Horse chestnut starch: Structure, properties, modification and its applications-A review

Horse chestnut (Aesculus indica) is an underutilized nut, accounting for approximately 60 % of the total starch present in its seed. Horse chestnut has potentials as a source of commercially available starches since it is widely distributed in Asia, Japan, Europe, America and China with minimal input costs. As the major component of horse chestnut seeds, starch is considered as a cheap and sustainable carbohydrate source in comparison to other conventional sources. Herein, this review aims to highlight the composition, isolation methods, structural characteristics, functional properties and modifications as well as potential applications of horse chestnut starch. Horse chestnut starch has high amylose content (33.1 %) renders it a promising source of resistant and low digestible starch. The structural characteristics of horse chestnut starch differs from other common starches, influencing its swelling power, solubility, transparency, freeze-thaw stability, pasting, gelatinization and retrogradation. However, Horse chestnut starch exhibits distinctive structural profile with high short chains, which correlates with its pasting viscosity. To increase its versatility and applicability, horse chestnut starch has been modified by physical, chemical and enzymatic treatments. This review also provides a basis for utilizing horse chestnut starch in food and non-food fields. To expand its potential utilization, future research demands on horse chestnut starch are also discussed.