Principles

A collection of cooking notions, especially scientific ones, that so far defy categorization on this site.

Extracting flavors

Food flavors derive from different sources and require the use of different solvents, primarily water and oil, to extract them. It is essential to understand which solvent to use to coax flavor out of a spice, aromate or some other ingredient.

Why, for example, isn't it possible to extract much flavor from either ground black pepper or red pepper flakes when were added to a brine or room-temperature marinade? Their flavors blossom, becoming deep and fragrant, after being briefly steeped in warm oil. It's simply a matter of solubility.

The essential oils in both black pepper and red pepper flakes are oil-soluble as opposed to water-soluble. This means that they dissolve in oil rather than water. As they dissolve, their flavorful essential oils are released from a solid state into solution form, where they mix and interact, thereby producing a more complex flavor. Like most substances, these essential oils dissolve faster and to a greater extent in a hot solvent (in this case, olive oil) than in a cold solvent. However, if the oil is too hot, the spices can scorch.

In five batches of marinade tested by Cook's Illustrated, bringing them to temperatures of 150°, 200°, 250°, 300°, and 400°, the differences were dramatic. The 150° batch tasted flat and boring, while the marinades brought to 250°, 300°, and 400° tasted increasingly burnt. When heated to 200°, however, the marinade tasted perfectly spicy and well rounded.

Moral: solvent and temperature are critical!

Reactive cookware

Plain aluminum pots react to foods, especially acidic ones. They have no place in the kitchen, but especially should not be used to cook artichokes or marinaras.

Anodization hardens aluminum and makes it non reactive. It also imparts a dark color to it. Calphalon is one of the more famous manufacturer of good-quality anodized aluminum cookware for home and commercial kitchen.

Plastic versus wood cutting boards

In a study by Cook's Illustrated it was determined that there is little difference between plastic/nylon and wood cutting boards for cutting meats and other things that spoil. However, it is a good idea to clean any cutting board as immediately as possible.

My own personal opinion is that plastic is a better material to abuse because a) I still don't buy that porous wood doesn't foster more bacteria (despite the report) and b) plastic is cheaper and I regret less throwing it away when it becomes foul. Here is the report:

 

In 1994, a research report was published that proved to be the opening salvo in a long battle over which material was more sanitary for cutting boards, wood or plastic. The researchers found that fewer bacteria could be recovered from wooden boards infected with live cultures than from plastic boards treated the same way. These results caused the researchers to question the prevailing view that plastic was more sanitary than wood; some have further interpreted the data to mean that wood is, in fact, a safer material for cutting boards. In a report that followed, researchers at a U.S. Department of Agriculture (USDA) lab concluded that beef bacteria on polyethylene and wooden cutting boards had statistically similar patterns of attachment and removal. Even so, the idea that wood is more sanitary than plastic persists and was recently reaffirmed in the food section of the New York Times.

So What's on Your Cutting Board?

We wanted to get our own perspective on the problem, so we asked four staff members to donate their used boards, two wooden and two plastic. We found very little bacteria growing on these boards when we sampled them, so we took the boards to a local lab to have them artificially inoculated with bacteria. The procedure worked as follows: A drop of the medium containing millions of bacteria was placed on the boards, the boards were left to sit for 40 minutes to allow for absorption of the bacteria, and an attempt was then made to remove the bacteria. In repeated tests, between 6.0 percent and 8.1 percent of the bacteria were recovered from the plastic and between 1.3 percent and 6.2 percent from the wood. Given that the number of bacteria recovered from each type of board was well into the hundreds of thousands, there was little to assure us that one material was much safer than the other.

Soap and Water to the Rescue

Scrubbing the boards with hot soapy water was a different story. Once the contaminated boards had been cleaned, we recovered an average of 0.00015 percent from the plastic and 0.00037 percent from the wood?or fewer than 100 bacteria from each board. In a related test, we were able to transfer bacteria from contaminated, unwashed boards made from both wood and plastic to petri dishes using potatoes and onions. But our most surprising discovery by far was that the bacteria could persist on unwashed boards of both types for up to 60 hours!

What, then, is the truth about cutting boards? Both plastic and wooden boards can hold on to bacteria for long periods of time. Both plastic and wooden boards allow for transference of bacteria to other foods. Luckily, we found that scrubbing with hot soapy water was an effective (though not perfect) way of cleaning both kinds of boards; the USDA also recommends the regular application of a solution of 1 teaspoon bleach per quart of water. Simply put, maintenance, not material, provides the greatest margin of safety.