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The excessive water sensitivity of hydroxypropyl methylcellulose (HPMC) films prevent them from being used extensively. In order to overcome this limitation, superhydrophobic HPMC films were meticulously crafted through the utilization of a composite of polydimethylsiloxane (PDMS) and ball-milled rice starch, corn starch, or potato starch (RS/CS/PS) for the coating process. Initially possessing hydrophilic properties, the HPMC Film (CA = 49.3 ± 1.8°) underwent a transformative hydrophobic conversion upon the application of PDMS, resulting in a static contact angle measuring up to 103.4 ± 2.0°. Notably, the synergistic combination of PDMS-coated HPMC with ball-milled starch demonstrated exceptional superhydrophobic attributes. Particularly, the treated HPMC-based film, specifically the HP-CS-2 h film, showcased an impressive contact angle of 170.5° alongside a minimal sliding angle of 5.2°. The impact of diverse starch types and the ball milling treatment on the PDMS/starch coatings and HPMC film was thoroughly examined using scanning electron microscopy (SEM), wide-angle X-ray diffraction (WAXS), and particle size analysis. These studies demonstrated that the low surface energy and roughness required for the creation of superhydrophobic HPMC-based films were imparted by the hierarchical structure formed by the application of PDMS/ball-milled starch. Polydimethylsiloxane (PubChem CID: 24764); Hydroxypropyl methylcellulose (PubChem CID: 671); Ethyl acetate (PubChem CID: 8857). [Display omitted] [ABSTRACT FROM AUTHOR]

Quinoa starch was developed as a new kind of Pickering emulsifier by enzymatic modification. The morphological structure, crystalline structure, lamellar structure, fractal structure, particle size distribution, contact angle, emulsion index (EI), and emulsion micromorphology were studied to explore the relationship between structure characteristics, hydrophilic property, and emulsifying properties of enzymatically modified (EM) quinoa starches. With the increasing enzymatic hydrolysis time in the test range of 0–9 h, particle size of EM quinoa starch decreased, and the broken starch and contact angle of EM quinoa starch increased; the EI value of emulsions with EM quinoa starch increased, and the oil droplet size of emulsions with EM quinoa starch decreased. It suggested that both the smallest particle size and the closest extent of the contact angle to 90° derived the best emulsifying property of EM-9. The EM quinoa starch had higher emulsifying capacity at higher oil volume fraction (Φ) (50%) than at lower Φ (20%), proving that the EM starch has potential to be used as Pickering emulsifiers in higher oil products, such as salad dressing. [ABSTRACT FROM AUTHOR]