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espanolEn un intento por regular positivamente la calidad de la carne a baja concentracion de NaCl, el presente estudio investigo como influye la introduccion de L-histidina (L-his) en la fosforilacion post-mortem de la proteina del musculo de la pechuga de pollo curada durante 16 horas a 1% de NaCl despues de 90 minutos post-mortem. Los resultados de este procedimiento permitieron verificar la presencia de 633 fosfoproteinas diferentes (﹥1.2 veces) inducidas por la introduccion de L-his durante la salazon; la mayoria de las mismas estaba implicada en la glucolisis, la via de senalizacion del calcio y la contraccion muscular. Ademas, se comprobo que las principales proteinas expresadas diferencialmente (DEPs) asociadas con la contraccion muscular fueron la miosina, la actina, la titina, la troponina C (TnC), la cadena ligera de miosina quinasa (MLCK) y la γ-fosforilasa quinasa (γ-PHK). Al respecto, tras el tratamiento con L-hisse se obtuvo una regulacion ventajosa de la fosforilacion de la fosfoglucomutasa-1, la fructosa-1,6-bisfosfatasa y el componente E1 de la enzima piruvato deshidrogenasa en el metabolismo glucolitico. EnglishIn an attempt to positively regulate meat quality at low NaCl concentration, the influence of L-histidine (L-his) introduction on the postmortem phosphorylation of chicken breast muscle protein that had been cured for 16 h at 1% NaCl was investigated at 90 min postmortem in the present study. The 633 different phosphoproteins (﹥1.2-fold) induced by L-his introduction during salting were identified, and a majority of these proteins were involved in glycolysis, calcium signalling pathway and muscle contraction. Myosin, actin, titin, troponin C (TnC), myosin light-chain kinase (MLCK) and γ-phosphorylase kinase (γ-PHK) were the main differentially expressed proteins (DEPs) that were associated with muscle contraction. An advantageous regulation of phosphoglucomutase-1 phosphorylation, fructose-1,6-bisphosphatase and pyruvate dehydrogenase E1 component was obtained in glycolytic metabolism after treatment with L-his.

The present study was conducted to explore the impact of novel water–oil mixed frying and traditional oil frying methods on the soybean oil quality and formation of trans fatty acids (TFAs) and heterocyclic amines (HCAs) in fried duck breast and skin during 60 frying cycles. The acid value of the soybean oil was 2.10 mg/g using the traditional oil frying and 1.08 mg/g using water–oil mixed frying at the 60th frying cycle. The peroxide value of the water–oil mixed fried soybean oil was significantly lower than that of the traditional frying method. Water–oil mixed frying delayed the formation of TFAs in the soybean oil. The traditionally oil fried skin showed increased TFAs (9tC16:1) content from 0.17 to 0.22 mg/g (29.4% increase), while those of the water–oil mixed fried samples increased from 0.16 to 0.20 mg/g (25.00% increase) compared to control. Harman, Norharman and AαC were detected in all the fried samples and PhIP was observed after the 20th frying cycle, while MeAαC was formed only at the 60th frying cycle in traditional fried duck breast. Therefore, it is concluded that the water–oil mixed frying method is more suitable to improve the quality and safety of fried duck skin and breast meat.

The present study was conducted to explore the impact of novel water-oil mixed frying and traditional oil frying methods on the soybean oil quality and formation of

Physical tenderization technologies for beef have been of particular interest to the meat industry. Here a novel tenderization technology by mechanical resonance vibration was proposed. The fundamental natural frequency (NF

Roasting meat involves simultaneous heat and mass transfer, colour and flavour development and the formation of hazardous chemicals. The objectives of this study were to evaluate the effects of temperature and time on colour, 3,4-benzo(a)pyrene (BaP) and heterocyclic aromatic amines (HCAs) in roast duck skin during forced hot-air drying at less than 130 &deg, C. The results showed that surface and internal temperatures of duck carcasses increased with drying time, rising to 111.9 and 83.7 &deg, C, respectively. The curves of water activity (aw) and red index (a*) intersected at 50 min because of the decrease in aw and the increase in a* on the skin with drying time. The drastic decline in aw promoted colour development on the duck surface. BaP and carcinogenic HCAs were not detected in hot-air drying ducks, convincing us that the mild cooking method under forced hot-air drying could effectively reduce or eliminate the risk of certain human cancers.

To obtain healthier meat products with reduced Na content, the salt substitute containing L-histidine and L-lysine was compared with NaCl in the hydrolysis and oxidation of protein and lipids of dry-salted fish during processing. Compared with NaCl-treated fish (S-F), salt substitute treated fish (SS-F) had a lower Na content, higher moisture content and lower hardness. Sensory analysis showed that salt substitute didn't affect the acceptability of salted fish. The free fatty acids of SS-F treated fish had a slight tendency toward lipolysis at the end of processing. Additionally, the conjugated diene value, lipoxygenase activity and malondialdehyde value were lower in the ventral and dorsal muscles for the SS-F treatment. Meanwhile, the protein carbonyls and thiol groups were significantly decreased as cathepsin B and L activities and FAA content were increased in the ventral and dorsal muscles for the SS-F treatment. L-Histidine and L-lysine accelerated the hydrolysis (inhibit the oxidation) of protein and lipids in dry-salted grass carp, illustrating that L-histidine and L-lysine will be a positive approach to develop healthier meat products.

The effect of a salt substitute (SS) containing L-lysine (Lys) and L-histidine (His) on secondary structure and gel properties of myosin from grass carp was examined. The results indicated that the α-helix content of myosin treated with SS was 29.00%, 29.03% and 35.93% more than that with NaCl at 0.4, 0.6 and 0.8 mol/L (P

For the development of low sodium gelled meat products, the influence of L-Lys, L-His and L-Lys + L-His on the gelation behaviour and gel properties of porcine myosin in low (1 mmol/L), physiological (0.15 mol/L) and high (0.6 mol/L) NaCl solutions were studied. The dynamic rheological results indicated that the introduction of L-Lys or/and L-His increased the storage moduli change rate (ΔG′) of myosin at 1 mmol/L, 0.15 mol/L and 0.6 mol/L NaCl concentrations. The ΔG’ of myosin in the presence of L-Lys was higher than that in the L-His at 1mmol/L- 0.6 mol/L NaCl. A significant increase in gel hardness was observed in the presence of L-Lys or/and L-His (P

To obtain healthier meat products with reduced Na content, the salt substitute containing l-histidine and l-lysine was compared with NaCl in the hydrolysis and oxidation of protein and lipids of dry-salted fish during processing. Compared with NaCl-treated fish (S-F), salt substitute treated fish (SS-F) had a lower Na content, higher moisture content and lower hardness. Sensory analysis showed that salt substitute didn't affect the acceptability of salted fish. The free fatty acids of SS-F treated fish had a slight tendency toward lipolysis at the end of processing. Additionally, the conjugated diene value, lipoxygenase activity and malondialdehyde value were lower in the ventral and dorsal muscles for the SS-F treatment. Meanwhile, the protein carbonyls and thiol groups were significantly decreased as cathepsin B and L activities and FAA content were increased in the ventral and dorsal muscles for the SS-F treatment. l-Histidine and l-lysine accelerated the hydrolysis (inhibit the oxidation) of protein and lipids in dry-salted grass carp, illustrating that l-histidine and l-lysine will be a positive approach to develop healthier meat products.

The effects of l -histidine (His) and l -lysine (Lys) on the emulsifying and interfacial properties of porcine myofibrillar proteins (MPs) at low/high ionic strength were investigated to improve physical stability of MPs emulsion at low ionic strength. Results showed that His and Lys increased emulsion stability index, and decreased creaming index at low ionic strength, but caused no significant changes in both indexes at high ionic strength. Additionaly, His and Lys increase d the emulsifying activity and apparent viscosity, but decreased the droplet size at both ionic strength. His and Lys also promoted the diffusion of MPs and increase d the interfacial pressure. Meanwhile, the interfacial loading of MPs was increased (p

The present study was designed to analyze the formation mechanics of heat-induced myofibrillar gels from rabbit psoas major at 0.6 mol/L KCl (pH 6.5) and 0.2 mol/L KCl (pH 6.0; n = 3). Morphological structure changes were observed using phase-contrast microscopy, transmission electron microscopy, scanning electron microscopy (SEM) and gel properties were determined through water-holding capacity (WHC), gel strength and dynamic rheological test. The results revealed that myofibrillar filaments aggregated and formed larger oligomers by side-by-side interactions when heated from 25 to 65°C. In higher ionic strength at higher pH, the filaments formed a more compact homogeneous network structure and the G′ value was much lower with higher WHC and gel strength, suggesting that the myofibril gel properties could be described by ∆G′. Based on the present study, it is suggested that the desired structural and textural attributes of myofibril gel can be manipulated by temperature, ionic strength and pH.

The objective of this study was to evaluate the effects of the suspended carcass deboning technique on the meat attributes of electrically stimulated cattle ( = 10). A carcass deboning technique that removes the main bones without breakdown of the entire carcass was applied to suspended sides soon after slaughter. After 3 d of aging at 4°C, the shear force of the rectus femoris, longissimus lumborum, and supraspinatus muscles of the suspended carcass deboning technique was reduced by 27%, 29%, and 23% ( 0.05). The carcass deboning technique could be a viable approach to improve beef tenderness with a relatively short aging duration.

Protein phosphorylation play an important role during the muscle conversing to meat. To obtain good meat quality with low NaCl content, the regulation effect of l -lysine and l -histidine on the myofibrillar and sarcoplasmic proteins phoshorylation at postmortem 90 min was investigated at 1% NaCl and 3% NaCl. Protein identification revealed that the phosphoproteins were mainly structural functions and energy metabolism proteins. At 1% NaCl level, neither l -histidine nor l -lysine caused remarkable change in myofibrillar proteins total phosphorylation level, while a significant decrease was obtained compared to 3% NaCl treatment when l -histidine and/or l -lysine were introduction (P l -histidine + L-lysine regardless of NaCl level. For individual protein, the influence of l -lysine and/or l -histidine on phosphorylation varied with NaCl level. It was demonstrated that l -lysine and l -histidine introduction might influence meat quality through protein phosphorylation at different NaCl level. This work provided an insight into the regulation of postmortem biological process to improve meat quality through incorporation of exogenous amino acids.

The present research investigated the antioxidant effect of rape (Brassica campestris L.) bee pollen (RBP) on salami during processing. Eight flavonoids in RBP ethanol extract were quantified by high-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis, and quercetin, rutin, and kaempferol were the major bioactive compounds. The RBP ethanol extract exhibited higher total antioxidant capacity than 6-hydroxy-2,5,7,8-tertramethylchromancarboxylic acid (trolox) at the same concentration. The salami with 0.05% RBP extract had higher catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities than that of the control throughout the processing time (p < 0.05). Significant decreases in peroxide value (POV) and thiobarbituric acid-reactive substances (TBARS) were obtained in the final salami product with 0.05% RBP ethanol extract or 1% RBP (p < 0.05). These results suggested that RBP could improve oxidative stability and had a good potential as a natural antioxidant for retarding lipid oxidation.

In previous studies, heterocyclic amines (HCAs) have been identified as carcinogenic and a risk factor for human cancer. Therefore, the present study was designed to identify bioactive natural products capable of controlling the formation of HCAs during cooking. For this purpose we have evaluated the effect of Rosa rugosa tea extract (RTE) on the formation of HCAs in ground beef patties fried at 160 °C or 220 °C. RTE is rich in phenolic compounds and capable of inhibiting the formation of free radicals. The pyrido[3,4-b]indole (norharman) and 1-methyl-9H-pyrido[3,4-b]indole (harman) contents were significantly (p < 0.05) decreased in RTE-treated patties at 220 °C. 9H-3-Amino-1-methyl-5H-pyrido[4,3-b]indole acetate (Trp-P-2) and 3-amino-1,4-dimethyl-5H-pyrido-[4,3-b]indole acetate (Trp-P-1) were not detected at 160 °C and were statistically (p < 0.01) reduced at 220 °C compared to the control. RTE remarkably inhibited the formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) at 220 °C (p < 0.001) and at 160 °C (p < 0.05). 2-Amino-9H-pyrido[2,3-b]indole (AαC) and 2-amino-3-methyl-9H-pyrido[2,3-b]-indole (MeAαC) were only detected in the control group at 160 °C but were comparatively (p > 0.05) similar in the control and treated groups at 220 °C. 2-Amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-3,4,8-trimethylimidazo[4,5-f]-quinoxaline (4,8-DiMeIQx) were not detected in any sample. Total HCAs were positively correlated with cooking loss. In the RTE-treated groups, 75% of the total HCAs were decreased at 160 °C and 46% at 220 °C, suggesting that RTE is effective at both temperatures and can be used during cooking at high temperatures to lessen the amount of HCAs formed.

The aim of the present study was to evaluate the effects of incorporating pig back fat in restructured dry cured ham (RDH) on its free fatty acid profile (FFA) and the volatile compounds released. Fresh raw hams were skinned, boned, and cut into meat cubes (4–6 × 4–6 × 4–6 cm). The meat cubes were restructured with 0, 2, and 4% pig back fat paste into raw restructured ham. After 30 days of ripening, the FFA and volatiles in the RDH were identified using gas chromatography and gas chromatography mass spectrometry, respectively. The results showed that exogenous pig back fat incorporation from 2 to 4% gave rise to increased neutral lipase activity (p

The aim of the present study was to evaluate the effect of incorporating pig back fat in restructured dry cured ham (RDH) on the lipase and lipoxygenase activities. Fresh raw hams were skinned, boned, cut into meat cubes (4–6 × 4–6 × 4–6 cm). The meat cubes were restructured respectively with 0, 2, and 4% pig back fat paste into raw restructured ham. After 30 days of ripening, lipase activity in RDH was determined using a fluorescence spectrometer (λex = 350 nm, λem = 445 nm), the result was expressed as µmol of released 4-methylumbelliferone per hour per gram protein. Lipoxygenase (LOX) activity in RDH was assayed in a 96-Well Plate Reader M200, one unit of LOX activity was defined as an absorbance increment per minute per milligram protein at 234 nm. Results showed that exogenous pig back fat incorporation from 2 to 4% gave rise to the increased neutral lipase and LOX activities (p