Small molecule saponins are highly physiologically active and exert their biological effects only when interacting with biomolecules in the target cells in the human body. α-Lactalbumin (α-LA) is a globular protein that binds to hydrophobic ligands and has been used as a functional ingredient in the food industry. In this study, the interaction between two types of saponins (dammarane-type and oleanane-type) and α-LA was investigated using computer simulations, and their interaction patterns were imaged. The molecular docking results showed that each type of saponins binds to amino acid residues within the active pocket of α-LA via hydrophobic interactions and hydrogen bonding. However, dammarane-type saponins are more complex in structure, providing more binding sites, and they form hydrogen bonds via greater force.

Oil bodies (OB) are subcellular organelles that store lipids in plant seeds, which are composed of neutral triacylglycerol (TAG), a monolayer of polar phospholipids surrounding TAG, and proteins embedded in the phospholipid membrane. The composition and unique structure of OB make it have good oxidation stability. OB can be extracted by water extraction and enzyme-assisted extraction. As a natural pre-emulsified oil-in-water emulsion, OB emulsions have been gradually used to replace synthetic oil droplets and are promising for broad applications in the fields of food, medicine and animal husbandry. Therefore, it is of practical significance to explore the effects of OB composition and structure as well as environmental factors on the oxidation stability of OB emulsions. In this paper, the composition, structure and extraction process of OB, the oxidation stability of OB emulsions and future prospects for its application in the food field are reviewed, which can provide a reference for the development and utilization of OB.

Most high-protein nutrition bars (HPNBs) would harden during storage, seriously affecting the acceptability of consumers. In this work, soy protein isolate (SPI), extruded at 50, 75, 100, 125, and 150 ℃, was formulated for HPNBs to investigate whether extrusion protein could relieve hardening and improve quality characteristics of HPNBs during 45 days of storage at 37 ℃. HPNBs prepared with extruded SPI were notably softer. And they had higher sensory scores than HPNBs produced with unextruded SPI during storage (P < 0.05). But there were no significant differences in hardness and total color change with the increase of extrusion temperature after 45 days of storage (P > 0.05). According to the correlation analysis, HPNBs prepared by SPI extruded at 50 ℃ had the best physicochemical properties. This study provides an effective way to relieve the hardening of HPNBs during shelf life or even longer.