How Temperature Effects Food Decay
|
|
|
Background Paper
For my Knights of Science project, I have chosen a project concerning the field of food science. Food science is a field using biology and chemistry to study food from harvest to consumption. Understanding and developing this process is essential to improving safety, quality, and preservation of food. Food science is a growing field, with an expected growth of six percent over the next ten years, a faster than average growth. Many students choose food science to study for projects and experiments each school year, some traditional food science experiments may include topics like measuring levels of vitamins or fats in different foods or measuring the effectiveness of different food preservation methods.
Have you ever been looking deep in the refrigerator for a snack and accidentally stumbled upon last month’s leftovers in the very back? It probably didn’t look very appetizing and may have even been covered in mold. This is caused by food decay. Food decay is the process by which food becomes unsafe or undesirable to eat. This can be due to microbial growth, enzyme activity, or chemical reactions. I will be studying decay in beans, a plant based food. Decay in these foods is usually caused by bacteria and fungi naturally existing in the environment. These organisms break down matter in the food, leading to changes in color, texture, odor, and nutritional value. Physical factors affecting food decay include temperature, moisture, oxygen, and light.
Food decay can look different depending on what process is causing it. Spoilage caused by microorganisms usually occurs at room temperature and can make food taste, smell, or look unpleasant. This kind of spoilage can also be pathogenic, causing no change.
Enzymes are naturally occurring in all foods and contribute to the ripening process. Enzymic spoilage happens when enzymes break down and can cause a change in color, firmness, and texture. Other common causes of decay include air, light, time, pests (insects, parasites, or rodents), or physical damage.
My project will involve investigating the effect of temperature on food decay. Warmer temperatures generally speed up microbial growth and moisture loss, while colder temperatures do the opposite, slowing or stopping the process. The United States Department of Agriculture (USDA) refers to the range of temperatures between forty degrees Fahrenheit and one hundred-forty degrees Fahrenheit as the “danger zone”. While in these conditions, bacteria growth can double in number in as few as twenty minutes. The USDA “advises consumers to never leave food out of refrigeration over 2 hours. If the temperature is above 90 °F, food should not be left out more than 1 hour.” Eating spoiled food can lead to food poisoning, symptoms and durations vary based on what kind of bacteria you consumed. Commonly contracted varieties of food poisoning are Staphylococcus Aureus, Vibrio, Clostridium Perfringens, Salmonella, and Norovirus. Food poisoning can lead to other serious problems like dehydration, kidney issues, or nervous system damage. It is very important to ensure that you are safely storing your food. If you ever have food that you suspect to be spoiled, the USDA has a hotline that you can call to consult an expert on if the food may have been spoiled.
Having studied the components of my experiment, my teachers and I have decided that using canned beans rather than dried beans would yield the best results. Canned beans are usually packed using preservatives and flavors to help them last longer and retain their freshness, so when studying decay it is important to choose beans that are packaged as simply as possible.
In conclusion, there are several factors affecting food decay, each presenting different characteristics and effects. It is important to understand food science and how it affects daily life, as what you consume can have critical consequences.
Have you ever been looking deep in the refrigerator for a snack and accidentally stumbled upon last month’s leftovers in the very back? It probably didn’t look very appetizing and may have even been covered in mold. This is caused by food decay. Food decay is the process by which food becomes unsafe or undesirable to eat. This can be due to microbial growth, enzyme activity, or chemical reactions. I will be studying decay in beans, a plant based food. Decay in these foods is usually caused by bacteria and fungi naturally existing in the environment. These organisms break down matter in the food, leading to changes in color, texture, odor, and nutritional value. Physical factors affecting food decay include temperature, moisture, oxygen, and light.
Food decay can look different depending on what process is causing it. Spoilage caused by microorganisms usually occurs at room temperature and can make food taste, smell, or look unpleasant. This kind of spoilage can also be pathogenic, causing no change.
Enzymes are naturally occurring in all foods and contribute to the ripening process. Enzymic spoilage happens when enzymes break down and can cause a change in color, firmness, and texture. Other common causes of decay include air, light, time, pests (insects, parasites, or rodents), or physical damage.
My project will involve investigating the effect of temperature on food decay. Warmer temperatures generally speed up microbial growth and moisture loss, while colder temperatures do the opposite, slowing or stopping the process. The United States Department of Agriculture (USDA) refers to the range of temperatures between forty degrees Fahrenheit and one hundred-forty degrees Fahrenheit as the “danger zone”. While in these conditions, bacteria growth can double in number in as few as twenty minutes. The USDA “advises consumers to never leave food out of refrigeration over 2 hours. If the temperature is above 90 °F, food should not be left out more than 1 hour.” Eating spoiled food can lead to food poisoning, symptoms and durations vary based on what kind of bacteria you consumed. Commonly contracted varieties of food poisoning are Staphylococcus Aureus, Vibrio, Clostridium Perfringens, Salmonella, and Norovirus. Food poisoning can lead to other serious problems like dehydration, kidney issues, or nervous system damage. It is very important to ensure that you are safely storing your food. If you ever have food that you suspect to be spoiled, the USDA has a hotline that you can call to consult an expert on if the food may have been spoiled.
Having studied the components of my experiment, my teachers and I have decided that using canned beans rather than dried beans would yield the best results. Canned beans are usually packed using preservatives and flavors to help them last longer and retain their freshness, so when studying decay it is important to choose beans that are packaged as simply as possible.
In conclusion, there are several factors affecting food decay, each presenting different characteristics and effects. It is important to understand food science and how it affects daily life, as what you consume can have critical consequences.
Investigation Paper
My hypothesis for this project is that heat has an effect on the rate of decay. I believe that food items kept in warmer environments will decay faster than those kept in a cold environment. To test this, I will be observing the rate of decay for three different samples of beans, one left in a room temperature environment, one left in a cold environment, and one left in a warm environment. I will use the results from each set to determine if there is a difference in the speed or way in which they decay.
Decomposition occurs whenever bacteria and other microorganisms break down organic matter. These microorganisms depend on proteins called enzymes to function. Reactions happen whenever the enzymes collide, more collisions create faster reactions, and fewer collisions create slower reactions. Temperature has a large effect on enzyme activity, and warmer temperatures increase the amount of energy and collisions that occur. Another factor affecting these enzymes and decay is air flow. Increased oxygen availability is important for encouraging decomposers and the chemical reactions associated with them.
The materials needed for this project are as follows:
I will be using pinto beans for this experiment. I chose to use pinto beans partially due to the high availability and the fact I already had plenty, and partly because their color, shape, and texture will make it easy to observe signs of decay. After purchasing the pinto beans, I will open the can and place equal amounts of both beans and the liquid from the can in nine ziploc bags. It is important that each bag has some of the liquid from the can in it, as the beans will decay faster in liquid allowing for better observation. I will divide the bags into three groups of three. I will be testing so many different samples to ensure that my experiment is accurate and repeatable. Three bags will be kept in my refrigerator, at a temperature of thirty-nine degrees Fahrenheit, this will be to test the rate of decay in cold beans. Three of the bags will be kept under a heat lamp to test the effect of heat on the beans. Finally three of the bags will be left in a room temperature environment. These bags will be acting as the control group, as they are facing neither abnormally cold temperatures nor abnormally warm temperatures. When placing the samples I will be sure to keep the plastic bags open enough that air can get in and flow easily into possibly accelerate the rate of decomposition.
Throughout this experiment, I will regularly check on the beans (one to two times a day), and observe any changes and document them with photos. At the end of my experiment, I will have photos demonstrating any change in qualities like appearance, texture, and firmness for the whole time the beans are left.
To measure the results, I will look back at the photos and the current state of the beans and inspect them to find any apparent differences in the rate of decomposition between the three groups. I believe that the beans kept in the warm environment will decay faster than those kept in a cold environment, as the warmer temperatures will create better conditions to encourage a faster rate of decay. Likewise, the cold temperatures of the refrigerator will create an environment discouraging decay.
Decomposition occurs whenever bacteria and other microorganisms break down organic matter. These microorganisms depend on proteins called enzymes to function. Reactions happen whenever the enzymes collide, more collisions create faster reactions, and fewer collisions create slower reactions. Temperature has a large effect on enzyme activity, and warmer temperatures increase the amount of energy and collisions that occur. Another factor affecting these enzymes and decay is air flow. Increased oxygen availability is important for encouraging decomposers and the chemical reactions associated with them.
The materials needed for this project are as follows:
- Pinto beans
- Ziploc bags
- Heat lamp
- Refrigerator
- Sharpie (for labeling)
- Camera or phone for documentation
I will be using pinto beans for this experiment. I chose to use pinto beans partially due to the high availability and the fact I already had plenty, and partly because their color, shape, and texture will make it easy to observe signs of decay. After purchasing the pinto beans, I will open the can and place equal amounts of both beans and the liquid from the can in nine ziploc bags. It is important that each bag has some of the liquid from the can in it, as the beans will decay faster in liquid allowing for better observation. I will divide the bags into three groups of three. I will be testing so many different samples to ensure that my experiment is accurate and repeatable. Three bags will be kept in my refrigerator, at a temperature of thirty-nine degrees Fahrenheit, this will be to test the rate of decay in cold beans. Three of the bags will be kept under a heat lamp to test the effect of heat on the beans. Finally three of the bags will be left in a room temperature environment. These bags will be acting as the control group, as they are facing neither abnormally cold temperatures nor abnormally warm temperatures. When placing the samples I will be sure to keep the plastic bags open enough that air can get in and flow easily into possibly accelerate the rate of decomposition.
Throughout this experiment, I will regularly check on the beans (one to two times a day), and observe any changes and document them with photos. At the end of my experiment, I will have photos demonstrating any change in qualities like appearance, texture, and firmness for the whole time the beans are left.
To measure the results, I will look back at the photos and the current state of the beans and inspect them to find any apparent differences in the rate of decomposition between the three groups. I believe that the beans kept in the warm environment will decay faster than those kept in a cold environment, as the warmer temperatures will create better conditions to encourage a faster rate of decay. Likewise, the cold temperatures of the refrigerator will create an environment discouraging decay.
Conclusion
My experiment was to test the effect of temperature on the decomposition of pinto beans. I tested the effect of a colder temperature and the effect of a warmer temperature, and kept some room temperature as a control group. My hypothesis was that the beans stored in a warmer environment would decompose faster. I concluded that the first set of= beans to show signs of decomposition would be in the environment that best supported decay.
To set up my experiment, I made up several ziploc bags containing pinto beans and the juice from the can. I created three different environments, each with a different temperature. My first group was to be kept in a colder environment, so I left this set in my refrigerator at home. My second set was to be kept at room temperature, so I left them on a counter in the corner of my kitchen. Lastly, the third set was to be kept in a warmer environment, so I left them next to a heat lamp. If my hypothesis was correct, the group of beans kept in the warm environment under the heat lamp would start to show signs of decomposition first.
I checked the bags of pinto beans each night, closely checking to see if I could spot any signs of decomposition. I took pictures nightly as well hoping to capture any progression of decay that might have occured. As my experiment progressed, I started to worry as I had not yet noticed any changes in the beans towards the end of the time I had allotted for my experiment. I held out hope that I would have some results, but sadly, the beans showed little to no signs of any change, let alone decomposition. This lack of results was disappointing, and may have been due to an error I made when designing my experiment. However, I am still holding out hope, and at the time of writing this paper, the beans are still sitting in my refrigerator, under the heat lamp, and in my kitchen.
If I were to repeat this experiment, there are a few things that I think I would change in order for it to potentially yield better results. Firstly, I would probably change the way I set up the beans. While I did leave the bags open to allow for airflow, there is a good chance that the bags limited airflow regardless. This could have hindered the process. I believe that if I hadn’t set them in Ziploc bags, and instead placed them in something else, maybe a paper towel. I once tried to grow lemon seeds in a paper towel and instead of germinating, the seeds began to rot. I wonder if using the same method could’ve yielded my desired results. Another thing I could have done differently to potentially have different results is to have left the beans for longer. I allowed about three weeks for my experiment, but perhaps if I had set up the beans and began the experiment earlier, leaving them with more time, it would have opened up the possibility for observable results. Lastly, maybe the temperature difference in the beans was not great enough to provoke any real difference in the rate of decomposition. The refrigerator left the beans at thirty-nine degrees Fahrenheit, which is considerably colder than room temperature, but maybe using another, stronger source of heat for the warm beans would have yielded better results for the experiment.
In conclusion, My experiment did not yield the results that I expected it to. I think that there are some factors that I could have changed to have better encouraged a quicker decomposition. Ultimately, I am glad I chose this experiment. I learned a lot about the processes of decay and decomposition. Through my research I learned about food science (a field I previously knew very very little about), and why certain methods of food preservation are used. I also learned about the bacteria and enzymes behind the chemical process of decomposition. Even though I did not witness dramatic decay, I now understand valuable concepts related to the food we eat each and every day.
To set up my experiment, I made up several ziploc bags containing pinto beans and the juice from the can. I created three different environments, each with a different temperature. My first group was to be kept in a colder environment, so I left this set in my refrigerator at home. My second set was to be kept at room temperature, so I left them on a counter in the corner of my kitchen. Lastly, the third set was to be kept in a warmer environment, so I left them next to a heat lamp. If my hypothesis was correct, the group of beans kept in the warm environment under the heat lamp would start to show signs of decomposition first.
I checked the bags of pinto beans each night, closely checking to see if I could spot any signs of decomposition. I took pictures nightly as well hoping to capture any progression of decay that might have occured. As my experiment progressed, I started to worry as I had not yet noticed any changes in the beans towards the end of the time I had allotted for my experiment. I held out hope that I would have some results, but sadly, the beans showed little to no signs of any change, let alone decomposition. This lack of results was disappointing, and may have been due to an error I made when designing my experiment. However, I am still holding out hope, and at the time of writing this paper, the beans are still sitting in my refrigerator, under the heat lamp, and in my kitchen.
If I were to repeat this experiment, there are a few things that I think I would change in order for it to potentially yield better results. Firstly, I would probably change the way I set up the beans. While I did leave the bags open to allow for airflow, there is a good chance that the bags limited airflow regardless. This could have hindered the process. I believe that if I hadn’t set them in Ziploc bags, and instead placed them in something else, maybe a paper towel. I once tried to grow lemon seeds in a paper towel and instead of germinating, the seeds began to rot. I wonder if using the same method could’ve yielded my desired results. Another thing I could have done differently to potentially have different results is to have left the beans for longer. I allowed about three weeks for my experiment, but perhaps if I had set up the beans and began the experiment earlier, leaving them with more time, it would have opened up the possibility for observable results. Lastly, maybe the temperature difference in the beans was not great enough to provoke any real difference in the rate of decomposition. The refrigerator left the beans at thirty-nine degrees Fahrenheit, which is considerably colder than room temperature, but maybe using another, stronger source of heat for the warm beans would have yielded better results for the experiment.
In conclusion, My experiment did not yield the results that I expected it to. I think that there are some factors that I could have changed to have better encouraged a quicker decomposition. Ultimately, I am glad I chose this experiment. I learned a lot about the processes of decay and decomposition. Through my research I learned about food science (a field I previously knew very very little about), and why certain methods of food preservation are used. I also learned about the bacteria and enzymes behind the chemical process of decomposition. Even though I did not witness dramatic decay, I now understand valuable concepts related to the food we eat each and every day.
