Quick-cooking beans (Phaseolus vulgaris L.): II. Phytates,oligosaccharides, and antienzymes

Effects of the quick-cooking processes on phytate and oligosaccharide levels, and on trypsin and chymotrypsin inhibitors, were investigated in three bean varieties (Phaseolus vulgaris L.: Great Northern, red kidney, and pinto). Beans soaked in distilled water had lower levels of phytate-P than those soaked in a mixed salt solution. Leaching losses of oligosaccharides were nearly the same in different soaking treatments for all the beans except kidney beans. Residual trypsin inhibitor activities (TIA) in cooked quick-cooking beans were about 10% compared with about 20% for chymotrypsin inhibitor activities (CTIA) in the same bean products. -Irradiation was more effective in reducing TIA than CTIA and paralleled destruction by moist heat.Utah Agricultural Experiment Station Journal article no. 2480.     

Studies on green beans (Phaseolus vulgaris L.)

The phytoalexins produced after the inoculation of green bean pods (Phaseolus vulgaris L.) with the spore suspension of three fungi viz.Fusarium solani, Penicillium patulum andPhytophthora megasperma were studied. Five phytoalexins were isolated and identified as phaseollin, coumestrol, kievitone, phaseollidin and 6--hydroxyphaseollin. Their identity was proved according to m.p., TLC, UV and MS by comparison with authentics. Moreover, the preliminary screening of their antifungal activity was carried out.     

Water uptake during cooking of dry beans (Phaseolus vulgaris L.)

Water uptake during cooking of ten dry bean (Phaseolus vulgaris L.) varieties was investigated. Water uptake during early stages of cooking was characteristic of the variety. Although the optimal cooking times varied widely (52–85 min), all the beans absorbed similar amounts of water when cooked for their optimal times. Cooking times were significantly correlated with W_{20 min} (r=–0.92) and hardness index (r=0.76) of beans. Most other physical characteristics excepting the surface area of beans were generally unrelated to theW _{20 min},W _opt, and cooking times. No significant correlation was observed between phytate content and cooking times of beans. On cooking for their respective optimal times, all varieties absorbed nearly 1.5 times their weight of water and attained a moisture content of about 65% (wet basis).     

Antinutritional factors in anasazi and other pinto beans (Phaseolus vulgaris L.)

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

Seed characteristics and nutrient composition of selected beans (Phaseolus vulgaris L.) with different ozone tolerance

Ozone sensitivity, nutritional quality, seed characteristics, and growth habit of beans (Phaseolus vulgaris L.) were evaluated in two seperate experiments. In the first experiment the data showed a significant variation among 34 bean accessions for ozone sensitivity following acute exposure of 18-day-old plants to 0.6 µl/l O₃ for 2 hours under environmentally controlled greenhouse conditions. PI-163579, PI-169735, PI-171790, PI-176684, PI-201374, PI-310711, PI-345576, PI-370569, PI-379435, and PI-414831 were identified as tolerant to acute ozone exposures. Protein, oil, starch, sugar, and ash contents in the seed of selected germplasm were determined and no correlation was found between these components and ozone sensitivity. Seed size and growth habit varied considerably among the 34 accessions but were not correlated to ozone sensitivity. In a second experiment, ten accessions, selected from the tolerant ones identified in the first experiment, were subjected to chronic ozone exposure in open-top chambers at 0.04 and 0.08 µl/l concentrations for 7 hours/day 44 days after transplanting. Based on foliar injury and yield reductions, only PI-370569 and PI-414831 were tolerant to prolonged ozone exposure (0.08 µl/l). A significant positive correlation (r=0.83) existed between foliar injury rating from chronic treatments involving 0.04 and 0.08 µl O₃/l and acute exposure (0.6 µl O₃/1/2 hours). The data indicated that acute ozone exposure can be used to initially screen a large number of bean accessions, however, this is an imperfect indicator of ozone sensitivity with chronic exposure.Agricultural Research Station Journal Article Series, No. 191. The use of any trade name varieties and/or vendors does not imply the exclusion of other products or vendors that may also suitable.     

Research needs to up-grade the nutritional quality of common beans (Phaseolus vulgaris)

Beans are important sources of nutrients in diets based on cereal grains and starchy foods. The paper reviews briefly some of the factors of nutritional importance which are relatively well defined and which may serve as a basis for recommendations for further study and for establishing nutritional objectives for breeding.     

Influence of insecticidal plant materials used during storage on sensory attributes and instrumental hardness of dry edible beans (Phaseolus vulgaris L.)

Three plant products with known insecticidal properties, a dry extract of flowers ofChrysanthemum cinerariaefolium (Trevir.) Vis. produced in Rwanda, an ethanol extract of seeds of neem,Azadirachta indica A. Juss., and crushed leaves ofTetradenia riparia Hochst Codd., a traditional Rwandan medicine, were mixed with beans,Phaseolus vulgaris L., for storage protection. These plant-protected beans were compared with off the shelf beans that were being sold to consumers by the Rwandan National Agricultural Products Marketing Organization (OPROVIA). A trained sensory panel determined that beans treated with neem andC. cinerariaefolium were as acceptable after 8 months storage as those being sold throughout Rwanda by the marketing organization. Beans marketed by this organization were all treated with the standard insecticide application in Rwanda, 0.01% weight/weight pirimiphos methyl in a powder formulation. Instrumental hardness (% hard-to-cook/mean gram force) after 20 months of storage was acceptable for beans stored with neem or withC. cinerariaefolium or with the conventional government application of pirimiphos methyl. Use of either neem orC. cinerariaefolium for storage protection should not affect consumer acceptance of dry beans.     

Phytic acid in stored common bean seeds (Phaseolus vulgaris L.)

Four varieties of common bean seeds stored at 4°C, 80% relative humidity, for one to eight years showed no differences in proximal chemical composition, Seeds 5–6 years old absorbed more water than 1 to 4 year-old seeds. The cooking time required for five year-old seeds was 6 hours, while the fresh seeds needed 3/4-to-one hour cooking time. The most remarkable difference was in phytic acid content, which decreased 94% to 98% during long storage.     

The analysis of development of hardbean during storage of black beans (Phaseolus vulgaris L)

The course of development of hardbeans ofPhaseolus vulgaris was followed during storage. After 40 days seed viability dropped rapidly and after 50 days leakage of solids which had remained constant up till then increased rapidly. Increased metabolic activity led to phytin hydrolysis and membrane deterioration leading to leakage of Ca and Mg and thence to pectin desolubilisation and textural deterioration, i.e. hardbeans.     

Unavailable carbohydrates in common bean cotyledon (Phaseolus vulgaris L.) Canario group

Unavailable carbohydrates in cotyledon flour were quantified from four varieties of common bean (Phaseolus vulgaris L) belonging to the Canario group. The pectin content, as percentage of anhydrogalacturonic acid, ranged between 1.57% and 2.3%. Percentages of hemicellulose A and B were similar, with average values of 2.81% and 2.61%, respectively. The polysaccharide extracted with 10% trichloroacetic acid was determined; its yield was 3.17%. This value dropped to 2.35% when the cotyledon flour was previously hydrolyzed with polygalacturonase. The average value of cellulose was 1.36%.     

Quality attributes of three new improved lines of Nigerian lima beans (Phaseolus lunatus L. Walp.)

Three promising new improved lines of lima beans (Tpl 1^B, Tpl 7^A and Tpl 175^A) were evaluated for physicochemical properties and cooking quality. The beans varied in seed dimensions and weights with Tpl 1^B and Tpl 7^A having smaller seed volume than Tpl 175^A. Seed coat percentages, leached solids and swelling capacities were within a range of 10.2–19.6% (w/w), 0.44–0.92 g/100 g and 94.0–121.0 g/100 g dry bean, respectively. Cooking times varied between 62 and 81 min without soaking and were reduced by about 34%following a presoaking treatment in water for 12 h at room temperature (28 ± 1 °C). Small seeds absorbed higher amounts of water during soaking and required more cooking time than larger seeds. No significant (p>0.05) difference in cooked texture was found between unsoaked beans cooked for 50 min and soaked beans cooked for 30 min,suggesting that cooking times and cooked texture for all lines were improved through soaking.     

Single Varietal Dry Bean (Phaseolus vulgaris L.) Pastas: Nutritional Profile and Consumer Acceptability

Plant Foods for Human Nutrition - Dry beans (Phaseolus vulgaris L.) are a nutrient dense food rich in protein, dietary fiber, minerals, and folate. Consumption of dry beans is relatively low in the...     

Preparation and antinutritional characteristics of dry bean (Phaseolus vulgaris L.) protein concentrates

Protein concentrates and starches were prepared by a wet extraction process from five dry bean (Phaseolus vulgaris L.) cultivars. The protein contents ranged from 69.7–76.4%. Concentrates prepared from dehulled beans under similar conditions had higher protein contents (80.6–87.9%). Each additional washing of the concentrates with distilled water increased their protein content. However, the protein recovery progressively decreased. The yield of starch ranged from 48.0–51.1% of the starting material. The solubility of bean proteins was minimal at pH 4.0, and under alkaline conditions, it was influenced by the tannin contents of the concentrates. Protein concentrates had lower trypsin, chymotrypsin, and amylase inhibitory activities as well as lower phytic acid and tannin contents compared to whole bean flours.     

The effect of slow-cooking on the trypsin inhibitor and hemagglutinating activities and in vitro digestibility of brown beans (Phaseolus vulgaris,var.Stella) and kidney beans (Phaseolus vulgaris,var.Montcalm)

Brown beans and kidney beans were subjected to two modes of cooking in a household slow cooker: (A), a fixed low setting for 10 h, and (B), a high setting for 2.5 h and a low setting for 7.5 h. Temperature changes in the beans were recorded. With treatment A over 90% of the hemagglutinating and trypsin inhibitor activities occurred after 6 h at which time the temperature had reached 80°C. With treatment B inactivation of these activities was almost complete at the end of 2 h when a maximum temperature of 100°C had been attained. The in vitro digestibility of the bean protein was considerably increased by either treatment. By way of contrast, only 20 min of heating was required to destroy these activities when the beans were brought to a boil in an open vessel.     

Differences in development of common bean (Phaseolus vulgaris L.) crops and pod fractions within a crop: I. Seed growth and maturity

Two experiments with common bean cultivars Rosecoco and Mwezi Moja aimed at increasing insight into differences in development with time of seeds from pods of different earliness classes within a crop. Pods were divided into three earliness classes (early, medium, and late) in relation to the fourth class, the overall crop. In all pod classes, cultivars and seasons, seeds achieved physiological maturity (PM: maximum dry weight) when fresh weight was at its maximum. PM was achieved at 58% seed moisture content in seeds from all pod classes and cultivars. Seeds from earlier pods tended to reach PM earlier than those from other classes. The time when seeds developed their final red purple colour pattern was a reasonable indicator of PM, though not completely accurate. Harvest maturity (HM: 20% seed moisture content) was reached earlier in earlier pods in cv. Rosecoco, but the timing was the same for all pod classes in cv. Mwezi Moja. The period for seeds to dry down from 58 to 20% moisture content was longer in seeds from earlier pods in cv. Mwezi Moja, but not in cv. Rosecoco. The course of decline in moisture content between 58 and 20% differed between pod earliness classes, but was not systematically affected by earliness. The timing of seed development in the overall crop could be explained by the timing of seed development in pods of different earliness classes. Relationships among seed moisture content and seed or pod colour in whole crops differed from those in pods of individual earliness classes.     

Variation in parameters related to leaf thickness in common bean (Phaseolus vulgaris L.)

Greater leaf thickness is usually associated with greater leaf carbon assimilation rate, but the tradeoff between thicker versus larger leaves also affects canopy structure and light interception. Many studies equate the ratio of dry leaf mass to area (leaf specific mass) with leaf thickness. This approximation has utility but ignores differences in true thickness due to variation in water or air content and other factors. To understand better variation in leaf thickness in common bean (Phaseolus vulgaris L.), 14 parameters related to thickness were compared for a diverse set of bean cultivars grown in three field environments in Colombia. The parameters included leaf thickness per se as measured anatomically or with a micrometer, leaf specific mass expressed on dry and fresh weight bases, leaf optical density measured at 670 nm, total leaf chlorophyll concentration expressed on a leaf area basis, leaf tissue density, and nitrogen concentration expressed on fresh and dry weight bases. Relative contributions of air, water, and dry matter to leaf thickness were also estimated. Most parameters showed large differences among lines, consistent with previous reports that cultivars from the Mesoamerican genepool have thicker leaves than those of the Andean genepool. Parameters varied greatly with environment and sampling date. The results support the need to control for leaf water content when studying leaf thickness. Furthermore, including mid and lateral rib tissue in leaf samples appeared to bias data sufficiently enough to double estimates of leaf thickness and specific mass. Based on time required for measurement and ability to detect cultivar differences, measuring leaf thickness with a micrometer and leaf optical density appeared the most promising for rapid characterization of leaf thickness.     

Interrelationships between certain physical and chemical properties of dry bean (Phaseolus vulgaris L.)

The interrelationships among certain physical and chemical properties of ten cultivars of dry beans (Phaseolus vulgaris L.) were investigated. The length/breadth ratio was similar (1.51–1.65) except for kidney beans (>2.0) and sanilac (1.37) cultivars. The breadth/thickness ratio ranged from 1.17–1.65. The 100-bean weight indicated a wide variation of 15.03–50.33 g. The density, bulk density, and porosity characteristics were within a narrow range of 1.18–1.36 g/cc, 68–75 g/100 cc, and 40.7–48.5%, respectively. Water uptake rates during the first 6 h of soaking at room temperature (21 °C) were characteristic of the cultivar. At the end of 24-h soaking, however, all cultivars had absorbed similar amounts of water (approximately 1 g/g bean). Leaching losses (g solids leached/100 g beans) had characteristic trends and ranged from 0.54 for cranberry to 3.46 for sanilac cultivars after 24-h soaking. Most correlations between selected chemical constituents and physical characteristics of the dry bean were relatively low.Journal Paper No. 2751 of Utah Agricultural Experiment Station and a contribution of Western Regional Project W-150.     

Physical Properties of Extruded Products from Three Mexican Common Beans (Phaseolus vulgaris L.) Cultivars

The physical properties of extruded products from three Mexican common bean cultivars were investigated. Common bean cultivars Flor de Mayo, Pinto Villa and Bayo Victoria from the same harvesting season (2006) were used in this work. Beans were milled and the flour was hydrated to 24, 26 and 28 g of water/100 g of dry weight. Two temperatures, 130 degrees C and 165 degrees C at the end of the extruder barrel without die, were experimented. Common bean flour extrudates were evaluated for water absorption index (WAI), water absorption capacity (WAC), oil absorption capacity (OAC), and emulsifying capacity (EC). Flor de Mayo extrudates showed the highest WAC and WAI values. Thus starch from Flor de Mayo beans showed minor restricted water availability. In all cases, the OAC of extruded products was lower than the crude bean flour. The EC for Bayo Victoria flour increased as a consequence of the extrusion process. The EC for Flor de Mayo was higher at lower temperature and lower moisture content than Pinto Villa and Bayo Victoria beans. EC behavior of Pinto Villa was similar to Bayo cultivar. These results indicate that it is possible to produce new extruded products with good physical properties from these common bean cultivars.     

The degradation of lectins,phaseolin and trypsin inhibitors during germination of white kidney beans,Phaseolus vulgaris L.

White kidney beans (Phaseolus vulgaris), cv Processor, contain a relatively high content of phaseolin (storage protein), lectins and a special group of glycoproteins as well as a considerable amount of protein-type trypsin inhibitors. Protein digestion of raw Processor beans in monogastrics, for example pigs, is disturbed by poorly digested, phaseolin lectins, which can bind to carbohydrates in brush border membranes of the small intestinal epithelium, and trypsin inhibitors. The effect of the germination of white kidney beans on lectins, phaseolin and trypsin inhibitors was studied in order to achieve a degradation of lectins, phaseolin and trypsin inhibitors and an increase ofin vitro enzymatic hydrolysis of the protein of bean flour. Therefore, whole bean extracts were examined throughout a germination period of up to seven days for their lectin and phaseolin pattern, lectin content, binding capacities of functional lectins towards brush border membranes and trypsin inhibitor content. In addition thein vitro enzymatic hydrolysis by pepsin and pancreatin of the protein from flours of (un)germinated white kidney beans was studied. SDS-PAGE demonstrated a degradation of E-lectins and a disappearance of L-lectins and phaseolin during germination. Results indicated a decrease of the lectin content by 85%, a loss of binding capacities of functional lectins towards brush border membranes by 91%, and a decrease of trypsin inhibitors by 76%, in bean flour after germination for seven days. A maximum inin vitro enzymatic hydrolysis of protein from bean flour was already established after germination for half a day.     

Comparative study of the chemical composition of wild and cultivated beans (Phaseolus vulgaris)

Five wildPhaseolus vulgaris beans were compared with five cultivatedPhaseolus vulgaris beans in proximate composition, total (true) protein, amino acid composition, and toxic and antinutritional factors. The wild beans contained more protein (25.5% vs. 21.7%), ash (5.15 vs. 4.15%), crude fiber (7.08% vs. 5.04%) compared to cultivated beans while the former contained less fat (0.56 vs. 0.89%) and carbohydrates (61.64 vs. 68.05%). Sulfur amino acids were found to be limiting in both groups of bean as expected; however, the cultivated beans had a higher content of the limiting amino acids. Therefore, the cultivated beans showed a better amino acid profile than the wild beans. Toxic factors were not found in either type of bean; the determinations included saponins, alkaloids, and cyanogenic glycosides. The antinutritional factors investigated were hemagglutinins (lectins) and trypsin inhibitors. The wild beans presented a higher content of trypsin inhibitors (28 TUI per mg) and lectins (9.6) than the cultivated beans did (21 TUI per mg and 7 respectively). From the chemical point of view, domestication seems to be positive; however, the better protein nutritive quality of the cultivated beans should be further confirmed by biological assays.