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1.
J Sci Food Agric ; 104(5): 3039-3046, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38057148

RESUMEN

BACKGROUND: Postmortem muscle moisture loss leads to a decrease in carcass weight and can adversely impact overall meat quality. Therefore, it is critical to investigate water holding capacity (WHC) to enhance meat quality. Current research has primarily focused on examining the correlation between signaling molecules and meat quality in relation to the glycolysis effect on muscle WHC. But there exists a significant knowledge gap regarding the mechanism of WHC in Jersey cattle-yak meat. RESULTS: Jersey cattle-yak meat pH decreased and then increased during postmortem aging. Lactate content, cooking loss, pressing loss, drip loss and centrifuging loss of Jersey cattle-yak meat increased and then decreased during postmortem aging. The glycogen content of Jersey cattle-yak meat was significantly higher than that of yak meat at 6-120 h, being 8.40% higher than that of yak meat at 120 h. The activity of key glycolytic enzymes hexokinase (HK), pyruvate kinase (PK), phosphofructokinase (PFK) and lactate dehydrogenase (LDH) in Jersey cattle-yak meat was lower than that in yak meat. Correlation analysis showed that Jersey cattle-yak meat WHC was positively correlated with the activity of HK, PK, PFK and LDH. CONCLUSIONS: The WHC of Jersey cattle-yak meat was higher than that of Gannan yak meat, and it was significantly positively correlated with the activity of key enzymes of the glycolytic signaling pathway. Therefore, the glycolysis rate can be reduced by inhibiting enzyme activity to improve Jersey cattle-yak meat WHC and meat quality. © 2023 Society of Chemical Industry.


Asunto(s)
Culinaria , Agua , Animales , Bovinos , Agua/análisis , Carne/análisis , Glucólisis , Músculo Esquelético/química
2.
Molecules ; 28(20)2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37894496

RESUMEN

Matcha is a powdered green tea obtained from the Camellia sinensis L. plant intended for both "hot" and "cold" consumption. It is a rich source of bioactive ingredients, thanks to which it has strong antioxidant properties. In this research, an organoleptic evaluation was carried out, and the physical characteristics (i.e., instrumental color measurement (L*a*b*), water activity, water solubility index (WSI), water holding capacity (WHC) of 10 powdered Matcha green teas, and in the 2.5% Matcha water solutions, pH, °Brix and osmolality were tested. Also, the content of phenolic ingredients, i.e., selected phenolic acids, flavonoids and total polyphenols, was assessed. The content of chlorophyll, vitamin C and antioxidant potential were also examined. Matcha M-4 was used to design two functional model beverages, in the form of ready-to-use powdered drinks, consisting of Matcha green tea, protein preparations, inulin, maltodextrin and sugar. The obtained powdered drink, when dissolved in the preferred liquid (water, milk, juice), is regenerative, high-protein and rich in bioactive ingredients from the Matcha drink, with prebiotic properties derived from the added inulin. The beverage is also characterized by low osmolality. It can be recommended as a regenerating beverage for a wide group of consumers, athletes and people with deficiencies, among others protein, and elderly people, as well as in the prevention and supportive treatment of bone and joint tissue diseases.


Asunto(s)
Camellia sinensis , , Humanos , Anciano , Té/química , Antioxidantes/análisis , Inulina , Bebidas/análisis , Camellia sinensis/química , Agua
3.
J Sci Food Agric ; 103(2): 514-523, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36468614

RESUMEN

BACKGROUND: Adenosine monophosphate-activated protein kinase (AMPK) is instrumental in the initiation of early postmortem glycolysis and the advent of pale, soft, and exudative (PSE) meat when cellular energy is altered. However, conflicting studies show that AMPK activation without corresponding energy level changes in PSE meat challenges this long-held notion. Here, we examined the effects of reactive oxygen species (ROS)-mediated oxidative stress on AMPK activation in the context of glycolysis, protein solubility, and water-holding capacity (WHC) in the postmortem yak longissimus dorsi (LD) muscle. Further, we explored the mechanisms underlying these effects. RESULTS: Hydrogen peroxide (H2 O2 ) significantly augmented the degree of oxidative stress, increasing the production of ROS and malondialdehyde excessive production and reducing the activity of the anti-oxidants superoxide dismutase and glutathione peroxidase. In turn, oxidative stress dramatically promoted AMPK activation and glycolysis by increasing glycogen depletion and promoting hexokinase and phosphofructokinase activity. Subsequently, lactic acid accumulation increased, leading to a rapid decline in pH, which aggravated protein solubility degree and centrifugal loss in the early postmortem yak LD muscle. Importantly, these changes caused by oxidative stress were eliminated by the AMPK inhibitor. Mechanistically, oxidative stress elevated calcium ion (Ca2+ ) levels, which mobilized calcium/calmodulin-dependent protein kinase ß (CaMKKß) and AMPK. Rescue experiments confirmed that the increases were attenuated using Ca2+ and CaMKKß chelators, respectively. CONCLUSION: These results indicated that oxidative stress caused by ROS hastened early-stage postmortem glycolysis and reduced the WHC of yak meat. These effects were likely mediated by the alternative and energy-independent CaMKKß/AMPK signaling pathway. © 2022 Society of Chemical Industry.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina , Bovinos , Animales , Especies Reactivas de Oxígeno , Proteínas Quinasas Activadas por AMP/genética , Calcio , Estrés Oxidativo , Glucólisis , Transducción de Señal
4.
Saudi J Biol Sci ; 29(5): 3432-3439, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35844428

RESUMEN

The impact of yellow pumpkin powder (YP) substitution (5, 10, and 15%) on wheat flour's physico-functional, pasting, gel texture, and dough rheology was studied. Moreover, the nutritional, organoleptic properties and bioactivity of the composite pan and pita bread were evaluated. An improved water holding capacity was noticed for the blended flour than for control. The pasting parameters were declined significantly (p < 0.05) with increasing YP. Composite flours presented a softer gel texture in the presence of YP. Reduced water absorption, increased dough development time, and lower stability for combined flour dough. The bread with YP depicted increased protein, fat, fiber, and mineral contents, while a reduced volume and specific volume were noticed for pan bread. YP incorporated 5% and did not compromise pan and pita bread's color and overall acceptability. Additionally, composite bread depicted higher total phenolics with enhanced antioxidant activities at the higher substitution of YP.

5.
Foods ; 11(9)2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35563998

RESUMEN

The specifics of meat production from free-ranging animals include the killing of animals in the wild with firearms. This type of uncontrolled killing sometimes leads to the phenomenon that the game does not die immediately but after a certain time from the shot to death, which may ultimately affect the quality of the meat. During one hunting year on free-ranging red deer (Cervus elaphus) (RD), roe deer (Capreolus capreolus) (RoD), and wild boar (Sus scrofa) (WB), the effect of time from shot to death on final pH, water-holding capacity (WHC), water content, and colour (L*, a*, b*) was investigated. All analyses were performed on Musculus biceps femoris (BF). After shooting, the animals were divided into two categories (A = time from shot to death ≤ 1 min; B = time from shot to death > 1 min). In RD, group B had significantly lower (p < 0.05) water content. In RoD, group B had significantly lower (p < 0.05) values of L* and b*. In WB, group B had significantly lower (p < 0.05) L* value and significantly higher (p < 0.05) pH value. The study proves that in BF of the three studied game species, the time extension from shot to death significantly affects the final water content values in RD, L* and b* in RoD and pH and L * in WB.

6.
J Dairy Res ; : 1-7, 2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35388774

RESUMEN

We investigated the use of near-infrared spectroscopy (NIR) for measuring water-holding capacity (WHC) in fermented milk. Increased WHC ensures improved texture and decreased syneresis in fermented dairy products and also improves cheese yield. NIR combined with partial least-squares-discriminant analysis (PLS-DA) was found to be a promising rapid and non-invasive method with no pretreatment of the samples for prediction of WHC in fermented milk samples. Analysis of the chemical bonds in the region 10 700-4500 cm-1 (935-2200 nm) of the electromagnetic spectrum was able to distinguish between samples with high vs. low WHC. This technique was successfully used to screen different strains of lactic acid bacteria for their ability to provide fermented milk with increased WHC, which is of great importance for use in various dairy products.

7.
Foods ; 11(3)2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35159481

RESUMEN

This study investigates the effects of cathepsins on the gel strength and water-holding capacity (WHC) of myofibrillar protein gels from bighead carp (Aristichthys nobilis) under a hydroxyl radical-generation oxidizing system. The myofibrillar proteins were divided into control group (with cathepsins) and E64 group (without cathepsins). The changes of cathepsin B and cathepsin L activities, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), protein oxidation (total sulfhydryl and carbonyl contents), and chemical interactions (nonspecific association, ionic bonds, hydrogen bonds, hydrophobic interactions, and disulfides) of myofibrillar protein and gels, as well as the gel strength and WHC of two groups under 0-100 mM H2O2, were measured. The results indicated that mild oxidation (10 mM H2O2) made a better gel strength and WHC. Cathepsin B and L activities decreased with increasing H2O2 concentrations but their effects on myofibrillar protein degradation still existed during 0.1-50 mM H2O2, which was expressed by higher carbonyl contents and ionic bonds at 0.1 and 50 mM H2O2, higher total sulfhydryl contents at 0 mM H2O2, and a lower intensity of MHC and actin of the control group than the E64 group. Besides more protein degradation, cathepsin proteolysis also resulted in lower gel strength and WHC in control gels than E64 gels under mild oxidation, which could be explained by lower hydrophobic interaction and moderate disulfides bonds between gel protein molecules of control gels.

8.
Meat Sci ; 176: 108486, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33711679

RESUMEN

The purpose of this study was to develop an in situ model for dark cutting beef. Iodoacetic acid (IAA) was injected at different concentrations (0, 0.625, 1.25, 2.5, 3.75, 5, or 10 µmol/g of muscle) into pre-rigor bovine longissimus thoracis et lumborum (LTL) muscle samples, and pH and color were evaluated over a 48 h period. Injection of IAA blunted muscle pH decline and lowered lightness (L*), redness (a*), and yellowness (b*) values (P ≤ 0.05) in a concentration dependent fashion. In a follow-up study, LTL muscle samples were injected with 5 µmol IAA/g of muscle to test whether IAA maintains its effect over a 336 h post-mortem storage period. In addition to inhibiting pH decline and decreasing color values, IAA increased LTL muscle water holding capacity (WHC) and firmness (P ≤ 0.05) throughout the 336 h post-mortem storage period. Collectively, these data suggest that pre-rigor injection of IAA generates beef with dark cutting-like characteristics.


Asunto(s)
Ácido Yodoacético/administración & dosificación , Carne Roja/análisis , Animales , Bovinos , Color , Inhibidores Enzimáticos/administración & dosificación , Concentración de Iones de Hidrógeno , Masculino , Músculo Esquelético/química
9.
Food Chem ; 345: 128849, 2021 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-33601660

RESUMEN

The study was to investigate the role of direct current magnetic field (DC-MF) for water-holding capacity (WHC) of myofibrillar protein gels and to understand potential mechanisms. Samples were subjected to DC-MF with different intensities (3.5, 3.8, 9.5 and 10.4 mT), and DC-MF treatment significantly improved WHC compared with control (46.09%), reaching the maximum value of 50.36% at 3.8 mT. The main reason for the increase in WHC might be that DC-MF modified the protein structure via unfolding, re-crosslinking and aggregation of proteins, which was supported by the increased intensity of tyrosine, aliphatic and tryptophan residues, and reduced reactive sulfhydryl (2.97 to 1.94). And the re-crosslinking between molecules was maintained mainly through hydrophobic interactions and disulfide bonds. Besides, DC-MF treatment helped to generate a relatively loose and uniform microstructure to trap more water as shown by electron microscope image, which was consistent with the highest WHC at 3.8 mT.


Asunto(s)
Geles/química , Proteínas Musculares/química , Agua/química , Animales , Disulfuros/química , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica , Nefelometría y Turbidimetría , Resonancia Magnética Nuclear Biomolecular , Agregado de Proteínas , Solubilidad , Porcinos
10.
Ces med. vet. zootec ; 16(1): 8-28, ene.-abr. 2021. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1350439

RESUMEN

Resumen Las propiedades fisicoquímicas como terneza, color, jugosidad, sabor, marmoleo, pH y capacidad de retención de agua, son consideradas como los atributos que tienen mayor importancia en la calidad de la carne. El manejo post mortem influye en el funcionamiento del sistema proteolítico de las enzimas µ-calpaínas y calpastatinas, que están codificadas por los genes CAPN1 y CAST, respectivamente. Esta revisión muestra las asociaciones de los polimorfismos CAPN1 y CAST con el fin de explicar las propiedades fisicoquímicas antes mencionadas, que determinan las características relacionadas con la calidad de la carne. Existen polimorfismos de CAPN1 y CAST asociados a propiedades fisicoquímicas particulares de la carne, pero no todos los polimorfismos se asocian con las propiedades mencionadas. La actividad del sistema proteolítico de las enzimas varía según el manejo peri y post mortem. La presencia o ausencia de un polimorfismo varía entre razas. Por consiguiente, las asociaciones de polimorfismos de nucleótido simple con las propiedades fisicoquímicas de la carne mencionadas en esta revisión podrían ayudar a mejorar los indicadores de calidad de la carne bovina.


Abstract Physicochemical properties such as tenderness, color, juiciness, flavor, marbling, pH and water retention capacity, are considered the most important attributes in the meat quality. Posmortem management influences the functioning of the proteolytic system of the enzymes calpains and calpastatins, which are encoded by CAPN1 and CAST genes, respectively. This review displays the associations of CAPN1 and CAST polymorphisms in order to explain the aforementioned physicochemical properties, which determine the characteristics relate to the beef quality. There are CAPN1 and CAST polymorphisms associated with particular physicochemical properties of meat, but not all polymorphisms are associated with the mentioned properties. The activity of enzymes proteolytic system varies according to peri and posmortem management. The presence or absence of a polymorphism varies between races. Therefore, the associations of single nucleotide polymorphisms with the physicochemical properties of meat mentioned in this review could help to improve the quality indicators of beef.


Resumo Propriedades físico-químicas como maciez, cor, suculência, sabor, marmorização, pH e capacidade de retenção da água, são consideradas os atributos mais importantes na qualidade da carne. O manejo pós-morte influencia o funcionamento do sistema proteolítico das enzimas calpaína e calpastatina, que são codificadas pelos genes CAPN1 e CAST, respectivamente. Esta revisão mostra as associações dos polimorfismos CAPN1 e CAST para explicar as propriedades físico-químicas citadas, que determinam as características relacionadas à qualidade da carne. Existem polimorfismos CAPN1 e CAST associados a propriedades físico-químicas específicas da carne, mas nem todos os polimorfismos estão associados às propriedades mencionadas. A atividade das enzimas do sistema proteolítico varia de acordo com o manejo peri e pos-mortem. A presença ou ausência de um polimorfismo varia entre as raças. Portanto, as associações de polimorfismos de nucleotídeo único com as propriedades físico-químicas da carne mencionadas nesta revisão poderiam ajudar a melhorar os indicadores de qualidade da carne bovina.

11.
Food Chem ; 344: 128587, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33191014

RESUMEN

This work explored the effects of protein unfolding and cross-linking induced by lipid oxidation (linoleic acid, OLA) on the gel water-holding capacity (WHC) of beef myofibrillar proteins (MP). Medium concentration of OLA (≤6 mM) caused the increase of gel WHC from 55.2% to 65.1%, while relative high OLA concentration (>6 mM) decreased the gel WHC. When the OLA concentrations increased from 0 to 10 mM, the population of immobile water of gel decreased from 92.91% to 78.97%, whereas that of free water increased from 6.13% to 19.80%, suggesting that OLA treatment regardless concentration was harmful for gel WHC. However, medium OLA concentrations (≤6 mM) caused the shifting of α-helixes to ß-sheets in MP gel, exerting positive effect on gel WHC. Protein unfolding and cross-linking jointly determined the increased gel WHC at moderate oxidative modification. Additionally, the protein aggregation at high OLA concentration resulted in decreased gel WHC.


Asunto(s)
Geles/química , Peroxidación de Lípido , Proteínas Musculares/química , Agua/química , Animales , Bovinos , Interacciones Hidrofóbicas e Hidrofílicas , Ácido Linoleico/química , Proteínas Musculares/metabolismo , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Desplegamiento Proteico
12.
J Food Sci ; 85(10): 3214-3219, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32857865

RESUMEN

In recent years, hydrocolloids have been used extensively as enhancers in dough products. However, studies on the effect of hydrophilic polymers on wheat gluten (WG) within the dough are scarce. In the present study, poly-γ-glutamic acid (γ-PGA), a new and healthy food additive, was added to the WG to investigate its effect on hydration, rheological properties, and structures of WG. Results showed that with the addition of γ-PGA, the water-holding capacity (WHC) of WG and the content of bound water increased, whereas the content of immobilized water decreased. In addition, γ-PGA changed the rheological properties of WG. The elastic properties of WG gradually weakened and the viscous properties gradually increased. Furthermore, scanning electron microscopy (SEM) results showed that with the addition of γ-PGA, the structure of the WG network became more uniform and the pore size was smaller. A change also occurred in the secondary structure of WG, in which the α-helix content was significantly reduced while the contents of ß-turn angles were significantly increased, thereby suggesting that γ-PGA not only functions as a filler in the WG system, but also interacts with WG. From the present study, we conclude that γ-PGA can interact with WG and water to change the WG secondary structure. γ-PGA can also restrict moisture migration and enhance the WHC of WG, thereby changing the WG microstructure and improving its functional properties. This condition provides the basis for γ-PGA to be recommended as WG enhancer for addition in WG-containing products such as bread, seitan (meat replacement), and others. PRACTICAL APPLICATION: WG performance plays a key role in the quality of flour products. Thus, many studies have been conducted to improve the WG quality to produce highly popular flour products. The results of this study showed that γ-PGA can interact with WG and water, and had a good effect on improving the WHC of WG, which means that γ-PGA has potential usefulness in improving the quality of WG and WG-containing products such as bread, seitan (meat replacement), and others.


Asunto(s)
Glútenes/química , Ácido Poliglutámico/análogos & derivados , Triticum/química , Agua/química , Harina/análisis , Aditivos Alimentarios/química , Ácido Poliglutámico/química , Reología , Viscosidad
13.
Mater Sci Eng C Mater Biol Appl ; 110: 110619, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32204063

RESUMEN

Bacterial cellulose (BC) hydrogels are among the most efficient materials already being used for the treatment of complex wounds. The moist environment provided by the BC dressing is a key feature assuring efficient wound recovery. Improving the dressings´ moisture-holding ability facilitates its application and leads to an economically preferable extended wear time. To produce materials with reduced moisture loss, BC dressings were impregnated with a secondary hydrophilic component: alginate. The feasibility of an industrial fabrication of this composite was evaluated on pilot scale equipment. It was shown that the procedure can easily be scaled up without significantly increasing the manufacturing time. The resultant composite possessed improved water-retention properties, providing a smooth dressing exchange as demonstrated by a wound-imitating model. The new materials were moreover shown to be compatible with an antimicrobially active compound, which assures their efficiency in the treatment of highly colonized wounds.


Asunto(s)
Alginatos/química , Antibacterianos/química , Bacterias/química , Vendajes , Celulosa/química , Línea Celular Transformada , Humanos , Ensayo de Materiales
14.
Poult Sci ; 99(2): 1225-1231, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32036971

RESUMEN

This study was undertaken to assess the effect of various levels of intramuscular fat (IMF: <0.5%, 0.5-0.99%, 1.0-1.49%, 1.5-1.99%, 2.0-2.49%, and >2.5%) on the physical meat quality of partridge. Physical characteristics such as moisture, pH, shear force, water-holding capacity (WHC), and color, along with IMF, were measured on 414 partridges (pectoral muscle). In this study, partridge meat was described as a kind of tender and moderately juicy meat with a nice color. Additionally, tenderness was significantly different between IMF < 0.5% and IMF > 0.5% levels (P < 0.01). IMF >0.5% also obtained higher value of WHC than IMF <0.5% although the difference was statistically nonsignificant. IMF levels did not affect pH or color. The results showed that IMF content was not significantly correlated with physical meat quality. However, in terms of eating experience, the minimum IMF level for better meat quality for consumer was 0.5%. Pearson correlation coefficients indicated that IMF content had significant negative correlations with moisture content but not with pH (r = -0.066), shear force (r = -0.072), WHC (r = 0.085), or color (L*(r = -0.049), a*(r = -0.028) and b*(r = 0.045)). Besides, meat pH had significant negative correlations with WHC (r = -0.036; P < 0.01) and lightness (L*) (r = -0.292; P < 0.01). Consequently, we consider pH to be one of the most important factors in evaluating meat quality of partridge.


Asunto(s)
Tejido Adiposo , Carne/normas , Codorniz , Animales , Color , Concentración de Iones de Hidrógeno , Carne/análisis , Músculo Esquelético , Resistencia al Corte , Agua
15.
Biochem Biophys Res Commun ; 505(2): 612-617, 2018 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-30278886

RESUMEN

Caffeic acid is a natural phytochemical structurally similar to other cinnamic acids. In this study we found caffeic acid (CA) but not ferulic, sinapic or cinnamic acids inhibited proliferation of hepatocellular carcinoma cells (HCC) and reduced cell numbers by inducing apoptosis. Only transient exposure to CA was required for these lethal effects that are associated with disruption of mitochondrial membrane potential and induction of reactive oxygen species. By comparison, primary hepatocytes resisted CA toxicity for nearly 48 h, consistent with selective sensitivity of HCC to CA. These results support use of CA as an anti-tumor agent to inhibit HCC, especially if delivered by locoregional catheterization in an embolization procedure.


Asunto(s)
Antineoplásicos/farmacología , Ácidos Cafeicos/farmacología , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Animales , Antineoplásicos/uso terapéutico , Antineoplásicos/toxicidad , Ácidos Cafeicos/uso terapéutico , Ácidos Cafeicos/toxicidad , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Neoplasias Hepáticas Experimentales/patología , Marmota , Potencial de la Membrana Mitocondrial/efectos de los fármacos
16.
Meat Sci ; 139: 91-96, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29413682

RESUMEN

Effects of rigor cross-bridge attachment on water holding in PSE-like conditions were investigated. A new model using permeabilised/skinned porcine longissimus thoracis et lumborum muscle fibres was established to study effects of varied pH, temperature and the presence of rigor bonds on the muscle fibre structure. Preparations were exposed during 30min to different temperatures (22 and 38°C) and pH (7.0 and 5.5) in relaxed and rigor states, followed by evaluation of active force and filament lattice spacing (using small angle X-ray scattering) at standard pH (7.0) and temperature (22°C) conditions. A significant reduction of active force and filament spacing was observed after treatment in rigor at denaturing (38°C, pH5.5) conditions. The present study show that rigor bond attachment under denaturing conditions leads to a compressed interfilamental space, loss of sarcomeric water and affected contractile function.


Asunto(s)
Músculo Esquelético/química , Carne Roja/análisis , Sarcómeros/química , Agua/química , Animales , Concentración de Iones de Hidrógeno , Contracción Muscular , Fibras Musculares Esqueléticas/ultraestructura , Rigor Mortis , Sus scrofa , Temperatura
17.
Contact Dermatitis ; 77(1): 25-34, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28300294

RESUMEN

BACKGROUND: Many skin diseases are associated with either increases or decreases in lamellar body secretion, or dysfunctional lamellar bodies. Consequently, diseased skin is characterized by reduced barrier function and altered lipid composition and organization. Human skin is commonly evaluated in vivo with non-invasive biophysical techniques. The dynamic functions of the skin are evaluated with repeat measurements such as the sorption-desorption test (SDT). OBJECTIVES: The aim of this study was to evaluate in vivo skin hydration-dehydration kinetics after treatment with a lipid system that mimics the morphology, structure and composition of lamellar bodies in both healthy and irritated human skin. METHODS: A patch with an aqueous solution of 2% sodium lauryl sulfate (SLS) was used to irritate the skin of the volunteers. The SDT was performed with the CM 820 corneometer. RESULTS: After treatment with this system, both healthy and SLS-irritated skin increased their ability to retain water and to release water slowly during the desorption phase. CONCLUSIONS: Treatment with this system seems to reinforce the barrier function in both healthy and SLS-irritated human skin. Therefore, the present study provides evidence that this system could be of interest for developing future treatments for protecting and repairing the skin.


Asunto(s)
Dermatitis Irritante/diagnóstico , Absorción Cutánea , Pruebas Cutáneas/métodos , Agua/metabolismo , Adulto , Epidermis/metabolismo , Femenino , Humanos , Irritantes/administración & dosificación , Metabolismo de los Lípidos , Persona de Mediana Edad , Fenómenos Fisiológicos de la Piel
18.
Food Chem ; 223: 96-103, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28069130

RESUMEN

We wanted to clarify whether gel properties can be affected by in vivo or in vitro myofibrillar protein oxidation and, thus, to provide relevant information and a scientific foundation for the processing of gel products. To accomplish this, we measured the changes in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), total disulfide (SS) content, surface hydrophobicity (So-ANS), carbonyl content, and gel texture and water-holding capacity (WHC) of isolated myofibrillar protein from bighead carp fillets during frozen storage and under different H2O2 concentrations, which were used to represent in vivo and in vitro conditions, respectively. The results indicated that a certain range in content of disulfide crosslinks (0.91mol/105g protein) would promote gel hardness. Mild protein oxidation caused by a certain degree of frozen storage and hydroxyl radicals can promote gel texture and WHC. Based on those results, freezing bighead carp for a certain period can be used to produce gel products.


Asunto(s)
Carpas , Proteínas de Peces/metabolismo , Congelación , Radical Hidroxilo/metabolismo , Miofibrillas/metabolismo , Animales , Electroforesis en Gel de Poliacrilamida/métodos , Proteínas de Peces/análisis , Conservación de Alimentos/métodos , Geles , Peróxido de Hidrógeno/toxicidad , Radical Hidroxilo/análisis , Miofibrillas/química , Miofibrillas/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos
19.
Food Sci Biotechnol ; 26(3): 549-556, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-30263578

RESUMEN

The effects of l-lysine (l-Lys) on the water holding capacity (WHC) and texture of actomyosin (AM) gel and the possible mechanisms were investigated. l-Lys increased the WHC and hardness of the AM gel. These effects may be related to the even and continuous microstructure of the gel according to the scanning electron microscopy analysis. Furthermore, l-Lys increased the surface hydrophobic residues and the reactive sulfhydryl groups. l-Lys decreased the storage modulus at the first transition temperature but increased it at the second transition temperature and the third transition enthalpy. These results suggested that l-Lys varied the thermal behaviors and the microstructure of the AM gel by increasing the surface hydrophobicity and reactive sulfhydryl groups, ultimately contributing to the increased WHC and hardness. The changes in pH did not fully explain the results from the present study. The results were useful for understanding previous findings and may serve as a reference for the preparation of reduced-sodium and phosphate-free meat products.

20.
J Food Sci Technol ; 53(10): 3761-3769, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28017991

RESUMEN

In this paper the effects of frozen storage time, xanthan gum and rate of freezing on frozen sweet dough properties and unfermented bread quality was investigated. Results revealed that the water holding capacity, WHC, K1 (stress decay rate) and K2 (residual stress at the end of the stress relaxation experiment) values of frozen dough decreased with increasing frozen storage time and decreasing freezing rate; while the lowest values for these parameters were obtained for samples without xanthan gum. The amount of unfreezable water increased and freezable water decreased with addition of xanthan gum. Glass transition temperature for fresh or frozen sweet were around -37 and -39 °C, respectively. Addition of xanthan gum increased the glass transition temperature of fresh and fozen sweet dough. Firmness and gumminess of sweet bread increased during frozen storage which led to lower specific volume of frozen sweet bread. Increasing freezing rate and addition of xanthan gum to dough formulation improved the texture and specific volume of the final bread.

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