Emerging Technologies for the Extraction and Modification of Dietary Fiber

Dietary fiber (DF) obtained from fruits, vegetables, cereals, and algae has nutritional benefits and functional properties. The incorporation of these materials results in food products with a reduced calorie, cholesterol, and fat content. DF also serve as functional ingredient improving hydration, oil holding capacity, viscosity, texture, sensory quality, and shelf-life. The extraction and modification of DFs can convert low-cost, undervalued byproducts into functional nutritional ingredients with high market value. Novel treatments, alone or in combination with conventional technologies, can improve the yield of DFs and retain or enhance their functionality. Microwave-heating, pressurized hot water, ultrasounds (US), and high hydrostatic pressures processing (HHP) reduce processing time and temperature, decrease the use of solvents, and enhance the recovery and functionality of DFs. Post DF extraction treatments, including particle size reduction, US and HHP, can be used to improve the functionality of DFs through the modification of their soluble and insoluble content. Processing by emerging technologies can also cause changes of the structural, rheological, and physicochemical properties of the native DF structure. DF modification by emerging technologies and its impact on the properties of DF-enriched ingredients and foods are reviewed in this chapter.