Polycaprolactone (PCL)-based films integrated with hairy cellulose nanocrystals and silver nanoparticles for active Tilapia packaging applications.

The migration of metal ions to the food matrix has been always a challenge in the production of active food packaging films. In this study, it was tried to evaluate the idea of using hairy cellulose nanocrystals (HCNs) in controlling the migration of Silver Nanoparticles (AgNPs) from polycaprolactone (PCL)-based films to the Tilapia fish. HCNs and the final films (integrated with various amounts of HCNs and AgNPs) were evaluated physicochemically and mechanically. Tilapia fish were packed using the films and after specific periods, the fish samples were assessed microbiologically and physiochemically. According to the results, incorporating NPs into PCL films enhanced tensile strength, elasticity, and toughness making the films more resistant to breakage and deformation under stress. The introduction of HCNs reduced the surface roughness level, decreasing AgNPs migration, but also accelerated the degradation rate. Films with [1% AgNPs +2% HCNs] and [1% AgNPs] had the lowest and highest water vapor transmission rate. The use of AgNPs (1%) + HCNs (2%) incorporated into PCL films resulted in a lower pH value, TVB-N, TBARs, and PV. It also decreased microbial activities in samples in comparison to the control. Therefore, the idea of using HCNs along with antibacterial metal-based nanoparticles can control the rate of ion migration.

Effects of adding green tea extract on the oxidative stability and shelf life of sunflower oil during storage.

This study aimed to compare different concentrations effect of green tea extract (GTE) (200, 400, and 800 ppm) with TBHQ (75 ppm) in extend the shelf-life of sunflower oil (SO) and to evaluate the protective effect of GTE on the oxidation of refined SO. The sample's peroxide value (PV), acidity value (AV), anisidine value (pAV), Totox value (TV), oxidative stability, and total phenol content (TPC) were analyzed at specific intervals during 12-month at 25 °C and 60-day at 60 °C. The optimum kinetic model corresponding to the first order for PV, TV, and pAV was obtained at 25, 35, and 45 °C. SO containing GTE (800 ppm) had a similar performance to TBHQ at 25 °C and 60 °C and possessed a longer shelf life than samples treated with TBHQ. Due to synthetic antioxidant's health risk and toxicity, GTE can be a good substitute for TBHQ in the edible oil industry.

Electrospun zein nanofibers containing anthocyanins extracted from red cabbage (Brassica oleracea L.).

This study aims to fabricate and characterize the zein nanoribbons loaded with different concentrations (2.5, 3, 3.5, 4, and 4.5°wt%) of the anthocyanins extracted from red cabbage through the electrospinning technique. It was demonstrated that an increase in anthocyanin concentration caused an increase in viscosity and electrical conductivity without any significant change in the surface tension of the electrospinning solution. It was shown by scanning electron microscopy that an increase in anthocyanins concentration reduced the porosity of the bead-free ribbons compared with blank zein. The Fourier transform infrared spectroscopy analysis, X-ray diffraction patterns, and differential scanning calorimetry results reflected the presence of significant molecular interactions between zein and anthocyanins. Zein-anthocyanins showed high encapsulation efficiency of close to 100%. As a result, it can conclude that electrospinning is a promising method to encapsulate functional ingredients like anthocyanins.

Production of partially hydrogenated soybean oil with low trans-fatty acids using surface dielectric barrier discharge cold plasma.

This study examined the feasibility of applying surface dielectric barrier discharge cold plasma (SDBDCP) to partially hydrogenate crude soybean oil. The oil sample was treated for 13 h using SDBDCP at 15 kV with 100% hydrogen gas under room temperature and atmospheric pressure. Fatty acid composition, iodine value, refractive index, carotenoid content, melting point, peroxide value, and free fatty acids content (FFA) were investigated during SDBDCP treatment. Analysis of fatty acid composition demonstrated an increase in the content of saturated and monounsaturated fatty acids (from 41.32% to 55.3%) and a decrease in the content of polyunsaturated fatty acids (from 58.62% to 40.98%), which resulted in a reduction of the iodine value to 98.49 over the treatment time. Also, the fatty acid profile indicated that the total detected level of trans-fatty acids was very low (0.79%). After a 13-h treatment, the samples showed a refractive index of 1.4637, melting point of 10°C, peroxide value of 4.1 meq/kg, and FFA content of 0.8%. In addition, the results revealed a 71% decline in the carotenoid content of the oil sample due to the saturation of their double bonds. Therefore, these findings suggest that SDBDCP can be effectively used for hydrogenation along with bleaching oil.

Chemical compositions and antioxidant activity of Heracleum persicum essential oil

ABSTRACT In this study essential oil of the aerial parts of Heracleum persicum a spice widely used in Iran was isolated by conventional hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD) techniques. The extraction yield was determined and the chemical compositions of essential oils were identified by the application of gas chromatography/mass spectrometry (GC/MS). The antioxidant activity was determined by two different methods: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and oven test methods. Although the main compounds of essential oils by the both extraction methods were similar, the essential oil extracted by HD with lower extraction efficiency showed more diverse compounds. The evaluation of antioxidant activity of the essential oil measured by delay in sunflower oil oxidation indicated that the antioxidant activity was dependent on the concentration which increased when higher concentrations of the essential oils were applied. The results of DPPH radical assay also indicated that the percentage of inhibition increased with increasing of essential oil concentration and IC50 value for essential oil extracted by MAHD method was obtained 1.25 mg/mL. Therefore the Heracleum persicum essential oil might be recommended for use as a flavoring agent and a source of natural antioxidants in functional foods, formulation of the supplements and in medicinal due to numerous pharmacological activities.

The effect of germination on phenolic content and antioxidant activity of chickpea.

Germination is one of the most effective processes to improve the quality of legumes. Vitamins and some other compounds that might be considered beneficial as antioxidants, often change dramatically during the course of germination. Antioxidants might be defined as compounds which are capable of preventing, delaying or retarding the development of rancidity or other flavor deterioration in foods or as protective factors against the oxidative damage in the human body. In this research, three different solvents were employed to extract the phenolic compounds present in chickpea seeds and sprouts. Total phenolic contents were measured by Folin Ciocalteau method and the antioxidant activity was determined by two different methods including the assay of hydroxyl radical scavenging activity and the oven test method. For the later, different concentrations of extracts (0.02, 0.04, 0.06, 0.08 and 0.1% w/w) were added to tallow and the stabilities of the treatments were determined. Peroxide value and induction period measurements were used as means to evaluate the antioxidant activities. The results indicated that germination process modifies the antioxidant activity. Although the amount of phenolic compounds was higher when acetone solvent was employed, methanolic extract indicated better hydroxyl radical scavenging activity. The evaluation of the antioxidant activity of the extracts activity was concentration-dependent by delaying the indicated oxidation and increased when higher concentrations of the extracts were applied. Therefore, chickpea sprout flour or extract might be used as a source of natural antioxidants in functional foods or in the formulation of the oil-based supplements or medicine in the form of capsule.