The impacts of dietary nutrient intakes on brain development during the early life have been investigated extensively. As walnuts have been historically considered beneficial for cognition, this study was set to determine the mechanism by which unsaponifiable matter (USM) of walnut oil enhances neurodevelopment. In human induced pluripotent stem cells (hiPSCs), and human cerebral organoids, USM facilitated the proliferation and differentiation of neural stem cells (NSCs). This was associated with the changes of expression of genes related to neurodevelopment and cognition, particularly those regulating the Wnt signaling pathway. Here, data derived from hiPSCs, human cerebral organoids clearly show that USM administration enhances neural development. These findings may provide intervention strategies for early life neural problems in the future.

Sarcoplasmic-calcium-binding protein (SCP) was isolated, purified and identified from Penaeus vannamei. Meanwhile, its physicochemical properties (immunoactivity, thermal stability, pH stability and digestive stability), secondary structures and epitopes were studied. The results showed that the purified protein, which was obtained by successive steps of crude protein extraction, ammonium sulfate fractionation and anion exchange chromatography and exhibited a molecular mass of 21.6 kDa, was identified as SCP with a peptide coverage of 93.26%. SCP had strong immunoactivity, which decreased during heat treatment (≥ 65 ℃) and under strongly acidic and alkaline conditions. SCP had strong stability against intestinal fluid digestion, but poor stability against gastric fluid digestion. The secondary structure of SCP consisted of 26% α-helix, 16.9% β-sheet, 17.5% β-turn, and 39.6% random coil. Eight epitopes in SCP were predicted and identified using bioinformatics tools combined with immunological techniques.

This study investigated the impact of a new walnut processing technology on the quality and flavor of walnut oil in order to provide a theoretical basis for the development and application of this technology. Kernels from walnuts with green husks subjected to pre-drying treatment at 25, 120, 150 and 200 ℃ followed by natural drying and those treated directly by natural drying as a control were compared for their sensory quality, walnut oil quality, volatile organic compounds (VOCs). The results showed that pre-drying treatment resulted in higher overall sensory score of walnut kernels, the highest score of 34 being observed with pre-treatment at 150 ℃ for 60 min. Meanwhile, compared with the control, it increased the relative content of oleic acid in walnut oil and decreased the relative contents of linoleic and olenic acids. The relative content of unsaturated fatty acids in walnut oil was over 91%, the ratio of ω-6 to ω-3 polyunsaturated fatty acids (PUFAs) was within a reasonable range, and the basic physicochemical indicators met the national standards, indicating rich nutrition and good quality. Furthermore, pre-drying treatment increased the contents of most VOCs in walnut kernels. Walnut kernels pre-treated at 150 ℃ for 60 min contained the most abundant VOCs, and showed increased contents of aldehydes, ketones and heterocyclic compounds and decreased contents of alcohols, acids and esters compared with the control group. However, there was no significant difference in the content of terpenes between them. A partial least square-discriminant analysis (PLS-DA) model was generated based on the gas chromatography-ion mobility spectrometry (GC-IMS) results, which could well differentiate among walnut kernels with different pre-drying treatments, and 18 compounds were selected as the key VOCs affecting the flavor characteristics of walnut kernels with pre-drying treatments.

Organoids are three-dimensional cell cultures that possess some key properties of organs, and their application in food science research has been increasingly emphasized. This paper introduces the current status of the construction and functional characterization of three major organoids, namely, intestinal, liver and brain organoids, describes recent progress in the application of intestinal, liver and brain organoids in the field of food science, discusses future prospects for the integrated application of organoids with cutting-edge technologies such as microarray technology and microfluidics, and analyzes the challenges and future directions for the application of organoid models in food science. We hope that this review can provide a reference for promoting the research and application of organoids in the field of food science.

This study prepared and structurally characterized peptides with different molecular masses from walnut meal protein by enzymatic hydrolysis with a mixture of two proteases followed by ultrafiltration, and it also explored the antioxidant activities of walnut peptides and their protective effects on oxidative damage in HepG2 cells. The results showed that the antioxidant activity of walnut protein hydrolysate (WPH) with molecular mass < 1 kDa was the strongest, with half-maximal inhibitory concentration (IC₅₀) of 11.47, 35.67 and 49.72 mg/mL for hydroxyl radical, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging capacity, respectively. Moreover, the < 1 kDa walnut peptide fraction could reduce the reactive oxygen species (ROS) content and increase the superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GSH-Rx) and glutathione peroxidase (GSH-Px) activity in HepG2 cells. The walnut peptide was irregular in shape and had a smooth surface and dense structure with numerous rough patterns and pores. The walnut peptide had a maximum absorption peak at 225 nm wavelength. The most abundant secondary structures of the walnut peptide were random coil (36.5%) and β-sheet (36.6%). These results indicate that the < 1 kDa walnut peptide has a protective effect against oxidative damage in HepG2 cells.