Effects of thermal treatment on the characteristics quality of some Ghanaian vegetable oils (palm, coconut and groundnut)

Introduction: Vegetable oils contain natural antioxidants and other properties reported to impart anti-diabetic properties when consumed, in animal study. In humans however, these oils are subjected to high temperatures during cooking before consumption. High temperature tends to affect the characteristic quality and potential to impart on health benefits such as antidiabetic properties. The objective of this work was to determine the characteristics quality of vegetable oils after thermal treatment that equates to temperatures oils are subjected to during food processing/cooking.Methodology: Three portions of 200g of each fresh unrefined red palm oil, coconut oil and groundnut oils in three conical flasks T1, T2 and T3 were heated to room temperature 28oC (T1) to 100o C in boiling water (T2) and to 200o C in electric cooker oven (T3) for 10 minutes. Acid, iodine, peroxide, saponification, unsaponification values of the oils, Phytoconstituents (Flavanoids, polyphenols saponins etc) and antioxidant (Vitamin A&C) and DPPH (1,1-Diphenyl-2-Picrylhydrazyl) Radical Scavenging Activity were then determined after cooling to room temperature. Results: Coconut oil heated to 200˚C had the least Acid value of 2.89±0.135 whiles Palm oil heated to 100 ˚C had the highest value of 19.57±0.165. There were no peroxides formed in Coconut and Palm oils at 28 ˚C as well as Palm oil at 100 ˚C. However, peroxides were highest in Coconut oil at 200˚C with value of 15.28±2.315. Saponification value of groundnut oil at 28 ˚C was the least at 89.52 ± 2.18 and 296.57±1.045 the highest in coconut oil at 200 ˚C. Heating however increased the unsaponifiable matter in all the vegetable oils used. Total antioxidant capacity was not significantly changed across the temperature treatment. Total phenolic content was not significantly changed for palm oil but was significantly increased at 100C for coconut and groundnut oilsConclusion: The quality of the oils in terms of acid value, iodine vale, peroxide value and saponification value, total antioxidant and phenolic content were retained after one heat treatment. This implies the quality of the oils are maintained after a single heating. The oils may still retain antidiabetic property when consumed after processing.

United States Dietary Trends Since 1800: Lack of Association Between Saturated Fatty Acid Consumption and Non-communicable Diseases

We reviewed data on the American diet from 1800 to 2019.Methods: We examined food availability and estimated consumption data from 1808 to 2019 using historical sources from the federal government and additional public data sources.Results: Processed and ultra-processed foods increased from <5 to >60% of foods. Large increases occurred for sugar, white and whole wheat flour, rice, poultry, eggs, vegetable oils, dairy products, and fresh vegetables. Saturated fats from animal sources declined while polyunsaturated fats from vegetable oils rose. Non-communicable diseases (NCDs) rose over the twentieth century in parallel with increased consumption of processed foods, including sugar, refined flour and rice, and vegetable oils. Saturated fats from animal sources were inversely correlated with the prevalence of NCDs.Conclusions: As observed from the food availability data, processed and ultra-processed foods dramatically increased over the past two centuries, especially sugar, white flour, white rice, vegetable oils, and ready-to-eat meals. These changes paralleled the rising incidence of NCDs, while animal fat consumption was inversely correlated.

The Effect of Different Vegetable Oils on Cedar Wood Surface Energy: Theoretical and Experimental Fungal Adhesion

Despite having been used for ages to preserve wood against several effects (biological attack and moisture effects) that cause its degradation, the effect of vegetable oils on the cedar wood physicochemical properties is poorly known. Thus, in this study, the hydrophobicity, electron-acceptor (γ+), and electron-donor (γ−) properties of cedar wood before and after treatment with vegetable oils have been determined using contact angle measurement. The cedar wood has kept its hydrophobic character after treatment with the different vegetable oils. It has become more hydrophobic quantitatively with values of surface energy ranged from −25.84 to −43.45 mJ/m2 and more electron donors compared to the untreated sample. Moreover, the adhesion of four fungal strains (Penicillium commune (PDLd”), Thielavia hyalocarpa, Penicillium commune (PDLd10), and Aspergillus niger) on untreated and treated cedar wood was examined theoretically and experimentally. For untreated wood, the experimental adhesion showed a positive relationship with the results obtained by the extended Derjaguin–Landau–Verwey–Overbeek (XDLVO) approach which found that all fungal strains could adhere strongly to the cedar wood material. In contrast, this relationship was not always positive after treatment. The Environmental Scanning Electron Microscopy (ESEM) has shown that P. commune (PDLd10) and A. niger were found unable to adhere to the wood surface after treatment with sunflower and rapeseed oils. In addition, the results showed that the four fungal strains’ adhesion was decreased with olive and linseed oils treatment except that of P. commune (PDLd10) treated with linseed oil.

Model Validation for the Heat Transfer in Gasket Plate Heat Exchangers Working with Vegetable Oils

Many models for accurately predicting the performance of gasket plate heat exchangers were developed in the last decades, grouped in three categories: empirical, semi-analytical or theoretical/numerical, with the view to saving materials and energy through correct design of industrial equipment. This work addresses one such model, namely Lévêque correlation modified by Martin and by Dović, which is promising due to the correct assumption of the flow in sine duct channels and the consideration of energy losses caused by flow reversal at plate edges and the flow path changing when entering the chevron angle. This model was validated by our own experimental data under industrial conditions for vegetable oils processing, both in laminar flow (Re = 8–42) and fully developed turbulent flow (Re = 446–1137). Moreover, in this study, particular values for constants/parameters of the model were determined for the corrugation inclination angle relative to vertical direction equal to 30°. Through statistical analysis, this study demonstrates that this particularized form of the generalized Lévêque correlation can be used with confidence.

Determination of 3-Monochloropropanediol and Glycidol in Food Products

Due to the increasing globalization of food markets, there are evolving new challenges for maintaing food safety. The current problem is the development of analytical methods for 3-monochloropropanediol ester and glycidol ester, which are food contaminants of concern for the scientific community. The levels of 3-monochloropropanediol ester and glycidol ester in certain food products are controlled by the European legislation. However, the maximum allowed concentrations and uptake limits for various food products are permanently revised. Therefore, we aimed to determine 3-monochloropropanediol ester and glycidol ester in various food products, which may contain vegetable oils. We analyzed food samples obtained from local food shops, predominantly low-priced products, which are more likely to contain vegetable oils, and adulterated milk fat. The levels of 3-monochloropropanediol ester and glycidol ester were determined indirectly by analyzing free 3-monochloropropanediol and glycidol ester obtained by hydrolysis and derivatized with phenylboronic acid. Samples were analyzed by GC-MS/MS on a triple-quad mass spectrometer.

Synergistic Study of Solid Lubricant Nano-Additives Incorporated in canola oil for Enhancing Energy Efficiency and Sustainability

In recent years, with the development of eco-friendly lubricants, different vegetable oils have been studied and found to improve the overall tribological performance compared to petroleum-based oils. Being one of the commonly used vegetable oils, canola oil has become popular due to its non-toxicity and low cost. However, this bio-lubricant lacks tribological performance compared to petroleum-based oils. To improve its performance, sustainable solid additives such as graphene nanoplatelet (GNP) and hexagonal boron nitride (hBN) have recently gained the researcher’s attention. While incorporating nanomaterials in the oil as additives is a promising way to improve base oil’s performance, the excessive use of nanoparticles can introduce undesirable effects. This study investigated canola oil’s tribological performances with the addition of 0.5, 1.0, 1.5, and 2.0 wt.% GNP and 0.5, 1.0, and 1.5 wt.% hBN nanoparticles. The dynamic viscosities of these seven settings showed higher viscosity for GNP-incorporated oils compared to that with hBN. The boundary lubrication regime was targeted for the coefficient of friction (COF) and wear analyses during each pin on the disk test. It was observed that for the GNP, 1.5 wt.% provided the minimum COF (52% less than base oil), whereas, for the hBN, 1.0 wt.% provided the lowest (40% less than base oil) values. Based on these insights, three nano lubricant mixtures were formulated by incorporating both GNP and hBN settings in different ratios. These mixtures provided an optimum positive synergy by reducing 56% friction and 90% wear compared to the base oil. These percentage values were significantly more compared to both GNP and hBN based lubricants in their individual settings. These improvements in the mixture were due to a composite film formed which protected the interacting surfaces and also due to the polishing mechanisms. Therefore, incorporating both these nanoparticles in canola oil could reduce friction and wear and thus help in better energy conservation.