Antinutritional factors
Chickpeas contain a variety of secondary compounds that can impair nutrient absorption from the gastrointestinal tract (Bampidis et al., 2011). Depending on the variety, chickpea seeds contain variable amounts of trypsin and chymotrypsin inhibitors that may decrease their feed value in pigs and poultry. Reported levels of inhibitors are in the 15-19 TIU/mg range, lower than that of raw soybeans (43–84 TIU/mg). Heat treatments, such as cooking or extrusion, reduce the amount of trypsin and chymotrypsin inhibitors (Bampidis et al., 2011; Batterham et al., 1990; Batterham et al., 1993).
Oxalic acid
Chickpea straw has been reported to have a high content of oxalic acid and to be unpalatable and possibly toxic (Suttie, 2000). However, studies do not confirm this.
Tannins
Chickpea pod husks contain a high amount of tannins, from 6 to 8% DM. The tannins-bound substrate of chickpea pod husks seems to be mostly carbohydrates (Sreerangaraju et al., 2000).