What I Learned Today

I posted previously about a dramatic biscuit failure I experienced when I forgot to include baking powder, due to a careless reading of the recipe. Instead of regular flour, it called for “self-rising flour”, which already has baking powder mixed in. The strange thing is, no one seems to agree on exactly how much baking powder should go into self-rising flour. Casual googling turned up recommendations for 0.5 tsp, 1 tsp, 1.25 tsp, and 1.5 tsp (same as 0.5 Tbsp) as the amount of baking powder to add for each 1 cup of flour.

Now the difference between 0.5 and 1.5 tsp may not sound like a lot, but consider that it represents a 50% increase or decrease from a middle value of 1.0 tsp. For something as sensitive to stoichiometry as baking is, I’d expect that to make a difference. Then again, it seems reasonable that the desired amount would vary depending on the item being baked and how much loft you hope to get — which sort of defeats the purpose of a pre-mixed flour-baking powder product.

But even specialized biscuit recipes disagree on this, but seem to choose either 1 tsp or 0.5 Tbsp (1.5 tsp, in agreement with my mom’s recipe). (As a side note, they also vary widely on how much shortening or butter to use, as well as how much milk or buttermilk to use and whether or not to chill the dry ingredients + butter. The number of permutations sent me into a brief paralysis (gosh darn it, shouldn’t we have converged on a solution by now?!) until I decided to give up on the web and just use my mom’s recipe.)

I decided that a scientific test was called for. I split up the flour involved in a batch of biscuits (2 cups) into three bowls, for baking powder:flour ratios of 1 tsp:1 cup, 1.5 tsp:1 cup, and 2 tsp:1 cup. There was enough material to make two full biscuits of each type, plus some extra left over for a partial-biscuit. I measured the biscuit height before and after baking. The following chart shows the average (across two biscuits) difference in height I observed (data points in blue, average in red).

A clear difference emerged! It’s even almost linear, which is a bit surprising given the small sample size. Now it would be interesting to try even smaller and larger amounts of baking powder… the curve is likely to have an interesting shape at both ends. But for food, one of the most important measures of success is not size, but taste. I sampled all of the results and found that I couldn’t really tell a difference between the 1.5- and 2-tsp results, but the 1-tsp biscuits were noticeably less fluffy. I conclude that the wise biscuit baker should avoid self-rising flour with less than 1.5 tsp of baking powder per cup of flour (or avoid it altogether and just add your own ingredients).

Some other notes:

• One of the annoyingly tedious parts of making biscuits or scones is the “cutting in” step that gets the fat (butter or shortening or whatnot) into the flour. I used a tip from my friend Evan: freeze the butter, then use a cheese grater to shred it into the flour. Mix with fingers. Works like a charm!
• Some biscuit recipes call for milk, some for milk with lemon juice added, and some for buttermilk. Ever wondered why? Well, adding lemon juice or using buttermilk lowers the pH of the liquid (makes it more acidic). And chemical leaveners such as baking powder and baking soda are basic, therefore in theory should react more strongly in an acidic environment (giving your baked good more “rise”). But baking powder is baking soda pre-combined with its own acid (cream of tartar). So you shouldn’t actually need an acidic liquid. I tested this by dropping some baking powder in water, then in buttermilk. If anything, the baking powder reacted more to the water than the buttermilk. (I should do the same test with baking soda.) This also explains (maybe) why some recipes use baking powder and others use baking soda + cream of tartar — the latter want control over the ratio, just like the self-rising-flour issue!
• Biscuit aficionados recommend the use of flour with a lower protein content (to get even more loft) such as cake flour; see How to make the best Buttermilk Biscuits from Scratch. I haven’t tried this one yet, either.
• I actually did a parallel experiment, with the same three types of mixtures, but first chilling the dry ingredients + butter. However, a distraction at a critical moment caused me to forget to measure the biscuits before they went into the oven! So I only have their post-baking heights. If anything, the relationship seemed weaker, with less rising action. While a firm conclusion should await more reliable data, for now I’m going on the assumption that the chilling step is unnecessary. (Taste is unaffected, too ;) )

Clearly, the field of interesting experiments with ingredient combinations is a rich and open one, even just for making biscuits!

I adore peanut butter. It’s tasty on toast, on celery, on bananas, on Ritz crackers, on chocolate, and pretty much most other things. But of course, it is also high in fat, so I try to rein in my peanut-butter tendencies when possible. Low-fat versions of most foods are available, but I always wonder about the impact on taste.

The other day at the store I noticed a sale on Skippy peanut butter, my favored brand. In fact, the 16.3-oz containers were cheaper, per ounce, than their 32-ounce brethren that I normally buy. So it was the perfect chance to pick up a sample of both regular Skippy and the reduced-fat version for a side-by-side taste test.

As I opened up the containers, I wondered how exactly you could, in fact, reduce the fat in peanut butter. Although commercial peanut butter does have added oils “to prevent separation”, most of the fat actually comes from the peanuts themselves. How do you get a low-fat peanut? Answer: you don’t! While of course I don’t have the recipe that Skippy uses, perusing the ingredient lists of the two products suggests that you reduce the fat by… diluting the peanuts. The same non-separation oils are used, but reduced-fat peanut butter also comes with “soy protein” and “corn syrup solids” not present in the regular variety. The total protein per serving is the same in both products, so I can only imagine that the soy protein is there to make up the balance after diluting the peanuts (and their protein). The corn syrup solids are apparently there to make the product sweeter — and in fact the nutrition label reports more sugar (4g vs. 3g) in the reduced-fat version (cf. the regular version).

But numbers aside, what of the taste test? I grabbed a banana and spread one swath of peanut butter per bite, as I normally do, but alternated which peanut butter I used. There is definitely a difference. I worked my way through the whole banana to ensure I had enough samples to convince myself that it wasn’t just my imagination. I also did a pure test with no banana to evaluate them in isolation. Both products are equally creamy (thank you filler oils!), but the flavor in the reduced-fat version is slightly wrong. It’s blander, and I’m left with a certain after-taste that reminds me of the after-taste I get with food containing artificial sweeteners. It really isn’t as satisfying, which is what you’d expect based only on the fat difference — but there’s a definite taste difference as well.

So, yes, to a first approximation, the reduced-fat peanut butter still tastes like peanut butter. But after finishing a reduced-fat peanut butter banana, I don’t find myself tempted to go back and eat more peanut butter all by itself like I usually do. On the other hand, maybe that’s a good thing.

I had some extra ricotta cheese, left over from making lasagna, and I wondered: what else can you make from ricotta? Some googling turned up several answers, including Ricotta Gnocchi with Browned Butter and Sage, and I decided to try it out.

I’ve never made gnocchi, but I love eating it. I had some vague idea that it was generally made with potatoes. But this recipe creates mostly-ricotta gnocchi (with some parmesan cheese, parsley, and flour). The resulting dough was extremely sticky, even after adding some extra flour. But I rolled it out, cut it into little pillows, and then pressed them into a fork as directed. The next instruction was to drop them in boiling water and then spoon them out when they floated to the top, in 2-3 minutes. They were so squishy when I dunked them that I was skeptical that 2-3 minutes could really turn them into gnocchi, but sure enough, it worked! Very easy!

The browned butter with sage was absolutely divine. I was fascinated to observe that the butter really did turn from clear-ish yellow to a browned hue, simply by heating. Apparently this is caused by the milk solids and salt in the butter turning brown. Except that — ha! What I’d actually used was I Can’t Believe It’s Not Butter (I’m sure several of my friends are now cringing in horror). I don’t think it has any milk solids, but apparently, it browns too! And it’s tasty!

(Now I’m itching to look up the Fats chapter in my copy of “What Einstein Told His Cook”—I’m pretty sure this was covered—but I loaned it to a friend a while back.)

If you have any other great suggestions for ricotta cheese recipes, I’d love to hear them.

Last night, I spent a fun evening playing board games (new: Container!) and engaging in geek talk. Oh, how I love a good intellectual discussion! (You know, like the Salon des Geeks.) I guess it’s the geek version of a jam session; everyone hangs around and throws in their particular views or brings up new themes as the thought strikes them. Here’s what the idea buffet served up last night:

According to the latest evidence, Homo sapiens apparently did not evolve from Homo erectus. Both of us, plus Homo habilis, came from a common ancestor — erectus and habilis were different (less successful) offshoots.

There’s an anti-aging chemical that reverses effects such as a loss of elasticity in connective tissue which has been doing human studies since 2001 (and shown that it helps with, for example, hardening of arteries). However, the chemical’s patent expired, so it is now in the public domain, and no pharmaceutical company therefore is interested in finishing the (expensive) trials needed to get it FDA-certified.

I claimed that irradiated food seems to be unavailable because people are scared of the word “irradiated” and therefore wouldn’t buy it. Others noted that irradiated food can actually have a bad taste, since the irradiation process can damage the “good” proteins in, say, milk, not just the “bad” (bacterial) ones. So there might be a valid taste-reason that irradiated milk is inferior to un-irradiated (bacteria-laden) milk. Also, apparently many people agree with this statement: “If you had some radioactive milk, boiling it would make it safe to drink.”

As annoying as shopping is, it can be viewed in a more positive light if you think of it as an act of exercising your financial power. I like that.

And to follow up on my comment about carbonated fruit, there is actually a company, Fizzy Fruit, that is marketing it.

There was much more, and it got very late, and it was a great evening overall.

A friend pointed me to FreeRice, a site that donates 20 grains of rice to the UN for every vocabulary analogy you get right. Maybe the ETS (of SAT and GRE fame) should team up with these folks! In the meantime, you can study for your standardized exams and feel warm and fuzzy for your efforts. Or if you’re like me, you’ll get hungry and need to go fix yourself a bowl of rice.

Neat twist: The site doesn’t just run you through a gamut of random words; instead, it adapts to your progress by ratcheting up the difficulty until you start getting words wrong. As a result, I learned several new words today (it shows you the correct answer when you get them wrong):

captious: hypercritical (a lucky guess)

bunco: swindle (another lucky guess)

rodomontade: bluster (what, again?)

icteric: jaundiced (missed that one)

aperient: laxative (ugh!)

.. and so on. Go try it out yourself! Enjoy!