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China is the world’s largest walnut producer, with an annual output of 4.795 9 million tons. Walnut kernels have high nutritional value, containing 65%−69% of oil and 15%−20% of protein. Walnut meal, an abundant byproduct of walnut oil production, is mainly used in animal feed and fertilizers with low processing efficiency, whose potential for high-value utilization is far from being excavated. Studies have found that walnut meal contains a large amount of protein (42%−54%), its amino acid composition is rich, and the proportion of amino acids in walnut meal is suitable for human absorption. Walnut meal is a source of high-quality plant protein with a true protein digestibility score of 86.22%, and a biological valence of 98.77%. Therefore, high-efficiency utilization of walnut meal proteins is an important pathway for the high-value utilization of walnut meal. In this article, the composition, structure, and nutritional value of walnut proteins are reviewed. The extraction methods and functional characteristics of walnut proteins are summarized. The effect of modification on their functionalities and digestibility is also summarized. Finally, the application potential of walnut protein in foods is discussed.

In this study, the effect of component migration and interaction with concomitant saponins on the composition and functional properties of the seed storage proteins from Camellia oleifera Abel., a typical woody oil crop in China, was investigated using proteomics and molecular docking. The results showed that the optimal parameters for alkaline extraction were solid/liquid ratio 1:10 (g/mL) and pH 8.0, which resulted in an extraction rate of 75.8%, and a saponin-to-protein ratio of 2.60. The 11S globulins were precipitated at pH 4.5 with a saponin-to-protein ratio of 0.36. Albumin accounted for 69% of the total storage proteins, and coexisted with saponin during the extraction process, thus resulting in a high saponin-to-protein ratio of 3.73. The foaming properties of albumin and globulin from C. oleifera Abel. seeds were larger than 200%, and the emulsifying activity index was 16.7 m2/g. The interaction between saponins and proteins significantly improved the emulsion stability. This study provides theoretical support for the high-value utilization of proteins from C. oleifera Abel. and the development of functional food ingredients.

The structural heterogeneity and complexity of plant cell wall polysaccharides limit the release of phytonutrients in food processing, ultimately affecting the sensory quality, nutritional value, and shelf stability of products. Efficient enzymatic hydrolysis using plant cell wall polysaccharide-degrading enzymes (PCWPE) is a key step in overcoming the plant cell wall, a chemically complex structure composed mostly of polysaccharides, in food processing. PCWPE include cellulase, hemi-cellulase and pectinase, which specifically and efficiently hydrolyze glycosidic bonds in plant cell wall polysaccharides, significantly improving the sensory flavor and nutritional value of products, enhancing the stability of multiphase systems, and increasing the product yield. In recent years, PCWPE have been widely used in beverage processing, phytonutrient extraction, functional sugar preparation, and the processing of emerging sustainable plant-based food and thereby have become a research hotspot in the field of green food processing. This article summarizes the latest research on the mechanism of action of PCWPE, efficient enzymatic hydrolysis techniques and their application in the food industry, with a view to providing a reference for technological innovation in the field of high-quality plant-based food processing.

The plant milk market has a promising future and flavor is a critical quality attribute of plant milk. The good flavors of plant milk such as milky, fruity, nutty, and cereal-like aromas are well-liked by consumers, while the undesirable flavors such as bitterness, bean-like odor, green odor, and mushroom-like odor severely limit the development of the plant milk industry. Based on the current state of development and future trends in raw material screening and processing technology for plant milk production and research on the flavor composition of plant milk, this paper summarizes the methods used for the extraction and identification of volatile substances from plant milk and the material basis of its flavor composition, highlighting the formation pathways of aroma and off-odor, the interaction between macromolecules and small molecules in plant milk, and the influential factors of and the regulatory strategies for the formation of aroma and off-odor in plant milk. This review is expected to provide scientific research ideas and strategies for maximizing the preservation of the good flavor of plant milk and avoiding the generation of undesirable flavors.

Flaxseed is one of the eight major oil crops in China, and flaxseed oil is a healthy vegetable oil rich in α-linolenic acid, which is highly favored by consumers. Volatile flavor substances are a key attribute affecting the quality of flaxseed oil and its popularity among consumers. This article provides a systematic overview of recent advances in the research on volatile flavor substances in flaxseed oil, with a focus on the techniques and methods for the extraction, analysis and detection of volatile flavor substances in flaxseed oil from the perspective of molecular sensory science, the material basis and aroma characteristics of volatile flavor in flaxseed oil, and the factors affecting the flavor formation of flaxseed oil. Moreover, it also summarizes the possible formation pathways of some key flavor substances during the processing of flaxseed oil. It is hoped that this review will provide a theoretical basis for improving the flavor of linseed oil.

In this study, the effects of different mass fractions of whey protein isolate (WPI) on the physicochemical properties, physical stability, rheological properties and microstructure of Antarctic krill oil (AKO, 30%, m/m)-in-water emulsion were compared and analyzed. The results showed that the mean particle size and zeta potential of AKO emulsion without WPI were 516.67 nm and −14.03 mV, respectively. As the mass fraction of WPI increased from 0% to 6%, the mean particle size of the emulsion decreased by 42.28% (P < 0.05), and the absolute value of zeta potential significantly increased by 18.05% (P < 0.05). The physical stability of the emulsion was obviously improved. Shear rheological test showed that the apparent viscosity of the emulsion increased with an increase in WPI mass fraction. Microrheological test showed that the introduction of WPI in the emulsion system slowed down the droplet movement speed, increased the elastic behavior, and decreased the fluidity. The microstructure observation showed that WPI addition caused the emulsion to form a more complete and uniform network structure, binding more lipid droplets to maintain the stability of the emulsion. The excessive addition (greater than 6%) of WPI caused the flocculation of the emulsion, thereby weakening its stability. Therefore, the addition of appropriate amounts of WPI can effectively improve the stability of AKO emulsion by reducing the particle size, increasing the charge repulsion force of lipid droplets, and enhancing the viscoelasticity and protein network structure binding. This study is expected to provide guidance for constructing high-load and high-stability AKO emulsion system and broadening its application in health foods.