Cytooxidative effects of α‐tocopherol and ascorbyl palmitate on thermal oxidation of canola oil

Canola oil, with and without added α‐tocopherol and ascorbyl palmitate, was used to deep‐fat frying potatoes once per day for 10 day or once per week for 10 weeks. Changes in chemical and physical properties were monitored. Refractive index, free fatty acids and absorbance at 232 and 270 nm increased with frying time. Smoke point, ‘L’ color index, iodine value and the C_18 : 2/C_16 : 0 ratio in the oil decreased with the frying time. According to smoke point, which shows the time of the oil should be discarded, canola oil without antioxidant (control) can be used safely 8 times daily or 7 times weekly. For canola oil with antioxidant (oil + α‐tocopherol + ascorbyl palmitate( the smoke point did not decrease below 170°C in both daily and weekly fryings. This showed that canola oil with antioxidant could be used safely at least 10 times for both frying intervals. In both daily and weekly fryings, the addition of 200 ppm α‐tocopherol and 200 ppm ascorbyl palmitate increased the oxidative stability of canola oil.     

Antioxidative effects of alpha-tocopherol and ascorbyl palmitate on thermal oxidation of canola oil

Canola oil, with and without added alpha-tocopherol and ascorbyl palmitate, was used to deep-fat frying potatoes once per day for 10 day or once per week for 10 weeks. Changes in chemical and physical properties were monitored. Refractive index, free fatty acids and absorbance at 232 and 270 nm increased with frying time. Smoke point, 'L' color index, iodine value and the C18:2/C16:0 ratio in the oil decreased with the frying time. According to smoke point, which shows the time of the oil should be discarded, canola oil without antioxidant (control) can be used safely 8 times daily or 7 times weekly. For canola oil with antioxidant (oil + alpha-tocopherol + ascorbyl palmitate), the smoke point did not decrease below 170 degrees C in both daily and weekly fryings. This showed that canola oil with antioxidant could be used safely at least 10 times for both frying intervals. In both daily and weekly fryings, the addition of 200 ppm alpha-tocopherol and 200 ppm ascorbyl palmitate increased the oxidative stability of canola oil.     

Determination of Iron in Edible Oil by FAAS After Extraction with a Schiff Base

The synthesis of a new Schiff base has been achieved by condensation reaction of 1,3-diamino-2-propanol and 2-hydroxy-5-methoxy-benzaldehyde in alcoholic media. The Schiff base was characterized by elemental analysis, IR, UV–Visible, ¹H-NMR, and ¹³C-NMR spectroscopy and used for the extraction of iron in liquid edible oils. Iron complex with the Schiff base was investigated in order to determine experimental conditions of the complexation. The extraction of iron from oils to aqueous phase was succeeded by the complexation with the Schiff base. A central composite design was employed in order to optimize the extraction conditions of iron. Optimum conditions for the iron extraction with N,N′-bis(5-methoxy-salicylidene)-2-hydroxy-1,3-propanediamine were found to be 19.3 °C, 2.1 mL g^?1, 10.0 min for the temperature, the ratio of the volume of used Schiff base solution to the amount of oil, and the stirring time, respectively. Method validation was performed with recovery experiments in the analysis of the oil-based metal standard by flame atomic absorption spectrometry, limit of detection, and the relative standard deviation of the proposed method were found to be 0.09 μg g^?1 and 1.04 %, respectively. Additionally, an alternative determination procedure (inductively coupled plasma optical emission spectrometry) was applied for the comparison. This paper describes a simple, cheap, rapid, efficient, sensitive, and accurate alternative analytical method for the iron determination in oils. The proposed method was applied on six different oil samples and the iron concentration was found in the range of 0.38–0.70 μg g^?1.     

A New and Simple Approach for Decontamination of Food Contact Surfaces with Gliding Arc Discharge Atmospheric Non-Thermal Plasma

In this study, a gliding arc discharge (GAD) microplasma system was designed, and its decontamination effect was investigated on stainless steel (SS), silicone (Si), and polyethylene terephthalate (PET) surfaces artificially contaminated with 8.15 ± 0.28 log cfu/mL of Escherichia coli and 6.18 ± 0.21 log cfu/mL of Staphylococcus epidermidis. Each of the contaminated surfaces was treated with high purity air (79% nitrogen and 21% oxygen) or nitrogen plasmas for 1–10 min at varying rates of gas flow. Significant reductions of 3.76 ± 0.28, 3.19 ± 0.31, and 2.95 ± 0.94 log cfu/mL in S. epidermidis, and 2.72 ± 0.82, 4.43 ± 0.14, and 3.18 ± 0.96 log cfu/mL in E. coli on SS, Si, and PET surfaces, respectively, were achieved after 5 min of plasma treatment by using nitrogen as the plasma forming gas (p < 0.05). The temperature changes of each surface during plasma generation were lower than 35 °C and were not affected by the type of plasma forming gas. Additionally, morphological changes in the structure of E. coli and S. epidermidis after GAD plasma treatments were demonstrated using scanning electron microscopy (SEM).     

Nail biology and nail science

The nail plate is the permanent product of the nail matrix. Its normal appearance and growth depend on the integrity of several components: the surrounding tissues or perionychium and the bony phalanx that are contributing to the nail apparatus or nail unit. The nail is inserted proximally in an invagination practically parallel to the upper surface of the skin and laterally in the lateral nail grooves. This pocket-like invagination has a roof, the proximal nail fold and a floor, the matrix from which the nail is derived. The germinal matrix forms the bulk of the nail plate. The proximal element forms the superficial third of the nail whereas the distal element provides its inferior two-thirds. The ventral surface of the proximal nail fold adheres closely to the nail for a short distance and forms a gradually desquamating tissue, the cuticle, made of the stratum corneum of both the dorsal and the ventral side of the proximal nail fold. The cuticle seals and therefore protects the ungual cul-de-sac. The nail plate is bordered by the proximal nail fold which is continuous with the similarly structured lateral nail fold on each side. The nail bed extends from the lunula to the hyponychium. It presents with parallel longitudinal rete ridges. This area, by contrast to the matrix has a firm attachment to the nail plate and nail avulsion produces a denudation of the nail bed. Colourless, but translucent, the highly vascular connective tissue containing glomus organs transmits a pink colour through the nail. Among its multiple functions, the nail provides counterpressure to the pulp that is essential to the tactile sensation involving the fingers and to the prevention of the hypertrophy of the distal wall tissue, produced after nail loss of the great toe nail.