Thermally treated soya bean oleosomes: the changes in their stability and associated proteins

Abstract

Oleosomes are subcellular organelles present naturally in plant seeds for storing lipids. Oleosomes can be used in the preparation of various food products, such as creams, salad dressings, mayonnaise and emulsion. However, food products are always subjected to thermal processing, and therefore, the evaluation of the thermal stability of oleosomes is of great important. The present work aimed to understand the effect of soya bean oleosome-associated proteins (SOAPs) on the thermal stability of soya bean oleosome emulsion (SOE). SOE was thermally treated for 15 min at different temperatures of 65, 75, 85 and 95°C. The confocal laser scanning microscope (CLSM) and Cryo-SEM of SOE, and as well as fluorescence spectroscopy, circular dichroism of SOAPs were investigated. The stability of SOE was significantly affected by thermal treatments, by modulating the conformational structures of SOAPs, while the composition changed slightly. The results of particle size, zeta potential and CLSM showed that thermal treatments caused aggregations of oleosomes especially at high temperatures (75-95°C). Thermally treated oleosomes were observed to have a rough surface. Results of this work are useful for understanding the underlying mechanisms of SOAPs in maintaining the thermal stability of SOE.

Effect of pasteurization on membrane proteins and oxidative stability of oil bodies in various crops

“…Post pasteurization, the composition of the membrane proteins of the OBs obtained from the different crops varied (Fig 1). Based on previous reports, the membrane protein composition of soybean (Ding et al ., 2019), sunflower, peanut (Chen et al ., 2018; Zaaboul et al ., 2018), sesame and walnut (Yan & Zhou 2021) is shown in Fig. 1.…”

“…1c). The hydrophobic forces of the disulfide bonds and non‐disulfide covalent bonds between the proteins and fatty acids play an important role in the development of protein aggregation (Potes et al ., 2013; Ding et al ., 2019). In the reducing SDS‐PAGE, protein aggregation may be caused by the non‐disulfide bonds only as the disulfide linkages of the proteins decreased with the addition of β‐mercaptoethanol and SDS.…”

Oil bodies extracted from high-oil soybeans (Glycine max) exhibited higher oxidative and physical stability than oil bodies from high-protein soybeans

“…The protein content of soybean flour was determined by the Dumas nitrogen quantification method, and the protein content of the SOBs was determined according to a method previously reported. 20 Freeze-dried SOB samples (2 g) were dispersed in a 4% (w/v) SDS solution in DI water. The mixture was spun for 1 min and then centrifuged at 12 000g for 40 min.…”

Nature-Assembled Structures for Delivery of Bioactive Compounds and Their Potential in Functional Foods

“…In contrast, several studies have reported the relatively high heat stability of oleosomes. Crude extracts of soy and maize oleosomes showed high stability to coalescence even at temperatures as high as 90°C and for durations from 15 min to 1 h (Nikiforidis et al, 2011 ; Ding et al, 2020 ). However, the heat-treated oleosomes had a high degree of aggregation because of protein–protein interactions between non-oleosome proteins that adhered to the oleosomes (Nikiforidis et al, 2011 ; Chen et al, 2012 ).…”

“…However, the heat-treated oleosomes had a high degree of aggregation because of protein–protein interactions between non-oleosome proteins that adhered to the oleosomes (Nikiforidis et al, 2011 ; Chen et al, 2012 ). More extensive heat treatment at 100°C for 15 min caused extensive coalescence in soy oleosomes, suggesting significant structural changes in the interfacial layer at these temperatures (Ding et al, 2020 ). Thermal treatment tended to improve the oxidative stability of oleosomes, which was attributed to the denaturation of lipolytic enzymes (Chen et al, 2012 ; De Chirico et al, 2020 ).…”