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This study aims to assess the influence of partial and simultaneous substitution of fat and sodium by hydrolyzed collagen and mix of herbs (MH) in chicken hamburgers, on the physical properties and proximal composition.

Five formulations were developed: (1) HCON–without adding collagen and MH; (2) C25M25–adding 25% of collagen and 25% of MH; (3) C25M50–adding 25% of collagen and 50% of MH; (4) C50M25–adding 50% of collagen and 25% of MH and (5) C50M50–adding 50% of collagen and 50% of MH. Chicken hamburgers were analyzed by proximal composition, sodium content, collagen and color analysis. The influence of treatments on texture profile, cooking performance and lipid oxidation of chicken hamburger was also investigated.

There was reduction in lipid and sodium for modified formulations compared with the HCON. There was great influence for some parameters, such as luminosity, cooking performance and texture profile. The formulation C50M50 showed the best cooking performance when compared to the others.

The formulation adding 50% of collagen and 50% of MH showed the highest yield and water retention (WR), with the least reduction in diameter and shrinkage, as well as presenting the best indexes of the texture profile and the lowest oxidation index, being recommended as the best combination of fat and sodium replacement.

Previous work has suggested that the adhesion between oil and metallic surfaces of an engine could be an important factor in determining crankcase cleanliness. It can be shown that it is only necessary to measure the spreading pressure of an oil on metal in order to get a direct measure of the work of adhesion, Surface tensions of lubrictaing oils vary very little and it can be assumed that the critical film pressure (C.F.P.) obtained with a given apparatus is an acceptable measure of the work of adhesion as well as of the spreading pressure. Oils of similar properties may vary tenfold in their C.F.P's. The addition of additives influences the spreading pressure, the largest increments in C.F.P. being given by dispersant and detergent additives.

This study aims to report the oxidation behaviors of the T91 ferritic/martensitic steel (T91 steel) and 304 austenitic stainless steel (304 steel) in supercritical water (SCW) at 600°C.

The microstructure, elemental distribution and phase structure of the oxidation layers derived from the corrosion of the T91 steel and 304 steel were analyzed by scanning electron microscopy, Oxford Instrument X-ray spectroscopy, electron scattered diffraction and transmission electron microscopy.

The oxidation layers on the T91 steel and 304 steel have duplex structure. The two steels all suffer internal oxidation, and the phase of the internal oxidation layers are indexed as Fe-Cr spinel, although their morphologies are different. The formation of a continuous Cr-rich layer is not detected because of the relatively low Cr content of the steels, which is attributed to the corrosion property.

The accelerated corrosion and corrosion mechanism of the T91 steel and 304 steel with low Cr occurring in SCW at 600°C was clarified.

Use of hydrotreated, hydrocracked and catalytically dewaxed base oils in hydraulic and industrial applications is increasing on a global scale. The hydrogenation and dewaxing processes involved in the manufacture of these products can result in base oils of exceptionally low aromatic content and sulphur level and raised viscosity index (VI). The aromatic content, sulphur level and VI are parameters used by the American Petroleum Institute (API) to categorize the base oils as Group II or Group III. The performance of additives in these Groups II and III base stocks differs from that in Group I base stocks. In addition, different processes used by different manufacturers will not only create different base stock oxidative stability and solvency from that of Group I base stocks, it will also create differences between Group II base stocks and between Groups II and III base stocks. Several different base stocks have been examined using methods including mass spectrometry and aniline point. Variations in properties, such as aromatic content, cycloparaffinic content and aniline point, appear to relate to differences in oxidation stability and solvency. With the improved response of Groups II/III base stocks to antioxidants, a performance level of 10,000 hours or greater in the ASTM D 943 is common. This necessitates addition of specific antioxidants which result in extended oxidation performance but lead in some cases to the formation of insoluble degradation products in Group II/III base stocks, and more so in Group I base stocks. Phenolic‐ containing and phenolic‐free antioxidant systems have been identified that allow for extended oxidation stability in a wide range of Group II base stocks without sludge formation in either Group I, II or III base stocks.

This paper aims to discuss that a WC/Co-Cr alloy coating was applied to the surface of H13 steel by laser cladding.

The oxidation behavior of the WC/Co-Cr alloy coating at 600°C was investigated by comparing it with the performance of the steel substrate to better understand the thermal stability of H13 steel.

The results showed that the WC/Co-Cr alloy coating exhibited better high-temperature oxidation resistance and thermal stability than did uncoated H13 steel. The coated H13 steel had a lower mass gain rate and higher microhardness than did the substrate after different oxidation times.

The WC/Co-Cr alloy coating was composed of e-Co, CW3, Co6W6C, Cr23C6 and Cr7C3; this mixture offered good thermal stability and better high-temperature oxidation resistance.

The purpose of this study is to evaluate the potentials of nano-additives in enhancement of oxidation and thermal stability of biolubricants thereby, improving the resistance of dispersed nanolubricants to thermal degradation under elevated temperature.

This study evaluates the oxidation stability and tribological performance of nano-enhanced biolubricants. Graphene and maghemite nanoparticles at 0.1% volume concentration were dispersed into coconut oil. Oxidation stability was analysed using a thermal analyser to understand the effect of nano-additives on thermal degradation of lubricants under increasing temperature. In addition, tribological performance and viscosity of the tested lubricants were evaluated using a four-ball friction tester and viscometer according to American Society for Testing and Materials standards.

The results reveal that the oxidation stability of biolubricants dispersed with nano-additives improves due to delayed thermal degradation. The nano-enhanced biolubricants’ oxidation onset temperature was delayed by 18.75 °C and 37.5 °C, respectively, for maghemite (MGCO) and graphene (XGCO) nanolubricants. This improvement imparts the performance viscosity and tribological performance positively. For graphene-enhanced nanolubricant, 10.4% and 5.6% were reduced, respectively, in coefficient of friction (COF)and wear scar diameter (WSD), whereas 3.43% and 4.3% reduction in COF and WSD, respectively, for maghemite-enhanced nanolubricant compared with coconut oil. The viscosity index of nanolubricants was augmented by 7.36% and 13.85%, respectively, for maghemite and graphene nanolubricants.

The excellent performance of nanolubricants makes them suitable candidate as sustainable lubricants for machining with regard to environmental benefits and energy saving.

The effect of graphene and maghemite nanoparticles on the oxidation stability and tribological performance of biolubricants has been investigated. It is an original work and yet to be published elsewhere.

The purpose of this paper is to study a novel Mannich adduct of benztriazole-containing diphenylamine (coded as BD) and its anti-oxidation properties as an additive in two typical synthetic ester-based oils.

The anti-oxidation properties in two typical synthetic ester-based oils were evaluated in detail, using rotating pressure vessel oxidation test. The tribological properties of BD in synthetic ester-based oil (A51) were also tested with Optimal SRV-I oscillating friction and wear tester at atmosphere.

The results of tests demonstrated that the novel BD compound is, indeed, a high-performance anti-oxidation additive that was able to remarkably improve the oxidation stability of synthetic ester-based oils, when it was added at only 0.5 per cent concentration and compared with the base oils containing 0.5 per cent of the commercial available antioxidant additives such as 2, 6-di-tert-butyl-4-methylphenol and octyl-butyl diphenylamine. A plausible mechanism of exceptional synergistic anti-oxidation was proposed.

This paper first investigated the anti-oxidation properties and mechanisms of the compound with the structure of BD, which can be very useful and would promote the application of BD antioxidant in the lubricant industry.

The purpose of this paper is to evaluate the optimization of high hydrostatic pressure (HHP) processing for the microbial inactivation on low-sodium sliced vacuum-packaged turkey breast supplemented with a natural antimicrobial compound (carvacrol).

A response surface methodology was used to model and describe the effects of different pressures (200–650 MPa) and holding times (30–300 s) during HHP processing of low-salt ready-to-eat turkey breast supplemented with 200 mg/kg of carvacrol on survival of the target pathogen (Listeria sp.) and spoilage microflora and on the quality attributes, including pH, syneresis, CIE color and lipid oxidation.

The HHP parameters influenced (p<0.05) the lethality rates and syneresis but did not affect the pH values and lipid oxidation of the products evaluated. According to the required performance criteria for Listeria post-lethality treatment, a treatment at 600 MPa/180 s (at 25°C) appears to be suitable for the studied low-sodium product. The HHP bacterial inactivation effects can notably be potentiated via the presence of carvacrol, and is useful at sensory acceptable sub-inhibitory levels.

This study shows that combined HHP plus additives may produce similar safety and shelf-life extension effects with mild HHP treatments, creating a global increase in the quality of HHP-processed food in addition to reducing costs on equipment maintenance and increasing industry productivity.

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 objective of this study was to elaborate and characterize formulations of type mortadella bologna in an industrial unit.

Two formulations (Formulation 1 – F1 and Formulation 2 – F2) were characterized at a storage stability of 22 ºC for physicochemical (pH, a_w, moisture, protein, fat and lipid oxidation: TBARs and peroxide index, nitrite/nitrate, texture and thermal analysis: TG), sensory (acceptability), microbiological (Clostridium reducing sulfite, Streptococcus, Salmonella sp., mesophilic and coliform thermosensitive) and histological (organization and tissue distribution) characteristics.

In relation to the water activity (a_w), the formulation F2 presented a value of 0.925 as well as the lower TBARs (0.19 mg MDA/kg) and greater hardness (3945.47 gf), 85% acceptance index and greater mass loss by thermal analysis after 60 days of storage. The multivariate analysis showed that the hardness presents negative correlation in relation cohesiveness, resilience and a_w. There is also a strong positive correlation of the cohesiveness in relation to the resilience and a_w. In addition, moisture has a high positive correlation with TBARs, peroxide index, a_w, L* and texture parameters (adhesiveness, cohesiveness and resilience).

Therefore, the importance of the elaboration process of emulsified meat products was emphasized, aiming to add value and guarantee food safety, taking into account the current legal aspects.