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This study has produced comparative findings on the quality (flavonoid and phenolic concentrations, antioxidant activity, and free fatty acids) and shelf‐life of garlic (Allium sativum L.) oil. Commercial (two different brands) and homemade products were used. The shelf life of the products was determined by Rancimat tests performed at 110, 120, 130, and 140°C. Principal component analysis has been employed to establish a relationship between the quality measurements. To appraise the structure of the lipid oxidation in the oil samples, thermodynamic and kinetic parameters have also been derived depending on the induction times obtained at different temperature values. One of the commercial oils has showed the longest shelf life (131 days), while the shelf life of the homemade one has been calculated as 111 days. The commercial‐2 garlic oil displayed the highest Gibbs free energy. Novelty impact statement: The quality of garlic oils was measured regarding TPC, TFA, antioxidant capacity, free fatty acid value, and shelf life.A statistical technique employing PCA was used to compare two commercial and one handmade garlic oils.This research served to determine the storage stability of homemade garlic‐infused olive oil and garlic‐infused canola oil that can be used as herbal supplements. [ABSTRACT FROM AUTHOR]

This study aimed to develop, evaluate, and compare the performance of artificial neural networks and multiple linear regression models in the estimation of phenolic profile of sunflower oil enriched by lemon balm. Total phenolic material in addition to the quality parameters (induction time and antioxidant activity) of the treated oil was compared to those of the pure sunflower oil. The oxidative stability of the product was increased by almost 7% in terms of induction time, while the phenolic profile was increased by almost 2.5 times. Moreover, the antioxidant activity of sunflower oil was enhanced by ~5 times over the pure oil. The values of artificial neural networks and multiple linear regression were calculated as: error rates 0.01% and 8.09%; root‐mean‐square error values 0.45, and 4.36; R2 values 0.9958 and 0.6183, respectively. Practical applications: Although sunflower oil is one of the most consumed food products worldwide, its susceptibility to deterioration due to its low oxidative stability is major obstacle in the related industry. Therefore, it becomes inevitable to develop the product as a functional food both in order to improve the product in terms of health, and to prevent undesirable situations by extending its shelf life. [ABSTRACT FROM AUTHOR]

Mass transfer mechanism, kinetic behavior, and thermodynamics analysis during the microwave‐assisted extraction of total polyphenols from Feijoa sellowiana peels have been investigated with aqueous ethanol (60%, v/v) under several temperature values (295, 298, 301, and 304 K). Diffusion coefficient (1.446 × 10–10, 2.576 × 10–10, 2.320 × 10–10, and 5.653 × 10–10 m2 s−1), mass transfer coefficient (0.2335, 0.3520, 0.3555, and 0.9724), and Biot number (690.23 × 103, 584.16 × 103, 655.00 × 103, and 735.36 × 103) increased by temperature. Pseudo‐wfirst‐order kinetic model described the kinetic data better over the pseudo‐second‐order kinetic model. Activation energy (106.30 kJ mol−1) calculated for the current system denotes an extraction process controlled by the reaction, rather than diffusion. Thermodynamics terms such as enthalpy (12.87 kJ mol−1), entropy (0.068 kJ mol−1K−1), and Gibbs free energy changes (−7.187, −7.390, −7.595, and −7.799 kJ mol−1) have been also evaluated to comprehend the nature (an endothermic and spontaneous process leading to more irregularity) of the extraction system. Practical applications: Comprehension of mass transfer mechanism and kinetic behavior during the solid–liquid extraction by application of microwave irradiation would let the estimation of process conditions for industrial fulfillments. Additionally, evaluation of the thermodynamic parameters would provide information on the nature of the microwave‐assisted extraction of polyphenols from Feijoa sellowiana peels. [ABSTRACT FROM AUTHOR]

Automatic solvent extraction (ASE) was employed to acquire orange peel extract rich in carotenoid by means of several solvents (hexane, heptane, and chloroform). D‐optimal design was used for the design of experiments, modeling the experimental data, and optimization of the extraction process. Selected process parameters (extraction time, particle size of the peel, and solvent type) for the current ASE system were found statistically significant at p <.0001. The highest effect was achieved by particle size, followed by extraction time and solvent. The maximum β‐carotene yield (86.85 mg per g fresh peel) was reached by 1.53 mm particle diameter peel material with heptane for ~46 min of ASE time. Then, carotenoid‐rich extract was applied as a natural food additive to increase the oxidative stability of the sunflower oil by increasing the induction time more than twice. Practical applications: Considering the fact that more than 50% of the orange fruit includes peel with respect to weight, valorization of this waste by‐product should be evaluated in terms of "zero waste economy." Finally, carotene extract produced under optimum conditions has also been studied for a practical food application. Sunflower oil was chosen as the model food product, since the concerned food is the most consumed product, which has a relatively short shelf life for the producers and consumers. The aim of this last step was to evaluate this smart additive in oil. In this way, it will be possible to prevent synthetic applications. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this research was to study the effect of microwave drying (MD) on the major phenolic compound oleuropein, total phenolic and flavonoid contents, and antioxidant activity of the olive leaves. The results were compared to those obtained after using freeze drying (FD), vacuum drying (VD), oven drying (OD), and ambient air‐drying (AAD). Response surface methodology, using a central composite face‐centerd design, was used to optimize the effects of microwave irradiation power (300–500 W), solid mass (1.5–2.5 g), and drying time (4–6 min) on oleuropein and other olive leaves antioxidant compounds. The second‐order models were found highly adequate with very low root mean squared deviation (RMSD) and high coeffecient of determination (R2) values. The results of MD under optimum conditions (2.085 g sample at 459.257 W for 6 min of drying period) has demonstrated to be the best drying method followed by FD, VD, OD, and AAD. Practical applications: Olive leaves are agricultural waste which contains significant amounts of valuable compounds such as oleuropein and phenolic compounds. Nowadays, application of these compounds has attracted considerable interest as food additives and/or nutraceuticals in both food and pharmaceutical industries. Several methods have been applied for the extraction of phenolic compounds from olive leaves and by‐products. However, to obtain higher extraction yield, it is important to reduce the water content of the samples before extraction. This study demonstrates the feasibility of using microwave drying as a promising technique compared to other methods (e.g., freeze‐, vacuum‐, oven‐, and ambient air‐drying) for drying of olive leaves with minimum changes in total phenolic, flavonoids, antioxidant activity, and oleuropein contents. [ABSTRACT FROM AUTHOR]