As promised, I will be writing today about the production of Worcestershire Sauce. I will give you a brief history, a description of the ingredients, and a summary of how some of them are made. I hope this is an enjoyable process for us all.
In his book on the sauce, Brian Keogh writes that Worcestershire sauce was first "synthesized" by two chemists, John Wheeley Lea and William Henry Perkins of Worcester, England. The Brits have a funny way of adding "shire" to the end of names. I'm not much for history, but I will note that Heinz (of ketchup fame) bought the rights to Worcestershire sauce in 2005 and now distributes it with the words, "The Original Lea & Perrins Worcestershire Sauce" on the bottle. I stumbled upon a bottle recently that must have been from before the Heinz takeover: it reads "The Original & Genuine Lea & Perkins."
Today a bottle of the sauce lists these ingredients: vinegar, molasses, high fructose corn syrup, anchovies, water, onions, salt, garlic, tamarind concentrate, cloves, natural flavorings, and chili pepper extract. The bottle that I referenced earlier lists mostly the same ingredients, but differs in containing hydrolyzed soy protein and eschalots and lacking cloves and chili pepper extract. It is pretty clear that Heinz is not selling "The Original Lea & Perkins," but it would be naive to expect anything different.
Vinegar is a good place to start, as it is the primary ingredient (other than water). Vinegar is a particularly interesting product from an engineering standpoint, as it requires three steps of biological growth during production, each of which must be carefully controlled to achieve the desired results. Typical malt vinegar is actually produced in a manner similar to the production of beer. Barley is first malted, which involves moistening the barley in large troughs and heating the environment. Moistening causes the barley (the seeds of the barley plant) to sprout, growing little shoots from the body of the grains. To provide energy for this process, enzymes in the grains break down stored starch into simple sugars such as maltose. The hope of life for the little barley grains does not last long, however; for all its efforts, the brewer will heat and kill the grains when they have broken down enough starch into sugar. The dry heat roasts the barley, and the degree of roasting determines many characteristics of the brew. As the sugars caramelize, more roasting generally corresponds to a darker beer, and a wide variety of flavors can be created in the roasting process alone.
Next comes the filtering process. Water is used to remove the new sugars from the barley, and filters retain the solids of the grains. The resulting solution contains sugars and proteins from the barley. The sugar water is then given to yeast, much like the yeast used to rise bread, and the microbes convert the sugar into ethanol, the common alcohol that makes my whiskey so wonderful. Humans and other multicellular organisms convert sugar into carbon dioxide that leaves the body through breathing. All of the carbon that is present in sugar reacts to form carbon dioxide. This is a very useful reaction for us, since carbon dioxide contains a lot less energy than sugar. Recall that energy is never created or destroyed, so the difference in chemical energy shows up elsewhere. Through the reactions of metabolism, body can convert the chemical energy in to all sorts of forms: most of it is turned into heat energy that warms the body or simply floats off; some of it goes to repairing and generating cells and tissue; and a little of it goes to mechanical energy like running, jumping, and playing. Yeast, it seems, is not quite as lucky. Instead of turning all of the carbon in sugar into carbon dioxide, some of it stays in the form of ethanol. Since ethanol has more chemical energy than carbon dioxide, less energy is available to yeast for every sugar molecule it can get a hold of. One advantage is that yeast does not require nearly as much oxygen as multicellular organisms, allowing it to live in a greater variety of environments.
Energy aside, yeast does turn sugar into ethanol and carbon dioxide. In the brewing of beer, this would be the end of the story. The beer would be bottled and shipped. However, in making vinegar, the ethanol is delivered to another set of organisms called acetogenic bacteria. Don't let the name fool you; acetogenic bacteria make acetic acid as a result of their form of metabolism, using the carbon from ethanol in this case. If yeast were unfortunate because of their way of making a living, these bacteria are even more so. Acetogenesis produces even less energy than fermentation, but fortunately the energy needs of bacteria are even less than those of yeast. Acetic acid gives vinegar its sour flavor, and the host of other compounds such as carmelized sugar produced in the brewing process give malt vinegar its other flavors.
I want to elucidate another very important ingredient of Worcestershire Sauce, one that finds its way into a multitude of other foods. Surely if you are fastidious and obsessive like me, you have noticed the "natural flavors" phrase tacked onto the end of a great many ingredient lists. My limited knowledge of the food and chemical industries has shown me how misleading this phrase can be. Any flavoring that comes from a biological source can be called a natural flavoring. This is in contrast to artificial flavorings that are synthesized through controlled reactions and use other chemicals as starting materials. I have actually had the opportunity on two occasions to synthesize the artificial banana flavoring found most obviously in banana Runts candy, and the second time I was able to walk out of the laboratory with a vial of the stuff for my friends to see (or rather smell). If the chemical synthesis of flavorings sounds unappealing, believe me that the methods of producing natural flavors are no better. In completely unnatural processes, solvents that are often dangerous or unhealthy are used to extract flavorings , and these must be removed properly for the "natural flavoring" to be fit for consumption. A prime analog is the removal of caffeine to produce decaf coffee. The solvent that is often used, dichloromethane, falls into the class of chemicals called halocarbons that gained so much notoriety for destroying the ozone layer. Furthermore, edible solvents can cause problems as well during extraction. If ethanol were used to remove flavors from fruits with seeds such as apples or peaches, it is very likely that cyanide, a potent poison, would be extracted along with the flavors. I certainly hope that food producers would have more sense than this, however. I hope I haven't scared you with any of this information, but I did want to dispel any illusion that natural flavors are somehow safer than their artificial counterparts.
So there you have it. I have told you a little about Worcestershire Sauce, and some of the steps that go into making it. I realize that I have left many steps and much subtlety out of the brewing process, but that discussion goes way beyond this note. Information about the other ingredients is easy to come by with a quick internet search, and I chose the ingredients I did because I feel I have an extended knowledge of them. Next week, tune in for an overview of the current scientific research in chemical engineering departments. I know you can't wait for that one!
Saturday, July 18, 2009
Saturday, July 11, 2009
What is a chemical engineer?
So the first post of the summer blog series on chemical engineering is appropriately about what a chemical engineer is. Crazy, I know.
It seems that there is a lot of confusion about what a chemical engineer actually does, judging by the questions that I am asked about what I study and what I could do with my degree. I can't say I'm surprised, since I didn't even know what chemical engineering was before I decided to be one! This may stem from the fact that chemical engineers are significantly different than the traditional types of engineers that long ago made bridges, fortresses, cannons, steam engines, and radios. These engineers have gone on to make skyscrapers, airplanes, car engines, and computers. Chemical engineers might be able to work on any of these applications, though we may not be the best at designing or maintaining any of them. We are most appropriately suited for work in the chemical industry, making products as diverse as shampoo, explosives, pharmaceuticals, and fuels.
Chemical engineers design the chemical plants that produce many of the compounds that are used today. There are many, many steps of heating, mixing, fermenting, pressurizing, filtering, and distilling that are required to make even the most basic products, and I hope to describe many of them in the coming weeks. Chemical engineers have knowledge of the physical, chemical, and thermal properties of a wide range of substances, and we use those properties to manipulate and create a desired product. To get the discussion started, I have made a list of characteristics of chemical engineers.
1. We don't actually use that much chemistry.
This comes as a shock to most people. "But you are a chemical engineer, aren't you?" Well, yes, but that probably doesn't mean the same thing to you that it means to me or to the chemical industry. Chemistry and chemicals generally conjure images of color-changing reactions in a beaker, seen through the foggy goggles provided by the school. The key difference between myself and a chemist is that, I don't make new chemicals. Chemists and pharmacists are responsible for making things like new plastics and cures for diseases, but chemical engineers are responsible for figuring out how to make lots of a new chemical. Almost always there are steps that are performed on a lab bench that could never be used on a large scale, and there are additional complications that arise when trying to mass produce a chemical. When I say that we have to figure out how to make lots of a chemical, I mean that we have to figure out how to make the chemical cheaply and without too much waste, all while using the resources that are available at the location of the plant. Often these goals are at odds with one another, in that doing better at one will cause problems with another. In my opinion, the core of any discipline of engineering is finding the solution that best satisfies conflicting goals.
We also don't do that much chemistry because for every reaction that occurs in a chemical plant, there are inevitably a dozen other large pieces of equipment used to make that reaction happen. Reactions almost always need to be heated or cooled, and often pressure has to drop or increase to achieve the proper reaction conditions. Reactions also always produce a mixture of products, and the desired products must be separated before they can be sold and used. In reality, all of these things occurred on your lab bench in general chemistry lab, but the auxiliary processes of heating, cooling, and separation were probably very expensive compared to the product you made; it just didn't matter at all, since you weren't trying to sell what you made. These concerns of cost, waste, and resources become central to the industrial chemical engineer.
2. Chemical engineers are very good at thermodynamics, heat transfer, fluids, and mass transfer.
I mentioned that I'm not very good at chemistry. This is true in that my skill in chemistry pales in comparison to a real chemist, though I am probably a lot better at chemistry than most people. I am really good at this strange science called thermodynamics, which describes how materials react to heating, cooling, and pressure and volume changes. It is very helpful in the chemical plant, where one must know, for example, how much heat it takes to make your chemical react or separate itself from the mixture it is in. Heat transfer, mass transfer, and fluids are three other areas of study that are fairly similar and help determine things like how long it will take for the heating to occur, or how much energy pump must use be to actually accomplish the
desired change in pressure.
3. We only know one equation.
In-Out+Generation=Accumulation
I'm beginning to realize that almost every chemical engineering equation I know is a special case of this equation. It says that if you put stuff into something, there will be more there, and if you take stuff out, there will be less stuff in there. Also, if somehow more stuff appears in your something, then there will be more stuff in there. I know I'm not explaining it very well, but I could write at least one note about this equation, and I probably will this summer. I'm also making the equation sound easier to use than it actually is: the terms "In" and "Out" often account for several different factors, and they are also often represented with complex mathematical expressions. "Generation" is even more tricky, as it is the term we use for chemical reactions and other confusing phenomena like nuclear reactions. "Accumulation" just makes your life a mess when it has to be included, as it is almost always represented as a differential in time that requires integration.
4. We're marginally good at biology.
In recent decades, there has been much interest within the scientific community in engineering using biological materials. The potential uses are diverse: using microbes and algae to produce fuel, the engineering of better synthetic joints, and the treatment of diseases using modified viruses. Chemical engineers have participated in many of these efforts because of the chemical basis of life. At the fundamental level of almost every biological phenomenon, there is a chemical reaction taking place. Chemical engineering departments (including the dept. at CSM) are beginning to integrate more biology in their curricula, and the chemical and biological engineering departments are combined at many schools (including the dept. at UW Madison). Again, my knowledge of biology is marginal compared to a real biologist or biochemist, but I know enough to apply the principles of biology to mass production of biochemicals. My senior design project was the design of a biofuel plant, for example.
Four is an awkward number, but I'm going to stop there because I've covered everything I wanted to. Next week, tune in for a description of how Worcestershire sauce is made!
It seems that there is a lot of confusion about what a chemical engineer actually does, judging by the questions that I am asked about what I study and what I could do with my degree. I can't say I'm surprised, since I didn't even know what chemical engineering was before I decided to be one! This may stem from the fact that chemical engineers are significantly different than the traditional types of engineers that long ago made bridges, fortresses, cannons, steam engines, and radios. These engineers have gone on to make skyscrapers, airplanes, car engines, and computers. Chemical engineers might be able to work on any of these applications, though we may not be the best at designing or maintaining any of them. We are most appropriately suited for work in the chemical industry, making products as diverse as shampoo, explosives, pharmaceuticals, and fuels.
Chemical engineers design the chemical plants that produce many of the compounds that are used today. There are many, many steps of heating, mixing, fermenting, pressurizing, filtering, and distilling that are required to make even the most basic products, and I hope to describe many of them in the coming weeks. Chemical engineers have knowledge of the physical, chemical, and thermal properties of a wide range of substances, and we use those properties to manipulate and create a desired product. To get the discussion started, I have made a list of characteristics of chemical engineers.
1. We don't actually use that much chemistry.
This comes as a shock to most people. "But you are a chemical engineer, aren't you?" Well, yes, but that probably doesn't mean the same thing to you that it means to me or to the chemical industry. Chemistry and chemicals generally conjure images of color-changing reactions in a beaker, seen through the foggy goggles provided by the school. The key difference between myself and a chemist is that, I don't make new chemicals. Chemists and pharmacists are responsible for making things like new plastics and cures for diseases, but chemical engineers are responsible for figuring out how to make lots of a new chemical. Almost always there are steps that are performed on a lab bench that could never be used on a large scale, and there are additional complications that arise when trying to mass produce a chemical. When I say that we have to figure out how to make lots of a chemical, I mean that we have to figure out how to make the chemical cheaply and without too much waste, all while using the resources that are available at the location of the plant. Often these goals are at odds with one another, in that doing better at one will cause problems with another. In my opinion, the core of any discipline of engineering is finding the solution that best satisfies conflicting goals.
We also don't do that much chemistry because for every reaction that occurs in a chemical plant, there are inevitably a dozen other large pieces of equipment used to make that reaction happen. Reactions almost always need to be heated or cooled, and often pressure has to drop or increase to achieve the proper reaction conditions. Reactions also always produce a mixture of products, and the desired products must be separated before they can be sold and used. In reality, all of these things occurred on your lab bench in general chemistry lab, but the auxiliary processes of heating, cooling, and separation were probably very expensive compared to the product you made; it just didn't matter at all, since you weren't trying to sell what you made. These concerns of cost, waste, and resources become central to the industrial chemical engineer.
2. Chemical engineers are very good at thermodynamics, heat transfer, fluids, and mass transfer.
I mentioned that I'm not very good at chemistry. This is true in that my skill in chemistry pales in comparison to a real chemist, though I am probably a lot better at chemistry than most people. I am really good at this strange science called thermodynamics, which describes how materials react to heating, cooling, and pressure and volume changes. It is very helpful in the chemical plant, where one must know, for example, how much heat it takes to make your chemical react or separate itself from the mixture it is in. Heat transfer, mass transfer, and fluids are three other areas of study that are fairly similar and help determine things like how long it will take for the heating to occur, or how much energy pump must use be to actually accomplish the
desired change in pressure.
3. We only know one equation.
In-Out+Generation=Accumulation
I'm beginning to realize that almost every chemical engineering equation I know is a special case of this equation. It says that if you put stuff into something, there will be more there, and if you take stuff out, there will be less stuff in there. Also, if somehow more stuff appears in your something, then there will be more stuff in there. I know I'm not explaining it very well, but I could write at least one note about this equation, and I probably will this summer. I'm also making the equation sound easier to use than it actually is: the terms "In" and "Out" often account for several different factors, and they are also often represented with complex mathematical expressions. "Generation" is even more tricky, as it is the term we use for chemical reactions and other confusing phenomena like nuclear reactions. "Accumulation" just makes your life a mess when it has to be included, as it is almost always represented as a differential in time that requires integration.
4. We're marginally good at biology.
In recent decades, there has been much interest within the scientific community in engineering using biological materials. The potential uses are diverse: using microbes and algae to produce fuel, the engineering of better synthetic joints, and the treatment of diseases using modified viruses. Chemical engineers have participated in many of these efforts because of the chemical basis of life. At the fundamental level of almost every biological phenomenon, there is a chemical reaction taking place. Chemical engineering departments (including the dept. at CSM) are beginning to integrate more biology in their curricula, and the chemical and biological engineering departments are combined at many schools (including the dept. at UW Madison). Again, my knowledge of biology is marginal compared to a real biologist or biochemist, but I know enough to apply the principles of biology to mass production of biochemicals. My senior design project was the design of a biofuel plant, for example.
Four is an awkward number, but I'm going to stop there because I've covered everything I wanted to. Next week, tune in for a description of how Worcestershire sauce is made!
Wednesday, July 1, 2009
Summer Blog Series!
[this note appeared on my facebook profile, but I thought I would post it here for the sake of having the suggestions for people to read]
So it's about time I start my summer blog series. In case you forgot or haven't been around me that long, I had a somewhat popular series last summer about science and technology. Most of these were related to chemical engineering, as that is my passion and area of expertise. This summer I would like to write more about the same topics. I haven't picked any specific subjects so far, and I would like any suggestions you might have. I would really like to answer questions like these:
How does ________ work?
How is (food/chemical/beverage/drug/object) made?
What are some of the important/interesting things you learned in your classes?
What does a chemical engineer actually do?
What are you/your friends doing for work now that you've graduated?
What sort of things are chemical engineers researching?
What are scientists and engineers doing for the world besides stimulating the economy with the buco bucks you make?
What makes you chemical engineers so awesome?
These are all, of course, suggestions. More specific questions would probably be easier to field. Chemical engineers are experts in strange things like energy, temperature, pressure, heat, chemical reactions, biology, food and "beverage" production, biofuels, electronics manufacturing, and applied mathematics. Questions about any of these would be great too.
Finally, I will be starting a blog off facebook! The notes will still be imported here, but it would be way awesomer to go to that site. I shall call it The Elegant Design. I hope to hear from you soon!
I will also be restarting my list of facebook subscriptions with the beginning of this new series and blog, so leave a comment if you've read this far and I will put you on the list!
So it's about time I start my summer blog series. In case you forgot or haven't been around me that long, I had a somewhat popular series last summer about science and technology. Most of these were related to chemical engineering, as that is my passion and area of expertise. This summer I would like to write more about the same topics. I haven't picked any specific subjects so far, and I would like any suggestions you might have. I would really like to answer questions like these:
How does ________ work?
How is (food/chemical/beverage/dr
What are some of the important/interesting things you learned in your classes?
What does a chemical engineer actually do?
What are you/your friends doing for work now that you've graduated?
What sort of things are chemical engineers researching?
What are scientists and engineers doing for the world besides stimulating the economy with the buco bucks you make?
What makes you chemical engineers so awesome?
These are all, of course, suggestions. More specific questions would probably be easier to field. Chemical engineers are experts in strange things like energy, temperature, pressure, heat, chemical reactions, biology, food and "beverage" production, biofuels, electronics manufacturing, and applied mathematics. Questions about any of these would be great too.
Finally, I will be starting a blog off facebook! The notes will still be imported here, but it would be way awesomer to go to that site. I shall call it The Elegant Design. I hope to hear from you soon!
I will also be restarting my list of facebook subscriptions with the beginning of this new series and blog, so leave a comment if you've read this far and I will put you on the list!
only the beginning
Yay google: making social interaction without physical proximity easier every day. I'm starting a blog here that I would like to keep for the duration of my time in graduate school. We'll see if it survives that long. My last one on xanga didn't make it more than a couple years. Just to get us started, a few fun facts about me:
- I've lived in Colorado for my whole life, but I won't be able to say that for much longer.
- I like Jesus. A lot. Knowing him and following his teachings has changed my life.
- I'm pursuing my PhD in chemical engineering at the University of Wisconsin at Madison.
- I get excited about equations and solutions. I especially like the elegant ones.
- My ears were pierced for a while, but I took them out and the holes healed, sort of.
- I have a wicked watch tan and a worse farmer's tan.
- I used to run track, but I quit because it wasn't the best use of my time. I ride bikes now.
- I was the chapter vice president of Tau Beta Pi, the engineering honor society, for a year.
- I hate the cold, which is ironic considering my choice of graduate school.
- I want to be a professor someday, because I like teaching and working with people.
- I don't watch TV. I think it's a colossal waste of time.
- I really like music, especially music that is artistic and demands skill.
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