Systematic review on modification methods of dietary fiber

Each day huge amount of plants are consumed, thereby a lot of by-products are dumped into the ashcan directly which are rich in highly nutritious bioactive substances: dietary fiber (DF). DF, defined as the seventh nutrient for humans by nutritionists, has many benefits for our health, such as improve the intestinal flora, decrease the probability of obesity and cardiovascular disease, etc. Thus the study on the modification of plant DF to obtain the high yield and quality DFs (including the soluble dietary fiber and insoluble dietary fiber) has always be a hot topic in the field of functional food processing. However, to the best of our knowledge, no study has systematically analyzed the difference between different modification methods of DF. In this paper, the modification methods (physical method, chemical method, biological method and combined method) for DFs which have been explored by researchers in the last decade are reviewed, and the different effect caused by different modification methods on functional properties of DFs are summarized. Moreover, the modification mechanism, comparative analysis and future trends of different methods for DFs are discussed. This review might provide guidance for selecting appropriate DF modification method, and achieve better industrialization to modify the DFs. Meanwhile, this review will be beneficial to strengthen economic value and utilization of plant and its by-products to a greater extent, and significantly satisfy the growing demand of high yield and quality DFs.