The objectives of this study were to evaluate the effect of varieties and heat processing methods on molecular structural, physicochemical, and nutritional characterization of feed chickpeas; evaluate the effect of heat processing methods, dry heat, wet heat and microwave irradiation processing method on feed chickpeas as an alternative source for protein and energy feed for ruminant livestock. To reveal the molecular structure spectral profile of chickpeas varieties and the molecular structure changes when applied heat processing methods, vibrational molecular spectroscopy was applied. Feed chickpea samples were determined for chemical profile, energy values, carbohydrate fractions. Subsequently, chickpea samples were incubated in the rumen of dairy cows for degradation kinetics analysis of nutrients. The intestinal digestion of feed chickpea samples was determined using three-step in vitro method with pre-incubation at 16h. Later, protein and carbohydrate related molecular spectral features before and after incubation were performed using vibrational ATR-FTIR molecular spectroscopy. The interactive relationship between processing induced molecular spectral profile changes and nutrient metabolism and availability were studied. The available results showed that varieties and heat processing methods significantly impacted molecular structural, physicochemical, and nutritional characterization of feed chickpeas.