Got Milk?

The dairy industry today is one of the largest industries in the world.  The milk industry produces $21 billion a year.  Milk can then be transformed into a variety of different products that range from ice-cream to cottage cheese and everything in between.  Milk is also made up of mostly water.  However, there is also fat, proteins, lactose and other minerals floating around as well.  Both the readings and the class discussion touched upon the two proteins that make up milk, casein and whey.

Nowadays, many cows are constantly pumped with different antibiotics for various reasons.  The most common is rbST or recombinant bovine somatropin.  Some people see this as controversial, thus the FDA conducted a study and concluded that there is no difference in milk from rbST treated cows vs. non-treated cows.  Now, who am I to say which one is healthier or tastes better?  That is up for your interpretation!

It is important to note the two types of ways that the FDA ensures that the milk is safe for the public.  The first is pasteurization.  Simply put, it is heating the milk until all the dangerous alive stuff is now dead and not dangerous.  Adding a little bit more complexity entails the preservation of milk by killing pathogenic microbes by inactivating certain milk enzymes.  The second major way is through homogenization.  This is just the funneling of milk through smaller nozzles to break apart the fat globules that are in the milk.  This aides the process of keeping the milk the proper consistency.  Simply put, it makes sure the fat within the milk is evenly distributed.

Moreover, we talked about all the amino acids and the different intra-molecular forces that keep proteins from denaturing under normal circumstances.  The three main ones that we touched upon in class were; Hydrogen bonding, “pie-stacking”, and disulfide bonds.  Disulfide bonds are by far the strongest bonds.  They are commonly seen in bread.  Another fun fact about amino acids is that proline, which is categorized as a small amino acid, is very rigid due to its ring.  Thus, it cannot be involved in any alpha-helices and is most commonly found in gelatin.

img_0049Now for the fun stuff!  The heating of milk! I know it doesn’t sound like the most excited thing but don’t worry well get there.  Heating milk is how someone makes cottage cheese.  Cheese curds!  The heating separates the whey protein and curds.  The picture on the left shows the result for this reaction.  Now obviously the first part of this is to pour milk into a pot and turn the heat on.  Simple, right?  Then you just wait ad drain at the end and you have cheese curds and whey! All my life I always thought that whey was a solid  A lot of protein supplements advertise “Pure Whey Protein” and when you get the protein its solid.  So, without asking questions I just assumed that it was solid.  Sadly, I was mistaken.  Don’t believe everything you see on the internet! Except for this blog! 100% facts.

Another misconception I had was that the only way to make butter was to churn it.  Again, sadly mistaken.  We made butter in a mason jar.  Yes, you read that correctly.  Agitating the butter in the mason jar allows the fat globules to coagulate and form a solid.  That solid is butter.  Emulsifiers hold the fat globules together.  They have a hydrophilic end and a hydrophobic end.  The hydrophilic ends are water soluble while the hydrophobic ends are fat soluble.  Using the same chemistry, we also made butter in a kitchen aid!  Now this was not as much as a workout as making butter with a major jar but ended up producing the same product.

 

img_0047

The last and final experiment that we did was heating butter!  The butter was introduced to the heat and was stirred continuously for about 10-15 minuets.  The butter turned from solid to liquid and then back to solid!  The water in the butter evaporated and we were left with the butterfat, milk solids and lactose. Now, when we continued to heat up the now butterfat, milk solids and lactose the sugar begins to turn color and brown.  Similar to the caramelization’s that we did last week that Jack told you all about.  Besides making butter in a mason jar, which really shook me up, I thought this was the coolest reaction of the day.  I especially liked how it brought us back to the last class because it doesn’t matter how food starts, once you break it back down to one of the basic 4 food groups, everything remains constant.  Finally, to end the day, the class got to enjoy a variety of different cheeses that all had something special about them.  By the way, did you know that cheddar cheese came from the town of Cheddar, England?  That’s our fun fact of the day.  Thanks for tuning in to our class blog and be sure to stop by again next week to learn more about meats!

Sugar, We’re Goin Down

Sugar

 Sugar and sugar rich foods are now among the most popular and widely consumed foods in the world. From corn syrup, raw sugar, refined sugar, or sweeteners its hard to pick something off the shelf in a grocery store and not find some type of sugar in it. Humans have developed a natural sweet tooth that stems from our first taste, breast milk. We constantly crave and love the sweet flavor that sugar adds to so much of what we eat and drink.

imgres-1.jpg

Sugar Cane

There are four main types of sugar, glucose, fructose, sucrose and lactose. Glucose is a simple sugar and the most common sugar from which living cells directly extract chemical energy. Glucose is the starting point for one of the most important reaction in humans, glycolysis. Lactose is the main sugar found in milk. However most sugar found on tables is actually sucrose.

imgres.jpg

Refined Table Sugar

In Class this week we looked at some of the chemical structures of sugar and how they change. We then decided to experiment through the process of making caramel. To start, sugar was placed in a pot and was slowly heated while constantly stirring. There are two main ways of making caramel, a dry method and a wet method. In the dry method, solid sugar is placed in the pan and heated until the sugar molecules start breaking apart.img_1207

In the wet method, sugar is dissolved in enough water to look like a white mud and then heated. The water acts as a buffer that allows the pot to be heated at high temperatures without burning the sugar.

img_1214

As the heat rises, the sugar will begin to burn, right before this moment, is when you want to add the cream. img_1218

The color of the sugar comes from the break down of sucrose and the production of hundreds of new and different compounds that also give the caramel bitter and sweet tastes. Cooked to long and the sugar will burn and become very bitter.. This caramelization reaction is not a form of a Maillard reaction which we discussed and saw in our chicken fat cooking.

img_1204

Overall, it was a great first week. From eating chicken feather to tasting salted caramel with a little pot* in it, the chemistry of food is exciting and never ending. More to come soon.

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?

Untitled

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?

plates

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.

ppl

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.

Screen Shot 2015-05-10 at 4.51.55 PM

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.

Screen Shot 2015-05-10 at 4.52.57 PM

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.

Screen Shot 2015-05-10 at 4.54.22 PM

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.

Screen Shot 2015-05-10 at 4.55.05 PM

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.

http://natural-fertility-info.com/wp-content/uploads/GMOLabels1.jpg

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:

IMG_5381

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:

IMG_5378

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

IMG_5385

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.

pic 1

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.

pic 2

pic 3

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.

c470886faf62689519573e9fb8587dba

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.

pic 5

pic 6

pic 7

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.

pic 8

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)?”