M. A. Uebersax

Dry Beans and Pulses Production, Processing and Nutrition

The common beans and pulses are diverse food resources of high nutritional value (protein, energy, fiber and vitamins and minerals) with broad social acceptance. These legume crops demonstrate global adaptability, genotypic and phenotypic diversity, and multiple means of preparation and dietary use. Beans and pulses are produced in regions as diverse as Latin America, Africa, Asia, and North America, and on a scale similar to some other crops, such as wheat, corn, rice and soybeans.

Production and characterization of a protein concentrate from navy beans (Phaseolus vulgaris)

Abstract Different methods were evaluated for the production of a navy bean protein concentrate (NPC). Most of the concentrates prepared by isoelectric precipitation contained 80–83% protein. Salt fractionation of the navy bean flour resulted in low concentrate yields. The most satisfactory method for production of a NPC from dry bean flour was a modification of the isoelectric precipitation method of Fan & Sosulski (1974) in which the centrifugation speed was increased to 15 000 × g. This concentrate had a protein content of 83·9% and a starch content of 2·4%. The concentrate contained more soluble protein and less phytohemagglutinin than the flour from which it was produced. The major protein was a 7S protein with three subunits of about 45–48 k Da typical of vicilin. About 10% of the protein present was in the form of a 60 kDa fraction.

Production and functional characteristics of protein concentrates.

Protein concentrates derived from common dry beans (Phaseolus vulgaris L.) may improve world protein resources, reduce on-site preparation time and expense and provide improved nutrition. Several different methods have been studied for the production of these concentrates, including alkali extraction and isoelectric precipitation, ultrafiltration, air-classification and salt extraction under high salt concentrations. Recent studies using solid-solid dry roasting, pin milling and air-classification resulted in the following percent mass fractions: hull/fiber (10%), coarse/starch (70%) and fine/protein (20%). Results indicated that the protein fractions were approximately 45–50% protein, low in raffinose and stachyose and hadtrypsin inhibitor activity reduced to about half of that of raw beans. Nitrogen Solubility Index (NSI) ranged from 33–70% and was associated with the thermal conditions applied during dry roasting. The flours had a bland flavor without the bitter off-flavors which have traditionally limited the use of dry beans in formulated foods. Most minerals and phytic acid tended to be associated with protein flour; however, although iron may have been bound to phytic acid, its absorption by anemic rats was not hindered by the presence of endogenous phytic acid. These flours produced acceptable products when incorporated into cookies, doughnust, quick breads and leavened doughs.

Characteristics and utilization of dry roasted air-classified navy bean protein fraction

Navy beans,Phaseolus vulgaris, were dry roasted in a particle-to-particle heat exchanger, dehulled by air aspiration, pin-milled and air-classified to yield a high protein fraction. Proximate analyses, nitrogen solubility indices and oligosaccharide contents of this high protein fraction as influenced by processing parameters which affected final product temperature were determined. Farinograms of wheat/bean protein fraction composite flours were run. A high-protein bean flour fraction was selected from these dry and roasted treatments and used in product development. Quality characteristics and consumer acceptability of high-protein prototype products were evaluated. Results of this research indicate that the dry roasting process influences the characteristics of the air-classified protein fraction. Flour color, nitrogen solubility and dough mixing properties were most greatly influenced by roasting time and temperature. Increased roasting resulted in increased browning and decreased nitrogen solubility and dough mixing stability. Wheat flour bread products, substituted with low levels of high-protein bean flour, were of high quality.

A statistical evaluation of three methods for measuring lipid oxidation in a model system

Abstract The extent of oxidation in purified linoleic acid as a simple lipid model system was measured by total carbonyls (TC), peroxide values (PV) and thiobarbituric acid (TBA) values. Regression equations established relationships between individual methods and between each method and time, temperature and air flow rate independently. Correlation coefficients were statistically significant (P

Thiamin content in air-classified Phaseolus vulgaris (Pinto Bean) flour fractions

Abstract Dry roasted whole, hull, and air-classified Phaseolus vulgaris (pinto bean) flour fractions were analyzed for thiamin content using a fluorometric procedure. On a 100 g dry weight basis, the mean thiamin values of each pinto bean flour fraction were whole bean, 0.80 mg; hull, 0.65 mg; intermediate starch, 1.1 mg; intermediate protein, 1.08 mg; high starch, 0.87 mg; and high protein, 0.83 mg. Significant differences between thiamin levels of the legume fractions were found with the following exceptions: whole bean vs hull, high starch and protein fractions; intermediate starch vs intermediate protein fractions; and high starch vs high protein fractions. Significant differences among the flours reveal that thiamin composition is not always equally distributed among the fractions and that partitioning among some fractions does occur.