To organic or not to organic, that is the question?

To organic or not to organic: that is the question?

In recent years the American diet has gone through a lot of changes—changes caused by fads. For instance, do you remember when carbohydrates were the enemy and no one wanted anything to do with them? It was the Atkins (no carb) diet fad, and was supposed to help you lose weight and get that Baywatch beach body. But then we learned that carbs are actually our friends and humans need them as a means of getting energy. Oh, but what about fats? Remember back then when people hated fats just as much as they (now) hate Justin Bieber? Or Kim Kardashian? Yeah, that no-fats diet fad!—Well, it turned out that humans need good fats and totally eliminating them from our diet is not ideal. (Lowering saturated and trans fats has been correlated to lowering the chances of getting certain diseases…but that’s a complicated subject.) Today the food fads continue, and one of the predominant diets is…organic food. It seems that in today’s society people are under a strong impression that organic food is by far way better than conventionally grown food; but is this truth or another misconception that would change if the public were more informed?

We walked into class to see a bunch of different delicious foods—like Noah’s ark, two by two, one organic and the other conventional. But there was a problem…we were not told which was which, we had to guess. From looking at the picture below can you figure out which foods are organic and which are not?

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How do you think that went? In you can’t see clearly, under each food is either an A or B. Aren’t they cute?

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I know what you’re thinking, “Which is which…Do the organic foods look better than the conventional foods? Or is it the other way around?” Well, before I reveal the answer…. Let’s take a look at 3 common misconceptions of organic food and make a more informed decision on whether “to organic or not to organic”.

Misconception 1: Organic Food is grown the way nature intended.

The term organic is not as clear as one would think. The USDA has its own way of defining what organic is, as summarized here:

  • Preserve natural resources and biodiversity
  • Support animal health and welfare
  • Provide access to the outdoors so that animals can exercise their natural behaviors
  • Only use approved materials
  • Do not use genetically modified ingredients
  • Receive annual onsite inspections
  • Separate organic food from non-organic food

This information can be found on the following URL: http://www.usda.gov/wps/portal/usda/usdahome?contentidonly=true&contentid=organic-agriculture.html

The list seems great, it promotes animals getting exercise (something we should do, too!) and that no genetically modified material be used. But there are some ambiguities, such as that animals are “provided access” to the outdoors and that only “approved” materials can be used. When digging a little further, the word access should be taken literally, because animals that are grown organically have access to the outdoors…but they do not necessarily live a lifestyle that can be considered “free-range”. Organically grown animals can be subject to conditions similar to those faced by conventionally grown animals, as detailed in Michael Pollan’s Omnivore’s Dilemma (p. 171). The only difference is a door to the outdoors that they can access for some allotted amount time before they are slaughtered (p. 172).1

The phrase “only use approved material” also has some ambiguity to it, as well. For instance, pesticides can be used on organically grown food as long as they are “natural” or, in other terms, not made “synthetically” in a lab. But the chemicals could be identical to those used on conventional farms. Although the amount of pesticides that organic food receives is limited, organic farming can have other adverse effects, which leads to our second…

Misconception #2: The process by which organic food is grown is good for the environment.

Some people decide to buy organic because they think it is more ecologically friendly. But there have been studies that show that this is not entirely true. For instance, the studies cited here2 found that some organic pesticides have been shown to be equally or less effective at pest control. They also have a higher Environmental Impact Quotient, which tests the environmental impacts of pesticides (higher numbers are associated with more negative impact, while 0 is a neutral impact).

Misconception #3: Organic foods are more nutritious than conventionally grown food.

A great number of people want organic food to be nutritionally better than conventionally grown food. It would make sense because organically grown foods are grown under more restricted guidelines that should promote healthier food. Whole Foods even posted on their website that studies have found that fruits grown organically have more phytochemicals (chemicals that have been linked to better health) than non-organic foods.3 But scientific studies show (and popular nutritionists sometimes agree) that there are no scientifically proven studies that demonstrate significant statistical differences between organic and conventional foods in terms of their nutritional value—see Marion Nestle’s What to Eat, p. 53. Some even say that “any consumers who buy organic food because they believe that it contains more healthful nutrients than conventional food are wasting their money.”4,5

We would be misleading you if we didn’t mention that conventionally grown foods do use pesticides, are not regulated in that regard, and can be extremely environmentally unfriendly as well.

So, now that we are more informed: Should we organic or should we not organic? Organically grown foods do have pesticides—alright, fine. But they are also subject to stricter guidelines so there are likely fewer pesticides in organic food than in conventional food. Organic foods are perhaps not as environmentally friendly as they are advertised to be, but that doesn’t mean conventionally grown food is any better (it’s probably not), especially when taking into account the larger scale on which conventional food is grown. Organic food has not been proven to be more nutritious, but there is some evidence that shows that organic fruits have more phytochemicals than conventional fruits. So what is the verdict, should we organic or should we not organic?

Now that you’re more informed about organic and inorganic foods, try guessing again, like we did.

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Okay, this is the time for the results. If I were a betting individual I would bet you probably did way better the second time around. This shows how important it is to be informed about what organic and conventional actually are.

Foods Organic = plate A Conventional = plate A
Apples X
Blueberries X
Red peppers X
Yogurt X
Chocolate chips X
Applesauce X
Tomatoes X
Animal Crackers X
Pita bread X
Raspberry X
Peanut butter X
Cheddar cheese X

So what’s the verdict, should we organic or should we not organic?

Verdict:

It’s up to you.

(You really thought I was going to decide for you?)

Reference

1: Pollan, Michael. The Omnivore’s Dilemma, Penguin Random House Audio Publishing Group (2006), pp. 171 – 172.

2: Bahlai CA, Xue Y, McCreary CM, Schaafsma AW, Hallett RH (2010) Choosing Organic Pesticides over Synthetic Pesticides May Not Effectively Mitigate Environmental Risk in Soybeans. PLoS ONE 5(6): e11250. doi:10.1371/journal.pone.0011250

3: (http://www.wholefoodsmarket.com/blog/5-myths-about-organics) (date accessed: May 5, 2015)

4: Nestle, Marion. What to Eat, North Point Press/ Farrar, Straus & Giroux (2006), pp. 53.

5: Joseph D. Rosen. A Review of the Nutrition Claims Made by Proponents of Organic Food Science and Safety (2010). 9(3). pp.270-277.

Public Information Campaign

On April 28th, the class was able to showcase our cumulative food chemistry knowledge at a public information campaign. This consisted of four different group presentations, each debunking a food myth or common misconception. The campaign targeted all audiences, ranging from high school or college students with no knowledge of science, up to science professionals. No matter the academic background of the attendee, everyone left the Geneva room as a well-informed consumer!

Great turn out!

Great turn out!

Reading the Labels – Vernon, Adonis and Zhou

The first group chose to focus their presentation on unwrapping the confusing jargon within a list of ingredients. They covered the main categories of ingredients that you typically find in packed foods, such as sugars, fats, flavors, preservatives and corn. This group also showed how a label is organized from highest content to lowest, showing that corn and sugar are often the most abundant in packaged foods. They also demonstrated the different ways a label will try to disguise its ingredients, such as listing sugar under several different names that a typical consumer may not recognize.

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All About That Fat – Kelly, Dominique and Anola

The second group’s presentation aimed to inform the audience on the different types of fats that we eat. This group’s goal was to leave the viewer with enough knowledge to make their own informed decision on whether certain types of fats are good or bad. The presentation began with a description of the difference between saturated and unsaturated fats, in terms of both chemistry and physical state. The group then went on to discuss how cholesterol levels relate to fat intake, and the differences between LDL and HDL cholesterol. This presentation also touched on other aspects of fats such as cis and trans fats, and omega-3 fats.

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Can I Still Eat That? – Carly, Josh, Amelia, Adam

The next group focused on uncovering the truth behind expiration date labeling and the (bio)chemistry of what happens during food spoilage. This group presented the history behind expiration dates, pointing out that they are not actually required by law on any packaged foods other than baby food, but are rather a choice made by companies. The presentation also went on to show what causes spoilage, such as bacterial growth and mold, and methods of preventing that spoilage, such as pasteurization and irradiation. The group concluded by pointing out that foods can often be enjoyed beyond the labeled expiration date–but that consumers should use just use their (well-informed!) judgment.

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GMOs – Adrian, Grace, Erin

The final presentation of the campaign aimed to inform the audience on the truth behind the much debated topic of genetically modified organisms. This group gave a brief background on the science behind GMO, examples of the most widely used GMO crops and talked about how they have actually been beneficial to our food system. The presentation was a good way to show the consumer that GMOs are not as bad as they are made out to be.

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Food Safety

The question of food safety is an interesting one in that most people believe it is an absolute need. Very few people are going to advocate for a measured response to contamination. 19 million pounds of fresh and frozen beef, 400,000 pounds of frozen, fully cooked chicken or 25,000 pounds of pork rinds is a lot of food–and contamination has occurred affecting each of these. Clearly, the government and companies are prepared to recall food in the event of a contamination.

What is the best way to regulate food markets for safety and preventing contamination? Some will advocate for a government with regulation and imposed standards to penalize offending businesses, and others will advocate for market freedom with sellers that are unsafe selected against by market forces. At this point, the question is overtly political based on preconceived notions. However, there are some general trends under this framework of food safety.

The question of safety is redefined as a question of conventional versus organic by some. Some advocate that specific practices of organic farmers are better at creating safer meat, for example. Practices critiqued are the crowded conditions, treatment with antibiotics, and slaughter in hot and dirty factory conditions. But if some are able to implement these “safer” practices while conventional meat is still available, then we will effectively create a two-tier system in which the rich can afford ‘organic’ and ‘safe’ while everyone else eats ‘conventional’ and ‘unsafe’ meat. If the whole system is replaced with organic, then we could effectively price out some segment of the population from having fair access to meat. That is not to say that organic advocates intentionally for some terrible, class-ist ideal; some of the ideas are good. Grass feeding does have many positive benefits to both the animal and the consumer: rates of harmful bacteria (like Campylobacter and E. coli O157:H7) in cows tend to be lower, and many believe that the flavor is better. More room for movement of animals tends to cause better muscle definition and animal quality of life. How do we want to reach the best possible end for food safety? Should society innovate and create industrial solutions, or should society question modern practices and return to previously effective methods?  (And how effective were those methods?)

How do GMOs fit into this discussion?  Are they safe?  Are GMOs any different from non-GMO food?  While many would like for there to be obvious differences between GMOs and non-GMO food, there is frequently no noticeable consumer difference.

What about another modern method for food safety, irradiated food, which is facing critiques? The process of irradiating food works by using high-energy electromagnetic radiation to disrupt standard DNA function. This causes bacterial and microorganism death while preserving the quality of the food going through the process. A common question is, “If it causes bacterial and microorganism death, why is the food safe to eat afterwards?” The answer is that exposing something to radiation does not make it radioactive. Food from the microwave (electromagnetic radiation!) is not radioactive, just as you are not radioactive after sun tanning, even though this also involves electromagnetic radiation. The bacteria and microorganisms that are now dead and on the food are safe to consume. The body already has all needed digestive enzymes to consume most foreign matter. The food that we eat that is not irradiated has both living and dead bacteria and microorganisms all over it. Food to be cooked in an oven, grilled, fried, etc. is covered in bacteria and microorganisms (at least, when it’s raw), but the vast majority do not affect us. Additionally, bacteria and other microorganisms cannot become resistant to irradiation as they can to an antibiotic. Some challenge that we should make the process so clean as to not even need irradiation, but that is perhaps beside the point:  the process of irradiation provides no additional negative consequences.

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With the question of food safety and safety in general, many people feel that they are the best arbiter for their own safety. As such, above is a guide to identifying different codes at grocery stores. Below is the label used to identify irritated foods. The best way to keep yourself and your family healthy is to be an informed consumer. This means understanding the science behind the production of the food you consumer and methods we use to keep our food safe for consumption.

How to cook a vegetable?

How to cook a vegetable? Or how to cook food to make food taste better? That is a problem that has been studied for a long time. In 1988, a brand-new cooking method was proposed by two scientists: the scientific discipline called “molecular gastronomy.” The purpose of this new cooking method is to give people the ability not only to taste food, but also to experience food in ways other than simply flavor.

Honeydew is a common fruit. But can you imagine “drinking” a honeydew bubble? In this week’s food class, we used some “magic chemistry” to make honeydew bubbles! First, the honeydew juice was separated from the melon. Second, 1 gram of sodium alginate was added to the honeydew juice. But wait a minute, what is sodium alginate? It’s a polysaccharide (string of sugars) found in the cell walls of certain algae (alginate, right?), which looks like the structure here, except that the carboxylic acids (O=C-OH) are sodium salts:Alginsäure.svg

After adding sodium alginate, the honeydew juice, which had been crystal clear (but green), became thick, as seen in the picture:

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In the third step, 39 g of CaCl2 was dissolved in 655 g of water. What came next was the most important “magic” part of making honeydew bubbles:  the honeydew mixture was slowly added to the CaCl2 solution to form the bubbles.

When the honeydew juice/sodium alginate mixture was added to the CaCl2 solution, a layer of gel formed outside of each honeydew drop.  This gel was made of water trapped by calcium alginate, which is much less soluble than sodium alginate. That layer of precipitate made the shape of each bubble and locked the rest of the honeydew juice inside of the bubble. So the outside layer was the gel and inside was still liquid. That property can make infinite possibilities. We can make small bubbles like this:IMG_5380

or worms like this:

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or blobs like this (oops, poured it in too quickly):

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So by using chemical reagents, we can make honeydew juice into any shape we want. In other words, food chemistry gives cooking infinite possibilities.

The Corn People

The class started off with Professor Miller entering with bags of junk food, dumping it on the table, and asking the class, “What food on the table would you eat?” Some responded with, “everything!”

Junk food discussed about in class

We took a closer look at the food on the table and the class set out to divide the food products into two different groups; things I would eat and things I would not eat. The labels on the different packages of food were dissected to determine which category they would fall under. Some of the main ingredients found in junk food were lecithin, which is an emulsifier to keep things together, shown below.

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Other ingredients include sugar acting as a sweetener, citric acid acting as a preservative, caramel color for coloring, monosodium glutamate (MSG) for enhanced flavor, niacin for nutrients, oil, and xanthan gum acting as a thickener. We also discussed the different structures of antioxidants such as Butylated hydroxyanisole (BHA), below on the top, and Butylated hydroxytoluene (BHT), below on the bottom.

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We did not read all the labels on every food product on the table but the ones that were read were put in the things I would eat category; english muffins, tortilla, pita bread, popcorn, yogurt, protein drink, and potato chips.

A saturated fat is a solid at room temperature
which is able to stack while an unsaturated fat is liquid at room temperature and is not able to stack. Palm oil is present in popcorn which is a saturated fat that gives popcorn its qualities.

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When reading the nutrition label of many foods, sugar came up numerous times in many different forms. Some different types of sugar are disguised as sucrose, maltose, dextrose, fructose, glucose, galactose, lactose, high fructose corn syrup, and glucose solids. If all the different types of sugars were combined into one ingredient, then the first ingredient the consumer would come across when reading the nutrition label would be sugar. Most consumers would not buy something with sugar as the number one ingredient, so companies disguise the ingredient by giving it different names used on the nutrition label. Alternatives to sugar available are artificial sweeteners such as Splenda (top), which is sucralose, NutraSweet (middle), which is aspartame, and Sweet’N Low (bottom), which is saccharin.

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There is a lot of hype about high fructose corn syrup and how it is bad for a person’s health, but sugar is just as bad as high fructose corn syrup and there is no health benefit for using sucrose over high fructose corn syrup.

A question about genetically modified organisms (GMO’s) came up in our discussion about ingredients. The bigger question of “What is modification?” was asked. Most things we come in contact with in our everyday life are modified, so should everything be labeled as modified then? Even the Native Americans were using modified corn because the crop had been selected for particular genes. Is it modification or selection?

Our discussion turned next to corn. The anatomy of the corn is shown below.

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The main parts of corn are the germ where the oil is, the endosperm, and the kernel. The yellow color of the kernel is due to zeaxanthin, whose structure is shown below.

Zeaxanthin

The other part of the corn is the cob. Some fates of the cob are feed for animals, furfural which is an organic compound used in renewable chemical feedstock, and ethanol for biofuel. There are many resources used to grow corn such as tractors, nitrogen, fertilizers, and acid rain. Fertilizers are very important in the growing process and can mainly be found in the form of ammonium nitrate. The Haber process is how nitrogen is fixed and how the fertilizer is made in modern times. The combination of nitrogen and hydrogen along with heat and pressure gives ammonia used to make the fertilizer.

The discussion of being in favor of continuing or ceasing government corn subsides was embarked upon next. Everyone came up with a reason for either side of the argument. Some of the ideas brought up that were in favor of continuing the government corn subsides are that it helps farmers financially and if it were ceased it would bankrupt farmers, overproducing corn does not mean obesity, and produces biofuels. There were many more arguments in favor of ceasing the government corn subsides such as it makes food bad for people’s health, hurts farmers because they are dependent on the government, does not allow for fair trade, is not sustainable economically, supports animal cruelty by being able to put animals in small spaces and give them feed from corn to eat, creates food deserts, results in a loss of biodiversity, and results in being dependent on foreign markets for other crops.

There were many different topics discussed in class that ultimately helped us answer two questions for ourselves: (1) What could you make at home—and what would the difference be? And, (2) What is food (and what isn’t food)?”

A Quick Guide to Eggcellent Emulsions

Mayonnaise is America’s favorite condiment, bringing in a total of $401,204,800 in sales annually (see link). There is something about this gooey, spreadable and very versatile condiment that people find irresistible. However, I have never liked mayonnaise and as a kid the mystery of what mayo actually was and what held it all together prevented me from allowing it a place on my sandwich. This post serves as a guide to three popular emulsions: mayonnaise, Hollandaise, and sauce mornay.

What is an emulsion?

An emulsion is a mixture of two incompatible liquids, with droplets of one liquid dispersed in a continuous phase of the other (McGee, p595). Milk, cream, and egg yolks are all examples of natural emulsions although most are commonly used as sauces. The two categories of emulsions are oil-in-water and water-in-oil, distinguished by which is the continuous phase.

Why use egg yolks?

In addition to two incompatible liquids, stable emulsions include a third ingredient, the emulsifier. You may notice that many sauce recipes include egg yolks. This is because egg yolks contain the emulsifier lecithin. Emulsifiers have an oil-like (hydrophobic) end and a water-soluble (hydrophilic end). The sauce is created when the oil droplets are broken up very small and surrounded by an emulsifier. Proteins and other bigger molecules also act as emulsifiers by getting in the way and breaking up smaller molecules, such as oil droplets.

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Diagram of the general properties of an emulsifier.

What makes emulsions challenging?

The fact that emulsions contain two substances that don’t want to go together on their own makes them particularly challenging, it is not a spontaneous process. Energy, in the form of mixing, must be added in order to overcome surface tension. If this force is not overcome, or the emulsion separates again, it is “broken”. However, even if the two phases have coalesced, it is possible to recreate the emulsion by adding more emulsifier and continuing to vigorously mix to break apart the oil droplets.

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Picture of “broken” mayo (left) and Hollandaise (right).

MayonnaiseThe mayonnaise was created five different ways, incorporating three different mixing techniques and two different types of oil. The three different mixing techniques were using a food processor, by hand and with a salad dressing vessel. The difference was noticeable in the final products. The mayo that was only shaken as if it were a salad dressing did not create a proper emulsion and the food processor was able to. In addition the mayo whisked by hand took a lot of effort to create the emulsion. In order to create a successful emulsion, the oil droplets must be broken up very small and if they are not then the surface tension will not be overcome.

Mixing methods

One mayo trial was whisked by hand (left) while three used the food processor (right).

The other change made was substitution extra-virgin olive oil. Extra-virgin olive oil is less acidic and more viscous than regular oil and therefore was able to be broken down into smaller oil droplets. The color was also an indicator of how well the oil droplets were broken down, because bigger droplets reflect light more.

Hollandaise

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(1) Butter used as fat source, (2) homemade butter used as fat source, (3) clarified butter used as fat source, (4) margarine. The fifth trial was the “broken & fixed” sauce (seen in photo below).

The Hollandaise sauce was also created five different times, using four different fat sources. The different fats (butter, homemade butter, clarified butter, and margarine) changed the recipe by having different concentrations of fat. Regular butter includes milk fats, proteins, and lactose while clarified butter is only milk fat and homemade butter has more buttermilk and water. Therefore the clarified butter thickens the emulsion as it is added while the regular butter than clarified butter thinned the emulsion. The thickness of the clarified butter made it harder to break into small pieces and create the emulsion, resulting in a broken mixture. The margarine acted similar to the other butters.

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The light roux, (2) medium roux, and (3) dark roux.

Sauce Mornay was created three times, varying the cook time and the color of the roux each time. This sauce is different than mayonnaise or hollandaise because it is not created using the lecithin from egg yolks as an emulsifier. Instead, it incorporates milk and cheese. The cooking time changed the flavor of the sauce because of the Millard reactions that occur and change the flavors. They also account for the changing of the color.

DSC_0572-1024x685In conclusion, America’s favorite condiment is actually a complex and delicate balance of oil and water forced by an emulsifier and blender to cooperate and join together as one spreadable substance.

All About That Base-Edible Science Fair!

Our week started off rather excitingly with our Edible Science Fair, in which the class split into 4 groups and each presented on a topic of their choice, having to do with the chemistry of food, of course! The four groups that had stations at the fair presented on Enzymes, Emulsions, Fermentation and Coagulation. Each group was responsible for having visuals to help participants learn about their respective chemical properties and also each group had food dishes that adequately displayed their chemical property in food.

To start off, Team Enzyme had many different food dishes that were used to explain how much of a role enzymes play in our food. First, they made two batches of the same recipe of beef stew, with one difference, one batch had meat that had been tenderized and the other batch had meat that was not tenderized. Meat tenderizer can be bought at any local grocery store and the active ingredient in meat tenderizers is an enzyme called bromelain. In practice, the tenderizer should make the meat much easier to chew, the meat should “melt in your mouth”. These two dishes proved to illustrate this property very well as one could definitely taste a difference in the meats of the two respective stews. Team Enzyme also had various types of Gouda cheese that could be sampled to illustrate the effects of the enzyme renin on the protein casein. Renin is the enzyme in cheese that breaks down casein, which is the primary protein structure in cheese. This breakdown of proteins into amino acids allows for flavor development in more ripe cheeses. The group had out three different types of aged Gouda to illustrate the flavor and structural changes over time. Finally, the enzyme group displayed different types of food that undergo browning due to oxidation from the air. Polyphenol oxidase is the enzyme that is responsible for this oxidation. This phenomenon can be seen in apples and avocados when they are left out in the open for extended periods of time. To illustrate this phenomenon, the group cut apples at various times before the event and let them sit out to show the effects that browning had on the fruits.

Team Enzyme showcasing their cheese, stew and fruit!

Team Enzyme showcasing their cheese, stew and fruit!

Next comes Team Emulsions, who demonstrated their property through homemade whipped cream and salad dressing. An emulsion is a mixture in which oil is dispersed in water, something that should not normally happen. This can happen because of the properties of an emulsifying agent, such as lecithin, that has a two different ends. One end is hydrophobic and attaches to water and the other end attaches to the oil. Salad dressing is a classic example of an emulsion as it is fat that is suspended in water. Whipped cream is an example of an emulsion in which air is suspended in liquid, and the fat in the cream acts as the emulsifying agent.

Team Emulsions with one if their emulsions!

Team Emulsions with one if their emulsions!

Third was Team Fermentation and they demonstrated the property of fermentation using apple juice and yeast. Fermentation is a process in which sugar is converted to gas or alcohol. The classic example of fermentation is its use in the process of making beer and other alcoholic beverages. To demonstrate their topic, this group fermented apple juice, in turn making it an alcoholic cider. The group added yeast and sugar to a gallon of apple juice and allowed it sit uncovered in a dark room for a few days. They also had a gallon of regular apple juice so that participants could taste the difference between the two. Finally, to demonstrate the byproducts of fermentation the group added yeast, sugar and water to a few beakers and placed balloons on the openings of the beakers. Because CO2 is a byproduct of fermentation, the balloons started to full with air as the process went along.

Team Fermentation with their fermented apple juice and their balloon experiment!

Team Fermentation with their fermented apple juice and their balloon experiment!

Vernon, Adonis, and Zhou presented a terrifically engaging and informative presentation about coagulation in foods. They exhibited the different modes of coagulation, for example via pH changes in the formation of cottage cheese, enzymes in the formation of regular cheese, and salt in the formation of tofu. They used photos, such as the one below, in a slideshow to inform fair-goers of the implementation of coagulation in the production of cheese and other products. Zhou made a delicious traditional Chinese tofu dish with plenty of samples available so that people could taste the product of coagulation! The team members would then explain the coagulation of the conglycinin protein in soybeans by magnesium ions in magnesium sulfate in the production of tofu. The magnesium ions bind to the negatively charged parts of the protein, causing them to coagulate. The team also made eggs and showcased their coagulation process.

Team coagulation with their eggs and tofu!

Team coagulation with their eggs and tofu!

All in all, it was a very successful event and we felt that we helped people to understand some chemical aspects of the foods that they see on a regular basis. We also learned a lot in the process!

Ag Station:

During class this week, we had the wonderful opportunity of visiting Cornell’s New York State Agricultural Experiment Station (NYSAES). For those of us that are interested in possibly pursuing a career in food science, this was like a fairytale; even better than Disneyland for a child. While, they were in the process of moving to the Cornell facility, the Food Science department at NYSAES was eye-opening. We learned real-world applications of chemistry, including physical chemistry, in the food industry. For example, the contraption pictured below is used for distilling, and is made of copper because copper helps remove sulfides from the distillate product.

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Pictured is a device made of copper that is used in the distillation process.

One of the most intriguing parts of the visit was the lab. Dr. Gavin Sacks led us on a tour of the facility, and then finally to the highly anticipated olfactometer. The olfactometer is a specialized machine that is built to receive a vial of fluid and then transmits the various odorous compounds of the substance out of a tube that is placed at the edge of a participant’s nose. I had the blessed opportunity of experiencing the olfactometer containing a vial of freshly brewed coffee. Below is the setup of the olfactometer. Once the coffee sample was placed in the appropriate receptacle, the coffee option was selected in the software on the computer. A list of smells then came up on the screen. After waiting a few minutes for the compounds to be recognized by the machine, I started to smell things. The software ran a background timer, and various smells were expected to appear at different times, based on the fact that the sample was coffee.

One of the scientists at the lab, Ed Lavin, explaining how the olfactometer works, and how to make a sample for it.

One of the scientists at the lab, Ed Lavin, explaining how the olfactometer works, and how to make a sample for it.

The experience was incredible. Olfaction is a sense we usually take for granted, and most people do not understand how many different compounds are involved in different smells. There are thousands of compounds that make up the smell of freshly roasted coffee, but intriguingly the lab has found that every different smell can be recreated using only a few hundred chemical compounds; for example, it only takes about 24 to make a very good approximation of bourbon. When I sat at the olfactometer, I got to experience the isolated compounds that contribute to the delicious aroma of a fresh cup of coffee. However, not all of these compounds smelled as delicious as coffee. For example, one of the smells to be identified was the smell of dirty socks. This aroma came up quite a few times, and is a characteristic smell of short chain carboxylic acids. Our experience at the NYSAES showed us just how much thought and effort is involved in the production of food, and the complexity of the makeup of food.

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Experiencing the Olfactometer!