Twinkie, Deconstructed (27 page)

Like politics, food science makes strange bedfellows, mixing odd ingredients and yielding even odder results, and butyric acid takes the cake for odd. This flavor, a natural component of Parmesan cheese, rancid butter, and, unbelievably, vomit and perspiration, is made by passing carbon monoxide, not quite your usual food ingredient (but a great source of carbon, hydrogren, and oxygen in a reaction), over a mixture of sodium metal catalysts at 400°F. The result is an oily, colorless, foul-smelling liquid that eventually suggests…butter.

A touch of milky, creamy, waxy coconut, and peach or plum notes are added by mixing even more petrochemicals—a bunch of lactones, the most prominent of which has the great, long name deltadodecalactone. This fragrant, translucent yellowish-green, somewhat toxic, highly flammable liquid is handled with special care at the flavor company because, should it spill, the smell would be extraordinarily difficult to clean up. Of course, once it is processed, chemical reactions totally neutralize any toxicity and flammability.

With these unlikely ingredients, Twinkies’ butter flavor is created—quite literally—out of gas. It joins the two versions of vanilla and with them evokes or creates those wonderful childhood memories that, in part, drive Twinkies’ popularity. Luckily, only a little is needed—the flavors are blended into the batter so artfully by one of the world’s best emulsifiers, an ingredient made from two vegetable acids and a caustic liquid that started out as table salt.

CHAPTER 21

Sodium Stearoyl Lactylate

I
t is hard to say what SSL actually is or what the home equivalent is. And yet, sodium stearoyl lactylate is the ingredient that gives bakers the most bang for their buck. If they had to choose one additive to use in a bakery, it would be SSL (as it’s known to the cognoscenti), for its surprisingly multifaceted nature. Whatever it is, exactly, its ingredients come from all over the country, and possibly the South Pacific. And here you thought vanilla was exotic.

T
IGHTENING AND
W
HIPPING
U
P

Like a good mate, sodium stearoyl lactylate offers both strength and softness, unlike other additives, which are capable of providing only one or the other. In keeping with its tendency to overachieve, SSL starts working before a batter is even baked, acting as a “dough conditioner,” stabilizing and strengthening it and improving the protein, simply making it easier to manipulate. Then, both before and during cooking, even though it is more of a fat, SSL functions as an emulsifier instead: it helps to tighten and increase the volume of the crumb, partly by helping to retain the gas created by the leavening. (Think Wonder
^®
Bread as opposed to an airy French baguette.) In coffee whiteners (artificial creamers), puddings, and low-fat margarines it also acts as an emulsifier. It “complexes” the starch, keeping bread softer, longer (this is antistaling; though it is not considered a preservative, SSL certainly helps preserve Twinkies by extending shelf life). Finally, it works as a whipping aid and so creates creaminess in the Twinkie filling (along with polysorbate 60), which is why it is often found in cheese sauces, cream liqueurs, and Hunt’s Snack Pack Vanilla Pudding (and in Jell-O
^®
Pudding Snacks, too, emphatically described as being “for smooth texture”). Despite this heroic list of attributes, the powerful SSL remains a minor ingredient, usually less than 1 percent of a flour mixture like Twinkies, making it quite inexpensive.

A totally fabricated additive, it still most closely duplicates the humble egg yolk in home recipes. Food scientists and product developers will tell you (as they repeatedly told me) that SSL is a whole lot better than eggs, and, for that matter, better than Better’n Eggs
^®
(which has no yolks, either). All it takes to make it is some rocks (sodium) from Wyoming, palm trees or soybeans (stearoyl) processed in Massachusetts, corn (lactylate) processed in Nebraska, and a big processing facility in Missouri.

A Dash of Salt?

The first subingredient, which lends the “sodium,” to sodium stearoyl lactylate, seems common enough, but in fact turns out to be the one part of the recipe that approaches secret status. That is surprising also because the sodium part of SSL, though listed first in the name, is infinitesimally small. However, it can and often does come from a small dose of soda ash (sodium carbonate)—the same raw material used to make sodium acid pyrophosphate—such as that mined and processed in Green River, Wyoming, by FMC. Shipped by railcar as a powder or a liquid to SSL manufacturers, the soda ash is unloaded by a giant vacuum or pump and stored in small silos. The sodium can also come from either solid or liquid sodium hydroxide (lye), made from salt as part of the chloralkali process, or even sodium methoxide, a toxic mixture of methanol and sodium hydroxide. For the open-minded scientists at an SSL manufacturing plant, such as American Ingredients in Grandview, Missouri, it makes no difference where the sodium comes from, so they choose based on availability and, of course, price. All the toxic chemicals get rearranged and neutralized in the upcoming reactions, anyway.

Candle Acid

Stearic acid, perhaps from Twin Rivers, in Quincy, Massachusetts, among other places, is the second name-giving ingredient in sodium stearoyl lactylate, and it arrives at the plant solid as a candle.
12
(The “-oyl” suffix indicates that something contains an oil or fatty acid.) On a single, private track in back of American Ingredients’ SSL plant, workers patiently pump steam into the outer jackets of a few tank cars in order to liquefy this fully hydrogenated oil, which melts at 170°F. With 160,000 pounds in each car, it takes twelve hours to pump out a tank car, even using a six-inch-wide hose.

The River Effect

In a darkened, quiet area of a sterile pump, pipe, and tank loft of Cargill’s corn biorefinery in Blair, Nebraska, where corn sweeteners of all kinds are made by the ton every minute from Midwestern field corn, a nondescript, eight-inch-wide pipe extends through the wall, carrying corn syrup full of sugary dextrose. A white steel truss supports this pipe from the corn syrup plant, across the industrial campus’s parking lot, and over to some bright steel towers at the lactic acid plant. The air smells sweet. An old farm’s windmill turns slowly in the distance, calling to mind the Netherlands, the headquarters for the world’s largest lactic acid manufacturer, Purac, which happens to own the plant I’m about to enter.

Attached to the plant buildings is a solid, new, cement-paneled office building, which looks like it could withstand any form of extreme weather the Great Plains might throw at it. (Later on I learn that my hunch is right; it doubles as a tornado shelter.) The plant manager, a scientist-brewer named Kevin Shoemaker, provides a whiteboard tour of biochemistry via a three-color, thirty-two-box flowchart that he draws from memory. Waypoints on the board tour include fermentation, calcification, biomass separation, swap reaction, dilute lactic acid, purification and concentration, and finally, lactic acid. This is not a walk in the park, or, since we’re in rural Nebraska, a stroll in the field.

Lactic acid, the third name-giving ingredient in SSL, is a natural acid, one type of which is made in our bodies by bursts of muscular activity. It is what makes your muscles feel sore and tired and gives you cramps in your side when you’re running. (It seems appropriate to reflect on this as I climb up and around the lactic acid plant and feel the burn in my thighs.) It also occurs naturally due to the fermentation of sugar in foods ranging from sauerkraut to meat. Lactic acid is responsible for the sour taste in spoiled milk and the sour taste in cheese (and Cheetos
^®
too). Unsurprisingly, its name comes from the Latin word
lack
, meaning “milk.” Carl Wilhelm Scheele, the great Swedish chemist, first isolated lactic acid from sour milk in 1780, and this former waste product has been used to make food ever since. But the lactic acid made for food use, for use in Twinkies, is not made from milk—it’s made from dextrose, a corn syrup.

Lactic acid, like salt, brings out savory flavors in beverages and foods and, as such, has long been used as a preservative in processed meat and poultry. While helping to enhance flavor, it also stabilizes and preserves salad dressings. It extends shelf life and helps fix the color of pickles, olives, and other brined vegetables. On the sweet side, it is a staple of hard candy and fruit gum. It is a natural sourdough acid, and, of course, it plays a role in cake recipes, too, either as an acid itself, or, as with Twinkies, as part of the versatile emulsifier SSL.

Lactic acid is utilized in a number of fascinating and totally unpredictable ways in industry, too, ranging from tanning leather to making CD ROMs. And it is made from renewable resources. Purac seems to have found a good business to be in; its parent company reports sales of $5 billion a year.

Outside, the dextrose pipe from the corn syrup plant leads to the fermenters, a small group of closed, cylindrical towers, each about one story high, surrounded by a mass of pipes and valves. First, the dextrose is piped into the towers along with a little benign bacteria to start the fermentation, just like yeast is used to make beer (as with beer, the choice of bacteria is key, and here, it’s top secret). In one corner stands a little silo, from which lime is fed in with the bacteria as needed to control the fermentation’s pH level. The lime is likely to come from the Mississippi Lime Company, the same place that supplies it to many other food processors for items like monocalcium phosphate.

The result is a nice broth of calcium lactate (the product of the calcification stage), and, as is fitting, the first tank it is piped into is called the “broth surge tank.” Here the biomass created by the fermentation, the spent bacteria, becomes a useful waste product, as the crunchy, dry leftover is separated from the liquid—spun out in a centrifuge operation—ground up slightly, and in a nifty bit of true recycling, sold to local farmers as a nitrogen and phosphorus-rich fertilizer for corn. Brewers are always known to gardeners and farmers for their great waste products, and it’s no different here in Nebraska.

Next, sulfuric acid, one of the most common basic chemicals, is channeled through polypropylene-lined pipes for a quick “swap” reaction with the calcium that creates calcium sulfate, better known as gypsum, which is then precipitated out, along with every trace of sulfuric acid. Shoemaker reaches into a steel machine to grab a handful for me to feel. With the consistency of wet sand, this by-product is sold wet, locally, as a soil amendment, which makes sense for everyone, as it is more easily taken up by the soil that way, and would be costly to dry.

What’s left is dilute lactic acid, which travels through a series of concentration tanks and a forest of forty-foot-tall, ten-foot-wide, white, cylindrical, steam-heated evaporators for purification. The first few concentration tanks are linked heat exchangers known as effects. Looking something like a four-story-high, front-loading washing machine, the porthole at the bottom of each offers a clear view of the acid drying. What started out as a brown milk shake is now a clear, almost watery syrup.

Shoemaker interrupts the quality control lab momentarily to land me a sample of lactic acid. The startled technicians rummage around, and after ten or so seconds come up with a bottle of what looks to be water. It is too concentrated to taste, but just right for sniffing. “Sort of a mild sweet and sour?” I ask, hoping to get it right. “With a bit of caramel,” Shoemaker adds. A caramel note, indeed. “What do you think, Tony?” Shoemaker asks a young lab tech. I half expect him to say something like, “The 2002 had much more oakiness, with a hint of fruit,” but instead he replies, “Kinda sweet.”

No oak barrels for this wine. From the tank loft the fresh acid is pumped outside into a small farm of holding tanks, and then into a loading bay where stainless steel tank trucks and big black tank railcars stand ready to run it downriver to Grandview, Missouri, where it will be made into sodium stearoyl lactylate, along with the two other unlikely cake-mates.

B
LOWING
H
OT AND
C
OLD

Posters outlining the steps of how to brew complex Belgian beers line the walls of one scientist’s office at American Ingredients, part of the company that held the original patent on sodium stearoyl lactylate, from the early 1950s, and now one of the few specialized enough to make it. Beer brewing is food chemistry, too, though the process is slightly older, by thousands or tens of thousands of years. It also presents quite a contrast to the stainless steel–clad, computer-driven alchemy that the company works with—one step in the Belgian beer-brewing process calls for it to sit in open vats in old, spider- and dust-laden barns. We certainly won’t see
that
with any Twinkie ingredients.

The prairie wind blasts the plant (the same one that makes mono and diglycerides) but doesn’t disturb its compact tank farm, the smallest of which holds an intriguing substance: liquid nitrogen. The valves at the bottom are frozen in ice piles several feet high, despite the sun, because what’s inside is chilled to 350 degrees
below
zero Fahrenheit. A huge radiator, ten feet tall and twenty feet wide, warms it a bit en route to the plant so that it gasifies. This way it can be used as a blanket in the storage and processing tanks, driving out the oxygen and keeping these precious food fluids fresh.

Troy Boutté, American’s Director of Research and Development, is again my guide. Boutté helps me trace the pipes that carry both the stearic acid and the lactic acid inside and into stainless steel reactor vessels, each the size of a delivery truck. The mixer motors in each kettle are grinding away full tilt. The kettles are so big that it takes about six hours to fill them; the mix cooks for only about two hours. Bursts of steam punctuate the atmosphere while heating the giant kettles. A small shot of the sodium material—a soupçon of sodium carbonate or a similar alkali (whatever it is remains unidentified by my guides)—brings the reaction to a halt. Any caustic qualities are immediately neutralized by the base’s reaction with the two acids (stearic and lactic), which are themselves quite gentle. The result is a gentle yet fabulously useful salt, but at this point it is a hot, thick, fatty syrup, a white glop that is pumped over a slowly rotating ten-foot-diameter, stainless steel drum called a “flaker.”