In this study, five C18 fatty acids (FA) with different numbers of double bonds and configurations including stearic acid (SA), oleic acid (OA), elaidic acid (EA), linoleic acid (LA), and α-linolenic acid (ALA), were selected to prepare highland barely starch (HBS)-FA complexes to modulate digestibility and elaborate the underlying mechanism. The results showed that HBS-SA had the highest complex index (34.18 %), relative crystallinity (17.62 %) and single helix content (25.78 %). Furthermore, the HBS-C18 FA complexes were formed by EA (C18 FA with monounsaturated bonds) that had the highest R 1047/1022 (1.0509) and lowest full width at half-maximum (FWHM, 20.85), suggesting good short-range ordered structure. Moreover, all C18 FAs could form two kinds of V-type complexes with HBS, which can be confirmed by the results of CLSM and DSC measurements, and all of them showed significantly lower digestibility. HBS-EA possessed the highest resistant starch content (20.17 %), while HBS-SA had the highest slowly digestible starch content (26.61 %). In addition, the inhibition of HBS retrogradation by fatty acid addition was further proven, where HBS-SA gel firmness (37.80 g) and aging enthalpy value were the lowest, indicating the most effective. Overall, compounding with fatty acids, especially SA , could be used as a novel way to make functional foods based on HBS.
The self-assembly properties of long-chain C 18 fatty acids salts have good application in the field of environmental protection, drug control relieve, renewable energy and so on. Their degree of unsaturation is varied from saturated, monounsaturated to polyunsaturated fatty acids , which influence their self-assembly behaviors. Moreover, different external stimuli can also affect different self-assembly behaviors. In this work, three different fatty acids (stearic acid, C 18:0 ; oleic acid , C 18:1 ; linoleic acid , C 18:2 ) were chosen as the building blocks to self-assemble with arginine, a basic amino acid . The phase behaviors of ion-pairing systems affected by pH, temperature and solvent were investigated based on diagrams in more detail. The rich phase transition was observed through the characterization by cryogenic-transmission electron microscopy (cryo-TEM), polarizing microscopy , particle size analysis and rheological properties. We hope that the phase transition (self-assembly behaviors) controlled by these external conditions may provide a good guide for many related fields.
危险品化学品经营许可证（带存储）