Legume seeds, or
pulses, are primarily composed of
carbohydrates (
starch,
sugars, and
fiber),
proteins (
albumins and
globulins), and water. The carbohydrates occur in higher concentrations than the proteins; the carbohydrates in legumes consist mostly of the
polysaccharides amylose and
amylopectin. Although composition varies, dried chickpeas at
room temperature typically contain, by weight, 19% protein, 61% carbohydrate, 6% lipids, and 14% water. These amounts are approximate, and can vary by
variety. Once the legumes are cooked and filtered from the liquid, the filtered cooking liquid is referred to as "aquafaba". Comparing the final composition of cooked beans with raw ones shows that, under 'normal" cooking conditions, approximately 5% of the initial composition of the bean has been dissolved into the cooking water. In 2018 the dry residue of aquafaba was found to consist mainly of carbohydrates (sugars,
soluble fibre) and proteins. The ratio of carbohydrate to protein in aquafaba is approximately the same ratio as is found in the uncooked dry beans. Fat and
starch, both present in the uncooked dry beans, were not detected. A concentration of 5%
dry weight to water is typical for aquafaba, although the concentration can also be increased by heating the solution to allow evaporation of the water, increasing the solids concentration to 10% or more, depending on recipe requirements. This can be especially useful for applications in which
emulsification and
viscosity are more important characteristics than
foamability. The concentration of soluble solids can also be tailored to produce a more stable foam, using less aquafaba, by scrupulously filtering non-soluble material from the solution and also by adjusting the concentration to the application at hand. All else being equal, the concentration of aquafaba will vary according to: • processing methods (prior industrial dehydration, pre-soaking) • cooking conditions (pH, temperature, pressure and duration) • legume variety (e.g.,'Kabuli' vs 'Desi'
chickpeas) • miscellaneous additives • protein concentration • carbohydrate type (sugar vs fibre) and concentration ==Gallery==