Click "I'M READY!" to learn and understand the role of chemistry and microbiology in creating food aroma.
I'm READY!
what is food aroma?
Food aroma plays a crucial role in how people perceive and experience food through smell. Although food aroma may seem like an ordinary sensory experience, it is most likely the result of complex chemical and micrbiological processes, These aromas are also produced through intrecate intricate interactions at microbial and molecular level. From the pungent odor of garlic, smell of freshly baked homemade bread, or the strong smell of cheese. Hence, understanding how chemical reactions and microbial metabolism make volatile organic compounds (VOCs) can show the significant role of chemistry and micrbiology in producing food aroma.
continue
Press any color to learn about the different process of chemical reactions of food aroma!
Chemical reaction in food aroma
Chemical reaction is one of the main contributors to food aroma since it occurs in any physical processes, such as cooking because heat is applied during this process.
Click here
volatile organic compounds
volatile organic compounds and its different types
Figure 1. From "Testing for Volatile Organic Compounds (VOCs) in Food" by Eurofins, https://www.eurofins.in/food-testing/blog/testing-for-volatile-organic-compounds-vocs-in-food/. Copyright 2016 by Eurofins Scientific.
Volatile organic compounds (VOCs) are chemical compounds that will evaporate in room temperature due to high pressure, which then reach the sensory receptors that help detect and perceive different aromas.
types of volatile organic compounds:
Esters - Fruity or sweet aromas commonly found in fruits.
Ketones - Creamy scents found in many dairy products.
Alcohol - Fermented aroma found in wine or beer.
Aldehydes - Sharp and fresh scents found in citrus and several spices.
Sulfure-containing compounds - pungent or strong odors that comes from onion, broccoli, or garlic.
Next
Did you know?
SPEAKING OF SULFUR-CONTAINING COMPOUNDS!
Figure 2. From "Garlic bioactive substances and their therapeutic applications for improving human health: a comprehensive review
" byFrontiers, https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2024.1277074/full. Copyright 2026 by Frontiers Media SA.
When garlic is crushed or minced, enzymes convert the sulfur-containing compounds into a precursor molecular substance. A precursor molecule is an odorless, non-protein amino acid stored in the cytoplasm of an inatct garlic cell. Hence, once garlic is crushed, it releases a strong odor because the non-protein amino acid of intact garlic cell becomes unstable. (Jain & Apitz-Castro, 1993). This process exhibits how chemical reactions can occur even without heat, which shows that it can also rely on enzymatic activity to create aromatic compounds. Additionally, these sulfur-based VOCs are highly potent, highlighting how even small molecular changes from a crushed or cut garlic can have a significant sensory impact. Together, these examples emphasize that chemical reactions are important in producing the compounds responsible for food aroma.
click here
maillard reaction
what is a Maillard reaction?
Figure 3. From "Food Processing: The Influence of the Maillard Reaction on Immunogenicity and Allergenicity of Food Proteins" by Wageningen University & Research,https://www.researchgate.net/publication/318917156_Food_Processing_The_Influence_of_the_Maillard_Reaction_on_Immunogenicity_and_Allergenicity_of_Food_Proteins?_tp=eyJjb250ZXh0Ijp7ImZpcnN0UGFnZSI6Il9kaXJlY3QiLCJwYWdlIjoiX2RpcmVjdCJ9fQ. Copyright 2017 by ResearchGate.
Maillard reaction occurs when reducing sugars interact with amino acids under heat, which is responsible for producing various kinds of compounds that allow the browning effect of cooked foods and creating rich aromas. These compounds also contain pyrazines, which produces the nutty and roasted aromas in many foods (Swiss Education Group, 2025). Aside from that, maillard reaction is a type of chemical reaction that demonstrates how chemical transformations in food can generate new molecules that evaporates in the air, which form volatile organic compounds that are detected by the human olfactory receptors (American Chemical Society, 2013). Therefore, as a result, foods like seared meat, baked bread, and coffee develop their own characteristic aroma.
click here
fun fact!
Scientific methods involving chemical reactions have been developed to analyze and classify the compounds of aroma. For instance, during the 1940s, Keene Dimick was one of the earliest flavor chemists at the Western Regional Research Center in USDA. He used an analytical technique through gas chromatography to find out what makes the strawberry smell the way it does. His goal was to learn what gave off its scent in order to improve processed foods in this era. Later during his research, he discovered that it was the strawberry essence that gives the scent of a strawberry. Methods were composed of evaporation, distillation, and extraction technologies. Later on, he published his research findings in 1956.
Figure 4. From "The Chemistry of Flavor: The Flavor Researchers of USDA's Western Regional Research Center
" by U.S. Department of Agriculture, https://www.nal.usda.gov/collections/stories/chemistry-of-flavor. Copyright 2013 by National Agricultural Library of the U.S. Department of Agriculture.
done
you'VE unlocked your knowledge ABOUT
THE chemical reaction in food aroma
now that you've finished this level, You may proceed and click continue.
continue
MENU
level
Chemical Reactions
Start
Microbial Metabolism
End
Microbial metabolism...
Refers to the biochemical process that shows how microorganisms such as yeast, bacteria, and mold that breaks down nutrients to produce energy. According to a journal article from the National Library of Medicine, the author notes that during the process of microbial metabolism, microbes generate many byproducts, which are composed volatile organic compounds (VOCs) that contribute to aroma (Kumar Verma et al., 2022). Moreover, fermentation is a controlled application of microbial metabolism and is most likely used in many foods like baked goods and wine. These type of foods will eventually develop unique odors due to the specific metabolic actvities of microorganisms that are involved within the process.
What exactly is microbial metabolism?
click here
CHEESE PRODUCTION
microbial metabolism and its relation to cheese aroma
The changes in cheese is determined by the presence of lactic acid bacteria (LAB) during its fermentation process. These bacteria ferment milk into lactic acid, which causes the milk to coagulate or turn from its liquid form into a solid substance, turning it into whey and curds (Drake & McKilip, 2000). Furthermore, these bacteria also continue to produce enzymes that break down proteins and fats, transforming molecules into volatile organic compounds that create distinct aromas of several cheeses. The unique characteristics of different microbial species also contribute to the wide range of cheese aromas because based on the conditions they grow, their odors can range from mild to creamy and pungent.
Figure 5. From "Cheese Microbes" by Button & Dutton, https://www.cell.com/current-biology/fulltext/S0960-9822%2812%2900659-8. Copyright 2012 by Elsevier Inc.
NEXT
sourdough bread
In addition to that, sourdough bread is another great example of the significance of microbial metabolism in the development of aroma. Sourdough fermentation involves a symbiotic relationship between yeast and lactic acid bacteria. Aside from that, sourdough is a naturally fermented mixture of water and flour. The microorganisms present in the dough metabolizes the sugars, which produces carbon dioxide and other organic acids such as lactic acid and acetic acid (Howell, n.d.). Moreover, the interaction between the enzymatic breakdown of proteins and microbial metabolism highlights the complexity of food food aroma. This also emphasizes how biological processes can impact the changes of chemical compounds responsible for smell, especially when microbial activity influences the formation of different types of volatile organic compounds that most likely contribute to sourdough's distinctive tangy and sour aroma.
microbial metabolism and its relation to sourdough
click here
you'VE unlocked your knowledge ABOUT
The microbial metabolism in food aroma
now that you've finished this level, You may proceed and click continue.
continue
MENU
level
Chemical Reactions
Start
Microbial Metabolism
End
CONCLUSION
In conclusion, food aroma is not a random phenomenon, but it is the result of comprehensive interactions between different chemical reactions and microbial metabolism. Additionally, both of these interactions add to the production of unique volatile organic compounds. Chemical reactions such as the Maillard reaction generate a huge number of aromatic molecules due to the enzymatic activity that accurs during the chemical process. Meanwhile, the microbial metabolism during fermentation contributes to additional compounds that enhance and expand these unique aromas. By understanding these mechanisms or processes, it becomes clear that food aroma is caused by different scientific methods, which is both shaped by chemistry and microbiology. Furthermore, this understanding also emphasizes the significance of volatile organic compounds and it how it serves as an important part of human perception because it allow humans to smell and experience food that many of them love and enjoy.
NEXT
REFERENCES
Drake, M., & McKillip, J. (2000). Fermentation Microbiology: Making Cheese, Yogurt & Buttermilk as a Lab Exercise. The American Biology Teacher, 62(1), 65–67. https://www.jstor.org/stable/4450828.
Fardis Malekijahan, Razavi, S. H., Melika Shafiepour, Afraei, M., & Nouri, M. (2025). Advances in microbial metabolism for flavor development: Exploring the roles of bacteria, yeasts, and molds in food applications. The Microbe, 9, 100623–100623. https://doi.org/10.1016/j.microb.2025.100623.
Flavor Chemistry Research at the USDA National Historic Chemical Landmark. (2013). American Chemical Society. https://www.acs.org/education/whatischemistry/landmarks/usda-flavor-chemistry.html.
Gholamipour-Shirazi, A., & Mossige, E. J. L. (2025). Mixing-driven flavor and aroma in fermented foods. Physics of Fluids, 37(3). https://doi.org/10.1063/5.0253287.
Howell, K. (n.d.). Microbial Flavor Profiles for Bread and Wine Production With Kate Howell. American Society for Microbiology. https://asm.org/podcasts/mtm/episodes/investigating-microbial-flavor-profiles-for-bread.
Jain, M. K., & Apitz-Castro, R. (1993). Garlic: A product of spilled ambrosia. Current Science, 65(2), 148–156. https://www.jstor.org/stable/24095056.
Kilic-Buyukkurt, O. (2024). Application of Molecular Sensory Analysis in Determining Food Flavor: A Review. Journal Raw Materials & Processed Foods, 5(1), 1–10. https://research.ebsco.com/c/mgfond/viewer/pdf/utbvmmxekn.
Krasner, S. W., McGuire, M. J., & Ferguson, V. B. (1985). Tastes and Odors: The Flavor Profile Method. Journal (American Water Works Association), 77(3), 34–39. https://www.jstor.org/stable/41273344?searchText=microbiology+of+food+aroma&seq=4.
Kumar Verma, D., Thyab Gddoa Al-Sahlany, S., Kareem Niamah, A., Thakur, M., Shah, N., Singh, S., Baranwal, D., Patel, A. R., Lara Utama, G., & Noe Aguilar, C. (2022). Recent trends in microbial flavour Compounds: A review on Chemistry, synthesis mechanism and their application in food. Saudi journal of biological sciences, 29(3), 1565–1576. https://pmc.ncbi.nlm.nih.gov/articles/PMC8913424/.
Kumar, P. (2023). The Science of Food Aroma: Understanding Its Role in Flavor and Quality. Agriculture Institute. https://agriculture.institute/food-fundamentals-cpo/science-of-food-aroma-flavor-quality/.
Scott, H. (2006). Better Dining through Chemistry. Gastronomica, 6(4), 74–77. https://www.jstor.org/stable/10.1525/gfc.2006.6.4.74.
The chemistry of flavor: The flavor researchers of USDA’s Western Regional Research Center. (n.d). U.S. Department of Agriculture. https://www.nal.usda.gov/collections/stories/chemistry-of-flavor.
What Is the Maillard Reaction? The Science of Flavor. (2025). Swiss Education Group. https://www.culinaryartsswitzerland.com/en/news/maillard-reaction/.
The Chemistry and Microbiology behind Food Aroma
Rochelle Macek
Created on April 18, 2026
Start designing with a free template
Discover more than 1500 professional designs like these:
View
Vibrant Breakout
View
Reboot Protocol
View
Science Breakout
View
Mystery Breakout
View
Musical Room Escape
View
Submarine Escape Game
View
Earth Day Escape Room
Explore all templates
Transcript
an escape game of "rochelle macek"
discover
The chemistry and micrbiology behind food aroma
Let's go!
MENU
level
Chemical Reactions
Microbial Metabolism
Start
End
Why does food smell the way it does?
Where does food aroma come from?
Click "I'M READY!" to learn and understand the role of chemistry and microbiology in creating food aroma.
I'm READY!
what is food aroma?
Food aroma plays a crucial role in how people perceive and experience food through smell. Although food aroma may seem like an ordinary sensory experience, it is most likely the result of complex chemical and micrbiological processes, These aromas are also produced through intrecate intricate interactions at microbial and molecular level. From the pungent odor of garlic, smell of freshly baked homemade bread, or the strong smell of cheese. Hence, understanding how chemical reactions and microbial metabolism make volatile organic compounds (VOCs) can show the significant role of chemistry and micrbiology in producing food aroma.
continue
Press any color to learn about the different process of chemical reactions of food aroma!
Chemical reaction in food aroma
Chemical reaction is one of the main contributors to food aroma since it occurs in any physical processes, such as cooking because heat is applied during this process.
Click here
volatile organic compounds
volatile organic compounds and its different types
Figure 1. From "Testing for Volatile Organic Compounds (VOCs) in Food" by Eurofins, https://www.eurofins.in/food-testing/blog/testing-for-volatile-organic-compounds-vocs-in-food/. Copyright 2016 by Eurofins Scientific.
Volatile organic compounds (VOCs) are chemical compounds that will evaporate in room temperature due to high pressure, which then reach the sensory receptors that help detect and perceive different aromas.
types of volatile organic compounds:
Next
Did you know?
SPEAKING OF SULFUR-CONTAINING COMPOUNDS!
Figure 2. From "Garlic bioactive substances and their therapeutic applications for improving human health: a comprehensive review " byFrontiers, https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2024.1277074/full. Copyright 2026 by Frontiers Media SA.
When garlic is crushed or minced, enzymes convert the sulfur-containing compounds into a precursor molecular substance. A precursor molecule is an odorless, non-protein amino acid stored in the cytoplasm of an inatct garlic cell. Hence, once garlic is crushed, it releases a strong odor because the non-protein amino acid of intact garlic cell becomes unstable. (Jain & Apitz-Castro, 1993). This process exhibits how chemical reactions can occur even without heat, which shows that it can also rely on enzymatic activity to create aromatic compounds. Additionally, these sulfur-based VOCs are highly potent, highlighting how even small molecular changes from a crushed or cut garlic can have a significant sensory impact. Together, these examples emphasize that chemical reactions are important in producing the compounds responsible for food aroma.
click here
maillard reaction
what is a Maillard reaction?
Figure 3. From "Food Processing: The Influence of the Maillard Reaction on Immunogenicity and Allergenicity of Food Proteins" by Wageningen University & Research,https://www.researchgate.net/publication/318917156_Food_Processing_The_Influence_of_the_Maillard_Reaction_on_Immunogenicity_and_Allergenicity_of_Food_Proteins?_tp=eyJjb250ZXh0Ijp7ImZpcnN0UGFnZSI6Il9kaXJlY3QiLCJwYWdlIjoiX2RpcmVjdCJ9fQ. Copyright 2017 by ResearchGate.
Maillard reaction occurs when reducing sugars interact with amino acids under heat, which is responsible for producing various kinds of compounds that allow the browning effect of cooked foods and creating rich aromas. These compounds also contain pyrazines, which produces the nutty and roasted aromas in many foods (Swiss Education Group, 2025). Aside from that, maillard reaction is a type of chemical reaction that demonstrates how chemical transformations in food can generate new molecules that evaporates in the air, which form volatile organic compounds that are detected by the human olfactory receptors (American Chemical Society, 2013). Therefore, as a result, foods like seared meat, baked bread, and coffee develop their own characteristic aroma.
click here
fun fact!
Scientific methods involving chemical reactions have been developed to analyze and classify the compounds of aroma. For instance, during the 1940s, Keene Dimick was one of the earliest flavor chemists at the Western Regional Research Center in USDA. He used an analytical technique through gas chromatography to find out what makes the strawberry smell the way it does. His goal was to learn what gave off its scent in order to improve processed foods in this era. Later during his research, he discovered that it was the strawberry essence that gives the scent of a strawberry. Methods were composed of evaporation, distillation, and extraction technologies. Later on, he published his research findings in 1956.
Figure 4. From "The Chemistry of Flavor: The Flavor Researchers of USDA's Western Regional Research Center " by U.S. Department of Agriculture, https://www.nal.usda.gov/collections/stories/chemistry-of-flavor. Copyright 2013 by National Agricultural Library of the U.S. Department of Agriculture.
done
you'VE unlocked your knowledge ABOUT
THE chemical reaction in food aroma
now that you've finished this level, You may proceed and click continue.
continue
MENU
level
Chemical Reactions
Start
Microbial Metabolism
End
Microbial metabolism...
Refers to the biochemical process that shows how microorganisms such as yeast, bacteria, and mold that breaks down nutrients to produce energy. According to a journal article from the National Library of Medicine, the author notes that during the process of microbial metabolism, microbes generate many byproducts, which are composed volatile organic compounds (VOCs) that contribute to aroma (Kumar Verma et al., 2022). Moreover, fermentation is a controlled application of microbial metabolism and is most likely used in many foods like baked goods and wine. These type of foods will eventually develop unique odors due to the specific metabolic actvities of microorganisms that are involved within the process.
What exactly is microbial metabolism?
click here
CHEESE PRODUCTION
microbial metabolism and its relation to cheese aroma
The changes in cheese is determined by the presence of lactic acid bacteria (LAB) during its fermentation process. These bacteria ferment milk into lactic acid, which causes the milk to coagulate or turn from its liquid form into a solid substance, turning it into whey and curds (Drake & McKilip, 2000). Furthermore, these bacteria also continue to produce enzymes that break down proteins and fats, transforming molecules into volatile organic compounds that create distinct aromas of several cheeses. The unique characteristics of different microbial species also contribute to the wide range of cheese aromas because based on the conditions they grow, their odors can range from mild to creamy and pungent.
Figure 5. From "Cheese Microbes" by Button & Dutton, https://www.cell.com/current-biology/fulltext/S0960-9822%2812%2900659-8. Copyright 2012 by Elsevier Inc.
NEXT
sourdough bread
In addition to that, sourdough bread is another great example of the significance of microbial metabolism in the development of aroma. Sourdough fermentation involves a symbiotic relationship between yeast and lactic acid bacteria. Aside from that, sourdough is a naturally fermented mixture of water and flour. The microorganisms present in the dough metabolizes the sugars, which produces carbon dioxide and other organic acids such as lactic acid and acetic acid (Howell, n.d.). Moreover, the interaction between the enzymatic breakdown of proteins and microbial metabolism highlights the complexity of food food aroma. This also emphasizes how biological processes can impact the changes of chemical compounds responsible for smell, especially when microbial activity influences the formation of different types of volatile organic compounds that most likely contribute to sourdough's distinctive tangy and sour aroma.
microbial metabolism and its relation to sourdough
click here
you'VE unlocked your knowledge ABOUT
The microbial metabolism in food aroma
now that you've finished this level, You may proceed and click continue.
continue
MENU
level
Chemical Reactions
Start
Microbial Metabolism
End
CONCLUSION
In conclusion, food aroma is not a random phenomenon, but it is the result of comprehensive interactions between different chemical reactions and microbial metabolism. Additionally, both of these interactions add to the production of unique volatile organic compounds. Chemical reactions such as the Maillard reaction generate a huge number of aromatic molecules due to the enzymatic activity that accurs during the chemical process. Meanwhile, the microbial metabolism during fermentation contributes to additional compounds that enhance and expand these unique aromas. By understanding these mechanisms or processes, it becomes clear that food aroma is caused by different scientific methods, which is both shaped by chemistry and microbiology. Furthermore, this understanding also emphasizes the significance of volatile organic compounds and it how it serves as an important part of human perception because it allow humans to smell and experience food that many of them love and enjoy.
NEXT
REFERENCES
Drake, M., & McKillip, J. (2000). Fermentation Microbiology: Making Cheese, Yogurt & Buttermilk as a Lab Exercise. The American Biology Teacher, 62(1), 65–67. https://www.jstor.org/stable/4450828. Fardis Malekijahan, Razavi, S. H., Melika Shafiepour, Afraei, M., & Nouri, M. (2025). Advances in microbial metabolism for flavor development: Exploring the roles of bacteria, yeasts, and molds in food applications. The Microbe, 9, 100623–100623. https://doi.org/10.1016/j.microb.2025.100623. Flavor Chemistry Research at the USDA National Historic Chemical Landmark. (2013). American Chemical Society. https://www.acs.org/education/whatischemistry/landmarks/usda-flavor-chemistry.html. Gholamipour-Shirazi, A., & Mossige, E. J. L. (2025). Mixing-driven flavor and aroma in fermented foods. Physics of Fluids, 37(3). https://doi.org/10.1063/5.0253287. Howell, K. (n.d.). Microbial Flavor Profiles for Bread and Wine Production With Kate Howell. American Society for Microbiology. https://asm.org/podcasts/mtm/episodes/investigating-microbial-flavor-profiles-for-bread. Jain, M. K., & Apitz-Castro, R. (1993). Garlic: A product of spilled ambrosia. Current Science, 65(2), 148–156. https://www.jstor.org/stable/24095056. Kilic-Buyukkurt, O. (2024). Application of Molecular Sensory Analysis in Determining Food Flavor: A Review. Journal Raw Materials & Processed Foods, 5(1), 1–10. https://research.ebsco.com/c/mgfond/viewer/pdf/utbvmmxekn. Krasner, S. W., McGuire, M. J., & Ferguson, V. B. (1985). Tastes and Odors: The Flavor Profile Method. Journal (American Water Works Association), 77(3), 34–39. https://www.jstor.org/stable/41273344?searchText=microbiology+of+food+aroma&seq=4. Kumar Verma, D., Thyab Gddoa Al-Sahlany, S., Kareem Niamah, A., Thakur, M., Shah, N., Singh, S., Baranwal, D., Patel, A. R., Lara Utama, G., & Noe Aguilar, C. (2022). Recent trends in microbial flavour Compounds: A review on Chemistry, synthesis mechanism and their application in food. Saudi journal of biological sciences, 29(3), 1565–1576. https://pmc.ncbi.nlm.nih.gov/articles/PMC8913424/. Kumar, P. (2023). The Science of Food Aroma: Understanding Its Role in Flavor and Quality. Agriculture Institute. https://agriculture.institute/food-fundamentals-cpo/science-of-food-aroma-flavor-quality/. Scott, H. (2006). Better Dining through Chemistry. Gastronomica, 6(4), 74–77. https://www.jstor.org/stable/10.1525/gfc.2006.6.4.74. The chemistry of flavor: The flavor researchers of USDA’s Western Regional Research Center. (n.d). U.S. Department of Agriculture. https://www.nal.usda.gov/collections/stories/chemistry-of-flavor. What Is the Maillard Reaction? The Science of Flavor. (2025). Swiss Education Group. https://www.culinaryartsswitzerland.com/en/news/maillard-reaction/.
CONTINUE
You MADE IT!
Thanks for playing! :)
Are you sure you want to leave?
You'll lose all your progress
BACK
exit