Monday, December 30, 2013

Expansionist Knowledge - Fat (Article)

A couple decades ago, I was a single guy trying to navigate the educational waters of graduate school as I researched for nearly a decade in chemistry. That also meant that the financial waters were frequently turbulent. Not far from my apartment was an Entenmann's Bakery Outlet. I had been there many times in the past for a cheap goody. When I arrived on this day, I was first surprised by the long lines of people carrying large numbers of wide, short boxes to the checkout. As I looked passed them, I was next surprised to see a few tables loaded four or five feet high with these same boxes. So I went over to them. What a delight the signs for the tables held! The first moment of rapture: 25 cents per box. That was in my price range. Many was the time that the cheapest item cost more than the loose change in my pocket. I had then returned home empty handed but grateful for the brief exercise. But not today! Today, I would spend my money frugally and still give in to my sweet tooth. The second moment of rapture then hit me: Fat-free coffee cakes. Fat-free?!? This was wonderful! Sure, they were still loaded with sugar, which my body was all too likely to turn into fat. And there was even a good chance that there was more sugar in the fat-free coffee cakes than there were in the regular coffee cakes. Still, it was 25 cent per box and fat-free. Eagerly, I looked through the flavor options, selected out three boxes, and headed to the checkout line like a conquering hero with the Rocky theme playing in my head.

But now the conquering hero had time to think. What was in the coffee cakes in place of the fat? My mom had taught me that you could replace the oil in a cake recipe with applesauce. Had they done something of that nature? To satisfy my curiosity, I started reading the ingredients. Keep in mind, I am a chemist. I can read the nutrition labels with greater insight than many people in the general public. And that's when the it-is-too-good-to-be-true moment arrived with a thud that mentally and metaphorically beat me into the ground. There, plainly spelled out in front of my eyes were the two ingredients that unlocked the puzzle for me: mono-glycerides and di-glycerides. I was incensed. How could they do that? Was there no justice in the realm of prepackaged nutritional information? Why mock the person struggling with their finances and their health?

Why was I upset? Let's start with a little chemistry and chemical nomenclature. A "fat" is a triglyceride. There are three long chains of carbons. Each individual chain would be called a grease or an oil. Each chain ends in a carbon-oxygen-oxygen arrangement known as a carboxylic acid. The three chains are attached across a glycerol bridge. See Figure 1 below. 

Figure 1: Basic Structure of Fat
The ends and the jags in the zigzag line are known to be carbons to the chemist's perception.
Every carbon will have four bonds. Any bonds not explicitly drawn are understood to contain hydrogen.

If a chain of carbons contains all of the hydrogen it possibly can, it is called saturated. This will show in a chemical diagram as only single bond (single lines) between carbons. If some of the hydrogen has been removed from the carbon, it is called unsaturated. For every two hydrogen atoms removed from adjoining carbons, one double bond (double line) is created. When one double bond has been created, it is called mono-unsaturated. If more than one double bond has been created, it is called poly-unsaturated. In general, the more poly-unsaturated the better. See Figure 2 below. 
Figure 2: Saturated, Mono-unsaturated, and Poly-unsaturated Chains in a Triglyceride
But this relatively good unsaturated oil can have its character changed from good-natured unsaturated to “evil” saturated through a process of hydrogenation. “Hydrogenated” is another term to be aware of in the nutrition labels. For example, coconut oil is gaining some ground for its health benefits, many microwave popcorn rely on hydrogenated coconut oil. This reverses any value the oil contained originally. Although hydrogenated oils, like trans-fats, have been gradually decreasing as the general public becomes more educated, they are still out there.

Trans-fats come about because those aforementioned double bonds come in two possible structures (called conformers). There is the cis- conformation and the trans- conformation. In the case of the cis- structure, there is a V shape bent into the long chain with the point of the V being the double bond. In the case of the trans- structure, the chain continues in the same direction with a small plateau at the double bond. See Figure 3 below.
Figure 3: Cis- versus Trans- Structures
Granted, in real life, the long chains are, in fact, whipping and sliding and twisting around. They do not form straight chains as shown in these pictures above. But that doesn't change the nature of the chemical terminology that will help us understand the next step in the intellectual process that led to my emotional reaction.

Our bodies will attack the food we consume in several locations within the gastro-intestinal tract. Starches start down their digestive journey in the mouth thanks to the amylase in saliva. The products in this step of digesting starch are simple sugars. In the case of fats, our bodies start their digestion in the small intestines thanks to lipase, bile salts, and other aids. The products are mono-glycerides and fatty acids. That's right. Going back to the fat-free coffee cake. There were no triglycerides in the cake. So it was technically fat free. But they had replaced the tri-glycerides with things that either are or will still produce mono-glycerides. There is no nutritional benefit to mono-glycerides and di-glycerides over triglycerides. Triglycerides have 9 calories per gram. Mono-glycerides and di-glycerides have 9 calories per gram. If anything, the body is having to expend less energy to obtain access to the mono-glycerides when eating these fat substitutes.

We like the taste and texture of our fats and oils. I suspect that is something built into us. Fats and oils are rare in nature. When we come across them, they taste good. The second most important nutrient in our diet is sodium. We like the taste of our salt. Who came up with salted caramel? Come on! Really?!? I shouldn't talk. I enjoy yogurt dipped pretzels. But you get the idea. We like our fat. We like our salt. Put them together, you have things like potato chips. To borrow the catch phrase, no one can eat just one. Like sodium, fats and oils are rare in nature, taste incredible, and are too large a portion of the American diet. Something with a similar taste to fats and oils but able to be technically labeled "Fat Free" is going to get some attention, especially in the form of sales.

That was the hope behind Olestra and the potato chips that were brought to the American grocery market. It is now more of a footnote in the history of food commerce in the US. For a brief time, though, it was the Holy Grail of Fat-Free substances. The chemical idea behind Olestra was simple. Unlike the glycerol bridge of triglycerides, Olestra started with a sucrose molecule. Chemically remove all of the ends of the sugar and replace them with fatty acids. See Figure 4 below. The body's process of breaking down fats was now hampered. The digestive enzymes couldn't get at the head of the chains of fatty acids. It was too congested. But it tasted, cooked, and produced many positive characteristics of consumption so much like traditional fats, this was sure to be a winner. But it wasn't. A few people could taste the difference and didn't like it. Some people ended up with gastric issues because their body treated the olestra as a foreign agent by flushing the invader from their system. And then, worse still, initial studies on mice who ate Olestra showed they gained weight. And worse, any weight gain was not reversed when switching back to traditional fats. As a footnote to the footnote, Olestra was renamed and released as an environmentally-safe industrial lubricant. Olestra was done for, but not the games companies play with our food.

Figure 4: Olestra - Sucrose at the Center of 8 Fatty Acids

With the continual process of eating, we are faced with making many decisions and hoping we don't fall prey to any of those games. Reading labels is a good place to start, if we are aware that there are pitfalls. Leaving aside pitfalls such as my personal desire to add butter to my popcorn, even "butter-flavored" microwave popcorn, I want to take a quick look at some labels. Amid the days I was writing, editing, and sweating over this article, I noticed that we have both fat-free sour cream and light sour cream. The fat-free stuff is for me. The light sour cream is for everyone else. They insist the light is better than the fat-free. Of course, they are right. But I can eat a little more of something I still enjoy for the same amount of points. One tablespoon even registers as zero points on the Weight Watchers calculator. Salmon not tasting exciting? A little sour cream and herbs and a delight has arrived. Salmon being point heavy, fat-free sour cream is a good option for me. What do the sour cream labels exhibit?
Fat Free Sour Cream by Naturally YoursCultured nonfat milk, milk*, food starch - modified, contains less than 2% of: whey protein concentrate, propylene glycol monoester*, artificial color**, gelatin, sodium phosphate, agar, xanthum gum, sodium citrate, locust bean gum, potassium sorbate (a preservative), natural flavor, vitamin A palmitate
     * - adds a negligible amount of fat
     ** - ingredient not found in regular sour cream
Light Sour Cream by LucerneCultured pasteurized Grade A fat free milk and cream, modified corn starch, disodium phosphate, guar gum, carrageenan, locust bean gum, natural flavors, vitamin A palmitate
As I read these labels, I recognize that both companies are interested in keeping some of the fat in the sour cream. Fat-free sour cream has milk, but it comes with an asterisk. That makes it okay. Light sour cream has cream. Can't go wrong in terms of flavor when using cream. Starting at the starch, the companies have chosen ingredients, some identical, some similar, some completely different, to accomplish the same purposes: color, texture, appearance, nutrition, preservation. While the fat-free sour cream openly identifies one preservative, the light sour cream does not identify any. The people at both of these companies were nice enough to include the Vitamin A Palmitate. When it comes to Vitamin A, you are better of eating one carrot over a pint of sour cream for your Vitamin A. Vitamin A Palmitate is close to useless. More on that in another article. But even as a chemist, I cannot answer the question, "What is the 'natural flavor' added to sour cream?" I am quite curious to know what that is. Is there an Essence of Sour I have yet to learn about? In the case of the fat-free, could the "natural flavor" be cream? Because of the asterisks, I suspect not. But I don't know. Notice in the light sour cream, the ingredient natural flavors is plural. What other essences, extracts, and additions can be deemed "natural" when it comes to sour cream?

But there is something hidden in the fat-free label that the company has even provided a clue. I may be somewhat derisive of the asterisks in my above comments, but the clue is in the *. There is the ingredient "propylene glycol monoester." And it has a single *. At first read, I thought this was a typo. Surely it should have had the double **. But companies can be quickly sued for errors and omissions in our litigious society. A vegetarian group won a suit against McDonald's a few years ago when it was revealed that "natural flavoring" for the cooking oil for their french fries included flavors from beef. Since the fat-free sour cream packaging has been around for quite some time, I began to doubt the possibility of a mistake. I went back and read the label again. There is the all important "monoester" in the ingredient name that changed a few things.

We all know that water and oil don't mix. They just don't play well together. But a third entity that is a friend to both can make a three-part mixture that has them all playing well together. This third entity is known as an emulsifier. One way to create an emulsifier is pick something that likes water, say propylene glycol, which among its other uses is as an environmentally friendly antifreeze for our cars. And then pick something that likes oils, say fatty acids. And then force them to merge. That is the propylene glycol monoester. Something our body will break down into propylene glycol and fatty acids. Propylene glycol and fatty acids are quickly metabolized by our bodies. But the single asterisk wasn't a typo. There really is another source of fat in the ingredients.

Does all of this information concerning the list of ingredients matter? There are two important aspects of this information in my opinion. First, the more knowledge we have, the better informed we are when making a decision. And since we are what we eat, knowing what we are putting in our mouths for our bodies for building blocks is important. Second, it helps to be a little suspicious. Not paranoid, mind you, just suspicious. Where that knowledge comes from can be more important than what that information is. The information is there on the label if you know how to interpret it. Use me as an initial resource as you collect your own information and draw your own conclusions. That is the scientific method in action, after all. That is why I invite the reader to become their own best advocate for their intellectual resources and physical health. 

I was trying to aid a little of my emotional and mental health when I purchased those fat-free goodies all those years ago. And I exercised my intellectual resources to explain what "fat-free" actually meant. And then I exercised my right to free speech in that store. And then the manager exercised his right to refuse service. It was something out the ironic to be expressing the failings of the very item I was purchasing. The primary failing being all of their coffee cakes were high in sugar. The manager was nice enough to let me purchase the goodies. I was nice enough to calm down.

Be your own best advocate for your health! - Eliot from the Expansionist Knowledge articles
Posted: 20 December 2013
(c) 2013, Scientific Consulting Services

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