In these studies,lower Mw(1 and 5kDa;both DD=95%)and higher Mw (30 and 120 kDa; DD = 92% and 85%, respectively) chitosans were dissolved in 0.3% lactic acid, and added to dough at 0.01%, 0.1%,0.3%,and 0.5%concentrations.Chitosans with higher MW(30 and 120 kDa) were better than those with lower Mw (1 and 5 kDa) in extending the shelf life of bread.