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Gourmet Geek

Something Rotten in the State of Denmark

By Rose Grabowski

The dairy family of foods has managed to consume my thoughts for the last few weeks. It seems that my love of cheese and ice cream is relentless in hammering the point of their origins in my brain.

First was the column “Lactolicious,” about the properties of milk and the product, Lactaid. Then, I received a message from a reader correcting me on some points. Glad to see that someone else was at least willing to engage in conversation about the exact properties of milk, it was kind of comforting to find fellow food nerds out there.

First, my statement that Lactaid is “milk minus the lactose” was not exact. Lactaid milk actually has lactase added to digest the lactose into glucose and galactose, making the drink more easily digestible.

Second, I inadvertently implied that Lactaid does not taste as good “as the alternative.” Well, ten minutes ago, I took a trip down to the convenience store and purchased the said product. Now that I have the fresh taste of milk and lactase in my mouth, I can more faithfully describe the sensation.

Lactaid actually seems somewhat sweeter than traditional milk ... quite a bit sweeter, in fact. Whodathunk? It also has an extremely faint, funny aftertaste, almost like a Vanilla SlimFast shake without the vanilla. But those are basically the only differences that I can detect.

However, after this experience, I would like to reassert my claim that Oreos may go better with normal milk, based on the likely-common preference for consuming slightly contrasting foods together.

So as I reached into my fridge to compare the Lactaid to the Hood, I unpleasantly recalled the typical plight of the hosed MIT undergrad.

This week, I have been too busy to consume a lot of the perishables in my food stock and the milk that I had bought two weeks ago has been sitting around a wee bit too long.

Today’s American milk is almost always pasteurized and homogenized. Pasteurization is a process of heating milk to kill microbes and denature native enzymes which would break down milk fats and deteriorate the taste.

Homogenization is a pressure treatment that disperses fat globules evenly in milk so that cream doesn’t rise to the top and sink thin watery materials to the bottom.

However, even with all that, it turns out that all milk, even the stuff you buy in nice white bottles at a high-end grocery market like LaVerde’s or Star, has millions of bacteria in every half-gallon. If left to their own devices, those bacteria would digest a lot of the lactose surrounding them and release lactic acid as a by-product. Hence, the sour 2-week-old milk in my fridge.

Refrigeration obviously helps the problem in general, although the ideal temperature to prevent the bacteria from dominating your breakfast drink is just above freezing, a level not easily feasible by the typical college student (or non-professional chef, for that matter.)

To maximize the life expectancy of the dairy products in your cube fridge between trips to the Athena cluster, be sure to follow as many of these guidelines as possible:

Pick milk that is freshest. Take the 20 seconds it requires to check the date on the milk (you know it has an expiration date printed, right?) before you buy, and find the carton with the latest date.

Don’t drink out of the carton. First of all, it looks gross. Girls don’t go for slobs. Second, there are just an ungodly number of bacteria around your mouth, whether you’re a prude or a ho.

By putting your mouth to the carton, you are exposing the milk to all of that bacteria which will digest the sugars and sour your milk many times faster than the native bacteria. And third, it’s still gross.

Keep your milk out of the light. The energy in light oxidizes the fats and fragments the hydrocarbon chains. These rouge chains tend to be very volatile (read “smelly”). Indirect sunlight is plenty to cause this oxidation, but direct sunlight will also add “sunlight flavor,” a burnt cabbage taste caused by a reaction between an amino acid, riboflavin, and methionine.

Keep the milk as far into the back of your refrigerator as possible, as much as possible. The more heat, and especially bursts of heat, the milk is exposed to, the faster it will sour. But “heat” does not mean “stove” -- it means any temperature more than 39°F. The worst place of all to place your milk is on the door. Again, take the 20 seconds it requires to stick it in the fridge properly.

So what happens if your milk sours? Sometimes people think it’ll get them other dairy products like cheese or yogurt. Not quite, but nice try. You just get sour milk.