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In this study, peanut, sesame, and rapeseed oil bodies (OBs) were extracted by the aqueous medium method. The surface protein composition, microstructure, average particle size d 4 , &nbsp; 3 , ζ -potential of the extracted OBs in aqueous emulsion were characterized. The stability of the OB emulsions was investigated. It was found that different OB emulsions contained different types and contents of endogenous and exogenous proteins. Aggregation at low pHs (<6) and creaming at high pHs (7 and 8) both occurred for all of three OB emulsions. Sodium alginate (ALG) was used to solve the instability of OB emulsions under different conditions-low concentration of ALG improved the stability of OB emulsions below and near the isoelectric point of the OBs, through electrostatic interaction. While a high concentration of ALG improved the OB emulsion stability through the viscosity effect at pH 7. The OB emulsions stabilized by ALG were salt-tolerant and freeze-thaw resistant.

International dietary guidelines advocate replacement of saturated and trans fat in food with unsaturated oils. Also, there is growing interest in incorporating highly unsaturated omega-3 oils in to food products due to beneficial health effects. A major obstacle to incorporating highly unsaturated oils in to food products is the extreme susceptibility to oxidative deterioration. Oil bodies were prepared from tuna oil, oleosin, and phospholipid mimicking natural oil bodies within oilseed. Oleosin was extracted from canola (Brassica napus) meal by solubilization in aqueous sodium hydroxide (pH 12) and subsequent precipitation at its isoelectric point of pH 6.5. The tuna oil artificial oil bodies (AOBs) readily dispersed in water to produce oil-in-water (o/w) emulsions, which did not coalesce on storage and were amenable to pasteurization using standard conditions. Accelerated oxidation studies showed that these AOB emulsions were substantially more resistant to lipid oxidation than o/w emulsions prepared from tuna oil using Tween40, sodium caseinate, and commercial canola protein isolate, respectively. There is potential to use commercial canola meal, which is cheap and abundant, as a natural source of oleosin for the preparation of physically and oxidatively stable food emulsions containing highly unsaturated oils., (© 2013 Institute of Food Technologists®)

[Display omitted] Oleosomes are natural oil droplets with a unique phospholipid/protein membrane, abundant in plant seeds, from which they can be extracted and used in emulsion-based materials, such as foods, cosmetics and pharmaceutics. The lubrication properties of such materials are essential, on one hand, due to the importance of the in-mouth creaminess for the consumed products or the importance of spreading the topical creams. Therefore, here, we will evaluate the lubrication properties of oleosomes, and how these properties are affected by the components at the oleosome membrane. Oleosomes were extracted, and their oral lubricating properties were evaluated using tribology. To understand the influence of the oil droplet membrane composition, reconstituted oleosomes were also studied, with membranes that differed in protein/lecithin ratio. Additionally, whey protein- and lecithin-stabilised emulsions were used as reference samples. Confocal laser scattering microscopy was used to study the samples visually before and after tribological analysis. Oleosomes followed a ball-bearing mechanism, which was probably related to their high physical stability due to the presence of membrane proteins. When the membrane protein concentration at the surface was reduced, the droplet stability weakened, leading to plating-out lubrication. Following our results, we elucidated the oleosome lubrication mechanism and showed their possible control by changing the membrane composition. [ABSTRACT FROM AUTHOR]

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BACKGROUND: Soybean oil bodies (SOB) are naturally pre‐emulsified lipid droplets recovered directly from soybean seeds. Almost all food emulsions contain salts. However, it was not clear how the incorporation of salts affected the physicochemical stability of SOB. RESULTS: This study investigated the effect of NaCl (0–1.2%) on the physical and oxidative stability of SOB emulsions under neutral (pH 7) and acidic (pH 3) conditions. In the presence of NaCl, the SOB emulsion (pH 7) showed strong flocculation during storage due to electrostatic screening. The NaCl‐induced flocculation of SOB was attenuated at pH 3, which may be due to the difference in conformation or interaction of the protein interfaces covering SOB at different pH values. The increase in ionic strength or acid conditioning treatment resulted in a remarkable increase in the stability of SOB emulsions against coalescence. The confocal laser scanning microscopy images also confirmed the NaCl‐induced changes in the flocculation/coalescence properties of SOB. The oxidative behavior tests indicated that SOB emulsions containing NaCl were more susceptible to lipid oxidation but protein oxidation was inhibited due to electrostatic screening, which reduced pro‐oxidant accessibility of unadsorbed proteins in the emulsion. This oxidative behavior was attenuated at pH 3. CONCLUSION: The incorporation of NaCl significantly reduced the physical and oxidative stability of the SOB emulsion, and acidic pH mitigated NaCl‐induced flocculation and lipid oxidation of SOB. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Oil bodies (OBs) dispersed in an aqueous medium form a natural emulsion with high physical and microbiological stability. This work was focused on the development of a new protocol for extracting OBs from olive paste, through the extraction of an olive oil body cream (OOBC) with a yield of about 43% (wt/wt) in approximately 2 h. The proximate analysis revealed the presence of moisture, lipids and proteins as well as the contents of polyphenols and flavonoids, and the antioxidant powers were determined. The rheological and tribological performances of the OOBC were evaluated. Moreover, we measured a size distribution in the range of 0.7–1.7 m, by using a standard optical microscope. The results have demonstrated clearly that the OOBC extracted from the olive paste can be used as a functional and vegan ingredient in food emulsions. [ABSTRACT FROM AUTHOR]

Oleosomes are highly conserved organelles that store oil and can be utilized as a natural oil-in-water emulsion for food products when isolated intact. Although soybeans are a rich source of oleosomes, their potential has not been fully realized due to significant aggregation within the emulsion, which limits their applications. This study investigates the effect of homogenization as a strategy to prevent oleosome aggregation and coalescence. Our results indicate that homogenization at pressures of 10–30 MPa effectively prevents phase separation and preserves the initial particle size of oleosomes. However, at pressures of 40–50 MPa, oleosome particles are disrupted, leading to the formation of smaller particles that stabilize the emulsion against coalescence. We found that extracting oleosomes at a pH of 9 consistently produces stable emulsions, suggesting this method as a viable approach to enhance the stability of these emulsions. Furthermore, extraction at a pH of 7 followed by homogenization enhances the physical stability of the mixtures. Additionally, our findings demonstrate that performing extractions at pH 9 helps in preserving oleosome membrane-associated proteins, thereby further improving the stability and extending the storage potential of soybean oleosomes to up to 20 days. [Display omitted] • High-pressure homogenization can make stable soybean oleosome emulsions. • Oleosome extracted at pH 9 is more stable compared to the oleosome extracted at pH 7. • A homogenization pressure at 30 MPa or below can break the oleosome aggregates. • A homogenization pressure of 40 and 50 MPa leads to decrease the primary oleosome size. [ABSTRACT FROM AUTHOR]

The food industry is creating a diverse range of plant‐based alternatives to dairy products, such as milks, creams, yogurts, and cheeses due to the increasing demand from consumers for more sustainable, healthy, and ethical products. These dairy alternatives are often designed to mimic the desirable physicochemical, functional, and sensory properties of real dairy products, such as their appearance, texture, mouthfeel, flavor, and shelf‐life. At present, there is a lack of systematic testing methods to characterize the properties of plant‐based dairy alternatives. The purpose of this review is to critically evaluate existing methods and recommend a series of standardized tests that could be used to quantify the properties of fluid plant‐based milk alternatives (milk and cream). These methods could then be used to facilitate the design of milk alternatives with somewhat similar attributes as real dairy milk by comparing their properties under standardized conditions. Moreover, they could be used to facilitate comparison of the properties of milk alternatives developed in different laboratories. [ABSTRACT FROM AUTHOR]

Plants offer a vast variety of protein extracts, typically containing multiple species of proteins that can serve as building blocks of soft materials, like emulsions. However, the role of each protein species concerning the formation of emulsions and interfaces with diverse rheological properties is still unknown. Therefore, deciphering the role of the individual proteins in an extract is highly relevant, since it determines the optimal level of purification, and hence the sustainability aspects of the extract. Here, we will show that when oil/water emulsions were prepared with a rapeseed protein extract containing napins and cruciferins (in a mass ratio of 1:1), only napins adsorbed at the interface exhibiting a soft solid-like rheological behavior. The dominance of napins at the interface was ascribed to their small size (radius r = 1.7 nm) and its unique Janus-like structure, as 45% of the amino acids are hydrophobic and primarily located at one side of the protein. Cruciferins with a bigger size (r = 4.4 nm) and a more homogeneous distribution of the hydrophobic domains couldn't reach the interface, but they appear to just weakly interact with the adsorbed layer of napins. [ABSTRACT FROM AUTHOR]

The surface compositions and structure of oil bodies (OBs) are dependent on the oil crop, and these factors affect in vitro gastrointestinal digestion behaviors. Herein, a comparative study was conducted to examine the in vitro gastrointestinal digestion characteristics of two natural emulsions prepared with soybean seeds and rapeseed OBs during gastrointestinal digestion process. The average particle size of soybean OBs and rapeseed OBs emulsions was 0.46 and 5.02 Î?m, respectively. The droplet size of soybean seed and rapeseed OBs emulsions was large with relatively low zeta-potentials at 30 min digestion time in simulated gastric fluid condition. The droplet size of two natural OBs emulsions decreased with increasing digestion time in simulated gastric fluid condition. The average droplet size of both emulsions gradually decreased with increasing digestion time in simulated intestinal fluid conditions. The zeta-potential of the two emulsions increased with increasing digestion time in simulated intestinal fluid conditions. The extent of free fatty acids of soybean OBs emulsions was significantly higher than rapeseed after 20 min digestion time in simulated intestinal fluid conditions. The obtained results suggested that plant OBs could be useful as natural emulsifiers in the development of functional food and achieve controlled release of bioactive compounds from emulsions during gastrointestinal digestion. [ABSTRACT FROM AUTHOR]

Consumers are increasingly interested in decreasing their dietary intake of animal-based food products, due to health, sustainability, and ethical concerns. For this reason, the food industry is creating new products from plant-based ingredients that simulate many of the physicochemical and sensory attributes associated with animal-derived foods, including milk, eggs, and meat. An understanding of how the ingredient type, amount, and organization influence the desirable physicochemical, sensory, and nutritional attributes of these plant-based foods is required to achieve this goal. A potential problem with plant-based diets is that they lack key micronutrients, such as vitamin B12, vitamin D, calcium, and ω-3 fatty acids. The aim of this review is to present the science behind the creation of next-generation nutritionally fortified plant-based milk substitutes. These milk-like products may be formed by mechanically breaking down certain plant materials (including nuts, seeds, and legumes) to produce a dispersion of oil bodies and other colloidal matter in water, or by forming oil-in-water emulsions by homogenizing plant-based oils and emulsifiers with water. A brief overview of the formulation and fabrication of plant-based milks is given. The relationship between the optical properties, rheology, and stability of plant-based milks and their composition and structure is then covered. Approaches to fortify these products with micronutrients that may be missing from a plant-based diet are also highlighted. In conclusion, this article highlights how the knowledge of structural design principles can be used to facilitate the creation of higher quality and more sustainable plant-based food products.

[Display omitted] • Oil bodies (OBs) successfully loaded with curcumin (Cur) via ultrasonic and pH-driven. • Ultrasonic treatment was beneficial for the encapsulation and load of Cur. • Ultrasonic treatment improved the emulsion stability of Cur-loaded OBs. • Cur-loaded OB emulsions had the best stability and bioaccessibility at 200 W. In this study, oil bodies (OBs) loaded with curcumin (Cur) were successfully prepared via an ultrasonic and pH-driven method. Ultrasonic treatment significantly improved the encapsulation efficiency (EE) and loading capacity (LC) of Cur, producing OB particles with small size, uniform distribution, and high ζ-potential absolute values. When the ultrasonic power was 200 W, the EE, LC, and ζ-potential absolute value were the greatest (88.27 %, 0.044 %, and −25.71 mV, respectively), and the OBs possessed the highest yellowness, representing the best treatment result. The confocal laser scanning microscopy (CLSM) and cryo-scanning electron microscopy (cryo-SEM) results was also intuitionally shown that. Moreover, circular dichroism (CD) proved that ultrasonic treatment could unfold the surface protein structure, further enhancing the stability. Therefore, the cream index (CI), peroxide value (POV), and thiobarbituric acid reactive substances (TBARS) were the lowest when the ultrasonic power was 200 W. In this case, the Cur loaded in OBs was well protected against hostile conditions, evidenced by the highest Cur retention rate and the lowest degradation rate constant. Finally, the in vitro gastrointestinal digestion simulation results showed that the ultrasonic treatment effectively increased the release of FFA, bioaccessibility, and stability of Cur, especially when the ultrasonic power was 200 W. This research offers a new OB-based delivery system to stabilize, deliver, and protect Cur for food processing. [ABSTRACT FROM AUTHOR]

An aqueous process for the recovery of oil bodies from rapeseed using sodium bicarbonate-based soaking and grinding media (pH 9.5) was investigated. The effect of the ratio between seed and mass of media during grinding and molarity of the medium used on oil body integrity, purity and storage stability have been studied. The grinding of seeds in solution at a ratio of 1:7 (w/w) significantly improved the quality of oil body suspension to a size more in-line with that seen in vivo (average D 4,3 of 1.19 µm). The purity and the composition of the recovered oil bodies depends on the molarity of medium used; the use of a sodium bicarbonate solution (pH 9.5, 0.1 M) in the grinding and washing steps produced oil body preparations with the same purity as that resulting from washing a crude preparation with 9 M urea. The resultant emulsion had improved physical stability over a storage period of one month. [ABSTRACT FROM AUTHOR]

Oleosomes are natural oil droplets, present in all organisms and abundant in oilseeds. After their aqueous extraction from oilseeds, they can be directly utilized as oil droplets in food, cosmetics and all types of oil-in-water emulsion systems. However, to expand the potential uses of oleosomes as green ingredients and to valorize oilseeds as efficient as possible, we explored their emulsifying ability. Oleosomes were extracted from rapeseeds, and 10.0 wt% oil-in-water emulsions were created after homogenization with 0.5–6.0 wt% oleosomes, and the droplet size of the emulsions and their structure was measured by laser diffraction and confocal laser scanning microscopy (CLSM), respectively. The emulsion with an oleosome concentration lower than 1.0 wt% gave unstable emulsions with visible free oil. At oleosome concentrations at 1.5 wt% or higher, we obtained stable emulsions with droplet sizes between 2.0 and 12.0 µm. To investigate the role of the oleosome interfacial molecules in stabilizing emulsions we also studied their emulsifying and interfacial properties (using drop tensiometry) after isolating them from the oleosome structure. Both oleosomes and their isolated interfacial molecules exhibited a similar behavior on the oil-water interfaces, forming predominantly elastic interfacial films, and also showed a similar emulsifying ability. Our results show that oleosomes are not stabilizing the oil-in-water emulsions as intact particles, but they provide their interfacial molecules, which are enough to stabilize an oil-water surface up to about 2 times bigger than the initial oleosome surface. The understanding of the behavior of oleosomes as emulsifiers, opens many possibilities to use oleosomes as alternative to synthetic emulsifiers in food and pharma applications. [Display omitted] • Rapeseed oleosomes are natural droplets with a phospholipid-protein membrane. • An oleosome conc. of 1.5 wt% is enough to provide stable 10 wt% O/W emulsions. • The oleosome interfacial molecules stabilize the newly formed emulsion droplets. • Oleosomes have a potential as natural emulsifiers. [ABSTRACT FROM AUTHOR]

The physiochemical properties of peanut oil bodies were studied, which was reflected in zeta potential, particle size, and stability. Zeta potential of oil bodies changed from around +37.23 mV at pH 3 to −21.83 mV at pH 7. High temperature (95 °C) did not influence zeta potential and particle size whereas low temperature (−20 °C) lead to the increase in particle sizes of peanut oil body suspension at both pH 3 and 7. However, the effects of low temperature on the particle size were weakened by the addition of gum arabic (GA). Thus, the peanut oil bodies were proved to be a new useful source of lipids for application in emulsion system. The peanut oil bodies can be a food ingredient applied in food industry and gum arabic (GA) could enhance the stability of peanut oil body under several environments. [ABSTRACT FROM AUTHOR]

In order to explore the stabilization mechanisms of intrinsic protein (IP) and extrinsic protein (EP) in natural oil-bodies, the effects of adding EP and IP in different relative proportions on the stability, interfacial characteristics, and digestibility of artificial oil body (AOB) emulsions were studied. The stability test results showed that the AOB emulsion prepared using 40% EP/60% IP exhibited the highest ζ-potential (−36.3 mV) and storage stability. According to the results of interface properties, competitive adsorption occurred at the interface in the emulsions prepared using IPs and EPs. Furthermore, by measuring the bioavailability of free fatty acids and curcumin during the digestion process, it was elucidated that 40% EP/60% IP developed a stable interfacial membrane, which facilitated the targeted release of curcumin in the intestine and yielded higher bioavailability. These results lay the foundation for clarifying the stabilization mechanism of natural oil body emulsions from an interfacial perspective. • Interfacial properties of artificial oil-body (AOB) emulsions were investigated. • Stabilization of intrinsic (IP) and extrinsic (EP) proteins on AOBs was probed. • AOB emulsion with 40% EPs showed optimal stability-related properties. • A 3 , Bd 30K, and oleosin hindered interface replacement by bile salts and trypsin. [ABSTRACT FROM AUTHOR]

Soybean and peanut oil bodies (OBs) receive considerable interest in the food, cosmetic, and pharmaceutical industries. However, they aggregate easily because of their low ζ-potentials and weak electrostatic repulsion. Therefore, this study aimed to improve their stabilities using apple pectin (AP) under acidic conditions (pH 3.0, 5.0, and 7.0). The combined influences of pH and AP concentration on the interfacial proteins and rheological and physical properties were assessed. An AP concentration of 0.05% significantly reduced the storage stability of OBs at pH 3.0 (P < 0.05). The storage and oxidative stabilities of the emulsions with AP concentration ≥ 0.15% were improved by increasing the ζ-potential and apparent viscosity and decreasing the mean particle diameter. When the AP concentration was between 0.3% and 0.5%, the influence of AP on the stability of emulsion was steady. AP decreased the content of extrinsic proteins and increased the apparent viscosity. The emulsion showed superior stability at pH 5.0. Our findings indicate that AP exhibits potential as an OB stabilizer and may be used in yogurt-like foods and acidic dressings. [Display omitted] [ABSTRACT FROM AUTHOR]

This study proposes a new strategy for extracting lipids from Buriti fruit in the form of oleosomes (OB) using an alkaline extraction medium and also evaluates the stability of OB under different pH conditions. The extracted oleosomes were evaluated under three pH conditions (2, 4.5 and 7) and showed sizes between 14.33 ± 0.03 and 16.44 ± 0.08 μm. Their zeta potential values varied with increasing pH (from 2 to 9), with an isoelectric point between pH 2.0 and 3.0. Proteins associated with oleosomes were observed between 14 and 29 kDa. The stability of the oleosome emulsions was confirmed by measuring the droplet size (D 3,2) which showed constant values during 28 days of storage. The Turbiscan stability index (TSI) also corroborates the stability of these emulsions in the same storage period. Furthermore, the carotenoid content in the oleosome emulsions was more stable than the carotenoids in bulk Buriti oil during 28 days of storage. • Buriti oleosomes have considerable lipid concentration. • The oleosome emulsions remained stable for 28 days. • Buriti oleosomes have high potential to preserve bioactive compounds. [ABSTRACT FROM AUTHOR]

Abstract: Three natural oil body emulsions of a similar fat content (∼5%), but differing in their protein composition were obtained from an aqueous maize germ extract. The first was prepared by concentrating the aqueous oil body extract with ultrafiltration to a fat content of ∼5%. The other two were prepared by initially recovering the oil bodies from the extract by centrifugation, either in the presence of sucrose or by applying isoelectric precipitation at pH 5.0 and then diluting the resulting oil body creams with deionized water. The oxidative and physical stability of the three emulsions, either as they were or after submission to thermal treatment (100°C for 15min), were studied following storage at 45°C. The emulsions differed both in their oxidative and physical stability, depending on the recovery method that in turn influenced their continuous phase and/or interfacial membrane protein and/or polar antioxidant composition. Ultrafiltration resulted in the most stable emulsion. Mixtures of the natural oil body emulsions with green tea extracts, aiming to serve as a base for functional beverages, were then prepared and studied for their creaming behaviour. The green tea polyphenols seem to interact with the oil bodies leading to intensive dispersion destabilisation which, however, was halted following carrageenan addition at a relatively very low level. [Copyright &y& Elsevier]

Abstract: Storage triacylglycerols in oleaginous seeds are surrounded by a layer that consists of phospholipids and proteins, mainly oleosins. These entities are intracellular organelles, known as oil bodies. It is often reported that they have a spherical shape, but imaging using cryo-SEM analysis showed that they are rather elastic and their shape depends on their surrounding environment. In this research we have shown that in maize germ, which has a relatively low moisture content, the oil body geometry depends on the available space they have. On the other hand, oil bodies in sunflower seeds, which contain double amounts of water, appear with an almost spherical shape. Oil bodies can be extracted from oleaginous seeds using an aqueous alkaline extraction, which leads to a stable natural oil-in-water emulsion. As no additional energy is required, this method can be considered as sustainable and may find a lot of potential uses in industry. Extraneous co-extracted proteins most likely form a second layer around the oil body surface, which protects the oil bodies from coalescence, even at high oil concentration. The extraneous proteins of maize germ oil body emulsions could be removed by applying aqueous washing steps, but not in the case of sunflower seed oil bodies. [Copyright &y& Elsevier]

Abstract: Oil bodies in the form of a naturally emulsified emulsion were recovered from maize germ by applying aqueous extraction and were then exploited in the preparation of composite sodium caseinate-based films. Following equilibration of the initial film-forming dispersion, the caseinate molecules appeared to adsorb to the oil droplet surface facilitating thus the dispersion of the latter in the protein solution. During the course of film formation partial destabilization of oil body dispersion took place as a result of depletion by non-adsorbed caseinate. The finally formed composite films differed from the control, both in their surface characteristics as well in physicochemical and tensile properties. The oil-incorporating films were less transparent, less hydrophilic and, as a result, more resistant to water sorption and vapor permeation than the oil-free caseinate films. In addition, the composite films exhibited higher flexibility and lower stiffness. These findings are discussed in terms of the formation during the drying step of a composite caseinate-based phase separated structure embedded with oil bodies having their surface in intimate association with the protein molecules of the continuous protein matrix. [Copyright &y& Elsevier]

Abstract: Two oil body creams, differing in oil volume fraction and surface protein composition, were obtained by applying alkaline aqueous extraction to comminuted maize germ and then recovering the oil bodies from the extract by centrifugation, either in the presence of 0.5M sucrose (OB-W) or following isoelectric precipitation at pH 5.0 (OB-A). Oil bodies in the former cream are stabilised by natural oil body surface proteins while in the OB-A cream, exogenous proteins, in addition to natural oil body proteins, are also present. The creams were blended with appropriate amounts of water, NaCl and liquid yolk, and the pH was adjusted to 3.8 to obtain 20% or 45% (w/w) in oil OB-W and 20% (w/w) in oil OB-A model dressing-type emulsions. The physical stability of the emulsions, against creaming and coalescence, was monitored upon storage, while the development of emulsion structure during ageing was probed by applying steady shear and small deformation oscillatory rheometry. The adsorbed to oil bodies’ surface proteins were analysed by applying SDS–PAGE. Since no yolk protein constituents were detected at the oil body surface layer of the emulsions, it is hypothesised that the presence of unadsorbed yolk particles in the emulsion continuous phase results in the intensification of interdroplet interaction effects, due to depletion events, and may therefore have an indirect but nevertheless strong influence on emulsion structure and physical stability. [Copyright &y& Elsevier]

Abstract: The viscoelastic characteristics of a purified oil body cream (67.6±0.7% lipid, 5.4±0.7% protein and 25.2±0.1% moisture) recovered from sunflower seeds (Helianthus annuus L.) have been determined. Moreover, the effects of pH (2–7) and CaCl2 concentration (0–150mM) on rheology and physical stability of oil body emulsions have been studied. Oscillatory measurements showed that the purified oil body cream exhibited weak gel-like behaviour. Diluted oil body emulsions (⩽20wt% oil) showed extensive creaming (creaming index=56–59%) at pH 5–6 resulting in significant (P<0.05) increases in perceived droplet size (D(3,2)=11–13μm compared with 0.3μm at pH 7) and viscosity (0.025–0.035Pas at shear rate 10s−1 compared with 0.008Pas at pH 7). Microscopic examination revealed that the emulsion droplets aggregated at pH 5–6 but did not coalesce. The influence of CaCl2 was investigated at pH above (pH 7) and below (pH 3) the isoelectric point (IEP) of the intrinsic oleosin proteins (pH 5⩽IEP⩽pH 6) associated with the surface of the oil bodies. At pH 7, oil bodies were stable up to a CaCl2 concentration of 1.5mM; at 5–150mM CaCl2 creaming occurred (66–70%), and significant (P<0.05) increases in perceived droplet size (D(3,2)=10–13μm) and viscosity (0.015Pas at shear rate 10s−1) were observed. At pH 3 there was no significant (P>0.05) influence of CaCl2 on emulsion stability or rheology. These findings demonstrate that rheology and stability of oil body emulsions are, like processed emulsions, affected by pH and by ionic concentration when the pH is above the IEP of the surface components of the oil body. The novelty in this work therefore lies in the source of the emulsion, a natural, pre-formed oil-in-water emulsion derived from seed tissue. [Copyright &y& Elsevier]

Abstract: Oleosins stabilize oil bodies in seeds and other tissues and contain a unique hydrophobic domain which appears to be inserted into the oil matrix as an α-helical hairpin. The oleosin proteins may be exploited to stabilize emulsions while the ease of oil body preparation has led to the expression of bioactive proteins as oleosin fusions in molecular farming. [Copyright &y& Elsevier]

Two soybean oil body (SOB) creams were recovered from soybean at pH 7 and pH 11, respectively, and dispersed in water to obtain a natural 5% o/w emulsion. The lipoxygenase (LOX) activity and oleosin hydrolysis behavior in two SOB emulsions, as affected by different washing times and thermal treatments (50–110 °C), were investigated. The SOB emulsions recovered under neutral conditions (pH 7) were accompanied by strong enzymatic degradation. The absence of LOX and oleosin hydrolase activities was observed in SOB emulsions recovered under alkaline conditions (pH 11). The oxidative and physical stabilities of two SOB emulsions were examined at 37 °C under 15-day storage. Thermal treatment significantly enhanced the oxidative stability of two SOB emulsions due to enzymatic inactivation or altered interfacial properties. Both SOB emulsions exhibited excellent coalescence resistance after the elimination of enzymatic degradation, but their oxidative stability was different. It was due to the modification of the SOB surface by exogenous proteins that accelerated its oxidation. The results of this study might help design highly stable products based on SOB to meet the demand of people for natural products. • Recovery of SOB at neutral pH was accompanied by intense enzymatic degradation. • The integrity of SOB unaffected by thermal treatment and alkaline recovery processes. • SOB emulsions without enzymatic degradation exhibited good oxidative stability and resistance to coalescence. • Modification of the SOB surface by exogenous proteins accelerated SOB oxidation in the absence of enzymatic activity. [ABSTRACT FROM AUTHOR]

• Oil bodies from Brassica napus seeds were assessed for hydrolytic activity. • Carry-over of oil body hydrolytic activity is affected by the recovery medium used. • Most of hydrolytic activity is reduced with a short-time thermal treatment (95 °C). • The integrity of oil bodies is not affected by the thermal treatment applied. • Reducing hydrolytic activity enhances the physical stability over storage. The lipolytic activity in oil body creams as affected by recovery and washing protocols was investigated. The effect of thermal treatment on the hydrolytic activity and physical stability of fresh and aged (up to 30 days) oil body emulsions was studied. The use of alkaline pH solutions (9.5) to soak and grind rapeseeds were more effective reducing the contamination of oil body material from seed proteins/enzymes, compared with neutral pHs. Soaking and grinding seeds with a NaHCO 3 solution (0.1 M, pH 9.5) yielded oil bodies with a similar composition to those prepared in urea (9 M); however, the physical stability over storage was compromised due to the presence of hydrolytic enzymes. Heating a dispersion of oil bodies for 6 mins at 95 °C did not alter the physical properties of oil bodies and significantly reduced lipolytic activity (>90% enzyme inactivation), resulting in a stable emulsion. [ABSTRACT FROM AUTHOR]

Consumers are increasingly interested in decreasing their dietary intake of animal-based food products, due to health, sustainability, and ethical concerns. For this reason, the food industry is creating new products from plant-based ingredients that simulate many of the physicochemical and sensory attributes associated with animal-derived foods, including milk, eggs, and meat. An understanding of how the ingredient type, amount, and organization influence the desirable physicochemical, sensory, and nutritional attributes of these plant-based foods is required to achieve this goal. A potential problem with plant-based diets is that they lack key micronutrients, such as vitamin B12, vitamin D, calcium, and ω-3 fatty acids. The aim of this review is to present the science behind the creation of next-generation nutritionally fortified plant-based milk substitutes. These milk-like products may be formed by mechanically breaking down certain plant materials (including nuts, seeds, and legumes) to produce a dispersion of oil bodies and other colloidal matter in water, or by forming oil-in-water emulsions by homogenizing plant-based oils and emulsifiers with water. A brief overview of the formulation and fabrication of plant-based milks is given. The relationship between the optical properties, rheology, and stability of plant-based milks and their composition and structure is then covered. Approaches to fortify these products with micronutrients that may be missing from a plant-based diet are also highlighted. In conclusion, this article highlights how the knowledge of structural design principles can be used to facilitate the creation of higher quality and more sustainable plant-based food products. [ABSTRACT FROM AUTHOR]