Chicken oil is prone to oxidation due to the high content of unsaturated fatty acids. The interaction of antioxidants was affected by their concentration, ratio, and reaction system. In this article, mixtures of zeaxanthin and tocopherols (α-tocopherol and γ-tocopherol) were chosen to enhance the oxidative stability of chicken oil. The antioxidation of zeaxanthin with tocopherols was analyzed using the Rancimat test, the free radical scavenging capacity and the Schaal oven test (the variation of antioxidant content, PV and shelf life prediction). The optimal concentration of zeaxanthin determined by Rancimat in chicken oil was 20 mg/kg. The binary mixtures have a strong synergistic effect in the ABTS experiment, and the clearance rate was up to 99%, but antagonistic effect in ORAC. The degree of synergism between zeaxanthin and tocopherols was determined by ratio. The interaction between zeaxanthin and α-tocopherol was synergistic, while the types of interaction between zeaxanthin and γ-tocopherol were affected by concentration. The main synergistic interaction mechanism was the regeneration of tocopherol by zeaxanthin. Synergistic combinations of zeaxanthin with α-tocopherol and γ-tocopherol played a key role in the primary oxidation stage of the lipid. The best synergistic combination was A3 (zeaxanthin+α-tocopherol: 15+50 23 mg/kg), which could extend the shelf life of chicken oil (92.46 d) to 146.93 days. This work provides a reference for zeaxanthin and tocopherol to improve the oxidative stability of animal fat.
Compound chocolates made of lauric-acid-based cocoa butter substitute (CBS) and cocoa butter (CB) often exhibit serious fat blooms caused by phase separation and polymorphic transformation of CB and CBS triacylglycerols. Herein, we found that the fat bloom of CBS-based chocolates could be completely inhibited by adding fat containing 1,3-dioleoyl-2-stearoyl-triacylglycerol (OSO) to CBS/CB blends. Unlike the CBS/CB chocolates that presented fat blooms within 3 wk under isothermal storage at 15, 20, and 25°C and 15 wk under thermal thawing storage at 15-25°C , no fat blooms appeared in the CBS/CB/OSO compound chocolates under any storage condition up to 6 months. The following key factors are involved in the addition of the OSO fats: the (1) concentration ratio of CB/OSO should be 1/1 such that CB/OSO can form molecular compound crystals and (2) total amount of CB+OSO in the CBS/CB/OSO blends should reach 20%. The solid fat content, hardness, and crystallisation rate of the CBS/CB/OSO blend-based chocolate compound were confirmed to be suitable for chocolate production.
The adsorbed film of cetyltrimethylammonium chloride (CTAC) at the tetradecane (C14) - water interface undergoes a first-order surface transition from two-dimensional liquid to solid states upon cooling. In this paper, we utilized this surface freezing transition to realize a spontaneous demulsification of Pickering emulsions stabilized by silica particles. In the temperature range above the surface freezing transition, the interfacial tension of silica laden oil-water interface was lower than CTAC adsorbed film, hence, stable Pickering emulsion was obtained by vortex mixing. However, the interfacial tension of CTAC adsorbed film decreased rapidly below the surface freezing temperature and became lower than the silica laden interface. The reversal of the interfacial tensions between silica laden and CTAC adsorbed films gave rise to Pickering emulsion demulsification by the desorption of silica particles from the oil-water interface. The exchange of silica particles and CTAC at the surface of emulsion droplets was also confirmed experimentally by using phase modulation ellipsometry at the oil-water interface.
In this paper, the kinetic stability of Pickering emulsions stabilized by spherical silica particles (100 nm in diameter) was examined in the water - 2,6-lutidine mixture. In the close vicinity of the lower critical solution temperature, Pickering emulsions were unstable due to the ultra-low liquid-liquid interfacial tension but increased their stability with increasing the temperature. In this system, the interfacial tension obeys universal scale law and can be tuned by temperature without adding any surface-active agents. Owing to this unique feature, we elucidated the relation between the interfacial tension and the stability of Pickering emulsions.
Herein we report the optimization of enzymatic hydrolysis of a mixture of capsaicinoids, capsaicin and dihydrocapsaicin obtained from chili peppers, and the utilization of the isolated fatty acids for the modification of coconut oil using enzyme catalyzed acidolysis. This work was carried out as the fatty acids that can be isolated from capsaicinoid hydrolysis have been shown to possess interesting biological properties. These biological properties could be better exploited by incorporating the fatty acids into a suitable delivery vehicle. The enzymatic hydrolysis of the mixture of capsaicin and dihydrocapsaicin was carried out using Novozym® 435 in phosphate buffer (pH 7.0) at 50℃. The enzyme catalyst could be reused in multiple cycles of the hydrolysis reaction. The desired 8-methyl-6-trans-nonenoic acid and 8-methylnonanoic acid were isolated from the hydrolysis reaction mixture using a simple extraction procedure with a 47.8% yield. This was carried out by first extracting the reaction mixture at pH 10 with ethyl acetate to remove any dissolved capsaicinoids and vanillyl amine side product. The fatty acids were isolated after adjustment of the pH of the reaction mixture to 5 and second extraction with ethyl acetate. The acidolysis of coconut oil with the obtained fatty acids was performed using Lipozyme® TL IM. The performance of the acidolysis reaction was evaluated using 1H-NMR spectroscopy and verified in selected cases using gas chromatography. The best performing conditions involved carrying out the acidolysis reaction at 60℃ with a 1.2 w/w ratio of the fatty acids to coconut oil and 10% enzyme loading for 72 h. This resulted in the incorporation of 26.61% and 9.86% of 8-methyl-6-trans-nonenoic acid and 8-methylnonanoic acid, respectively, into the modified coconut oil product. This product can act as a potential delivery vehicle for these interesting compounds.
The extraction of olive oil produces annually huge quantities of Olive Mill Wastewater (OMW) that are considered as a source of pollution due to their high concentration in organic matter. This study aims to valorize Olive mill wastewater and investigates the effect of the extraction method and solvents on the contents and profiling of phenolic compounds and their antioxidant potential. It was revealed that the liquid-liquid method using ethyl acetate is the most effective followed by the maceration using chloroform/methanol (1:1), their polyphenol contents are respectively at 1.17 g GAE/L of OMW and 1.07 g GAE/L of OMW. In addition, the antioxidant activity was studied using ABTS test. It has shown that the methanolic extract has the best antioxidant activity at 15.75 mg/L. Moreover, we noticed a negative correlation between the phenolic compounds’ concentration and their antioxidant activity which indicates that the phenolic profile may not be the same in the different extracts that’s why a primary identification of the phenolic profile using UHPLC-MS was monitored and the results showed different chromatographic profiles between the samples.
Consumption of a high-fat diet (HFD) is associated with an increased risk of metabolic diseases, cancer, and neurological disorders, which are major global health concerns. In the present study, mice were fed a HFD containing 40% fat and 0.5% or 1.0% acylated steryl-β-glucosides (ASG) and their gut microbiota was compared to that of mice fed with a low-fat diet (LFD). After 55 d, the epididymal fat weight was higher in the HFD and ASG groups than in the LFD group; however, the epididymal fat weight was lower in the ASG group than in the HFD group. The abundance of gut microbiota increased with HFD in obese micespecific Bacillota, but decreased when ASG was added to the HFD. The number of intestinal bacteria involved in the production of carcinogenic secondary bile acids was increased by the consumption of HFD, but decreased by the addition of ASG to HSD. This finding may indicate the gut bacteria-mediated health benefits of ASG.
In this study, we report the successful preparation of reduced graphene oxide modified zinc oxide (rGO-ZnO) composites from cocoa shells. Synthesis of rGO-ZnO was carried out using the Hummer method and thermal reduction. The electrode material was comprehensively characterized using fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy & Energy Dispersive X-ray (SEM-EDX). The photoelectrocatalytic performance of the prepared composite electrodes was evaluated using various electrochemical techniques, including Linear Sweep Voltammetry (LSV), Cyclic Voltammetry (CV), and Multi Pulse Amperometry (MPA). The FTIR analysis of rGO-ZnO exhibited distinct bands corresponding to C-O at 1022 cm-1, C=C at 1600 cm-1, and Zn-O at 455 cm-1. The XRD analysis revealed characteristic peaks at 26.6º, 29.2º, 36.2º, 44.04º, 47.58º, and 64.4º, confirming the presence of key crystalline phases. SEM-EDX analysis of rGO-ZnO revealed a rough surface morphology with bright white and black regions, signifying the coexistence of ZnO and rGO with carbon, oxygen, and zinc contents of 78.98%, 17.46%, and 3.56%, respectively. The investigations involved the photoelectrochemical profiles of methylene blue organic dyes at different concentrations, ranging from 0.5 ppm to 3.0 ppm. The acquired findings offer valuable understanding into the photoelectrocatalytic effectiveness of the composite electrodes containing rGO-ZnO, suggesting their potential use in potential scenarios involving the revitalization of the environment in industrial water systems.