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Enzymatic pretreatment of seeds is a novel approach that enhances the health benefits of the extracted oil. The study investigated the influence of the enzymatic pretreatment of seeds on the quality of oil from different pomegranate cultivars. The quality of the ultrasound-assisted (and ethanol-extracted) oil was studied, with respect to the refractive index (RI), yellowness index (YI), conjugated dienes (K232), peroxide value (PV) ρ-anisidine value (AV), total oxidation value (TOTOX), total carotenoid content (TCC), total phenolic compounds (TPC), fatty acid composition, phytosterol composition, ferric reducing antioxidant power (FRAP), and 2.2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging capacity. The seeds of three different pomegranate cultivars ('Wonderful', 'Herskawitz', and 'Acco') were digested with an equal mixture of Pectinex Ultra SPL, Flavourzyme 100 L, and cellulase crude enzymes, at a concentration, pH, temperature, and time of 1.7%, 4.5, 40 °C, and 5 h, respectively. Enzymatic pretreatment of PS increased oil yield, PV, TPC, TCC, and DPPH radical scavenging capacity, but decreased the YI. The levels of K232, AV and TOTOX, fatty acids, phytosterols, RI, and FRAP, were not significantly affected by enzymatic pretreatment of PS. Principal component analysis (PCA) established that oil extracted from the 'Acco' seed after enzymatic pretreatment had higher yield, TPC, TCC, and DPPH radical scavenging capacity. Therefore, enzyme-pretreated 'Acco' pomegranate fruit seed is a source of quality seed oil with excellent antioxidant properties.

This study determined the antimicrobial and antioxidant activity of lemongrass (LO), thyme (TO), and oregano (OO) essential oils and ethanolic extracts of pomegranate peel (PPE) and grape pomace (GPE) as candidate ingredients for edible coatings. Antifungal effects against Botrytis   cinerea and Penicillium spp. were tested using paper disc and well diffusion methods. Radical scavenging activity (RSA) was evaluated using 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid assays. Gas chromatography-mass spectrometry analysis identified limonene (16.59%), α-citral (27.45%), β-citral (27.43%), thymol (33.31%), paracymene (43.26%), 1,8-cineole (17.53%), and trans-caryphellene (60.84%) as major compounds of the essential oils. From both paper disc and well diffusion methods, LO recorded the widest zone of inhibition against tested microbes ( B. cinerea and Penicillium spp.). The minimum inhibitory concentrations of LO against B. cinerea and Penicillium spp., were 15 µL/mL and 30 µL/mL, respectively. The highest (69.95%) and lowest (1.64%) RSA at 1 mg/mL were recorded for PPE and OO. Application of sodium alginate and chitosan-based coatings formulated with LO (15 or 30 µL/mL) completely inhibited spore germination and reduced the decay severity of 'Wonderful' pomegranate. Lemongrass oil proved to be a potential antifungal agent for edible coatings developed to extend shelf life of 'Wonderful' pomegranate.

This study investigated the effect of blanching pomegranate seeds (PS) on oil yield, refractive index (RI), yellowness index (YI), conjugated dienes (K232), conjugated trienes (K270), total carotenoid content (TCC), total phenolic compounds (TPC) and DPPH radical scavenging of the extracted oil. Furthermore, phytosterol and fatty acid compositions of the oil extracted under optimum blanching conditions were compared with those from the oil extracted from unblanched PS. Three different blanching temperature levels (80, 90, and 100 °C) were studied at a constant blanching time of 3 min. The blanching time was then increased to 5 min at the established optimum blanching temperature (90 °C). Blanching PS increased oil yield, K232, K270, stigmasterol, punicic acid, TPC and DPPH radical scavenging, whereas YI, β-sitosterol, palmitic acid and linoleic acid were decreased. The RI, TCC, brassicasterol, stearic acid, oleic acid and arachidic acid of the extracted oil were not significantly ( p > 0.05) affected by blanching. Blanching PS at 90 °C for 3 to 5 min was associated with oil yield, TPC and DPPH. Blanching PS at 90 °C for 3 to 5 min will not only increase oil yield but could also improve functional properties such as antioxidant activity, which are desirable in the cosmetic, pharmaceutical, nutraceutical and food industries.

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]

Purpose – The purpose of this study was to characterize fruit properties of pomegranate cultivars grown in South Africa in order to provide information to assist in selecting cultivars for food and industrial purposes, as well as to optimize postharvest handling and processing. Design/methodology/approach – The physical, textural and chemical properties as well as volatile profile and free radical scavenging capacity of eight cultivars (cvs “Acco”, “Arakta”, “Bhagwa”, “Ganesh”, “Herskawitz,” “Molla de Elche”, “Ruby”, and “Wonderful”) were quantified to demonstrate the diversity among the characters of the commercially grown cultivars. Findings – Statistically significant differences were found between cultivars for most of the evaluated characters, primarily highlighting the genetic diversity among the cultivars. The classification of fruit cultivars based on quality traits (such as size, texture, colour, soluble solids, acidity, juiciness and phenolics) showed the great potential of the cultivars for processing and fresh market. The relationship among these quality traits was analysed by principal component analysis (PCA) resulting in the separation of the investigated cultivars into two groups (cluster 1=Ruby, Arakta and Ganesh; Class 2=Bhagwa, Acco and Herskawitz) and two ungrouped cultivars (Molla de Elche and Wonderful). Specific understanding about quality traits of each cultivar was established using the correlation coefficients obtained. Originality/value – This study provides valuable fundamental information that can be useful for commercial and industrial purposes, as well as the development of optimal postharvest handling and processing parameters for the investigated South African grown pomegranate cultivars. [ABSTRACT FROM AUTHOR]

Abstract: Pomegranate fruit (Punica granatum L.) has gained commercial importance in recent years in the food and health industries due to increasing scientific evidence linking its consumption to better health outcomes. In the present study, the evolution of some chemical contents, individual organic acids and sugars, phenolic composition and antioxidant capacity of pomegranate (cv. ‘Bhagwa’) during maturation was investigated. The results showed significant (P <0.05) increases in sugar content, ascorbic acid and total anthocyanins during fruit maturation, while significant decreases occurred in titratable acidity (TA), organic acids and total phenolic contents (TPCs). The significant increase in TSS/TA ratio, which plays a significant role in juice flavor, peaked at 140 DAFB, while the highest accumulation of anthocyanin content occurred at the full-ripe stage (165 DAFB). Total antioxidant capacity (both DPPH and FRAP) declined during fruit maturation, suggesting a decrease in antioxidant power of fruit juice. Strong correlations between TPC and antioxidant capacity measured by the DPPH (r 2 =0.99) and FRAP (r 2 =0.96) methods were observed. Fructose and glucose were established to be the major sugars in the fruit cultivar while tartaric acid was the predominant organic acid. Principal component analysis (PCA) showed that harvest maturity of ‘Bhagwa’ pomegranate fruit is dependent on time from full bloom hence could be fixed around 165 DAFB, where fruits were characterized by intense fruit and aril pigmentation as well as high juice quality parameters. This information provided could help pomegranate juice producers to assess and optimize juice quality and antioxidant value of ‘Bhagwa’ pomegranate cultivar through maturity. [Copyright &y& Elsevier]

The present research studied the influence of blanching and microwave pretreatment of seeds on the quality of pomegranate seed oil (PSO) extracted by cold pressing. Pomegranate seeds (cv. Acco) were independently blanched (95 ± 2 °C/3 min) and microwave heated (261 W/102 s) before cold pressing. The quality of the extracted oil was evaluated with respect to oxidation indices, refractive index, yellowness index, total carotenoids content, total phenolic content, flavor compounds, fatty acid composition, and 2.2-diphenyl-1-picryl hydrazyl (DPPH) and 2.2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging capacity. Blanching and microwave pretreatments of seeds before pressing enhanced oil yield, total phenolic content, flavor compounds, and DPPH and ABTS radical scavenging capacity. Although the levels of oxidation indices, including the peroxide value, free fatty acids, acid value, ρ-anisidine value, and total oxidation value, also increased, and the oil quality conformed to the requirements of the Codex Alimentarius Commission (CODEX STAN 19-1981) standard for cold-pressed vegetable oils. On the other hand, blanching and microwave heating of seeds decreased the pomegranate seed oil's yellowness index, whilst the refractive index was not significantly (p > 0.05) affected. Even though both blanching and microwave pretreatment of seeds added value to the cold-pressed PSO, the oil extracted from blanched seeds exhibited lower oxidation indices. Regarding fatty acids, microwave pretreatment of seeds before cold pressing significantly increased palmitic acid, oleic acid, and linoleic acid, whilst it decreased the level of punicic acid. On the contrary, blanching of seeds did not significantly affect the fatty acid composition of PSO, indicating that the nutritional quality of the oil was not significantly affected. Therefore, blanching of seeds is an appropriate and valuable step that could be incorporated into the mechanical processing of PSO. [ABSTRACT FROM AUTHOR]

Seed oil blending is a novel approach that may enhance the oil antioxidant capacity. The study evaluated the effect of blending sunflower oil (SO) with pomegranate seed oil (BPSO) from blanched seeds (95 °C/ 3 min) on oxidative stability and antioxidant properties of the oil blends. SO and pomegranate seed oil from unblanched seeds (PSO) were used as controls. Blending SO with BPSO and PSO was assessed in the following respective proportions: 90:10, 85:15, and 80:20 (w/w) with respect to total phenolic content, total carotenoids content, tocopherols content, and fatty acid composition to establish the best blending ratio. An accelerated storage test was conducted using the best blending ratio (85:15) at 60 ± 2 °C for 20 days. The evolution of peroxide value, ρ-anisidine value and, total oxidation value, together with the depletion of the oils' 2.2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2.2-diphenyl-1-picryl hydrazyl (DPPH) and radicals scavenging capacity were evaluated. Volatile oxidation compounds (VOCs) were assessed at the end of the accelerated storage test. Blended oils exhibited better oxidative stability than SO. Nevertheless, the oxidative stability of SO:PSO and SO:BPSO blends did not significantly vary. Additionally, blended oils showed a lower rate of DPPH and ABTS radical scavenging capacity depletion than SO, although this did not significantly vary between the oil blends. The concentration of VOCs was significantly higher in SO than blended oils. No significant difference in the content of VOCs was observed between SO:PSO and SO:BPSO blends. The findings of this study are valuable to the food industry, which is presently interested in nonconventional oils and functional foods to improve health and human nutrition. [ABSTRACT FROM AUTHOR]

Blanch-assisted hot-air drying of pomegranate arils with blanching treatments 90 °C for 30 s, 100 °C for 60 s, and unblanched (control) arils were investigated. Effects of blanching on enzyme inactivation (polyphenol oxidase and peroxidse), colour, texture, and other qualities of dried arils were discussed. The hot-air drying conditions were 60 °C, 19.6% relative humidity, and 1.0 m s−1 air velocity. Results showed that blanching reduced enzyme activity by 76% and 68% for blanched arils treated at 90 °C for 30 s and 100 °C for 60 s, respectively, compared to unblanched arils. With regard to the total colour difference (TCD), unblanched arils were 20.9% and 16.6% higher than blanched arils treated at 90 °C for 30 s and 100 °C for 60 s, respectively. Furthermore, the total soluble solids (TSS) for unblanched aril increased significantly from 16.1 to 24.9 °Brix after drying, followed by arils treated at 90 °C for 30 s and 100 °C for 60 s (21.4; 18.5 °Brix), respectively. Among the blanching treatments, dried arils treated at 90 °C for 30 s had the highest total anthocyanin content (28.6 mg C3gE/g DM), followed by 100 °C for 60 s (24.8 mg C3gE/g DM). Similarly, dried arils treated at 90 °C for 30 s had the highest radical scavenging activity (RSA) (32.1 mM TE/g DM) while the least was observed with unblanched arils (17.0 mM TE/g DM). Overall, the blanching treatment was more effective to maintain the quality attributes of pomegranate dried arils. [ABSTRACT FROM AUTHOR]

Rind biochemical concentrations and radical-scavenging activities of ‘Nules Clementine’ mandarin could play a significant role in the susceptibility of the fruit to various forms of physiological rind disorders. This study examined the effect of fruit position within tree canopy on biochemical concentrations and radical-scavenging activities of ‘Nules Clementine’ mandarin fruit rind after harvest at week 0 and after 3, 6 and 9 weeks of postharvest cold storage at 7.5 ± 0.5 °C. Biochemical concentrations and radical-scavenging activities of flavedo and albedo tissues of the rind were also examined. Fruit from inside canopy (IC) and outside canopy (OC) were harvested at commercial maturity in May 2015 and 2016 from Unifruiti and Swartvelei Farms located at Eastern Cape (EC) (33° 27′ 32″ S, 25° 34′ 79″ E) and Western Cape (WC) (19° 02′ 33.8″ S, 33° 41′ 17.24″ E) provinces of South Africa, respectively. Results showed that canopy position played a significant ( p < 0.001) role on total carotenoids, total phenolics and total flavonoids as well as rind dry matter, with OC fruit often characterised by higher biochemical concentrations than IC fruit during cold storage. The study further showed that production region influenced radical-scavenging activities and carbohydrate content of OC and IC fruit rind during cold storage. Radical-scavenging activities of OC fruit (61.2%) were higher than IC fruit (52.5%) from EC whereas radical-scavenging activities of IC fruit (67.1%) were higher than those of OC fruit (58.2%) from WC at harvest. Overall, this study revealed that fruit position within tree canopy influenced its rind biochemical concentrations and radical-scavenging activities. [ABSTRACT FROM AUTHOR]

Abstract Rind biochemical properties play major roles in defence mechanisms against the incidence of rind physiological disorders of citrus fruit during cold storage. Hence, multivariate calibration models were developed to rapidly and non-destructively determine rind biochemical properties of citrus fruit from visible to near-infrared (Vis/NIR) spectra acquired by Vis/NIR spectroscopy using partial least square regression algorithm. To achieve optimum models for determination of each rind biochemical property, several mathematical pre-processing methods were explored, including no pre-treatment. However, special emphases were given to the best model statistics in terms of coefficient of determination (R2) and residual predictive deviation (RPD). Models were performed by critical examination of different wavelength ranges (visible, near-infrared and full regions) and combinations of fruit harvested from different production regions and acquired before (week 0) and after (week 9) cold storage. Results obtained showed excellent models for determining parameters such as sucrose (R2 = 0.99 and RPD = 11.42), total flavonoids (R2 = 0.99 and RPD = 12.37), and chlorophyll b (R2 = 0.97 and RPD = 5.67). This study reported the first application of Vis/NIR and chemometrics in determining the rind biochemical properties of 'Marsh' grapefruit rapidly and non-destructively. [ABSTRACT FROM AUTHOR]