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Seed oil quality is a function of several attributes which include its bioactive compounds, physicochemical and functional properties. These quality attributes are important in seed oil processing as they determine the oil palatability, nutritional and market value. Besides the health, environmental and economic issues related to seed oil extraction using organic solvents such as hexane, other conventional seed oil extraction techniques such as supercritical fluid extraction, enzyme digestion and cold pressing are associated with low recovery of oil and bioactive compounds. Application of novel seeds pretreatments techniques such as microwaving, enzymatic digestion, pulsed electric field and ultrasonication do not only improve the oil yield and quality attributes, but also reduces seed oil extraction time, solvent and energy consumption. Higher phenolic compounds, carotenoids, tocopherols, phytosterols and antioxidant properties in oil from pretreated seeds offer health benefits related to the prevention of cancer, diabetes, obesity, inflammatory and cardiovascular diseases. Increased consumer interest in functional foods and the potential of seeds pretreatments in enhancing the extractability of bioactive compounds from plant material has increased the application of novel pretreatment techniques on diverse oilseeds. This review describes the commonly studied novel seeds pretreatment techniques and critically discusses their influence on the oil physicochemical attributes, oxidation indices, bioactive compounds and antioxidant properties. [ABSTRACT FROM AUTHOR]

This study investigated the effect of cultivar and blanching of pomegranate seeds (PS) on quality attributes of the extracted oil. The quality attributes studied included oil yield, refractive index (RI), yellowness index (YI), conjugated dienes (K232), peroxide value (PV), ρ-anisidine value (AV), total oxidation value (TOTOX), total carotenoids content (TCC), total phenolic content (TPC), fatty acid composition, phytosterol composition, ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity. Three different cultivars of PS ('Wonderful', 'Herskawitz' and 'Acco') were blanched at 95 °C for 3 min. In each experiment, unblanched PS were used as the control. Blanching of PS improved oil yield, YI and DPPH radical scavenging capacity, while it decreased TCC, FRAP and TOTOX. The effect of blanching PS varied among the individual fatty acids and phytosterols. Interestingly, blanching of PS increased punicic acid content and the ratio of unsaturated to saturated fatty acid (UFA: SFA). The K232, RI and TPC of the oil extracts were not significantly (p > 0.05) affected by blanching. TPC was strongly correlated (r = 0.876) with FRAP. Principal component analysis established that 'Wonderful' and 'Acco' oil extracts from blanched PS were associated with oil yield, YI and β-sitosterol, whereas 'Herskawitz' oil extracts from blanched PS were correlated with punicic acid, FRAP and DPPH radical scavenging capacity. In conclusion, blanching 'Wonderful' and 'Acco' PS may improve oil yield, β-sitosterol content and colour, whilst blanching 'Herskawitz' PS may enhance the antioxidant capacity of extracted oil, which is beneficial in the cosmetic, nutraceutical, pharmaceutical and food industries. [ABSTRACT FROM AUTHOR]

Some of the major processed horticultural commodities subjected to adulteration are powders, edible oils and juices. This review covers the recent application in the field of vibrational spectroscopic techniques (near and mid-infrared spectroscopy, Raman spectroscopy and hyperspectral imaging) for the determination of authenticity and adulteration in processed horticultural products with an emphasis on powders, edible oils and juices. The review highlights fundamental concepts, limitations and constraints associated with each spectroscopic technique in evaluating the authenticity and adulteration of processed horticultural products. Our findings suggest that the application of infrared spectroscopy (near and mid) is highly suitable for the assessment of powders, oils and juices, while Raman spectroscopy has shown potential in evaluating powders and edible oils. However, these spectroscopic tools still require improvement on measurement accessories and dynamic analytical methods for modern food inspection. Overall, the review of literature suggests that vibrational spectroscopy has the potential to fulfil the industrial need for quality control and authenticity assessment. [ABSTRACT FROM AUTHOR]

This study investigated the physical, biochemical and cellular microstructural changes of 'Wonderful' pomegranate fruit induced by impact bruising at cold (5 °C) and ambient (20 °C) temperature. Pomegranate fruit were bruised by dropping at various drop heights, from low (20 cm), medium (40 cm) to high (60 cm) impacts onto a rigid impact surface. Physical and biochemical changes such as colour browning, peel electrolyte leakage and polyphenol oxidase (PPO) enzyme activity of bruised and non-dropped (control) fruit peels were measured. Reaction oxygen species (ROS) of fluorescent probe 2,7-dichlorodihydrofluorescein diacetate (H2DCF-DA) treated fruit peels were measured by confocal laser-scanning microscopy. Qualitative assessment of microstructures between control and bruised tissues of pomegranate fruit peels was performed using scanning electron microscope (SEM). Micrographs of SEM showed cellular microstructural differences between control and bruised fruit tissues were visible after 4 and 48 h of drop impact. Medium and high impact-bruised fruit were characterized by higher ROS than control fruit. Bruise damage to pomegranate fruit lead to increased peel electrolyte leakage (PEL) both at cold and ambient temperatures. Bruising had more effect on increasing PPO activity than did the incubation temperature and time. Activity of PPO enzyme was higher in bruised fruit than control fruit. Browning score (BS) and the total colour difference (TCD) both indicated highest values corresponding to medium and high drop impact bruising. Pearson's correlation showed strong to moderate relationship between PEL, PPO activity, BS, TCD and ROS. Increase in fluorescent units of ROS showed a strong significant correlation (p < 0.05; r = 0.70) with BS and moderately correlated with TCD (p < 0.05; r = 0.67) and PPO activity (p < 0.05; r = 0.61). This study has confirmed that pomegranate fruit bruising induce the physical and biochemical changes in addition to underlying cellular microstructural alterations. [ABSTRACT FROM AUTHOR]