Extraction of dietary fiber from asparagus and its appliance in the bread

Dietary fiber was extracted from the stem of asparagus and added into bread to improve its quality and enhance its health function.Dietary fiber was extracted with alkali and the technology was tested by orthogonal design.The best condition was 1∶20 of material/liquid(w/v) with 0.5% of alkali liquor at 70 ℃ for 210 min.In this condition,11.96% of soluble dietary fiber was extracted,which showed that the heels in the process of asparagus contained abundant dietary fiber.Insoluble and soluble dietary fiber were added into bread at the amount of 3%,6% and 9%,and the sensory quality,specific volume,hardness,degree of aging,moisture content and weight loss during the storage were tested.The results showed that 6% of soluble dietary fiber exhibited best sensory quality and could improve the quality of bread while the quality was worse with the increment of insoluble dietary fiber.So,dietary fiber could improve the quality of bread,but the amount must be controlled.