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As disposable plastic straws were banned in China, more biodegradable straws were invented. Under high temperature and pressure conditions, starch is pasted and the molecular hydrogen bonds between starch are broken. After adding chitosan, chitosan and starch can form new hydrogen bonds. Biodegradable starch-based straws were made from cassava starch and rice starch (weight ratio = 1:1) by extrusion technique. Chitosan (0%, 5%, 10%, 15% and 20%) was added to improve the mechanical properties of the straws and the effect of chitosan on the chemical, mechanical and water resistance properties of the starch-based straws was investigated. Color, transparency and water resistance of CR/CH (tapioca starch, rice starch and chitosan) straws containing different levels of chitosan. The color and water resistance of straws containing different levels of chitosan were superior to those of CR (tapioca and rice starch). The best mechanical properties and water resistance of starch-based straws were obtained when the chitosan addition was 5%. The addition of chitosan flattened the appearance of the starch-based straws and improved the mechanical properties and water resistance of the straws. The above structure can provide a reference for the application of starch-based materials.

Pine pollen is rich in unsaturated fatty acids. However, unsaturated fatty acids are oxidized during processing. The oxidation of lipids may affect the odor of pine pollen. Different sterilization methods have different effects on lipid oxidation. In this study, we found that electron-beam sterilization is superior to ultra-high temperature sterilization in odor preservation. Using gas chromatography-mass spectrometry, volatile components were identified in electron-beam sterilization and ultra-high temperature sterilization processed pine pollen. Furthermore, the loss of vitamin C and polyphenols in the processing aggravated lipid oxidation, which made the odor of pine pollen worse. Moreover, lipid oxidase can accelerate lipid oxidation, thus affecting the odor of pine pollen, which was not conducive to the preservation of pine pollen. The results suggested that the components of unpleasant odor were identified as volatile aldehydes and volatile acids, and the odor was mainly produced by the oxidation of linoleic acid.