A Review of Processing Methods to Remove Alpha-Galactosides from Pulses

Pulses are rich in protein and fibre and are a staple food in developing countries. However, their inclusion in the Western diet has been limited due to the presence of flatulence factors, called alpha-galactosides. In order to remove these flatulence factors, there are a wide variety of processing methods that can be applied to pulses, that can transform them into a more nutritional product. This review discusses each processing method in detail, as well as the factors that contribute to the removal or degradation of alpha-galactosides in various pulses. Each pulse contains a different composition of alpha-galactosides, which affects their removal. The processing methods can be classified according to how they remove the alpha-galactoside: by extraction, thermal degradation, enzymatic degradation, or radiolytic degradation. Enzymatic degradation methods such as fermentation and germination were found to remove all or almost all alpha-galactoside content from pulses, however they also introduce undesirable flavors and aromas. Soaking is a well-tested method for many different pulses, however in order to achieve maximum removal, factors such as water temperature, soaking time, and addition of treatments like high pressure should be optimized. Future studies should continue to focus on combining methods to achieve maximum removal with little energy expenditure or development of undesirable compounds.