Seed anatomy and culinary properties of some Tanzanian french beans (phaseolus vulgaris L.)nd culinary properties of some Tanzanian french beans (phaseolus vulgaris L.)

Dry beans from Dar es Salaam markets and food shops have been studied to determine factors affecting their cooking quality. Uniform cooking procedures with distilled water was done to determine the differences in their cooking quality. Morphometrics of the plants grown from the seeds cannot be used to give a clue to the cooking qualities of the cultivars. Other factors studied were: seed viability, seed water uptake, the intrinsic seed moisture contents, age of the seeds, influence of rations including calcium, sodium and potassium, pectin contents, phytin-phosphorus content, effect of chemical solutions and the structure of the seed coat. The chemical solutions used as cooking media were sodium chloride, calcium chloride, sodium bicarbonate and ammonium carbonate of different concentrations. Seed viability was found to have no bearing on the cookability of beans. Seed water up take and intrinsic seed moisture content have not shown direct influence on the cooking quality of French beans. Freshly harvested beans were observed to soften easily on cooking. Of the three captions studied, calcium, sodium and potassium, the former was represented most while the latter were represented least in the bean leachates of the 10 cultivara. Determination of calcium content in the testa and cotyledons separately through ashing revealed more calcium content in the testa than in the cotyledons.The intrinsic pectin content and phytin-phospherus content were found to correlate positively and significantly to the cookability of beans. Solutions of ammonium bicarbonate as the cooking media softens the seed coats and cotyledons of beans. Ammonium carbonate solution being the most efficient in this respect.Solutions of calcium chloride in concentrations of 0.02M depresses cookability of beans. Natural calcium impurities were observed to occur in tap water (about 1.10mg/1) and in crude common salt (about 3.5mg/g).These impurities seem to have meaningful negative influence on cookability of beans. Seed anatomy mainly that of the testa was assessed.Outicle thickness seen to have no significant effect on the cookability of beans. The testa thickness and overligni-fication of the palisade and spongy cell walls contribute negatively and significantly to the cookability of beans.