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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.

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.

The purpose of this study was to study the effect of kiwifruit juice and tumbling in improving tenderness and to access antioxidant potential of kiwifruit juice.

Three treatment groups were made: Spent hen meat was subjected to still marination (SM) and tumbling marination (TM). This meat was used for preparation of whole muscle chicken nuggets and compared with control (without marination) nuggets (Con). These treatments were subjected to analysis of physicochemical characteristics, textural quality, lipid oxidation and sensory quality.

SM and TM exhibited higher moisture content and lower protein and fat content than Control SM and TM showed significant (p = 0.132) reduction in firmness from 5.1 to 2.3 and 1.2 Kg/cm², respectively, and toughness from 14.1 to 6.2 and 3.3 Kg-sec/cm², respectively, as observed by Warner-Bratzler shear and improvement in texture profile values. Sensory scores for texture, juiciness and overall acceptability were also better for SM and TM. Significant (p = 0.007) reduction was observed in lipid oxidation parameters of SM and TM. Thiobarbituric acid (TBA) values (on 0 day) for SM and TM were 0.18 and 0.15 as compared to 0.28 mg/kg of malonaldehyde for control. Peroxide values (PV) were also lower for SM and TM as 0.44 and 0.33, which were lesser than control (0.62 meq. peroxide/kg). The values for PV, TBA and free fatty acid increased with increase in storage period in all treatment groups. However, the antioxidant activity of kiwifruit juice persisted during whole storage period evidenced by lower values of lipid oxidation parameters for SM and TM than Control at each storage interval.

Further research may be carried out to compare the tenderizing potential of kiwifruit juice with other plant proteases and physical tenderizing techniques. Spent hen meat utilization can be done with greater efficiency by using such techniques in meat caterings.

Spent hen meat utilization can done with greater efficiency by using such techniques in meat caterings.

Marination with kiwifruit juice improved the quality characteristics of chicken nuggets made from spent hen meat without altering its sensory quality. Tumbling was found to be beneficial in enhancing the tenderizing effect. Therefore, marination with kiwifruit juice can be used as a processing technology to use spent hen meat in preparing value added products.

The purpose of this study is to evaluate the effect of the addition of dried lemongrass leaves (DLGL) powder, at different levels, on phenolics content, antioxidant activities, consumer acceptance and the inhibition of lipid peroxidation of roasted coffee (RC).

DLGL powder was incorporated at the levels of 0%, 2.5%, 5.0%, 7.5% and 10% of RC weight. The total flavonoids (TF), total phenolics (TP) and antioxidant activity measured using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and reducing power assay of RC, DLGL and binary mixture of them determined. The oxidative indices of coffee oil samples during storage were investigated. In addition, the sensory characteristics of RC fortified with different levels of DLGL powder were evaluated.

The TP content of DLGL powder was 1,100.32 mg/100 g DWb, nearly 1.2 times higher than found in RC beans. The TF content of RC enriched with 2.5%, 5.0%, 7.5% and 10% DLGL were found to be around 1.05, 1.10, 1.15 and 1.20 times higher than that in the control coffee samples. RC supplemented with various levels of DLGL powder showed higher DPPH radical scavenging and reducing power activities. At the end of the storage period (six months), the acid, peroxide, P-Anisidine and total oxidation value values of RC supplemented with 10% DLGL powder were about 1.94, 2.52, 2.60 and 2.59 times as low as in the control sample without any addition of DLGL powder, respectively. RC containing 2.5% and 5.0% DLGL powder had significantly (p < 0.05) the highest sensory scores. Consequently, the addition of DLGL in coffee at up to a 5% ratio may have potential health benefits.

RC containing 2.5% and 5.0% DLGL powder had significantly (p = 0.05) the highest sensory scores.

Consequently, the addition of DLGL in coffee at up to a 5% ratio may have potential health benefits.

The purpose of this paper is to determine the physicochemical properties of oil produced from Roselle seeds.

The oil was produced from the seeds by mechanical expression and the physicochemical properties of the oil determined using the AOAC methods.

The values of the physicochemical properties of oil from Roselle seed are saponification value 126.2, iodine value 111.2, viscosity 22.5 cp, refractive index 1.4472 and specific gravity 0.9558. The peroxide value varied between 6.0‐9.3 and 5.9‐9.0; and free fatty acid, 0.435‐2.300 and 0.510‐3.311 for fine and coarse samples, respectively. These values compared favourably with standard values, indicating that the oil extracted is edible.

The properties are useful in determining the suitability of the oil from the Roselle seeds as edible oil or for other industrial purposes.

The aim of the study was to analyse the quality changes in marinated herring meat depending on the moment of adding milk thistle.

One control (C) and two experimental groups were investigated: MH (milk thistle added to a marinade solution) and FH (fillets rubbed with milk thistle before marination). The basic chemical composition, the meat colour, heavy metals concentration, fatty acids profile, quality of lipids and antioxidant capacity were determined.

The occurrence of Fe, Mn, Cu and Zn was higher in the experimental group than in the control group throughout the marinating process. The peroxide value was higher from the first day in the control group than in the experimental groups. On the last day of the study, the peroxide value in the control group exceeded the maximum acceptable value. The highest level of Thiobarbituric Acid Reactive Substances was determined in the control group on the first day, and the lowest in the FH group. On the first day, the highest percentage of DPPH (2,2-Diphenyl-1-picrylhydrazyl) radical quenching was recorded in the FH group.

The results are the first to find that the addition of milk thistle to herring fillets in marinating process maintains or even improves the quality of the marinades. The process of previously coating the fillets in milk thistle and then marinating achieves a lower peroxide value, higher content of polyunsaturated fatty acids and a higher content of elements such as iron and manganese, which are very valuable for human health.

The purpose of this paper is to investigate the quality of the frying oil used in restaurants, fast food establishments, and confectionary stores. The compliance of used frying oils with the quality standards as determined by the peroxide value (PV) and the total polar materials (TPMs) is investigated by analyzing 375 samples of oil.

The PV was measured according to the national standard procedure number 4179, while the TPM was determined using a Testo 270 cooking oil tester. Frying oils with a PV>5 mEq/kg and a TPM>25 percent were considered to be non-edible. For a comparison of groups, the Mann-Whitney and Spearman correlation tests were used, and p<0.05 was considered significant.

The maximum TPM and PV recorded for frying oils in fast food restaurants were 97.5 percent and 77.9 mEq/kg, respectively. The results also revealed that 60 percent of samples were non-edible according to the TPM, while 58.9 percent of the oil samples were non-edible because of the PV. TPM and PV correlated well with each other (r=0.99, p<0.001) and with oil replacement intervals (r=0.90, p<0.001). The relationship between the TPM and PV was stronger in the polynomial model than the linear model. The following equation was obtained: peroxide (mEq/kg oil)=0.0043 TPM2 (%)+0.1587 TPM (%)–0.6152.

Considering the current limitations in official supervision by health authority, on-site self-monitoring of the TPM using the Testo 270 cooking oil tester by sellers as a solution seems a new approach. Food stores, restaurants, and confectionary stores should be equipped with TPM analyzers to determine the quality of the frying oil and the timely replacement of non-edible oils.

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.

Black cumin (Nigella sativa L.) is well known for its strong, hot, peppery taste and has many nutritional, pharmaceutical and traditional therapeutic uses. The aim of this study was to investigate the antioxidant effect of different solvent extracts of black cumin seed to retard lipid and protein oxidation in raw ground pork meat during refrigerated storage (4 ± 1°C) for nine days.

Black cumin extracts (BCEs) were prepared using different solvents, namely, ethanol, water, ethanol:water (60:40) and methanol:hot water (60:40). Extracts were analysed for total phenolic content (TPC), 1,1 diphenyl-2-picrylhydrazil (DPPH) radical scavenging activity and reducing power. Based on the results, water extract (WE) and ethanol–water extract (EHWE) of black cumin were selected and incorporated at 1.5 per cent into freshly minced pork meat and compared with a synthetic antioxidant, butylated hydroxytoluene (BHT; 100 ppm), in retarding lipid and protein oxidation. Treated and control samples were aerobically packed in low-density polyethylene bags for analysis of various parameters (pH, colour and odour score, peroxide, lipid and protein oxidation) during nine-day refrigerated storage study.

Results showed that BCEs had a good amount of TPC (4.4-7.4 mg gallic acid equivalents/g) and also DPPH scavenging activities (33.96-44.23 per cent), with WE and EHWE extracts showing highest reducing power and promising antioxidant capacity. Hence, BCEs (WE and EHWE) incorporated at 1.5 per cent into freshly minced pork meat was tested, compared to BHT (100 ppm) and control samples, in retarding lipid and protein oxidation during storage. In BCE-treated samples, thiobarbituric acid reacting substances, free fatty acids, peroxide, formation of protein carbonyls and off-odour or rancid odour development were lower than control and values were comparable with BHT. Incorporation of BCE did not negatively affect the colour of ground pork.

BCEs (WE and EHWE) at 1.5 per cent inhibited protein and lipid oxidation and it could be exploited commercially as an effective alternative in retarding oxidative deterioration of meat products.

The purpose of this pilot-scale study was to compare the quality of traditionally manufactured butters from local, small British producers with the quality of butters that are produced industrially.

Butter samples were obtained after supervised site inspections of three traditional-butter manufacturers and one large-scale butter producer. The samples were subject to initial microbiological, chemical and sensory testing, followed by a refrigerated shelf-life study over 24 weeks.

Traditional butters matched or exceeded the sensory quality of industrial butters, but spoilage microorganisms tended to grow faster on traditional butters. This seemed to be related to poorer water droplet dispersion in the manufacture of some of the traditionally made butters. Visible mould appeared on two of the traditional butters after eight weeks, but this occurred well after the nominal “best before” date.

Prolonged lockdowns due to the current coronavirus disease (COVID-19) pandemic pose a threat to the food supply chain, and food produced by local manufacturers may become increasingly important. However, are foods produced by local small-scale manufacturers of a quality comparable to that produced using large-scale production facilities? To the best of the authors' knowledge, there is no comparative study of the quality and shelf-life of traditionally-produced and industrially-produced butters. The current work presents such a comparison together with an outline of how the process of traditional butter-making differs from commercial production in Britain.