Tuesday, March 26, 2013

Science and Cookies and Tea

Last week, NPR reported on a momentous scientific breakthrough: ultra-modernist chef Heston Blumental found that cookies really do taste better when dipped in tea.

Using a specialized mass spectrometer called the MS-Nose, Blumenthal's team measured the release of aromas when subjects bit into dry and dunked cookies. Mass spectrometry, or MS, is a way of determining the molecular composition of a sample. And because smell is so closely linked to how we taste, aromas are a reliable indicator of flavor.

They cited methylbutanol as an important player in the perception of cookie flavor. 2- and 3-methylbutanol are higher ("fusel") alcohols characterized by their malty, toasty, or burnt flavor. These compounds are also found in certain nuts and in ripening fruits.

In the interest of science, I decided to test my own appraisal of flavor with some hot tea and a batch of cookies fresh out of the oven. For my materials, I chose Easter cookies and four different cups of hot tea: English breakfast black, rooibos (red), a pumpkin spice blend, and my current obsession, a cardamom-cinnamon spice brew.

The cookies are so named because the tiny currants look just like Easter Bunny poop.

Kidding! They're called Easter cookies because that's what my cookbook calls them; apparently they're a traditional Lent-is-over-and-you-can-have-butter-again treat.

Hypothesis: The release of flavor from cookies is greater when they are dunked in tea rather than eaten dry.

Methods: First, bake cookies according to the recipe at the bottom of this post. When test specimens have cooled, boil water and prepare tea. Break one cookie in half and subjectively compare the release of flavor following consumption of the half eaten dry (A) to the other half dipped in tea. Repeat trials as necessary to collect sufficient data.

Results: The flavors of the herbal tea blends overwhelmed the cookies when specimens were dunked, although mouthfeel was improved (the test subject found the cookies to be a bit dry on their own). Satisfactory results were obtained with cookies dipped in black and red teas, i.e. cookie flavor seemed to improve following momentary submersion in these liquids.

Conclusions: Preliminary results agree with the findings of Blumenthal et al. However, the qualitative nature of the analyses presented herein must be taken into account. Further testing would unfortunately require laboratory equipment that just wouldn't fit in the author's already cramped kitchen.

Blumenthal's research leaves many questions unanswered. What exactly is it about dunking that releases flavor so admirably? Is it the moisture? The heat? Specific compounds in the tea? How long should a cookie be dipped for maximum flavor? Would hot water work just as well? What about cold drinks? Does the classic American combo of milk and cookies produce similar results? How do different cookies compare?

Scientists, if you're looking for willing volunteers to help address these crucial research gaps, give me a call. I'm more that willing to do my part.

(Recipe behind the cut...)

Easter Cookies
Recipe adapted slightly from The Cookie Book
Yields 14-16 cookies (if using a 5cm (2") fluted round cutter)

Note: I made these cookies by weight, not volume. Volumetric measurements are from the cookbook. I've previously found that my cups of flour weigh a bit more than theirs, so you may need to add more milk to the dough in step 2 if it's too dry. 

115g (1/2 cup) butter, room temperature, diced
75g (scant 1/2 cup) sugar, plus extra for sprinkling
1 egg, separated
200g (1 3/4 cups) all-purpose flour, or a mix of white and whole wheat pastry flours
1/2 tsp each cinnamon and apple pie spice*
50g (1/4 to 1/3 cup) currants
15-30ml (1-2 Tbsp) milk

*If you don't have apple pie spice, use 1/4 tsp ginger, 1/4 tsp nutmeg, and a pinch each of allspice and cardamom.

1.   Preheat the oven to 400˚F. Beat the butter and sugar in a bowl, then add the egg yolk.

2.   Combine the flour and spices and add to the butter mixture in several additions, beating at low speed until just combined. Stir in the currants, adding just enough milk that a clump of dough holds together when pinched; it will still look a bit crumbly.

3.   Roll the dough out onto a floured countertop until it's about 5mm (1/4") thick. Stamp out rounds with the cookie cutter of your choice.

4.   Transfer cookies to lightly greased baking sheets and pop 'em in the oven for 10 minutes. Meanwhile, beat the egg white with a fork for a minute or two.

5.   Remove cookies from oven. Brush the tops with the egg white, then sprinkle with sugar (I recommend only brushing one or two at a time so the moisture doesn't cook off before you dust them with sugar).

6.   Return to the oven and bake 10 more minutes (less on a dark cookie sheet—compare the two pans below). Let cool briefly on the baking pans, then move to a wire rack to finish cooling. 

1 comment:

  1. haha! fun read, Amy. And that cookie recipe looks divine.