Mari Tørngren - Academia.edu (original) (raw)

Papers by Mari Tørngren

Food Packaging and Shelf Life, Mar 1, 2014

Abstract The oxidative stability and sensory quality of chicken breast ( m. pectoralis ) and thig... more Abstract The oxidative stability and sensory quality of chicken breast ( m. pectoralis ) and thigh ( m. peroneus longus ) stored in high-oxygen modified atmosphere (MAP-O 2 ), non-oxygen modified atmosphere (MAP-N 2 ), or vacuum for up to 9 days at 5 °C were investigated. Protein thiol concentration in breasts and thighs decreased significantly between 5 and 9 days storage in MAP-O 2 compared to non-oxygen storage, and resulted in myosin heavy chain disulfide cross-links. Thiol loss and protein cross-link formation were more pronounced in thighs compared to breasts, and a similar tendency was seen for the formation of secondary lipid oxidation products. However, while breast stored in MAP-O 2 clearly scored lower in tenderness and higher in rancidity compared to breast in non-oxygen storage, the effect of MAP-O 2 for the sensory quality of thigh was negligible. These results show that thigh is more suitable for storage in MAP-O 2 than breast, indicating that the negative effect MAP-O 2 may have on the oxidative stability and sensory quality of meat varies between different muscles.

Archivos Latinoamericanos de Producción Animal, 2014

Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive... more Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive bloom colour on the surface of the meat and to extend the microbial shelf life. Unfortunately, the gas composition consisting of 70-80% oxygen (O2) and 20-30% carbon dioxide (CO2) results in less tender and less juicy meat with a more rancid flavour compared with wrapped or vacuum-packed pork. To establish whether three-gas MAP (O2, CO2 and N2) with less oxygen, instead of two-gas MAP, would affect sensory attributes, shelf life and colour stability, enhanced and enhanced + marinated pork chops were packed in MAP with 0%, 40% or 80% O2 and 20% or 40% CO2 an N2 as filler gas. However, it was not possible to optimise the eating quality and shelf life of enhanced pork chops without compromising the acceptance of the raw meat, as seen for fresh pork. By marinating enhanced pork chops, the acceptance limit was extended by two to seven days depending on the gas mixture, and differences in eating quality were equalised. It is recommended to pack enhanced pork chops and enhanced + marinated pork in an anoxic atmosphere (20% CO2 + 80% N2) to preserve the appearance, flavour and texture of the meat.

Medicines, Jan 22, 2018

Background: Phenolic plant extracts are added as antioxidants in meat to prevent lipid oxidation,... more Background: Phenolic plant extracts are added as antioxidants in meat to prevent lipid oxidation, but depending on the concentration applied, may affect proteins either through covalent interactions or by serving as a prooxidant. Methods: Brine-injected pork chops prepared with green tea extract (25-160 ppm gallic acid equivalents (GAE)), or maté extract (25-160 ppm GAE) and stored (5 • C, 7 days) in high-oxygen atmosphere packaging (MAP: 80% O2 and 20% CO2) were analyzed for color changes, lipid oxidation by thiobarbituric acid reactive substances (TBARS), and protein oxidation evaluated by thiol loss and protein radical formation by electron spin resonance (ESR) spectroscopy, and compared to a control without antioxidant. Results: Extract of maté and green tea showed significant and comparable antioxidative effects against formation of TBARS in brine-injected pork chops for all concentrations applied compared to the control. Protein radical formation decreased significantly by addition of 25 ppm maté extract, but increased significantly by addition of 80-160 ppm green tea extract, when monitored as formation of protein radicals. Meanwhile, protein thiol groups disappeared when applying the extracts by reactions assigned to addition reactions of oxidized phenols from the extracts to protein thiols. Conclusion: Maté is accordingly a good source of antioxidants for protection of both lipids and proteins in brine-injected pork chops chill-stored in high-oxygen atmosphere, though the dose must be carefully selected.

Medicines, Jan 15, 2018

Background: Ascorbate is often applied to enhance stability and robustness of brine-injected pork... more Background: Ascorbate is often applied to enhance stability and robustness of brine-injected pork chops sold for retail, but may affect protein oxidation, while plant extracts are potential substitutes. Methods: Brine-injected pork chops (weight-gain~12%, NaCl~0.9%) prepared with ascorbate (225 ppm), green tea extract (25 ppm gallic acid equivalents (GAE)), or maté extract (25 ppm GAE) stored (5 • C, seven days) in high-oxygen atmosphere packaging (MAP: 80% O 2 and 20% CO 2) were analyzed for color changes, sensory quality, and protein oxidation compared to a control without antioxidant. Results: No significant differences were observed for green tea and maté extracts as compared to ascorbate when evaluated based on lipid oxidation derived off-flavors, except for stale flavor, which maté significantly reduced. All treatments increased the level of the protein oxidation product, α-aminoadipic semialdehyde as compared to the control, and ascorbate was further found to increase thiol loss and protein cross-linking, with a concomitant decrease in the sensory perceived tenderness. Conclusions: Green tea and maté were found to equally protect against lipid oxidation derived off-flavors, and maté showed less prooxidative activity towards proteins as compared to ascorbate, resulting in more tender meat. Maté is a valuable substitute for ascorbate in brine-injected pork chops.

Meat Science, Feb 1, 2012

The present study evaluated the sensory characteristics of low temperature long time (LTLT) treat... more The present study evaluated the sensory characteristics of low temperature long time (LTLT) treated Semitendinosus from pork and beef and Pectoralis profundus from chicken. Semitendinosus and Pectoralis profundus muscles were heat treated at 53 °C and 58 °C for T(c) + 6 h, T(c) + 17 h, and T(c) + 30 h (only Semitendinosus from pork and beef). T(c) was the time for the samples to equalize with the temperature in the water bath. Tenderness increased with increasing heating temperature and time in pork and beef, but not in chicken. Juiciness decreased with increasing heating temperature and time in all species, and cooking loss increased with increasing temperature. A done appearance was developed with increasing heating time at 58 °C in pork and beef, while in chicken the done appearance was only affected by temperature. Flavor attributes were less affected by the LTLT treatment for all species.

 Users may download and print one copy of any publication from the public portal for the purpose... more  Users may download and print one copy of any publication from the public portal for the purpose of private study or research.  You may not further distribute the material or use it for any profit-making activity or commercial gain  You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.

Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive... more Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive bloom colour on the surface of the meat and to extend the microbial shelf-life. Unfortunately, the gas composition consisting of 70-80% oxygen (O 2) and 20-30% carbon dioxide (CO 2) results in less tender and less juicy meat with a more rancid flavour compared with wrapped or vacuumpacked pork. To establish whether three-gas MAP (O 2 , CO 2 and N 2), instead of two-gas MAP, would affect sensory attributes, shelf-life and colour stability, three different retail cuts were packed in MAP with 0%, 40%, 50% or 80% O 2 and 20% or 40% CO 2. Packing pork chops and schnitzels in 40% O 2 + 20% CO 2 + 40% N 2 maintained the shelf-life and resulted in more tender, more juicy and less rancid pork compared with traditional MAP, and packing sliced pork belly in 50% O 2 , 40% CO 2 and 10% N 2 resulted in a more crispy texture and a less stale and bitter taste. Three-gas MAP could therefore be a suitable alternative to traditional MAP, maintaining shelf-life and enhancing eating quality.

Meat Science, Mar 1, 2016

Visible spectroscopy as a tool for the assessment of storage conditions of fresh pork packaged in... more Visible spectroscopy as a tool for the assessment of storage conditions of fresh pork packaged in modified atmosphere The storage conditions of fresh meat are known to impact its colour and microbial shelf life. In the present study, visible spectroscopy was evaluated as a method to assess meat storage conditions and its optimisation. Fresh pork steaks (longissimus thoracis et lumborum and semimembranosus) were placed in modified atmosphere packaging using gas mixtures containing 0, 40, 50, and 80% oxygen, and stored with or without light for up to 9days. Principal component analysis of visible reflectance spectra (400-700nm) showed that the colour of the different meat cuts was affected by presence of oxygen, illumination, and storage time. Differences in the oxygen levels did not contribute to the observed variance. Predictive models based on partial least squares regression-discriminant analysis exhibited high potency in the classification of the storage parameters of meat cuts packaged in modified atmosphere. The study demonstrates the applicability of visible spectroscopy as a tool to assess the storage conditions of meat cuts packaged in modified atmosphere.

Elsevier eBooks, 2014

With the exception of specially dried and fermented products, meat is generally cooked before con... more With the exception of specially dried and fermented products, meat is generally cooked before consumption. Biochemical and physical changes occur during the heating process and these changes affect microbiological quality and sensory characteristics. As the temperature increases during cooking, the meat protein starts to denature. From approximately 60 °C, denaturation of myoglobin takes place and the meat starts to look well-done. The eating quality depends on the cooking methods and other cooking methods that are discussed in this article. For all methods, the temperature control during cooking is furthermore crucial for the resulting eating quality.

Meat Science, Jul 1, 2010

Beef steaks retail-packed with (80% O(2), 20% CO(2)) or without oxygen (either skin-packed or gas... more Beef steaks retail-packed with (80% O(2), 20% CO(2)) or without oxygen (either skin-packed or gas-packed (69.6% N(2), 30% CO(2), 0.04% CO or 70% N(2), 30% CO(2))) were compared by consumers in Denmark (n=382), Norway (n=316) and Sweden (n=374). Two pairs of two steaks - one steak packed in a high oxygen atmosphere and one packed without oxygen - were given to the consumers. They were instructed to prepare the steaks at home on two consecutive days, and two persons had to taste each steak. In Denmark, the oxygen-free packing was either gas packing with CO (69.6% N(2), 30% CO(2), 0.04% CO) or without CO (70% N(2), 30% CO(2)), in Norway it was either gas packing with CO (69.6% N(2), 30% CO(2), 0.04% CO) or skin packing, and in Sweden it was either skin packing or gas packing without CO (70% N(2), 30% CO(2)). The meat represented animals that were between 17 and 80 months old (Denmark) and young bulls (Norway and Sweden). Consumers in all three countries clearly preferred steaks packed without oxygen, in terms of overall liking, willingness to pay and their preferred choice of one steak. Furthermore, they preferred the oxygen-free steaks in terms of both overall liking and liking of tenderness, juiciness and flavour. In Sweden, many consumers would pay more than usual for the skin-packed steak, and it was more often chosen as the preferred steak out of the four compared with gas-packed without oxygen. No difference was seen between the two oxygen-free packing methods in Denmark and Norway.

Journal of Agricultural and Food Chemistry, Sep 2, 2006

Inosine monophosphate (IMP) and its degradation products, ribose and hypoxanthine, are all consid... more Inosine monophosphate (IMP) and its degradation products, ribose and hypoxanthine, are all considered to be important constituents in meat flavor formation and development. The present study explored the fate of IMP during the aging of two qualities of pork (pH >5.7 and 5.5 < pH < 5.6) and the potential relationship between IMP, hypoxanthine, and sensory attributes of pork registered both as retronasal and basic taste responses in whole meat, meat juice, and the remaining meat residue. During aging the concentration of IMP decreased with a simultaneous increase in the concentrations of inosine, hypoxanthine, and ribose. The rates at which IMP was degraded to inosine and inosine to hypoxanthine during aging were found to be in agreement with the known rate constants of the dephosphorylation of IMP and the hydrolysis of inosine, respectively. Moreover, high-pH pork resulted in a significantly higher concentration of hypoxanthine throughout storage compared with low-pH pork due to an initially higher concentration of IMP in high-pH meat. The sensory analysis showed increasing intensity in bitterness and saltiness of pork as a function of aging, with the intensity being most pronounced in the meat juice. The increasing bitterness of the pork as a function of aging coincided with the higher content of hypoxanthine in these samples, thereby suggesting that degradation of IMP to hypoxanthine might influence pork flavor. In contrast, IMP was associated with nonaged meat and the sensory attributes meaty and brothy.

Journal of the Science of Food and Agriculture, May 22, 2009

BACKGROUND: Marination of beef muscles with brine solutions containing proteolytic enzymes from f... more BACKGROUND: Marination of beef muscles with brine solutions containing proteolytic enzymes from fruit extracts has been shown to tenderize meat. However, the effect of marination with actinidin on tenderness of pork muscles has not been investigated. Tenderness and eating quality of porcine M. biceps femoris was investigated by Warner-Bratzler (WB) shear test and sensory evaluation after injection of brine containing up to 11 g L −1 actinidin-containing kiwi fruit powder and 2, 5 or 9 days of storage. RESULTS: Actinidin decreased WB shear force, increased tenderness and did not affect flavour and juiciness. Injection of 2.8 g L −1 actinidin powder and storage for 2 days resulted in WB shear force values similar to control samples stored for 5 or 9 days. In samples injected with 10 g L −1 actinidin powder, degradation of desmin and percentage of heat-soluble collagen (P < 0.05) increased compared to control samples. Myofibrillar particle size tended to decrease (P < 0.1) with increasing actinidin concentration. No major changes were observed by proteome analysis. Atomic force microscopy showed actinidin-induced damage of endomysium surrounding isolated single muscle fibres. CONCLUSION: Our results indicate that actinidin tenderizes pork M. biceps femoris by affecting both the myofibrils and connective tissue.

Meat Science, Mar 1, 2016

Effect of oxygen level on the oxidative stability of two different retail pork products stored us... more Effect of oxygen level on the oxidative stability of two different retail pork products stored using modified atmosphere packaging (MAP) The characteristics and the oxidative stability of pork steaks and of pork mince were investigated during 2, 5 and 7 days of refrigerated storage using oxygen (O2) levels of 0%, 20%, 50% and 80% in modified atmosphere packaging (MAP). Steaks stored during 7 days were not affected by an increase in O2 concentration, as revealed by lipid and protein oxidation markers. In contrast, the mince was characterised by an altered protein profile, loss of free thiol groups and increased protein oxidation, early during storage. The oxidative stability of pork mince was improved by using intermediate (50%) O2 MAP. The results show that fresh pork products are affected differently by the MAP O2 concentration and strongly indicate that optimisation of MAP based on the retail product type would be of considerable benefit to their oxidative stability.

To optimize eating quality of fresh meat in modified atmosphere packaging (MAP), oxygen exposure ... more To optimize eating quality of fresh meat in modified atmosphere packaging (MAP), oxygen exposure has to be minimized. Oxygen pressure in the headspace is highly responsible for the chemical state of the myoglobin, and through that the colour of the raw meat. Oxygen consumption is muscle specific and has to be balanced with the oxygen content in the gas mixture to achieve an attractive red surface throughout shelf life and to minimize oxidation of proteins and lipids. To establish whether low O2 three-gas MAP (O2, CO2 and N2) could increase sensory quality without compromising shelf life and colour stability, aged strip loin steaks were retail packed in MAP with 30%, 40%, 50% or 70% O2 and 30% CO2. Packing of beef steaks in 30% O2 + 30% CO2 + 40% N2 resulted in more tender, more juicy and less rancid steaks compared with beef steaks packed in traditional MAP (70% O2 + 30% CO2). Three-gas MAP could therefore be a suitable alternative to traditional MAP, maintaining shelf life and colour stability and increasing eating quality.

Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive... more Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive bloom colour on the surface of the meat and to extend the microbial shelf life. Unfortunately, the gas composition consisting of 70-80% oxygen (O2) and 20-30% carbon dioxide (CO2) results in less tender and less juicy meat with a more rancid flavour compared with wrapped or vacuum-packed pork. To establish whether three-gas MAP (O2, CO2 and N2) with less oxygen, instead of two-gas MAP, would affect sensory attributes, shelf life and colour stability, enhanced and enhanced + marinated pork chops were packed in MAP with 0%, 40% or 80% O2 and 20% or 40% CO2 an N2 as filler gas. However, it was not possible to optimise the eating quality and shelf life of enhanced pork chops without compromising the acceptance of the raw meat, as seen for fresh pork. By marinating enhanced pork chops, the acceptance limit was extended by two to seven days depending on the gas mixture, and differences in eat...

Food Packaging and Shelf Life, Mar 1, 2014

Abstract The oxidative stability and sensory quality of chicken breast ( m. pectoralis ) and thig... more Abstract The oxidative stability and sensory quality of chicken breast ( m. pectoralis ) and thigh ( m. peroneus longus ) stored in high-oxygen modified atmosphere (MAP-O 2 ), non-oxygen modified atmosphere (MAP-N 2 ), or vacuum for up to 9 days at 5 °C were investigated. Protein thiol concentration in breasts and thighs decreased significantly between 5 and 9 days storage in MAP-O 2 compared to non-oxygen storage, and resulted in myosin heavy chain disulfide cross-links. Thiol loss and protein cross-link formation were more pronounced in thighs compared to breasts, and a similar tendency was seen for the formation of secondary lipid oxidation products. However, while breast stored in MAP-O 2 clearly scored lower in tenderness and higher in rancidity compared to breast in non-oxygen storage, the effect of MAP-O 2 for the sensory quality of thigh was negligible. These results show that thigh is more suitable for storage in MAP-O 2 than breast, indicating that the negative effect MAP-O 2 may have on the oxidative stability and sensory quality of meat varies between different muscles.

Archivos Latinoamericanos de Producción Animal, 2014

Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive... more Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive bloom colour on the surface of the meat and to extend the microbial shelf life. Unfortunately, the gas composition consisting of 70-80% oxygen (O2) and 20-30% carbon dioxide (CO2) results in less tender and less juicy meat with a more rancid flavour compared with wrapped or vacuum-packed pork. To establish whether three-gas MAP (O2, CO2 and N2) with less oxygen, instead of two-gas MAP, would affect sensory attributes, shelf life and colour stability, enhanced and enhanced + marinated pork chops were packed in MAP with 0%, 40% or 80% O2 and 20% or 40% CO2 an N2 as filler gas. However, it was not possible to optimise the eating quality and shelf life of enhanced pork chops without compromising the acceptance of the raw meat, as seen for fresh pork. By marinating enhanced pork chops, the acceptance limit was extended by two to seven days depending on the gas mixture, and differences in eating quality were equalised. It is recommended to pack enhanced pork chops and enhanced + marinated pork in an anoxic atmosphere (20% CO2 + 80% N2) to preserve the appearance, flavour and texture of the meat.

Medicines, Jan 22, 2018

Background: Phenolic plant extracts are added as antioxidants in meat to prevent lipid oxidation,... more Background: Phenolic plant extracts are added as antioxidants in meat to prevent lipid oxidation, but depending on the concentration applied, may affect proteins either through covalent interactions or by serving as a prooxidant. Methods: Brine-injected pork chops prepared with green tea extract (25-160 ppm gallic acid equivalents (GAE)), or maté extract (25-160 ppm GAE) and stored (5 • C, 7 days) in high-oxygen atmosphere packaging (MAP: 80% O2 and 20% CO2) were analyzed for color changes, lipid oxidation by thiobarbituric acid reactive substances (TBARS), and protein oxidation evaluated by thiol loss and protein radical formation by electron spin resonance (ESR) spectroscopy, and compared to a control without antioxidant. Results: Extract of maté and green tea showed significant and comparable antioxidative effects against formation of TBARS in brine-injected pork chops for all concentrations applied compared to the control. Protein radical formation decreased significantly by addition of 25 ppm maté extract, but increased significantly by addition of 80-160 ppm green tea extract, when monitored as formation of protein radicals. Meanwhile, protein thiol groups disappeared when applying the extracts by reactions assigned to addition reactions of oxidized phenols from the extracts to protein thiols. Conclusion: Maté is accordingly a good source of antioxidants for protection of both lipids and proteins in brine-injected pork chops chill-stored in high-oxygen atmosphere, though the dose must be carefully selected.

Medicines, Jan 15, 2018

Background: Ascorbate is often applied to enhance stability and robustness of brine-injected pork... more Background: Ascorbate is often applied to enhance stability and robustness of brine-injected pork chops sold for retail, but may affect protein oxidation, while plant extracts are potential substitutes. Methods: Brine-injected pork chops (weight-gain~12%, NaCl~0.9%) prepared with ascorbate (225 ppm), green tea extract (25 ppm gallic acid equivalents (GAE)), or maté extract (25 ppm GAE) stored (5 • C, seven days) in high-oxygen atmosphere packaging (MAP: 80% O 2 and 20% CO 2) were analyzed for color changes, sensory quality, and protein oxidation compared to a control without antioxidant. Results: No significant differences were observed for green tea and maté extracts as compared to ascorbate when evaluated based on lipid oxidation derived off-flavors, except for stale flavor, which maté significantly reduced. All treatments increased the level of the protein oxidation product, α-aminoadipic semialdehyde as compared to the control, and ascorbate was further found to increase thiol loss and protein cross-linking, with a concomitant decrease in the sensory perceived tenderness. Conclusions: Green tea and maté were found to equally protect against lipid oxidation derived off-flavors, and maté showed less prooxidative activity towards proteins as compared to ascorbate, resulting in more tender meat. Maté is a valuable substitute for ascorbate in brine-injected pork chops.

Meat Science, Feb 1, 2012

The present study evaluated the sensory characteristics of low temperature long time (LTLT) treat... more The present study evaluated the sensory characteristics of low temperature long time (LTLT) treated Semitendinosus from pork and beef and Pectoralis profundus from chicken. Semitendinosus and Pectoralis profundus muscles were heat treated at 53 °C and 58 °C for T(c) + 6 h, T(c) + 17 h, and T(c) + 30 h (only Semitendinosus from pork and beef). T(c) was the time for the samples to equalize with the temperature in the water bath. Tenderness increased with increasing heating temperature and time in pork and beef, but not in chicken. Juiciness decreased with increasing heating temperature and time in all species, and cooking loss increased with increasing temperature. A done appearance was developed with increasing heating time at 58 °C in pork and beef, while in chicken the done appearance was only affected by temperature. Flavor attributes were less affected by the LTLT treatment for all species.

 Users may download and print one copy of any publication from the public portal for the purpose... more  Users may download and print one copy of any publication from the public portal for the purpose of private study or research.  You may not further distribute the material or use it for any profit-making activity or commercial gain  You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.

Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive... more Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive bloom colour on the surface of the meat and to extend the microbial shelf-life. Unfortunately, the gas composition consisting of 70-80% oxygen (O 2) and 20-30% carbon dioxide (CO 2) results in less tender and less juicy meat with a more rancid flavour compared with wrapped or vacuumpacked pork. To establish whether three-gas MAP (O 2 , CO 2 and N 2), instead of two-gas MAP, would affect sensory attributes, shelf-life and colour stability, three different retail cuts were packed in MAP with 0%, 40%, 50% or 80% O 2 and 20% or 40% CO 2. Packing pork chops and schnitzels in 40% O 2 + 20% CO 2 + 40% N 2 maintained the shelf-life and resulted in more tender, more juicy and less rancid pork compared with traditional MAP, and packing sliced pork belly in 50% O 2 , 40% CO 2 and 10% N 2 resulted in a more crispy texture and a less stale and bitter taste. Three-gas MAP could therefore be a suitable alternative to traditional MAP, maintaining shelf-life and enhancing eating quality.

Meat Science, Mar 1, 2016

Visible spectroscopy as a tool for the assessment of storage conditions of fresh pork packaged in... more Visible spectroscopy as a tool for the assessment of storage conditions of fresh pork packaged in modified atmosphere The storage conditions of fresh meat are known to impact its colour and microbial shelf life. In the present study, visible spectroscopy was evaluated as a method to assess meat storage conditions and its optimisation. Fresh pork steaks (longissimus thoracis et lumborum and semimembranosus) were placed in modified atmosphere packaging using gas mixtures containing 0, 40, 50, and 80% oxygen, and stored with or without light for up to 9days. Principal component analysis of visible reflectance spectra (400-700nm) showed that the colour of the different meat cuts was affected by presence of oxygen, illumination, and storage time. Differences in the oxygen levels did not contribute to the observed variance. Predictive models based on partial least squares regression-discriminant analysis exhibited high potency in the classification of the storage parameters of meat cuts packaged in modified atmosphere. The study demonstrates the applicability of visible spectroscopy as a tool to assess the storage conditions of meat cuts packaged in modified atmosphere.

Elsevier eBooks, 2014

With the exception of specially dried and fermented products, meat is generally cooked before con... more With the exception of specially dried and fermented products, meat is generally cooked before consumption. Biochemical and physical changes occur during the heating process and these changes affect microbiological quality and sensory characteristics. As the temperature increases during cooking, the meat protein starts to denature. From approximately 60 °C, denaturation of myoglobin takes place and the meat starts to look well-done. The eating quality depends on the cooking methods and other cooking methods that are discussed in this article. For all methods, the temperature control during cooking is furthermore crucial for the resulting eating quality.

Meat Science, Jul 1, 2010

Beef steaks retail-packed with (80% O(2), 20% CO(2)) or without oxygen (either skin-packed or gas... more Beef steaks retail-packed with (80% O(2), 20% CO(2)) or without oxygen (either skin-packed or gas-packed (69.6% N(2), 30% CO(2), 0.04% CO or 70% N(2), 30% CO(2))) were compared by consumers in Denmark (n=382), Norway (n=316) and Sweden (n=374). Two pairs of two steaks - one steak packed in a high oxygen atmosphere and one packed without oxygen - were given to the consumers. They were instructed to prepare the steaks at home on two consecutive days, and two persons had to taste each steak. In Denmark, the oxygen-free packing was either gas packing with CO (69.6% N(2), 30% CO(2), 0.04% CO) or without CO (70% N(2), 30% CO(2)), in Norway it was either gas packing with CO (69.6% N(2), 30% CO(2), 0.04% CO) or skin packing, and in Sweden it was either skin packing or gas packing without CO (70% N(2), 30% CO(2)). The meat represented animals that were between 17 and 80 months old (Denmark) and young bulls (Norway and Sweden). Consumers in all three countries clearly preferred steaks packed without oxygen, in terms of overall liking, willingness to pay and their preferred choice of one steak. Furthermore, they preferred the oxygen-free steaks in terms of both overall liking and liking of tenderness, juiciness and flavour. In Sweden, many consumers would pay more than usual for the skin-packed steak, and it was more often chosen as the preferred steak out of the four compared with gas-packed without oxygen. No difference was seen between the two oxygen-free packing methods in Denmark and Norway.

Journal of Agricultural and Food Chemistry, Sep 2, 2006

Inosine monophosphate (IMP) and its degradation products, ribose and hypoxanthine, are all consid... more Inosine monophosphate (IMP) and its degradation products, ribose and hypoxanthine, are all considered to be important constituents in meat flavor formation and development. The present study explored the fate of IMP during the aging of two qualities of pork (pH &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;5.7 and 5.5 &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; pH &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 5.6) and the potential relationship between IMP, hypoxanthine, and sensory attributes of pork registered both as retronasal and basic taste responses in whole meat, meat juice, and the remaining meat residue. During aging the concentration of IMP decreased with a simultaneous increase in the concentrations of inosine, hypoxanthine, and ribose. The rates at which IMP was degraded to inosine and inosine to hypoxanthine during aging were found to be in agreement with the known rate constants of the dephosphorylation of IMP and the hydrolysis of inosine, respectively. Moreover, high-pH pork resulted in a significantly higher concentration of hypoxanthine throughout storage compared with low-pH pork due to an initially higher concentration of IMP in high-pH meat. The sensory analysis showed increasing intensity in bitterness and saltiness of pork as a function of aging, with the intensity being most pronounced in the meat juice. The increasing bitterness of the pork as a function of aging coincided with the higher content of hypoxanthine in these samples, thereby suggesting that degradation of IMP to hypoxanthine might influence pork flavor. In contrast, IMP was associated with nonaged meat and the sensory attributes meaty and brothy.

Journal of the Science of Food and Agriculture, May 22, 2009

BACKGROUND: Marination of beef muscles with brine solutions containing proteolytic enzymes from f... more BACKGROUND: Marination of beef muscles with brine solutions containing proteolytic enzymes from fruit extracts has been shown to tenderize meat. However, the effect of marination with actinidin on tenderness of pork muscles has not been investigated. Tenderness and eating quality of porcine M. biceps femoris was investigated by Warner-Bratzler (WB) shear test and sensory evaluation after injection of brine containing up to 11 g L −1 actinidin-containing kiwi fruit powder and 2, 5 or 9 days of storage. RESULTS: Actinidin decreased WB shear force, increased tenderness and did not affect flavour and juiciness. Injection of 2.8 g L −1 actinidin powder and storage for 2 days resulted in WB shear force values similar to control samples stored for 5 or 9 days. In samples injected with 10 g L −1 actinidin powder, degradation of desmin and percentage of heat-soluble collagen (P < 0.05) increased compared to control samples. Myofibrillar particle size tended to decrease (P < 0.1) with increasing actinidin concentration. No major changes were observed by proteome analysis. Atomic force microscopy showed actinidin-induced damage of endomysium surrounding isolated single muscle fibres. CONCLUSION: Our results indicate that actinidin tenderizes pork M. biceps femoris by affecting both the myofibrils and connective tissue.

Meat Science, Mar 1, 2016

Effect of oxygen level on the oxidative stability of two different retail pork products stored us... more Effect of oxygen level on the oxidative stability of two different retail pork products stored using modified atmosphere packaging (MAP) The characteristics and the oxidative stability of pork steaks and of pork mince were investigated during 2, 5 and 7 days of refrigerated storage using oxygen (O2) levels of 0%, 20%, 50% and 80% in modified atmosphere packaging (MAP). Steaks stored during 7 days were not affected by an increase in O2 concentration, as revealed by lipid and protein oxidation markers. In contrast, the mince was characterised by an altered protein profile, loss of free thiol groups and increased protein oxidation, early during storage. The oxidative stability of pork mince was improved by using intermediate (50%) O2 MAP. The results show that fresh pork products are affected differently by the MAP O2 concentration and strongly indicate that optimisation of MAP based on the retail product type would be of considerable benefit to their oxidative stability.

To optimize eating quality of fresh meat in modified atmosphere packaging (MAP), oxygen exposure ... more To optimize eating quality of fresh meat in modified atmosphere packaging (MAP), oxygen exposure has to be minimized. Oxygen pressure in the headspace is highly responsible for the chemical state of the myoglobin, and through that the colour of the raw meat. Oxygen consumption is muscle specific and has to be balanced with the oxygen content in the gas mixture to achieve an attractive red surface throughout shelf life and to minimize oxidation of proteins and lipids. To establish whether low O2 three-gas MAP (O2, CO2 and N2) could increase sensory quality without compromising shelf life and colour stability, aged strip loin steaks were retail packed in MAP with 30%, 40%, 50% or 70% O2 and 30% CO2. Packing of beef steaks in 30% O2 + 30% CO2 + 40% N2 resulted in more tender, more juicy and less rancid steaks compared with beef steaks packed in traditional MAP (70% O2 + 30% CO2). Three-gas MAP could therefore be a suitable alternative to traditional MAP, maintaining shelf life and colour stability and increasing eating quality.

Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive... more Fresh pork is packed in high oxygen modified atmosphere packaging (MAP) to preserve an attractive bloom colour on the surface of the meat and to extend the microbial shelf life. Unfortunately, the gas composition consisting of 70-80% oxygen (O2) and 20-30% carbon dioxide (CO2) results in less tender and less juicy meat with a more rancid flavour compared with wrapped or vacuum-packed pork. To establish whether three-gas MAP (O2, CO2 and N2) with less oxygen, instead of two-gas MAP, would affect sensory attributes, shelf life and colour stability, enhanced and enhanced + marinated pork chops were packed in MAP with 0%, 40% or 80% O2 and 20% or 40% CO2 an N2 as filler gas. However, it was not possible to optimise the eating quality and shelf life of enhanced pork chops without compromising the acceptance of the raw meat, as seen for fresh pork. By marinating enhanced pork chops, the acceptance limit was extended by two to seven days depending on the gas mixture, and differences in eat...