Preparation, multi-scale structures, and functionalities of acetylated starch: An updated review

Acetylated starch has been widely used as food additives. However, there was limited information available regarding the impact of acetylation on starch structure and functionalities, as well as the advanced acetylation technologies. This review aimed to summarize current methods for starch acetylation and discuss the structure and functionalities of acetylated starch. Innovative techniques, such as milling, microwave, pulsed electric fields, ultrasonic, and extrusion, could be employed for environmental-friendly synthesis of acetylated starch. Acetylation led to the degradation of starch structures and weakening of the interactions between starch molecules, resulting in the disorganization of starch multi-scale ordered structure. The introduction of acetyl groups retarded the self-reassembly behavior of starch, leading to increased solubility, clarity, and softness of starchbased hydrogels. Moreover, the acetyl groups improved water/oil absorption capacity, emulsifiability, filmforming properties, and colonic fermentability of starch, while reduced the susceptibility of starch molecules to enzymes. Importantly, starch functionalities were largely influenced by the decoration of acetyl groups on starch molecules, while the impact of multi-scale ordered structures on starch physicochemical properties was relatively minor. These findings will aid in the design of structured acetylated starch with desirable functionalities.

Automated summary

This review summarizes the methods for starch acetylation and discusses the impact of acetylation on starch structure and functionalities. Innovative techniques can be used for environmentally friendly synthesis of acetylated starch. Acetylation degrades starch structures and weakens the interactions between starch molecules, resulting in the disorganization of starch multi-scale ordered structure. The introduction of acetyl groups improves the solubility, clarity, softness, water/oil absorption capacity, emulsifiability, film-forming properties, colonic fermentability, and reduces the susceptibility of starch to enzymes.