograded flours (15–21% of total starch digested) than for raw flours (5–8% of total starch digested). The estimated glycaemic indices (GIs), i.e. GI₁ from the Hydrolysis Index (HI) and GI₂ from the percentage of hydrolysis within 90 min (H ₉₀), were well correlated with the reported GI values (r = 0.96 and r = 0.95 respectively, P≤ 0.05). Received: 22 September 1997 / Revised version: 24 November 1997     

Influence of germination on the nutritional quality of Phaseolus vulgaris and Cajanus cajan

Germination is a method that can modify the presence of nutrients and antinutrients in legume seeds. In this study, the changes in trypsin inhibitors activity (TIA), phytic acid, tannins, ascorbic acid, thiamine, protein digestibility and minerals in germinated black beans (Phaseolus vulgaris L.), white beans (Phaseolus vulgaris L.) and pigeon beans (Cajanus cajan L. Millsp) were evaluated. The ungerminated grains were analysed as control. A significant decrease in the content of TIA of pigeon beans (19.2%), white beans (52.5%) and black beans (25%) was observed. The reduction of phytic acid was more than 40% for the three grains germinated; for the tannins, the reduction was of 14.3% for pigeon beans, 19% for black beans and 36.2% for white beans. Germination increased the protein digestibility in a 2-4% range, and also increased the ascorbic acid by 300% for white beans, by 33% for black beans and by 208% for pigeon beans. The thiamine content increased more than 26.7%. Germination affected the mineral content erratically, depending more on the grain and the type of mineral. These variations in the content of nutrients and antinutrients of the germinated grains are attributed to the joint effect of the germination and previous soaking the grains were subjected to.     

Identification of Food and Feed Legumes by RAPD-PCR

Sixty-two legume seed samples representing 25 species were selected to investigate the identification of food and feed legumes by random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). Template DNA was extracted from defatted seed meal with SDS-containing buffer and purified by extraction with chloroform:isoamyl alcohol (24:1, v/v). Amplification was performed with Taq DNA polymerase and six commercially available 10-mer nucleotide primers using standard template dilutions for 12 species and optimum template concentrations ascertained by testing serial dilutions for the remaining species. Identification of 19 legume species, common beans (Phaseolus vulgaris), runner beans (P. coccineus), lima beans (P. lunatus), soybeans (Glycine max), broadbeans (Vicia faba), green gram (Vigna radiata), black gram (V. mungo), moth beans (V. aconitifolia), peas (Pisum sativum), chickpeas (Cicer arietinum), pigeon peas (Cajanus cajan), grasspeas (Lathyrus sativus), broad-leaved peas (L. latifolius), lentils (Lens culinaris), blue lupin (Lupinus angustifolius), European yellow lupin (L. luteus), white lupin (L. albus), alfalfa (Medicago sativa), and common sainfoin (Onobrychis viciifolia), was achieved using four of the primers. The technique may also be suitable to identify the remaining species studied, jackbeans (Canavalia ensiformis), swordbeans (C. gladiata), horsegram (Macrotyloma uniflorum), Florida velvetbean (Mucuna deeringiana), sweet trefoil (Trigonella coerulea), and birdsfoot trefoil (Lotus corniculatus).     

Non-isoflavone phytoestrogenic compound contents of various legumes

Widely consumed legumes including chickpeas, red kidney beans, haricot beans, yellow lentils, red lentils and green lentils were analysed to determine the content of non-isoflavone phytoestrogenic compounds such as quercetin, rutin, apigenin, coumestrol and lignan (matairesinol and secoisolariciresinol). Methanolic extracts obtained by ultrasound-assisted extraction were analysed by the triple quadrupole LC–MS/MS. Red kidney beans were the best source of quercetin (603.2 ± 307.2 μg/kg) and rutin (73.4 ± 14.0 μg/kg). Apigenin and secoisolariciresinol contents were the highest in yellow lentils (18.5 ± 0.84 μg/kg) and haricot beans (451.9 ± 192.2 μg/kg), respectively. Coumestrol contents of haricot beans (18.5 ± 1.45 μg/kg) and red kidney beans (18.5 ± 1.26 μg/kg) were equal to each other, and these were determined as the highest coumestrol content values. The best sources of matairesinol occurred in green lentils (28.2 ± 0.18 μg/kg) and chickpeas (27.7 ± 1.83 μg/kg). Differences between contents of each sample of the same legume were significant and remarkable, especially for quercetin and secoisolariciresinol.     

A comparison of the protein nutritive value and composition of four cultivars of faba beans (vicia faba l.) grown and harvested under controlled conditions

Faba beans (Vicia faba L.) of four cultivars, one of which was harvested in batches during the 2 months prior to normal harvesting time, and for comparison, a sample of kidney beans (Phaseolus vulgaris L.) had similar amino acid compositions with sulphur amino acids limiting in all samples. Chemical scores ranged from 45–52 and all the faba beans, when fed to rats, gave biological values in close agreement with the chemical score. Diets containing two of the cultivars were supplemented with 0.1% methionine and in both instances an increase in biological value of 22 units was obtained. Kidney beans fed to rats at the same level of crude protein resulted in the death of animals in 7–9 days. The haemaggfulinin content of the faba bean samples was 8–16 times lower than in kidney beans. Early harvesting did not affect the nutritive value of the faba beans and no differences were observed between the different cultivars, none of which showed any evidence of toxicity.     

Determination of cooking times of pulses using an automated Mattson cooker apparatus

A Mattson bean cooker apparatus was modified to electronically register individual cooked seeds by automatically recording the time taken for each plunger to drop. Contact switches, interfaced with a computer via a digital input/output board, were activated when individual plungers dropped through the cooked seeds. It was found that at the time when 80% of the seeds had been penetrated the Mattson cooker method agreed with a tactile method for determining cooking times for yellow peas (Pisum sativum), lentils (Lens culinaris), chickpeas (Cicer arietinum) and navy beans (Phaseolus vulgaris). Compared with the tactile method, the automated Mattson cooker method was more objective, much easier to carry out and more resource‐efficient. The automated Mattson cooker could provide plant breeders and the pulse industry with a reference testing method for evaluating the cookability of pulses. Copyright © 2005 Society of Chemical Industry