• Nutrient-functional double emulsions of encapsulated low molecular weight oyster-peptides (LOPs) were prepared. • LOPs double emulsion with good stability were obtained by ultrasonic treatment. • Ultrasonic treatment improved the sensory acceptance of LOPs in a double emulsion. • Cavitation effect of ultrasound improves the storage stability of LOPs double emulsion.

Starch‐containing foods with a high glycemic index and deficiency protein cannot meet the consumers’ proactive demand. Thus, the objective of this work is to test the effect of the presence of grass carp protein hydrolysates (GCPHs) on the digestive and structural properties of pristine rice starch (PRS) during the treatment of high pressure homogenization in combination with spray‐drying (HPH‐SP), and its possible mechanisms. The results show that, when the mass ratio of PRS: GCPHs increases from 100:0 to 100:15 during HPH‐SP treatment, the presence of GCPHs significantly increases the contents of slowly digestible starch (SDS) from 7.8 to 23.0%, and resistant starch (RS) from 10.7 to 25.3% in PRS‐GCPHs complexes after gelatinization, respectively. Structures based on SEM, XRD, ATR‐FTIR, and SAXS show that, compared to HPH‐SP treatment alone, HPH‐SP treatment in the presence of GCPHs can remarkably destroy crystallinity, shorten branch chain content, lower the IR ratio of 1045/1022 cm⁻¹, bragg spacing and lamellar peak intensity of PRS, and strengthen rigidity of PRS‐GCPHs complexes granules, which can play a significant role in increasing the contents of SDS and RS. Moreover, gelatinized PRS‐GCPHs rapidly assembles and aggregates to form more space hindrance and inhibit amylase close to leaching amylose, chained, or even branched amylopectin, which can be also attributed to the increased contents of SDS and RS authenticated by the observations of RVA, AFM, and representative images. These findings suggest that the presence of GCPHs during HPH‐SP treatment can be potently employed for preparing in vitro low digestible starch.

Highland barley (Hordeum vulgare L. HB) has been demonstrated to have a series of dietotherapy values, including being low fat, low sugar, high fiber, and especially high in β-glucan. Long-term consumption could reduce the incidence of chronic diseases and metabolic syndromes. In this study, the regulating effect of modified highland barley (MHB) products, namely microwave fluidized HB, extruded and puffed HB, and ultrafine pulverized HB on lipid metabolism and liver injury in mice fed a high fat and cholesterol diet (HFCD) was investigated using microbiota diversity gene sequencing and untargeted metabolomics. A total of six groups of mice were supplemented with a normal diet or an HFCD, with or without MHB, and the experimental period lasted 10 weeks. The obtained results demonstrated that MHB supplementation could effectively reverse the increase in body weight gain and adipose tissue accumulation caused by an HFCD (p < 0.05). Moreover, serum biochemical parameters showed that MHB supplementation significantly decreased total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) levels, while increasing high-density lipoprotein cholesterol (HDL-C) levels. The results of hematoxylin and eosin (H&E) assays showed that MHB supplementation could significantly improve the liver injury and adipose tissue accumulation. In addition, 16S rRNA amplicon sequencing showed that MHB supplementation increased the bacteroidetes/firmicutes ratio and the abundance Lactobacillus abundance, while also decreasing the Proteobacteria abundance, which are bacteria closely associated with the hyperlipidemia caused by HFCD. LC-MS metabolomics indicated that MHB supplementation significantly enhanced the levels of Deoxycholic acid, Myclobutanil, 3-Epiecdysone, 3,4-Dihydroxybenzeneacetic acid, and so on. In addition, MHB supplementation promoted activation of the Arachidonic acid metabolism pathways, the expression of ABC transporters, bile secretion, primary bile acid biosynthesis, and so on. Above all, this study showed the potential capacity of MHB to relieve hyperlipidemia and provides a reference for developing a new dietary intervention supplement to ameliorate hyperlipidemia.