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The purpose of this paper is to investigate the performance of bio-based lubricants (BBL), namely, palm mid-olein (PMO) enriched with an antioxidant agent, tertiary-butylhydroquinone (TBHQ) and a viscosity improver, ethylene-vinyl acetate (EVA), in journal bearing (JB) applications.

Samples of the BBL were prepared by blending it with TBHQ and EVA at various blending ratios. The oxidative stability (OS) and viscosity of the BBL samples were examined using differential scanning calorimetry and a viscometer, respectively. Meanwhile, their performance in JB applications was evaluated through the use of a JB test rig with a 0.5 length-to-diameter ratio at various operating conditions.

It was found that the combination of PMO + TBHQ + EVA demonstrated a superior oil film pressure and load-carrying capacity, resulting in a reduced friction coefficient and a smaller attitude angle compared to the use of only PMO or VG68. However, it was observed that the addition of TBHQ and EVA to the PMO did not have a significant impact on the minimum oil film thickness.

The results would be quite useful for researchers generally and designers of bearings in particular.

This study used PMO as the base stock, and its compatibility with TBHQ and EVA was investigated in terms of its OS and viscosity. The performance of this treated BBL was evaluated in a hydrodynamic JB.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2023-0363/

The purpose of the present study was to evaluate the effect of tert-Butylhydroquinone (TBHQ) on the quality characteristics of low-fat Kalari, a hard and dry cheese. The products treated with TBHQ were assessed for various oxidative stability and storage-quality parameters.

Low-fat Kalari was prepared and treated with different concentrations of TBHQ (0, 200, 300 ppm) and aerobically packaged within low-density polyethylene pouches and assessed for physicochemical, microbiological and sensory characteristics under refrigerated (4 ± 1°C) conditions.

TBHQ showed a significant (p < 0.05) effect on the lipid stability, as the treated products exhibited significantly (p < 0.05) lower TBARS (mg malonaldehyde/kg) values for the entire period of storage. pH showed a significant (p < 0.05) decreasing trend, whereas titratable acidity followed a significant (p < 0.05) increasing trend with storage period in control as well as treated products. No significant (p > 0.05) effect was observed on the microbiological characteristics of the products, as TBHQ-treated products showed comparable (p > 0.05) values for total plate count, psychrophillic count and yeast and mould count. Significantly (p < 0.05) higher scores were observed for various sensory parameters of the treated products.

TBHQ successfully improved the storage quality of low fat Kalari during refrigerated (4 ± 1°C) storage and may be commercially exploited as an antioxidant in Kalari and other cheese like products.

This paper aims to evaluate the effect of different fiber sources and tert-butylhydroquinone (TBHQ) on the quality characteristics of chicken harrisa.

An attempt was made to develop fiber-enriched chicken harrisa, a meat-based product, by incorporating optimum level of different fiber sources, viz., oat bran (10 per cent) or wheat bran (10 per cent) or barley bran (5 per cent). The products developed with optimized level of fiber were further treated with TBHQ (200 ppm) and were aerobically packaged in low-density polyethylene pouches along with control and assessed for various storage quality parameters under refrigerated (4 ± 1°C) conditions. The products were evaluated for various physicochemical, microbiological and sensory parameters at regular intervals of 0, 7, 14 and 21 days.

A significant (p < 0.05) increase was observed in the fiber content of the products prepared with oat bran (10 per cent) or wheat bran (10 per cent) or barley bran (5 per cent). TBHQ showed a significant (p < 0.05) effect on the lipid oxidative stability, as the treated products exhibited significantly (p < 0.05) lower thiobarbituric acid-reactive substance (mg malonaldehyde/kg) values for the entire period of storage. No significant (p > 0.05) effect was observed on the microbiological characteristics of the products. Sensory parameters showed significant (p < 0.05) decreasing trend for control as well as TBHQ-treated products throughout the period of storage; however, significantly (p < 0.05) higher scores were observed for treated products in comparison to control.

Fiber-enriched chicken harrisa was developed by incorporating oat bran (10 per cent) or wheat bran (10 per cent) or barley bran (5 per cent) in the formulation. TBHQ successfully improved the lipid oxidative stability and storage quality of fiber-enriched chicken harrisa during refrigerated (4 ± 1°C) storage and may be commercially exploited to improve the storage quality of the product.

The purpose of this paper is to evaluate the oxidative stability of soybean oil added by Lentinus edodes and Agaricus blezei extracts in accelerated storage test.

The following treatments were subjected to accelerated storage test in an oven at 60°C for 15 days: Control (soybean oil without antioxidants), TBHQ (soybean oil+100 mg/kg of TBHQ), BHT (soybean oil+100 mg/kg of BHT), L. edodes (soybean oil+3,500 mg/kg of L. edodes extract) and A. blazei (soybean oil+3,500 mg/kg of A. blazei extract). The samples were taken every three days and analyzed for peroxide values and conjugated dienes.

At the end of 15 days, the treatments TBHQ, A. blazei, L. edodes, Control and BHT showed 6.47, 8.81, 41.53, 71.28 and 78.40 meq/kg, respectively, for peroxide values and 0.37, 0.40, 0.67, 1.07 and 1.00 per cent, respectively, for conjugated dienes.

The research indicates that mushrooms may be a promising source of natural antioxidants. Therefore, natural extracts of mushrooms can be applied to vegetable oils as a way to reduce the degradation caused by lipid oxidation.

This research aims to evaluate the antioxidant potential of oregano extract (OE), as well as its isolated and synergistic effect when applied to soybean oil (SO) under thermal oxidation.

In order to determine the antioxidant activity of oregano extract and its synergistic effect with tert‐butylhydroquinone (TBHQ), thermal oxidation was performed using the following treatments: SO, SO with 50 mg/kg of TBHQ, SO with 3,000 mg/kg of OE, and SO with 3,000 mg/kg of oregano extract and 50 mg/kg of TBHQ (mixture). The treatments underwent heating at 180°C for 20 hours, and analyses of oxidative stability, total polar compounds, tocopherols and fatty acids composition were performed. The results obtained were subjected to analysis of variance and Tukey test for averages at 5 percent, using the program ESTAT version 2.0.

Considering the results of antioxidant activity and total phenolic compounds, it was possible to verify that the ethanolic extract of oregano has presented antioxidant potential. Furthermore, considering the results obtained in the analyses of oxidative stability, polar compounds, tocopherols and fatty acids profile, it was possible to observe that the extract has prevented lipid oxidation when added to SO.

The study offers information on the use of natural antioxidants as an alternative to the use of synthetic antioxidants, which can be considered toxic.

The objective of this study was to evaluate the antioxidant effect of oregano and thyme extracts isolatedly and combinedly applied in soybean oil.

Soybean oil containing 3,000 mg/kg of oregano and thyme oleoresins and the mixture of both, as well as soybean oil containing TBHQ (50 mg/kg) and soybean oil free of antioxidants, were subjected to accelerated oven test (60°C/10 days). Samples were collected every two days and analyzed as to their peroxide and conjugated diene values.

The mixture of oleoresins and consequent increase of concentration were as effective as the antioxidant TBHQ.

These studies may prove to be beneficial to the exploitation of natural antioxidant sources for the preservation and/or extension of raw and processed food shelf life. Therefore, they could also be applied in the area of pharmaceuticals for the protection of human life.

This study offers information on the use of natural antioxidants as an alternative to the use of synthetic antioxidants, which might be considered toxic.

The purpose of this paper is to evaluate the antioxidant activity of ginger ethanol extract in soybean oil under thermoxidation.

A total of four treatments were used: soybean oil free of synthetic antioxidants, soybean oil containing 2,500 mg/kg of ginger extract, soybean oil containing 50 mg/kg of TBHQ, soybean oil containing the mixture of natural extract, and TBHQ in the before‐cited concentration. The treatments were discontinuously submitted to plates heated at 180°C, for 20 hours. Samples were removed in the times of 0, 4, 8, 12, 16 and 20 hours of heating and they were analyzed as to their oxidative stability, total polar compounds, peroxide and conjugated diene values.

The results showed the efficiency of the ginger extract in protecting the oil against lipid oxidation. It could be concluded that ginger extract might be indicated as an additive that acts against lipid oxidation and, consequently, increases shelf life of food.

These studies may prove to be beneficial to the exploitation of natural antioxidant sources for the preservation and/or extension of raw and processed food shelf life. Therefore, they could also be applied in the area of pharmaceuticals for the protection of human life.

This study offers information on the use of natural antioxidants as an alternative to the use of synthetic antioxidants, which might be considered toxic.

The effect of the addition of red palm olein (RPO) as a natural antioxidant to sunflower (SF) on chemical properties and deep-frying oxidative stability of resultant oil during storage.

RPO was added to SF at different levels 0, 5, 10, 15, 20, 25, 50, 75 and 100 (w/w), and potato chips were fried in oil blends repeatedly at 180 °C for 2.5 min for five days to evaluate the effect on chemical properties and oxidative stability.

The results revealed that linoleic acid and total polar compound (TPC) contents decreased in all RPO and SF resultant oil after five days of storage. Colour significantly (p = 0.05) decreased, while peroxide and iodine values were significantly lowered during storage. The oxidative stability increased significantly in the resultant oil. However, an increase in free fatty acid (FFA) before frying significantly reduced with repeated frying of resultant oil during storage. RPO (5–75%) therefore retards oxidative rancidity in the resultant oil after repeated deep frying and storage.

SF oil is high in polyunsaturated fatty acids but prone to oxidation upon heating and storage. RPO is an important ingredient used in industrial frying rich in phytonutrients and a better replacement to synthetic antioxidants. This study indicated that supplementing SF oil with RPO may be recommended to improve the oxidative stability of oils during frying.

This study aims to deal with the evaluation of the antioxidant capacity of lyophilized hydroalcoholic extracts of red peppers in natura. Furthermore, preference was evaluated for the taste and color of soybean oil added red pepper extracts.

The antioxidant capacity was determined by four methods. The content of phenolic compounds, carotenoids and ascorbic acid in the extracts was determined by chromatographic, spectrophotometric and titration methods, respectively.

The results showed that the highest antioxidant capacity was found in Malagueta pepper extract through reducing power (FRAP) method. In this same extract, high amount of phenolic compounds was found. However, the extracts of Bode and Dedo-de-moça peppers had higher amounts of carotenoids and ascorbic acid, respectively. Sensorially, the oil added extracts were preferred.

Red peppers are very popular and consumed worldwide, besides being constituted of important phytochemicals. Results showed high antioxidant activity in the extracts of peppers, and high content of phenolic compounds, carotenoids and ascorbic acid mainly in chili. This study highlights the importance of the extracts of red peppers, genus Capsicum, as a source of antioxidants, in addition to vegetable oils.

It is important to check the acceptance of the application of extract in vegetable oil, so it can be marketed as a natural antioxidant. This study provides valuable information about the antioxidant capacity of extracts of red peppers and its acceptance.

The purpose of this study is to compare the oxidative stability of non‐hydrogenated cottonseed oil with that of the partially hydrogenated oils commonly used as a deep‐fat frying medium by the restaurant industry when used to prepare French fries in order to reduce trans‐fatty acids.

Stability characteristics of non‐hydrogenated cottonseed oil and two hydrogenated oils, canola and soybean, were evaluated in deep‐fat frying applications. French fries were analyzed for total polar compounds, and the oils were analyzed for iodine, peroxide, p‐anisidine and totox values, and free fatty acids.

Canola and soybean oil had significantly lower iodine values than cottonseed oil. Free fatty acid values were not significantly different among the oils (0.256 per cent oleic acid). Initially cottonseed oil had higher peroxide, p‐anisidine, and totox values compared with canola and soybean oil. However, as days of frying increased, values trended closer together. Total polar compounds were similar. All oil types were comparable in terms of their stability characteristics under the conditions used in this study.

Research with additional food product and under more stressful conditions would be beneficial.

Hydrogenation increases trans‐fatty acid content. Consumption of trans‐fatty acids has been associated with increased risk of heart disease. Non‐hydrogenated cottonseed oil may be a viable alternative to popular hydrogenated oils currently used in the restaurant setting.

Restaurants are being pressured by health officials to choose healthier oil. This research article can help restaurants make an informed choice.