Effect of Microwave Pretreatment of Seeds on the Quality and Antioxidant Capacity of Pomegranate Seed Oil

Oven-Roasting Effects the Fatty Acid Composition, Antioxidant Properties, and Oxidative Stability of Pomegranate (Punica granatum L.) Seed Oil

In this study, we investigated the effect of roasting conditions and time on the physicochemical properties of pomegranate seed oil. We analyzed the fatty acid, total phenolic, flavonoid, tocopherol, and phytosterol contents of pomegranate seed oil extracted under four conditions: raw, heated at 160°C for 15 min, heated at 160°C for 20 min, and heated at 180°C for 10 min, which included three that were well-established to enhance nutritional and flavor properties. Furthermore, the oxidative stability was evaluated based on the acid value, peroxide value, and induction period. Roasting significantly decreased the contents of punicic acid, polyunsaturated fatty acids, tocopherol, and phytosterol and the 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity (P<0.05) of the oil. Conversely, saturated fatty acids, monounsaturated fatty acids, acid value, peroxide value, total phenolic and flavonoid contents, and induction period were significantly increased (P<0.05). Our results suggest that the roasting conditions were nutritionally and oxidatively stable, thereby enhancing the roasting process and providing a database for essential roasting treatments for pomegranate seed oil.

Thermal processing of pomegranate seed oils underscores their antioxidant stability and nutritional value: Comparison of pomegranate seed oil with sesame seed oil

In the present study, the oxidative stability and antioxidant activity of seed oils were investigated in three Iranian pomegranate cultivars, Shirin Khafr, Torsh Sabz, and Rabab, along with the sesame (Sesamum indicume L. cv Dezful) seed oil. Punicic acid was the primary fatty acid in the pomegranate seed oils, with contents ranging from 75.5 to 80.9% (w/w). The tocopherol levels in pomegranate seed oils ranged from 1439 to 2053 mg/kg, whereas the phenolics ranged from 130 to 199.3 mg/kg, respectively. Comparatively, in the seed oil of sesame "Dezful," these substances' contents were 1053 and 79 mg/kg, respectively. Contrary to common perception, the seed oil of the three pomegranate cultivars cultivated in Iran had high oxidative stability and antioxidative activity during the 32 h of thermal processing at 170°C. The oxidation stability assayed by peroxide value, p-anisidine value, and TOTOX index revealed that the pomegranate seed oils had a much higher resistance to the oxidation process than the sesame oil. The content of tocopherols increased during thermal processing due to the regeneration phenomenon. Tocopherols are not always free and may form a matrix with themselves or other compounds. Changes in the antioxidant activity during the thermal processing assessed by DPPH free radical scavenging power and by the FRAP test were consistent with those for the antioxidants. Therefore, these oils can be added to other edible oils as a natural antioxidant to improve their oxidative stability.

New perspectives on different Sacha inchi seed oil extractions and its applications in the food and cosmetic industries

Sacha inchi oil is growing in demand worldwide owing to its high fatty acid content of linolenic acid (44.30%-51.62%) and linoleic acid (34.08%-36.13%). In addition, Sacha inchi oil also contains phytosterols, such as stigmasterols (346- 456 μg/g), sitosterols (435-563 μg/g), and campesterols (10.47% ± 4.36%). Its main tocopherol is gamma-tocopherol (120.41-125.69 mg/100 g). The antinutrients in Sacha inchi seeds can be reduced by roasting prior to extraction. Various extractions, including both conventional and novel methods, have been used to extract Sacha inchi oil. However, the variety of extraction methods and origins of the seeds change the nutrient profiles, antinutrient content, and physicochemical properties. Incorporation of Sacha inchi oil into food products can increase its nutritional value, and it works as a moisturizing agent in cosmetic products. To obtain Sacha inchi oil with the desired properties and nutritional profile, this review summarizes the effects of different Sacha inchi seed oil extraction methods and processes on chemical compounds, antinutrient content, and physicochemical properties, including their potential and recent applications in food and cosmetic industries.

Influence of microwave heating on bioactive properties, phenolic compounds and fatty acid profiles of pomegranate seed oil

In this study, the effects of different microwave powers on the bioactive properties, fatty acid and phenolic profiles of pomegranate seed oil were reported using various analytical methods, GC and HPLC. Antioxidant capacity and total phenolic values of pomegranate seed oils were established between 14.16% (control) and 19.18% (720 and 900 W) to 0.00 (900 W) and 3.61 mgGAE/100 g (control), respectively. The viscosity values of pomegranate seed oil increased with the heat treatment. But, the viscosity of the oils increased with the applied Watt increase. The p-coumaric acid amounts of the seed oils heated at 180, 720 and 900 W in the microwave were found to be statistically similar. In general, phenolic compounds of pomegranate seed oils did not show a constant increase or decrease depending on microwave power. The key fatty acid of pomegranate seed oil was punisic acid (30.49-36.10%). followed by linoleic acid (25.95-30.01%).

Effect of gum Arabic and ethanol pretreatments on drying kinetics and quality attributes of dried carrot slices

Carrot is an important root vegetable to the food industry and consumers due to its nutritional and health benefits. Given the high moisture content and low shelf life of fresh carrots, preserving this highly demanded vegetable is vital. This current research modelled the drying kinetics and evaluated the quality of ultrasonic-assisted gum Arabic and ethanol pretreated and oven-dried carrot slices. Fresh carrots were processed into thin slices and immersed in 3% gum Arabic (GA), ethanol (99.9%), and distilled water (control), followed by ultrasonication (frequency: 50 Hz, power: 500 W, temperature: 25 °C) for 10 min and drying in a hot air oven at 50 °C. The loss of moisture from the carrots was periodically recorded, converted to moisture ratio before fitted to eleven semi-theoretical thin layer drying mathematical models. The effects of the pretreatments on the retention of bioactive compounds and carrots' physical and chemical properties were also evaluated. From the tested models, the Diffusion, Modified Henderson and Pabis, and Two-term models showed the best fitting (R² = 0.9944-0.9985; RSME = 0.0103-0.0227) to the experimental data from 3% GA and ethanol pretreated carrots, while control samples followed the Aghbasho model (R² = 0.9999; RMSE = 0.0033). Overall, the 3% GA pretreated carrot slices exhibited better colour (yellowness: 25.82-34.50; total colour differences: 8.12-13.06), water activity (0.37-0.44), total phenolic content (1.34-2.99 mg GAE/100 g DM), β-carotene (7.63-13.07 mg/100 g DM), and DPPH radical scavenging activity (5.67-8.02 mM AAE/100 g DM) than ethanol pretreated carrot slices and control samples. At the same time, 3 % GA pretreatment did not affect the drying rate of the carrot slices. The total soluble solids/titratable acidity ratio, rehydration capacity, and shrinkage ratio did not significantly (p > 0.05) vary among the treatments. The findings of this study can be used to develop an optimal drying protocol for pretreated carrot slices and to produce shelf-stable carrot products that can be used dried, rehydrated, or in combination with other products.

Optimization of smashing tissue and ultrasonic extraction of tanshinones and their neuroprotective effect on cerebral ischemia/reperfusion injury by inhibiting parthanatos

A green smashing tissue and ultrasonic (STU) extraction method, which combines smashing tissue and ultrasonic-assisted extraction, was developed for the first time. The extraction of tanshinones from Salvia miltiorrhiza Bunge (SM) was taken as an example to discuss the practicability of this method. Taking the total yield of eight tanshinones as an evaluation index, response surface methodology (RSM) and artificial neural network (ANN) models were used to optimize the extraction parameters, and these two models were also compared by investigating the extract yield of tanshinones and the antioxidant activity of the obtained SM extract. The optimal STU conditions by ANN were as follows: an ethanol concentration of 73%, a liquid/solid ratio of 30 mL g^-1, a smashing tissue time of 97 s and an ultrasonic time of 40 min. Under these optimal conditions, the yield of the eight components was 0.30% ± 0.12, which was greater than 0.28% ± 0.03 optimized by RSM. The IC₅₀ values of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) of the obtained extract were 55.25 ± 3.72 μg mL^-1 and 67.33 ± 2.62 μg mL^-1, respectively, which were better than those of 75.49 ± 4.33 μg mL^-1 and 112.10 ± 5.98 μg mL^-1, respectively, optimized by RSM. Furthermore, the SM extract was found to exert neuroprotective effects by inhibiting parthanatos in middle cerebral artery occlusion/reperfusion (MCAO/R)-induced rats. The results supported the use of the SM extract, which was obtained by STU, as a potential product in the cosmetics, medicine, and food industries.

Natural Antioxidants: Innovative Extraction and Application in Foods

Research has devoted great attention to the study of the biological properties of plants, animal products, microorganisms, marine species, and fungi, among others, often driven by the need to discover new medicines [...].

Quality and Antioxidant Properties of Cold-Pressed Oil from Blanched and Microwave-Pretreated Pomegranate Seed

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.