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Sorghum is gaining recognition as a gluten-free grain and is a safe alternative for those suffering from gluten sensitivity or celiac disease. Still, the lack of gluten proteins does not allow sorghum to form a viscoelastic dough.  In this study, reducing agents were added to improve the functional properties of sorghum kafirin proteins for bread baking. Study objectives were to determine the effect of reducing agents on kafirins, batter consistency and physical characteristics of sorghum bread. The reducing agents used were L-cysteine (2.5% fwb) and sodium metabisulfite (SMB) (500 ppm fwb).  Following the method described by Bean et al (2011), RP-HPLC protein analysis showed that L-cysteine and SMB reduced protein structure, increasing RP-HPLC total peak area up to 747% and 681%, respectively. Batter consistency, obtained using RVA (AACCI Method 76-21.03) showed L-cysteine increased peak and breakdown viscosities and decreased final viscosity. Samples treated with SMB had increased peak viscosity, holding strength and final viscosity while breakdown viscosity decreased.  Yeast activity, measured by Risograph using AACCI Method 89-01.01, revealed that L-cysteine reduced yeast activity after 20 min while SMB had no effect. Sorghum bread was baked using the method of Schober et al (2005).  Loaf volume was measured by rapeseed displacement (AACCI Method 10-05.01) and bread firmness was evaluated using AACCI Method 74-10.02.  In vitro pepsin digestibility (IVPD) was determined using the method of Mertz et al (1984).  Loaf volume and crumb grain characteristics of bread containing SMB were equal to the control, while initial firmness and staling were improved. The addition of L-cysteine decreased loaf volume but produced softer initial crumb and improved IVPD digestibility by 19%.