Carbohydrate and protein fractions of mesquite ("Prosopis juliflora" (Sswartz) D. C.) pods meal and its different component parts

Abstract

The objective of this study was evaluate the chemical analyses, in vitro dry matter true digestibility (IVTDMD) and carbohydrate and protein fractions of mesquite pods meal treated (80°C/10 - 12 h) or without heat treatment (FVACTT e FVASTT, respectively), and from the component parts of the pods. The treatments were: exocarp (EXVA), mesocarp and endocarp (EMVA), seeds (SVA) and the pod meals submitted or not to heating. Nitrogenous fractions were divided into fractions: “A” (non protein nitrogen; NPN), “B1” + “B2” (true protein fractions with fast and intermediate enzymatic degradations), “B3” (true protein fraction with enzymatic degradation) and “C” (indigestible protein). Total carbohydrates were estimated as follows: TC = 100 – (crude protein + ether extract + ash). Carbohydrate fractions were: “A” + “B1” (sugars and organic acids plus starch and pectin, respectively), “B2” (available fiber) and “C” (indigestible fiber). Crude protein values were: FVASTT 8.89%, FVACTT 8.72%, SVA 44.22%, EMVA 9.69%, EXVA 8.45%. Structural carbohydrate values were: FVASTT: 28.34% for NDF and 17.74% for ADF and for FVACTT: 31.52% NDF and 18.46% ADF. IVTDMD result for FVASTT was 73.04%, while for FVACTT was 69.21%. Nitrogenous fractions in mesquite pods meal indicated higher contribution of fractions “A”, “B1” and “B2”. Heat treatment of mesquite pods meal raised the cellular wall component values and unavailable fibrous fractions, which reflected negatively on its IVTDMD. Different component parts of mesquite pods meal showed similar results for their chemical analyses and for carbohydrate and protein fractions, except for seeds.