The coating has been made of the cheap starch and it is resistant to acidic media and can be used in foodstuff and medical industries.

Starch is a cheap and biodegradable polymer that has attracted the attention of many researchers in the past few years for the prevention of foodstuff corruption. Therefore, this study tries to present an appropriate coating for maintaining the effects of food products by using starch nanocrystals. The coating does not have any undesired side effects on the environment or the consumer, and it can be used in hygienic products by having applications in the production of target delivery drugs.

The nanocrystals are prepared through the acidic hydrolysis of starch granule at room temperature, and therefore, they are resistant to acidic media. Toughness and low permeability are among other characteristics of the nanocrystals.

In this research, date palm pit extract has been used as the rich source of polyphenol and antioxidant, and it has been placed inside the nanocrystalline coating of starch. Food products containing phenol play an important role in many metabolism processes in the body, and in the prevention of diseases. Based on the results, the produced nanocrystals were 48 nm in size. The sizes of nanoparticles (before being placed inside the date palm pit extract) and nanocapsules (nanoparticles containing date palm pit extract) were reported to be 164 and 198 nm, respectively.