As an effective physical method for starch modification, ultrasonic treatment can significantly improve the chemical activity and quality of starch, but its mechanism needs to be further investigated. In this paper, ultrasonic‐modified cassava starch and octenyl succinic anhydride (OSA)‐modified cassava starch with low degree of substitution were prepared under ultrasonic conditions. The effects of ultrasound on the structure and properties of native cassava starch and the quality of OSA‐modified cassava starch were studied. The results showed that the crystallinity decreased from 30.7% to 26.4%, the reaction efficiency increased from 62.28% to 66.20%, and other characteristics also changed after 1 min of ultrasonic treatment. While the structure and properties of cassava starch changed differently after ultrasonic treatments for 8 min and 32–60 min. Consequently, these changes showed that ultrasonic treatment had a significant mechanochemical effect on starch granules. The quality of OSA‐modified cassava starch was improved significantly and its influence mechanism was analyzed by the mechanochemistry theory. Practical applications During the esterification of starch, the dense arrangement of crystalline regions limits the reaction of esterifying agents with starch granules. This study showed that ultrasound exerted strong mechanical forces on starch granules, which promoted the production of free radicals and increased the free energy of starch molecules. Besides, the increase of mechanochemical active sites in starch granules was conducive to the homogeneous reaction of octenyl succinic anhydride (OSA) and starch molecules. Therefore, the quality of OSA‐modified cassava starch prepared by ultrasonic‐assisted treatment was significantly improved. This study provides a reference for the application of ultrasonic technology in other fields and also lays a theoretical basis for the industrial development of high performance‐modified starch.

Zinc is an essential trace element in the human body and it participates in various pathways of metabolism. Cordyceps sinensis is a wellknown traditional Chinese medicine that contains cordycepin, cordycepic polysaccharides, proteins, vitamins, trace elements, and many other biological active materials. In this study, we cultured C. sinensis in liquid medium containing Zn ions and then analyzed the biomass, the ratios of total Zn accumulation, and the organic Zn content in the mycelia. The results showed that when the media contain 150 mg/L Zn, the biomass of mycelia of C. sinensis reached 10.7 g/L and the Zn content present in the mycelia reached 4875.1 microg/g. The percentage of Zn accumulated in the mycelia was 34.05% of the total Zn in the media, of which the organic Zn accounted for 76.33%. The results also revealed that the content of total amino acid (TAA) and essential amino acid (EAA) in the mycelia were increased substantially TAA and EAA in the Zn-treated mycelia were 11.1% and 15.2% higher, respectively, than that in the mycelia without Zn treatment. These results will be useful for elucidation of the physiological mechanism of Zn effects on the biological metabolism in the mycelia of C. sinensis.

The purpose of this study is to reveal the mechanism of preparing high quality modified starch by ultrasonic technology. In this paper, ultrasonic modified starch and octenyl succinic anhydride modified starch with low degree of substitution were prepared under ultrasonic conditions, using sweet potato starch as raw material. The effects of ultrasound on the structure and properties of native sweet potato starch were studied to see whether ultrasound could produce mechanochemical effect on starch. Then the mechanism of ultrasonic effect on quality of octenyl succinic anhydride modified starch was studied by mechanochemical effect. The results showed that after ultrasonic treatment for 1 min, the crystallinity decreased from 37.6 to 33.8% and reaction efficiency increased from 49.43 to 54.39%, while after ultrasonic treatments for 8 and 32–60 min had different changes. These changes showed that ultrasonic treatment produced significant mechanochemical effect on native sweet potato starch. Ultrasound significantly improved the quality of octenyl succinic anhydride modified starch, and its influence mechanism was revealed using the theory of mechanochemistry. This study provides a feasible method for the research of high quality modified starch and lays a theoretical foundation for expanding the application of ultrasound in various fields.

Traditional fermented foods harbor microbes that transform raw food components, improving their nutritional, shelf life, organoleptic, and health-promoting characteristics. Fermented foods are an important conduit of contact between bioactive components that act like antigens and the human body system. Versatile microbes in traditional fermented foods are associated with many health-promoting end-products, including dietary fatty acids and inherent fermenting microbial cells. Evidence shows that dietary fatty acid components regulate genes in a hormonally dependent manner, either directly via specific binding to nuclear receptors or indirectly by changing regulatory transcription factors. Fatty acids are implicated in anti-inflammatory, anti-obesogenic, immunoregulatory, cardioprotective, etc., activities. Challenges with scaling the production of traditional fermented foods stem from losing effective consortiums of microbial groups and the production of differential end-products. Industrialists scaling the production of traditional fermented foods must overcome safety and consistency challenges. They need to combine processes that lessen the advent of public health issues and introduce omics technologies that identify and maintain effective consortium groups, prune genes that code for toxic products, and inculcate microbes with additional beneficial characteristics. Incorporating omics in production will avail the benefits of traditional fermented foods to a larger population that craves them outside their native areas.

To investigate the effects of superfine grinding technology on dandelion tea powders (DTPs), the 80-mesh coarse and 200-mesh superfine dandelion tea powder (DTP) were prepared. A laser particle size analyzer (LPSA), scanning electron microscopy (SEM), colorimetry, and UV-vis spectrophotometry were used to compare the differences in physicochemical properties such as particle size distribution, degree of cell breakage, fluidity and filling properties, color differences, solubility in water, total acid phenol, and flavone levels and antioxidant activities. Our results showed that the 200-mesh superfine DTP with the smaller particle size showed better performance in the tests, and may help to establish a foundation for research and development of dandelion tea.