This work had an objective to evaluate the sensory quality of two categories of pork meat from a commercial pork meat and a selected meat from the Portuguese black pork (Preto Alentejano breed). Sixteen animals were u...This work had an objective to evaluate the sensory quality of two categories of pork meat from a commercial pork meat and a selected meat from the Portuguese black pork (Preto Alentejano breed). Sixteen animals were used, 8 females and 8 males from each breed. Animals had 80 - 100 kg of live weight. The longissimus muscle between the 5th thoracic vertebra and the 10th lumbar vertebra was used in the analysis. Sensory analysis was performed by a trained taste panel of 10 elements, in 5 sessions. All evaluation conditions were standardized, and the attributes studied were odor intensity, toughness, juiciness and flavor intensity. The taste panel found differences mainly between breeds. The panellists scored Preto Alentejano meat as being juicier, tenderer, and with richer taste than Commercial meat. The higher juiciness score of Preto Alentejano meat was probably attributable to the higher intramuscular fat content compared with Commercial meat. The Commercial pork was characterized mainly by high toughness.展开更多
The absence of efficient tools for preventing bacterial contamination in the meat processing industry as well as for detecting Salmonella positive samples in real time is a matter of concern. Impedance technology has ...The absence of efficient tools for preventing bacterial contamination in the meat processing industry as well as for detecting Salmonella positive samples in real time is a matter of concern. Impedance technology has proved its effectiveness as a bacterial quantification tool for research purposes instead of laborious standard plate count, and as a detection tool to substitute tedious current horizontal method ISO 6579：2002. Calibration curves were carded out for S. enteritidis and S. typhimurium in raw pork matrix （R2 〉 0.90）. Calibrations of mixtures of both strains at different ratio were prepared, showing a high efficiency to differentiate bacterial metabolism. Impediometry was also validated against standard plate count in raw pork samples treated by UV-C illumination to inactivate Salmonella. Even, damaged but still viable bacteria were recorded. Detection of Salmonella by impediometry led to a decrease in false positives, obtaining results within 30 h compared to 72 h in case of conventional method.展开更多
This work aimed to evaluate the physical-chemical characteristics of pork from a local breed （Portuguese black pork called Preto Alentejano） and a commercial breed. Sixteen animals were used, 4 females and 4 males f...This work aimed to evaluate the physical-chemical characteristics of pork from a local breed （Portuguese black pork called Preto Alentejano） and a commercial breed. Sixteen animals were used, 4 females and 4 males from each breed. Animals had 80-100 kg of live weight. The longissimus muscle between the 5th thoracic vertebra and the 10th lumbar vertebra was used in the analysis. Samples were analysed for protein, fat, pigments, ashes, dry mater, water-holding capacity, and texture. Results of fat and pigments contents indicate signiifcant （P〈0.05 and P〈0.01） differences for all treatments. For protein, ashes, dry mater, water-holding capacity and texture, no signiifcant differences were found for sex. In the analysis of fatty acids composition, ten were detected, being the main ones C16：0, C18：0, C16：1, C18：1, C18：2. There was a predominance of monounsaturated fatty acids （MUFA）, followed by saturated （SFA） and polyunsaturated （PUFA）. Differences were signiifcant for sex （P〈0.01） and breed （P〈0.01）. Preto Alentejano breed and females presented the higher percentages of SFA （P〈0.01） and MUFA （P〈0.001） fatty acids. Differences between breeds might be due to breed production system and feed differences.展开更多
This study investigated the relationship between the level of iron chemical forms and the initial raw meat pH values during cooking, including the effect of the sodium nitrite presence. The pH value, the heme iron （H...This study investigated the relationship between the level of iron chemical forms and the initial raw meat pH values during cooking, including the effect of the sodium nitrite presence. The pH value, the heme iron （HI） and non-heme iron （NHI） concentrations were measured on one ground portion of five loin, five masseter, five semimembranosus, five neck muscles and five shoulder muscles. Afterwards, all raw meats were halved and mixed with NaCl （2%）, ascorbic acid （0.05%） and 0 mg/kg of sodium nitrite （mix1） or 150 mg/kg of sodium nitrite （mix2）. Both mixes were divided into 50 g-portions, vacuum packed in cryovac bags and cooked in thermostatic bath up to F （10, 71 ℃） = 30 minutes at the core. The NHI and HI concentrations were determined both on the cooked meats and on the juice lost during cooking. The cooking process caused the release of NHl and H1 on all cooked sample juices. The HI overall percentage was significantly lower than raw meat one （P 〈 0.005） and the NHI significantly higher （P 〈 0.005） in all cooked mix 1. The raw and cooked HI percentage variances depended on the pork meat pH values （ra = 0.70）. The overall HI percentage was unchanged respect to raw meats on cooked mix 2, while the NHI amount was not quantitatively estimated. These results emphasized the role of sodium nitrite on tying up NHI in the cooked meats and safeguarding the oxidative stability of cooked meat products.展开更多
Pork hind legs have low fat and high protein contents,making cured pork prone to a dry and tough texture.To address this issue,0.8%(w/w)natural polysaccharide curdlan was added to cured pork.Physicochemical indicators...Pork hind legs have low fat and high protein contents,making cured pork prone to a dry and tough texture.To address this issue,0.8%(w/w)natural polysaccharide curdlan was added to cured pork.Physicochemical indicators,free amino acids,and flavor were tested on days 0,10,20,and 30 of curing.The results indicated that curdlan increased product yield by 4.08%,slowed moisture loss during processing,and reduced pH from 6.02 to 5.21.It also decreased the hardness,chewiness,and stickiness in cured pork hind legs,yielding a softer texture.In addition,it slowed the rate of color deterioration and inhibited fat oxidation.Analysis of volatile flavor compounds revealed that curdlan increased the variety of flavor compounds in cured pork hind legs by more than twenty types.The odor activity values of key aroma components(such as linalool and nonanal)also increased to varying degrees,enriching the flavor profile of the cured meat.Thus,curdlan effectively improves the texture,color,and flavor of cured pork hind legs,providing process parameters for industrial production of low-fat cured meat.展开更多
This study aimed to investigate the capabilities of hyperspectral scattering imaging in tandem with Gaussian function,Exponential function and Lorentzian function for rapid and nondestructive determination of total vi...This study aimed to investigate the capabilities of hyperspectral scattering imaging in tandem with Gaussian function,Exponential function and Lorentzian function for rapid and nondestructive determination of total viable count(TVC)in pork meat.Two batches of fresh pork meat was purchased from a local market and stored at 10°C for 1-9 d.Totally 60 samples were used,and several samples were taken out randomly for hyperspectral scattering imaging and conventional microbiological tests on each day of the experiments.The functions of Gaussian,Exponential and Lorentzian were employed to model the hyperspectral scattering profiles of pork meat,and good fitting results were obtained by all three functions between 455 nm and 1000 nm.The Lorentzian function performed best for fitting the hyperspectral scattering profiles of pork meat compared with other functions.Both principal component regression(PCR)and partial least squares regression(PLSR)methods were performed to establish the prediction models.Among all the developed models,the models developed using parameters CE(scattering width parameter of Exponential function)and CL(scattering width parameter of Lorentzian function)by PLSR method gave superior results for predicting pork meat TVC,with RV and RMSEV of 0.92,0.59 log CFU/g,and 0.91,0.61 log CFU/g,respectively.In addition,based on the improved hyperspectral scattering system,parameter c which represented the scattering widths in all three functions gave more accurate prediction results,regardless of the modeling methods(PCR or PLSR).The obtained results demonstrated that hyperspectral scattering imaging combined with the presented data analysis algorithm can be a powerful tool for evaluating the microbial safety of meat in the future.展开更多
In order to explore the resource utilization of the harmless treatment product(pork meat and bone meal,abbreviated PM)of pigs died of non-communicable diseases,the general nutritional components and amino acid composi...In order to explore the resource utilization of the harmless treatment product(pork meat and bone meal,abbreviated PM)of pigs died of non-communicable diseases,the general nutritional components and amino acid composition of PM and fish meal were determined and compared.The results showed that the contents of moisture,crude protein,crude fat and ash in PM and fish meal were 3.25%and 8.92%,66.65%and 66.67%,13.52%and 8.23%,18.25%and 21.50%,respectively.The contents of essential amino acids(EAA)in PM and fish meal were 19.94%and 22.35%,respectively.For PM and fish meal,the first limiting amino acid was Met(methionine)+Cys(cysteine),and the second limiting amino acid was Lys(lysine);their essential amino acid indexes(EAAI)were 66.60 and 77.04,respectively;and their delicious amino acid(DAA)contents were 26.89%and 23.15%,respectively.In summary,the meat and bone meal of pigs died of non-communicable diseases has the characteristics of high protein and low ash contents,and has certain development and utilization potential as a recycled waste resource,especially in aquatic feed to replace fish meal.展开更多
In this study, fresh pork tenderness, drip-loss, pH value and color parameters （ CIE, a ＊ , b ＊ and L ＊ values） were simultaneously predicted using hyperspectral scattering imaging （HSI） technique. The hyperspe...In this study, fresh pork tenderness, drip-loss, pH value and color parameters （ CIE, a ＊ , b ＊ and L ＊ values） were simultaneously predicted using hyperspectral scattering imaging （HSI） technique. The hyperspectral scattering images of dO fresh pork samples were collected at the wavelength of 400 -I 100 nm, and the scattering profiles were fitted via Lorontzian distribution （ LD ） function to give three parameters a （ asymptotic value ）, b （peak value ） and c （ full width at b/2）. Stepwise discrimination was performed to determine the optimal wavelengths combinations. The LD parameters combinations （a, b and c） of optimal wavelengths were used to establish multi-linear regression （MLR） models to predict the pork attributes. The models were able to predict pork with high correlation coefficients of 0.92 for drip-loss, 0.94, 0.92 and 0.98 respectively for color parameters （ a ＊ , b＊ and L ＊ ）, and for tenderness and pH value the models gave the correlation coefficients of 0.69 and 0.76, respectively. These results showed that the hyperspectral scattering technique was capable of predicting quality parameters of perk. The study provides an efficient means for rapid and nondestructive determination of pork quality simultaneously.展开更多
文摘This work had an objective to evaluate the sensory quality of two categories of pork meat from a commercial pork meat and a selected meat from the Portuguese black pork (Preto Alentejano breed). Sixteen animals were used, 8 females and 8 males from each breed. Animals had 80 - 100 kg of live weight. The longissimus muscle between the 5th thoracic vertebra and the 10th lumbar vertebra was used in the analysis. Sensory analysis was performed by a trained taste panel of 10 elements, in 5 sessions. All evaluation conditions were standardized, and the attributes studied were odor intensity, toughness, juiciness and flavor intensity. The taste panel found differences mainly between breeds. The panellists scored Preto Alentejano meat as being juicier, tenderer, and with richer taste than Commercial meat. The higher juiciness score of Preto Alentejano meat was probably attributable to the higher intramuscular fat content compared with Commercial meat. The Commercial pork was characterized mainly by high toughness.
文摘The absence of efficient tools for preventing bacterial contamination in the meat processing industry as well as for detecting Salmonella positive samples in real time is a matter of concern. Impedance technology has proved its effectiveness as a bacterial quantification tool for research purposes instead of laborious standard plate count, and as a detection tool to substitute tedious current horizontal method ISO 6579：2002. Calibration curves were carded out for S. enteritidis and S. typhimurium in raw pork matrix （R2 〉 0.90）. Calibrations of mixtures of both strains at different ratio were prepared, showing a high efficiency to differentiate bacterial metabolism. Impediometry was also validated against standard plate count in raw pork samples treated by UV-C illumination to inactivate Salmonella. Even, damaged but still viable bacteria were recorded. Detection of Salmonella by impediometry led to a decrease in false positives, obtaining results within 30 h compared to 72 h in case of conventional method.
文摘This work aimed to evaluate the physical-chemical characteristics of pork from a local breed （Portuguese black pork called Preto Alentejano） and a commercial breed. Sixteen animals were used, 4 females and 4 males from each breed. Animals had 80-100 kg of live weight. The longissimus muscle between the 5th thoracic vertebra and the 10th lumbar vertebra was used in the analysis. Samples were analysed for protein, fat, pigments, ashes, dry mater, water-holding capacity, and texture. Results of fat and pigments contents indicate signiifcant （P〈0.05 and P〈0.01） differences for all treatments. For protein, ashes, dry mater, water-holding capacity and texture, no signiifcant differences were found for sex. In the analysis of fatty acids composition, ten were detected, being the main ones C16：0, C18：0, C16：1, C18：1, C18：2. There was a predominance of monounsaturated fatty acids （MUFA）, followed by saturated （SFA） and polyunsaturated （PUFA）. Differences were signiifcant for sex （P〈0.01） and breed （P〈0.01）. Preto Alentejano breed and females presented the higher percentages of SFA （P〈0.01） and MUFA （P〈0.001） fatty acids. Differences between breeds might be due to breed production system and feed differences.
文摘This study investigated the relationship between the level of iron chemical forms and the initial raw meat pH values during cooking, including the effect of the sodium nitrite presence. The pH value, the heme iron （HI） and non-heme iron （NHI） concentrations were measured on one ground portion of five loin, five masseter, five semimembranosus, five neck muscles and five shoulder muscles. Afterwards, all raw meats were halved and mixed with NaCl （2%）, ascorbic acid （0.05%） and 0 mg/kg of sodium nitrite （mix1） or 150 mg/kg of sodium nitrite （mix2）. Both mixes were divided into 50 g-portions, vacuum packed in cryovac bags and cooked in thermostatic bath up to F （10, 71 ℃） = 30 minutes at the core. The NHI and HI concentrations were determined both on the cooked meats and on the juice lost during cooking. The cooking process caused the release of NHl and H1 on all cooked sample juices. The HI overall percentage was significantly lower than raw meat one （P 〈 0.005） and the NHI significantly higher （P 〈 0.005） in all cooked mix 1. The raw and cooked HI percentage variances depended on the pork meat pH values （ra = 0.70）. The overall HI percentage was unchanged respect to raw meats on cooked mix 2, while the NHI amount was not quantitatively estimated. These results emphasized the role of sodium nitrite on tying up NHI in the cooked meats and safeguarding the oxidative stability of cooked meat products.
基金Supported by Sichuan Science and Technology Program(2024ZHCG0091)National Modern Agricultural Industry Technology System Sichuan Swine Innovation Team(SCCXTD-2025-8)+1 种基金Open Fund of Sichuan Provincial Key Laboratory of Meat Processing(24-R-20)China Agricultural Industry Research System(CARS-43).
文摘Pork hind legs have low fat and high protein contents,making cured pork prone to a dry and tough texture.To address this issue,0.8%(w/w)natural polysaccharide curdlan was added to cured pork.Physicochemical indicators,free amino acids,and flavor were tested on days 0,10,20,and 30 of curing.The results indicated that curdlan increased product yield by 4.08%,slowed moisture loss during processing,and reduced pH from 6.02 to 5.21.It also decreased the hardness,chewiness,and stickiness in cured pork hind legs,yielding a softer texture.In addition,it slowed the rate of color deterioration and inhibited fat oxidation.Analysis of volatile flavor compounds revealed that curdlan increased the variety of flavor compounds in cured pork hind legs by more than twenty types.The odor activity values of key aroma components(such as linalool and nonanal)also increased to varying degrees,enriching the flavor profile of the cured meat.Thus,curdlan effectively improves the texture,color,and flavor of cured pork hind legs,providing process parameters for industrial production of low-fat cured meat.
基金The authors gratefully acknowledge the China Postdoctoral Science Foundation(Project No.2014M561096)the Special Fund for Agro-scientific Research in the Public Interest Program(Project No.201003008)the National Science and Technology Support Program(Project No.2012BAH04B00)for supporting this research.
文摘This study aimed to investigate the capabilities of hyperspectral scattering imaging in tandem with Gaussian function,Exponential function and Lorentzian function for rapid and nondestructive determination of total viable count(TVC)in pork meat.Two batches of fresh pork meat was purchased from a local market and stored at 10°C for 1-9 d.Totally 60 samples were used,and several samples were taken out randomly for hyperspectral scattering imaging and conventional microbiological tests on each day of the experiments.The functions of Gaussian,Exponential and Lorentzian were employed to model the hyperspectral scattering profiles of pork meat,and good fitting results were obtained by all three functions between 455 nm and 1000 nm.The Lorentzian function performed best for fitting the hyperspectral scattering profiles of pork meat compared with other functions.Both principal component regression(PCR)and partial least squares regression(PLSR)methods were performed to establish the prediction models.Among all the developed models,the models developed using parameters CE(scattering width parameter of Exponential function)and CL(scattering width parameter of Lorentzian function)by PLSR method gave superior results for predicting pork meat TVC,with RV and RMSEV of 0.92,0.59 log CFU/g,and 0.91,0.61 log CFU/g,respectively.In addition,based on the improved hyperspectral scattering system,parameter c which represented the scattering widths in all three functions gave more accurate prediction results,regardless of the modeling methods(PCR or PLSR).The obtained results demonstrated that hyperspectral scattering imaging combined with the presented data analysis algorithm can be a powerful tool for evaluating the microbial safety of meat in the future.
基金Major Science and Technology Special Project in Hunan(2017NK1030)Earmarked Fund for China Agriculture Research System(CARS-45-48)。
文摘In order to explore the resource utilization of the harmless treatment product(pork meat and bone meal,abbreviated PM)of pigs died of non-communicable diseases,the general nutritional components and amino acid composition of PM and fish meal were determined and compared.The results showed that the contents of moisture,crude protein,crude fat and ash in PM and fish meal were 3.25%and 8.92%,66.65%and 66.67%,13.52%and 8.23%,18.25%and 21.50%,respectively.The contents of essential amino acids(EAA)in PM and fish meal were 19.94%and 22.35%,respectively.For PM and fish meal,the first limiting amino acid was Met(methionine)+Cys(cysteine),and the second limiting amino acid was Lys(lysine);their essential amino acid indexes(EAAI)were 66.60 and 77.04,respectively;and their delicious amino acid(DAA)contents were 26.89%and 23.15%,respectively.In summary,the meat and bone meal of pigs died of non-communicable diseases has the characteristics of high protein and low ash contents,and has certain development and utilization potential as a recycled waste resource,especially in aquatic feed to replace fish meal.
基金Supported by Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi Province(2013123)
文摘In this study, fresh pork tenderness, drip-loss, pH value and color parameters （ CIE, a ＊ , b ＊ and L ＊ values） were simultaneously predicted using hyperspectral scattering imaging （HSI） technique. The hyperspectral scattering images of dO fresh pork samples were collected at the wavelength of 400 -I 100 nm, and the scattering profiles were fitted via Lorontzian distribution （ LD ） function to give three parameters a （ asymptotic value ）, b （peak value ） and c （ full width at b/2）. Stepwise discrimination was performed to determine the optimal wavelengths combinations. The LD parameters combinations （a, b and c） of optimal wavelengths were used to establish multi-linear regression （MLR） models to predict the pork attributes. The models were able to predict pork with high correlation coefficients of 0.92 for drip-loss, 0.94, 0.92 and 0.98 respectively for color parameters （ a ＊ , b＊ and L ＊ ）, and for tenderness and pH value the models gave the correlation coefficients of 0.69 and 0.76, respectively. These results showed that the hyperspectral scattering technique was capable of predicting quality parameters of perk. The study provides an efficient means for rapid and nondestructive determination of pork quality simultaneously.
