The Tech - Online EditionMIT's oldest and largest
newspaper & the first
newspaper published
on the web
Boston Weather: 33.0°F | A Few Clouds

Gourmet Geek

Lactolicious

By Rose Grabowski

Milk and cookies have long been a staple of most children's existence. It was an after-school snack when we were younger, and as we grew into college-aged “adults,” it has become a midnight nibble n’ swig to prepare for a long night of p-sets and labs.

But what was once a luscious grouping of whole milk and friendly fresh chocolate chip cookies has more often evolved into skim milk and brittle, low-fat off-the-shelf biscuits in this health conscious and I-will-lose-that-freshman-fifteen-damnit environment.

So when a friend of mine returned from the store and pulled out his Lactaid and Chips Ahoy, a few of us were quite shocked. Our sacred duo had been adulterated to the point that milk was no longer even a component. Another friend accused him of drinking chemicals, not milk. She claimed Lactaid had no place calling itself milk (the carton does indeed say “real milk!”) because the whole concept behind Lactaid is that lactose, the milk sugar, has been removed, and how can milk be milk without milk sugar? And thus commenced a 40 minute argument about the nature of milk. We never came to a consensus. However, being the food nerd I am, I decided a complex and decisive analysis was in order to dispel any myths about Lactaid and milk.

It turns out that milk is not just lactose and water -- those are actually some of the least important elements. Milk also includes vitamins, minerals, fats, and complex proteins. The fats include fatty acids and lipid-soluble vitamins and provide about half the calories of the whole liquid. The proteins include curd (or casein) proteins and whey (or lactoglobulin) proteins. Yes, think Little Miss Muffet.

These proteins are the most nutritional and critical parts of milk. The fats provide some of the texture and lactose provides much of the flavor, and together they provide most of the calories. However, fats and lactose are not essential to milk.

We generally accept the 1 percent and skim versions as the real deal, and the flavor provided by lactose can reasonably be approximated by other sugars. Lactose is not even exclusive to milk -- it can be found in forsythia flowers and a small number of tropical shrubs. The proteins are what enable the derivation from milk of other dairy products and distinguish the liquid so essentially from any other.

So, since Lactaid is just milk minus the lactose, it may indeed claim the title of milk. Although I’m guessing it doesn’t go as well with Oreos as the alternative. The question then becomes why would people drink Lactaid at all? Obviously it has something to do with lactose intolerance, but there are a few intricacies to that label that are worth exploring.

Humans are the only animal that have the ability to drink milk after infancy. However, the vast majority of humans don’t even have this ability (or, really, don’t have this abnormality.) Lactase, the enzyme that breaks down the lactose disaccharide into glucose and galactose, usually peaks in concentration in the human stomach shortly after birth and reaches a steady minimum when a child is between one and a half and three and a half years old.

Evolutionarily, this makes perfect sense, because most mammals would not come upon milk after this stage of life. Producing an enzyme to handle it would be a waste of resources. When lactose is ingested without the presence of lactase, bacteria in the digestive tract still metabolize it. However, instead of making the sugar useable, they ferment the lactose, producing carbon dioxide and a decidedly unpleasant feeling in the mammal’s body (read: flatulation). So this is what happens to most adult humans when they ingest too much lactose and the bacteria get a boon to their food supply. The rest of us keep producing the lactase and digest lactose just like any other regularly digested item.

However, despite the label that so many people assume, most lactose intolerant people are actually able to consume substantial amounts of dairy products without effect. Most can drink up to a pint of milk a day, and since cheese and yogurt are virtually free of lactose because the culturing process (once again, fermentation) uses lactose for fuel, those cultured dairy products are fairly easy to digest.

So maybe my friend wanted to consume more than a pint, and that’s why he chose Lactaid. Perhaps he is on the less tolerant end of the spectrum and really can’t consume much dairy at all. Maybe he just likes Lactaid better than regular milk... but, in any case, at least there’s a real-milk option for the huge portion of the population that needs to avoid lactose -- I mean, how else would they down their Oreos?

If you have questions or areas of food science that you would like to see explored, you can contact me at roseg@mit.edu.