Influence of soaking time on the mechanical properties of rapeseed and their effect on oleosome extraction

Efficiency of aqueous oleosome extraction from capsicum seeds compared to classical oil extraction

The extraction of oil from oilseeds in intact oleosomes is one of the suggested processes that could replace the extraction of oil by pressing and solvent extraction, being milder, environmentally less impactful and potentially more efficient in its use of resources. This study assesses the latter using an exergy assessment of oleosome extraction for food emulsions. The contribution of each part of the process to the overall impact was investigated. Based on current lab-scale data, oleosome extraction has nearly twice the exergy loss compared to the industrial process of oil extraction and industrial assembly of emulsions. The exergy losses of the lab-scale oleosome extraction are currently dominated by the chemical exergy associated with product loss during the separation of oleosomes from the rest of the biomass. This loss is expected to significantly decrease when upscaled to industrial scale. When substituted with industrial material efficiencies, the total exergy loss decreased to nearly a quarter of the original loss, representing oleosome extraction as a potentially more effective and environment-friendly option.

Pectin polysaccharide contribution to oleosome extraction after wet milling of rapeseed

Oleosomes are lipid composites providing energy storage in oilseeds. They possess a unique structure, comprised of a triglyceride core stabilized by a phospholipid-protein membrane, and they have shown potential to be used as ingredients in several food applications. Intact oleosomes are extracted by an aqueous process which includes soaking, milling, and gravitational separation. However, the details of the complexes formed between oleosomes, proteins and pectin polysaccharides during this extraction are not known. It was hypothesized that pectins play an important role during the oleosome separation, and different proteins will be complexed on the surface of the oleosomes, depending on the pH of extraction. Rapeseed extracts were treated with and without pectinase (Pectinex Ultra SP-L) and extracted at pH 5.7 or 8.5, as this will affect electrostatic complexation. Acidic conditions led to co-extraction of storage proteins, structured as dense oleosome emulsions, stabilized by a network of proteins and polysaccharides. Pectinase intensified this effect, highlighting pectic polysaccharides' role in bridging interactions among proteins and oleosomes under acidic conditions. The presence of this dense interstitial layer around the oleosomes protected them from coalescence during extraction. Conversely, under alkaline conditions, the extraction process yielded more purified oleosomes characterized by a larger particle size, most likely due to coalescence. Nevertheless, pectinase addition at pH 8.5 mitigated coalescence tendencies. These results contribute to a better understanding of the details of the colloidal complexes formed during extraction and can be used to modulate the composition of the extracted fractions, with significant consequences not only for yields and purity but also for the functional properties of the ingredients produced.

Plant oil bodies and their membrane components: new natural materials for food applications

Plants store triacylglycerols in the form of oil bodies (OBs) as an energy source for germination and subsequent seedling growth. The interfacial biomaterials from these OBs are called OB membrane materials (OBMMs) and have several applications in foods, e.g., as emulsifiers. OBMMs are preferred, compared with their synthetic counterparts, in food applications as emulsifiers because they are natural, i.e., suitable for clean label, and may stabilize bioactive components during storage. This review focuses mainly on the extraction technologies for plant OBMMs, the functionality of these materials, and the interaction of OB membranes with other food components. Different sources of OBs are evaluated and the challenges during the extraction and use of these OBMMs for food applications are addressed.

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

Reports concerning the characteristics of soybean oil bodies (SOBs) isolated from high protein genotypes and high oil genotypes of soybeans available in the literature are insufficient and limiting. In this study, fatty acid compositions, total phenol and tocopherol contents, antioxidant capacity, and physicochemical stability of SOB emulsions recovered from three high-protein and three high-oil genotype soybeans were comparatively investigated. Principal component analysis showed that all six SOB samples could be easily discriminated based on the cultivar characteristics. Overall, the SOBs derived from the high-protein soybeans exhibited higher polyunsaturated fatty acid (PUFA) contents, while the SOBs derived from the high-oil soybeans had higher extraction yields and tocopherol contents; the tocopherol content was also positively correlated with the antioxidant capacity of the lipophilic fraction, but the difference in the total phenolic content between the two genotypes was not significant. The SOBs derived from the high-protein soybeans were more easily oxidized during storage, with 1.38- and 4-fold higher accumulation rates of lipid hydroperoxides (LPO) and thiobarbituric acid reactive substances (TBARS), respectively, in the high-protein-derived SOBs than in the high-oil-derived SOBs. In addition, the SOBs from the high-protein soybeans exhibited pronounced coalescence during storage, which was corroborated by focused confocal microscopy. These results confirmed that SOBs obtained from high-oil soybean genotypes are more suitable to manufacture OB-based products due to their superior physicochemical stability.

Synergistic effect of microwave heating and hydrothermal treatment on cyanogenic glycosides and bioactive compounds of plum (Prunus domestica L.) kernels: An analytical approach

The effects of microwave heating (450 W for 6 min), hydrothermal treatment (6, 9, and 12 h at 45 °C) and their combination on compositional characteristics, cyanogenic glycosides, color, and bioactive compounds of plum kernels have been studied. The conditions examined caused a significant reduction of 37.81, 72.17, 84.41, 91.24 and 98.02% in cyanogenic glycosides of differently treated plum kernels. Total phenolic and total flavonoid compounds of plum kernels showed hydrothermal time-dependent duration decline. The larger shifts in FT-IR spectra near 1157 cm-¹ provided valuable insights on the reduction of cyanogenic glycosides during combined treatments. The variation of color attributes (L*, a*, b*), during combined treatments indicates a more reddish tonality of plum kernel samples. The combined effect of hydrothermal (12 h at 45 °C) and microwave heating (450 W for 6 min) proved to be an effective tool for neutralizing the toxic effect of cyanogenic glycosides, opening up possibilities for its use in food industries.

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Hydrothermal and microwave treatments were applied to detoxify plum kernels.

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The treatments caused highest reduction of 98.02% in cyanogenic glycosides.

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Combined treatments neutralized the toxic effect of cyanogenic glycosides.

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FT-IR spectra provided valuable insights on the reduction of cyanogenic glycosides.