Effects Of Salt And Nitrite Concentration On
Transcript Of Effects Of Salt And Nitrite Concentration On
University of Nebraska - Lincoln
[email protected] of Nebraska - Lincoln
Theses and Dissertations in Animal Science
Animal Science Department
8-2016
EFFECTS OF SALT AND NITRITE CONCENTRATION ON THE SHELF LIFE OF DELI-STYLE HAM
Regan E. Stanley
University of Nebraska - Lincoln, [email protected]
Follow this and additional works at: http://digitalcommons.unl.edu/animalscidiss Part of the Food Processing Commons, and the Meat Science Commons
Stanley, Regan E., "EFFECTS OF SALT AND NITRITE CONCENTRATION ON THE SHELF LIFE OF DELI-STYLE HAM" (2016). Theses and Dissertations in Animal Science. 119. http://digitalcommons.unl.edu/animalscidiss/119
This Article is brought to you for free and open access by the Animal Science Department at [email protected] of Nebraska - Lincoln. It has been accepted for inclusion in Theses and Dissertations in Animal Science by an authorized administrator of [email protected] of Nebraska - Lincoln.
EFFECTS OF SALT AND NITRITE CONCENTRATION ON THE SHELF LIFE OF DELI-STYLE HAM
By
Regan Elise Stanley
A THESIS
Presented to the Faculty of The Graduate College at the University of Nebraska
In Partial Fulfillment of Requirements For the Degree of Master of Science
Major: Animal Science
Under the Supervision of Professor Gary A. Sullivan
Lincoln, Nebraska
August, 2016
Effects of salt and nitrite concentration on the shelf life of deli-style ham
Regan Elise Stanley, M.S. University of Nebraska, 2016
Advisor: Gary A. Sullivan
Deli-style hams were manufactured to measure the effects of salt and nitrite concentration on shelf life and physicochemical characteristics. Three replications of deli-style ham treatments were manufactured in a 3 x 4 factorial arrangement of salt concentration (0.7%, 1.4%, or 2.1%, meat block basis) and nitrite concentration and source (0 ppm, 100 ppm or 200 ppm sodium nitrite, SN, or 100 ppm sodium nitrite equivalent from pre-converted celery juice powder, CP; Veg Stable 506, Florida Food Products). Salt concentration, water activity, cook yield, and texture profile analysis (TPA) were measured on w 0. Color, pH, residual nitrite, and aerobic and anaerobic plate counts (APC and AnPC, respectively) were measured on weeks 0, 2, 4, 6, 8, 10, 12, 14, and 16. A nitrite by salt interaction (P≤0.05) was found for a*, a/b ratio, ΔE, and hue angle. Treatments without nitrite were less red and more yellow than other treatments. Curing with CP resulted in increased yellowness than SN treatments. An interaction of nitrite and week (P<0.001) was identified for residual nitrite. Residual nitrite values of 0ppm treatments did not change throughout storage, whereas all other treatments declined with increased storage. Excluding interactions above, significant main effects for salt
concentration were identified (P≤0.05). Treatments with 2.1% salt had lower APC than 0.7% salt (P=0.033) and 1.4% salt was similar to both. As nitrite concentration increased, APC was significantly reduced (P<0.001) regardless of nitrite source. Overall, 100 ppm CP and SN were only different for a*, b*, a/b ratio, and hue angle. The 100 ppm CP had lower a* values and a/b ratio, but had higher b*, and hue angle values, than 100 ppm SN. This study suggests 200 ppm SN provides greatest shelf life to deli-style ham. Additionally, 0.7% salt resulted in inferior product quality in many traits compared to 1.4% or 2.1% salt and it is therefore suggested to use amounts greater than 0.7% salt when formulating deli-style ham. Keywords: Salt, Nitrite, Ham, Shelf life.
iv Copyright 2016, Regan Elise Stanley
v
Acknowledgements I would like to thank Dr. Gary Sullivan for the opportunity of being his graduate
student. Dr. Sullivan has given me many opportunities to learn more about Meat Science and newer industry technologies in a hands on manner, which suits me best. I would also like to thank Dr. Dennis Burson and Dr. Samodha Fernando for being members of my committee and preparing me to be successful in my future endeavors in meat science. I also appreciate all other faculty members that contributed to my graduate school experiences and my education. Calvin Schrock was a great help by assisting me whenever necessary for my project, or any projects I helped with. Tommi Jones assisted me in the completion of my lab work in the meat science chemistry lab, and provided guidance to make my lab days quite enjoyable. Sherri Pitchie has always been able to help me with office work and any other requests I had.
Without question, I must thank my friends and family for encouraging me over the past two years. The support I have received from my family, especially my husband and parents, has been phenomenal and given me the endurance to continue on when I didn’t think I had it in me. Additionally, I cannot thank my dad enough for making the drive to help me move to Lincoln. I also appreciate the help and friendship from all of the graduate students: Brandy, Michael, Joe, Kelly, Ashley, Hope, Emery, Sara, Chad, and Kathy. Their humor has kept me going throughout this process.
vi
TABLE OF CONTENTS
TITLE PAGE.....................................................................................................................i ABSTRACT.......................................................................................................................ii COPYRIGHT PAGE.......................................................................................................iv ACKNOWLEDGEMENTS..............................................................................................v TABLE OF CONTENTS.................................................................................................vi 1. INTRODUCTION.........................................................................................................1 2. REVIEW OF LITERATURE.......................................................................................3 2.1 History of Meat Preservation and Curing.................................................................3 2.2 Chemistry of Nitrate, Nitrite, and Nitric Oxide........................................................5 2.3 Nitric Oxide and Myoglobin.......................................................................................7 2.4 Functional Ingredients and their Effects on Curing.................................................8 2.5 Cured Meat Characteristics......................................................................................12 2.6 Microbial Shelf Life of Processed Meats.................................................................17 2.7 Health Impacts of Nitrite and Nitric Oxide.............................................................18 2.8 Salt Reduction in Meat..............................................................................................20 2.9 Alternative Meat Curing...........................................................................................21 2.10 Summary...................................................................................................................25 3. MATERIALS AND METHODS................................................................................27
3.1 Treatment and Product Formulations of Hams..........................................27 3.2 Deli-Style Ham Manufacture........................................................................28 3.3 Physiochemical Analyses...............................................................................29
3.3.1 Objective Color...............................................................................29 3.3.2 Water Activity.................................................................................30 3.3.3 Salt Concentration..........................................................................30 3.3.4 pH.....................................................................................................31 3.3.5 Residual Nitrite...............................................................................31 3.3.6 Proximate Analysis.........................................................................33 3.3.7 Texture Profile Analysis.................................................................33 3.4 Microbiological Analyses...............................................................................34 3.4.1 Anaerobic Plate Count...................................................................34 3.4.2 Aerobic Plate Count........................................................................35 4. LITERATURE CITED...............................................................................................36 5. EFFECTS OF SALT AND NITRITE CONCENTRATION ON THE SHELF LIFE OF DELI-STYLE HAM........................................................................................46 5.1 Abstract...........................................................................................................47 5.2 Introduction....................................................................................................49 5.3 Materials and Methods..................................................................................51 5.3.1 Treatments and Product Formulations of Hams.........................51 5.3.2 Deli-Style Ham Manufacture.........................................................52 5.3.3 Physicochemical Analyses..............................................................53
5.3.3.1 Objective Color................................................................53 5.3.3.2 Water Activity..................................................................54
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5.3.3.3 Salt Concentration...........................................................54 5.3.3.4 pH......................................................................................54 5.3.3.5 Residual Nitrite................................................................55 5.3.3.6 Texture Profile Analysis..................................................56 5.3.4 Microbiological Analysis................................................................57 5.3.5 Statistical Analysis..........................................................................57 5.4 Results.............................................................................................................58 5.4.1 Objective Color...............................................................................58 5.4.2 Water activity, Cooking Yield, Measured Salt Concentration, and Proximate Composition....................................................................60 5.4.3 Texture Profile Analysis.................................................................60 5.4.4 pH.....................................................................................................61 5.4.5 Residual Nitrite...............................................................................61 5.4.6 Microbiological Analysis................................................................62 5.5 Discussion.......................................................................................................62 5.6 References.......................................................................................................69 6. FIGURES AND TABLES...........................................................................................72 7. APPENDICES..............................................................................................................91
1
1. INTRODUCTION Today’s consumers are becoming increasingly interested in the process of manufacturing the food they eat. They are concerned with the nutritive value of their food, as well as the long-term effect the food that they eat has on their wellness. Additionally, consumers have the idea that there are negative health problems associated with consuming some ingredients such as nitrates and nitrites, and more recently, red and processed meats altogether. Health related issues, such as heart disease and high blood pressure, have been related to high levels of sodium in the American diet, so there is a large push to reduce sodium intake to combat the vast health problems. Reducing salt is known to lower blood pressure, aiding in reduction of health problems. In response, meat scientists and the meat industry is working diligently to manufacture reduced sodium products, and to slowly reduce sodium in products, which may or may not be labeled as reduced sodium. Due to the functionality of salt, it becomes difficult to remove much of the salt present in these products, and is therefore a challenge for the meat industry as a whole. Salt is necessary for adequate product cohesion and stability of emulsions to provide acceptable meat products. Salt also aids in palatability of the product and improvement of the microbial shelf life of products by shifting microbial populations towards lactic acid producing bacteria. Another ingredient of high importance and consumer concern is nitrite. Consumers want a clean label product, so natural alternatives must be used to achieve their desire, but we must also provide the same safety as products cured with sodium nitrite. Nitrite is known for its ability to inhibit Clostridium botulinum. Typically in natural cured meats, amount of nitrite equivalent present is much lower due to the use of
2
pre-converted celery juice powder. Celery powder has negative flavor characteristics if added at the same level as sodium nitrite. The combination of lower nitrite and limitations for natural antimicrobials in these products, along with reduced sodium levels may potentially provide a more favorable environment for pathogens to survive when compared to conventionally cured meats. In order to further understand the safety of these products, we must study the impact of reduced sodium and nitrite concentration and source on the shelf life and quality characteristics on these products.
This study compared physiochemical qualities and microbial integrity of delistyle ham produced with salt or nitrite concentration. This study identified how salt and nitrite concentrations affect the quality characteristics of deli-style ham. Additionally, how salt and nitrite concentration affect the growth of natural spoilage flora of sliced deli-style ham was also discovered.
[email protected] of Nebraska - Lincoln
Theses and Dissertations in Animal Science
Animal Science Department
8-2016
EFFECTS OF SALT AND NITRITE CONCENTRATION ON THE SHELF LIFE OF DELI-STYLE HAM
Regan E. Stanley
University of Nebraska - Lincoln, [email protected]
Follow this and additional works at: http://digitalcommons.unl.edu/animalscidiss Part of the Food Processing Commons, and the Meat Science Commons
Stanley, Regan E., "EFFECTS OF SALT AND NITRITE CONCENTRATION ON THE SHELF LIFE OF DELI-STYLE HAM" (2016). Theses and Dissertations in Animal Science. 119. http://digitalcommons.unl.edu/animalscidiss/119
This Article is brought to you for free and open access by the Animal Science Department at [email protected] of Nebraska - Lincoln. It has been accepted for inclusion in Theses and Dissertations in Animal Science by an authorized administrator of [email protected] of Nebraska - Lincoln.
EFFECTS OF SALT AND NITRITE CONCENTRATION ON THE SHELF LIFE OF DELI-STYLE HAM
By
Regan Elise Stanley
A THESIS
Presented to the Faculty of The Graduate College at the University of Nebraska
In Partial Fulfillment of Requirements For the Degree of Master of Science
Major: Animal Science
Under the Supervision of Professor Gary A. Sullivan
Lincoln, Nebraska
August, 2016
Effects of salt and nitrite concentration on the shelf life of deli-style ham
Regan Elise Stanley, M.S. University of Nebraska, 2016
Advisor: Gary A. Sullivan
Deli-style hams were manufactured to measure the effects of salt and nitrite concentration on shelf life and physicochemical characteristics. Three replications of deli-style ham treatments were manufactured in a 3 x 4 factorial arrangement of salt concentration (0.7%, 1.4%, or 2.1%, meat block basis) and nitrite concentration and source (0 ppm, 100 ppm or 200 ppm sodium nitrite, SN, or 100 ppm sodium nitrite equivalent from pre-converted celery juice powder, CP; Veg Stable 506, Florida Food Products). Salt concentration, water activity, cook yield, and texture profile analysis (TPA) were measured on w 0. Color, pH, residual nitrite, and aerobic and anaerobic plate counts (APC and AnPC, respectively) were measured on weeks 0, 2, 4, 6, 8, 10, 12, 14, and 16. A nitrite by salt interaction (P≤0.05) was found for a*, a/b ratio, ΔE, and hue angle. Treatments without nitrite were less red and more yellow than other treatments. Curing with CP resulted in increased yellowness than SN treatments. An interaction of nitrite and week (P<0.001) was identified for residual nitrite. Residual nitrite values of 0ppm treatments did not change throughout storage, whereas all other treatments declined with increased storage. Excluding interactions above, significant main effects for salt
concentration were identified (P≤0.05). Treatments with 2.1% salt had lower APC than 0.7% salt (P=0.033) and 1.4% salt was similar to both. As nitrite concentration increased, APC was significantly reduced (P<0.001) regardless of nitrite source. Overall, 100 ppm CP and SN were only different for a*, b*, a/b ratio, and hue angle. The 100 ppm CP had lower a* values and a/b ratio, but had higher b*, and hue angle values, than 100 ppm SN. This study suggests 200 ppm SN provides greatest shelf life to deli-style ham. Additionally, 0.7% salt resulted in inferior product quality in many traits compared to 1.4% or 2.1% salt and it is therefore suggested to use amounts greater than 0.7% salt when formulating deli-style ham. Keywords: Salt, Nitrite, Ham, Shelf life.
iv Copyright 2016, Regan Elise Stanley
v
Acknowledgements I would like to thank Dr. Gary Sullivan for the opportunity of being his graduate
student. Dr. Sullivan has given me many opportunities to learn more about Meat Science and newer industry technologies in a hands on manner, which suits me best. I would also like to thank Dr. Dennis Burson and Dr. Samodha Fernando for being members of my committee and preparing me to be successful in my future endeavors in meat science. I also appreciate all other faculty members that contributed to my graduate school experiences and my education. Calvin Schrock was a great help by assisting me whenever necessary for my project, or any projects I helped with. Tommi Jones assisted me in the completion of my lab work in the meat science chemistry lab, and provided guidance to make my lab days quite enjoyable. Sherri Pitchie has always been able to help me with office work and any other requests I had.
Without question, I must thank my friends and family for encouraging me over the past two years. The support I have received from my family, especially my husband and parents, has been phenomenal and given me the endurance to continue on when I didn’t think I had it in me. Additionally, I cannot thank my dad enough for making the drive to help me move to Lincoln. I also appreciate the help and friendship from all of the graduate students: Brandy, Michael, Joe, Kelly, Ashley, Hope, Emery, Sara, Chad, and Kathy. Their humor has kept me going throughout this process.
vi
TABLE OF CONTENTS
TITLE PAGE.....................................................................................................................i ABSTRACT.......................................................................................................................ii COPYRIGHT PAGE.......................................................................................................iv ACKNOWLEDGEMENTS..............................................................................................v TABLE OF CONTENTS.................................................................................................vi 1. INTRODUCTION.........................................................................................................1 2. REVIEW OF LITERATURE.......................................................................................3 2.1 History of Meat Preservation and Curing.................................................................3 2.2 Chemistry of Nitrate, Nitrite, and Nitric Oxide........................................................5 2.3 Nitric Oxide and Myoglobin.......................................................................................7 2.4 Functional Ingredients and their Effects on Curing.................................................8 2.5 Cured Meat Characteristics......................................................................................12 2.6 Microbial Shelf Life of Processed Meats.................................................................17 2.7 Health Impacts of Nitrite and Nitric Oxide.............................................................18 2.8 Salt Reduction in Meat..............................................................................................20 2.9 Alternative Meat Curing...........................................................................................21 2.10 Summary...................................................................................................................25 3. MATERIALS AND METHODS................................................................................27
3.1 Treatment and Product Formulations of Hams..........................................27 3.2 Deli-Style Ham Manufacture........................................................................28 3.3 Physiochemical Analyses...............................................................................29
3.3.1 Objective Color...............................................................................29 3.3.2 Water Activity.................................................................................30 3.3.3 Salt Concentration..........................................................................30 3.3.4 pH.....................................................................................................31 3.3.5 Residual Nitrite...............................................................................31 3.3.6 Proximate Analysis.........................................................................33 3.3.7 Texture Profile Analysis.................................................................33 3.4 Microbiological Analyses...............................................................................34 3.4.1 Anaerobic Plate Count...................................................................34 3.4.2 Aerobic Plate Count........................................................................35 4. LITERATURE CITED...............................................................................................36 5. EFFECTS OF SALT AND NITRITE CONCENTRATION ON THE SHELF LIFE OF DELI-STYLE HAM........................................................................................46 5.1 Abstract...........................................................................................................47 5.2 Introduction....................................................................................................49 5.3 Materials and Methods..................................................................................51 5.3.1 Treatments and Product Formulations of Hams.........................51 5.3.2 Deli-Style Ham Manufacture.........................................................52 5.3.3 Physicochemical Analyses..............................................................53
5.3.3.1 Objective Color................................................................53 5.3.3.2 Water Activity..................................................................54
vii
5.3.3.3 Salt Concentration...........................................................54 5.3.3.4 pH......................................................................................54 5.3.3.5 Residual Nitrite................................................................55 5.3.3.6 Texture Profile Analysis..................................................56 5.3.4 Microbiological Analysis................................................................57 5.3.5 Statistical Analysis..........................................................................57 5.4 Results.............................................................................................................58 5.4.1 Objective Color...............................................................................58 5.4.2 Water activity, Cooking Yield, Measured Salt Concentration, and Proximate Composition....................................................................60 5.4.3 Texture Profile Analysis.................................................................60 5.4.4 pH.....................................................................................................61 5.4.5 Residual Nitrite...............................................................................61 5.4.6 Microbiological Analysis................................................................62 5.5 Discussion.......................................................................................................62 5.6 References.......................................................................................................69 6. FIGURES AND TABLES...........................................................................................72 7. APPENDICES..............................................................................................................91
1
1. INTRODUCTION Today’s consumers are becoming increasingly interested in the process of manufacturing the food they eat. They are concerned with the nutritive value of their food, as well as the long-term effect the food that they eat has on their wellness. Additionally, consumers have the idea that there are negative health problems associated with consuming some ingredients such as nitrates and nitrites, and more recently, red and processed meats altogether. Health related issues, such as heart disease and high blood pressure, have been related to high levels of sodium in the American diet, so there is a large push to reduce sodium intake to combat the vast health problems. Reducing salt is known to lower blood pressure, aiding in reduction of health problems. In response, meat scientists and the meat industry is working diligently to manufacture reduced sodium products, and to slowly reduce sodium in products, which may or may not be labeled as reduced sodium. Due to the functionality of salt, it becomes difficult to remove much of the salt present in these products, and is therefore a challenge for the meat industry as a whole. Salt is necessary for adequate product cohesion and stability of emulsions to provide acceptable meat products. Salt also aids in palatability of the product and improvement of the microbial shelf life of products by shifting microbial populations towards lactic acid producing bacteria. Another ingredient of high importance and consumer concern is nitrite. Consumers want a clean label product, so natural alternatives must be used to achieve their desire, but we must also provide the same safety as products cured with sodium nitrite. Nitrite is known for its ability to inhibit Clostridium botulinum. Typically in natural cured meats, amount of nitrite equivalent present is much lower due to the use of
2
pre-converted celery juice powder. Celery powder has negative flavor characteristics if added at the same level as sodium nitrite. The combination of lower nitrite and limitations for natural antimicrobials in these products, along with reduced sodium levels may potentially provide a more favorable environment for pathogens to survive when compared to conventionally cured meats. In order to further understand the safety of these products, we must study the impact of reduced sodium and nitrite concentration and source on the shelf life and quality characteristics on these products.
This study compared physiochemical qualities and microbial integrity of delistyle ham produced with salt or nitrite concentration. This study identified how salt and nitrite concentrations affect the quality characteristics of deli-style ham. Additionally, how salt and nitrite concentration affect the growth of natural spoilage flora of sliced deli-style ham was also discovered.