Standard Pages (they don't change often)

Thursday, October 27, 2016

"Natural Yeast"

http://panemography.tumblr.com/post/149326234925/yeast-raised-banana-breadporn

So I was listening to the Good Food podcast on KCRW - a pretty well produced podcast, by the way - but it does tend to veer into the various wading pools of pseudoscience that pervades food enthusiast culture. On this particular episode, they were airing an interview with a bread baker, who proudly declares the the bread didn't contain any yeast, just a sour dough starter.

Now, I hear this a lot, as if commercial yeast were somehow inferior to wild "natural" yeast that the baker procured by chance. Some may even say it reflects the mystic "terroir" of the area. And in the same circles, "inferior" is often rounded down to "wrong". And such sourdough loaves can somehow be tolerated by the gluten intolerant (even though gluten is still there - it's again some kind of magical property that the mystic yeast imbues to the bread).

This kind of worship of the unknown somehow lends comfort to the hegemony of the kitchen. What industrially produced yeast has is predictability. We know exactly how long it will take to leaven the loaf, and it's been bred not to carry unexpected flavors. It does not obviate the inclusion of non-standardized microbial cultures, but certainly no reason to demonize the servile commercial yeast we can rely upon.

Thursday, May 12, 2016

Oliver Twisting



Multiple friends and acquaintances promptly sent this pretty good piece John Oliver did "exposing" the media exploitation of scientific studies. Whilst entertaining, the irony is that to do this piece, Oliver's team had to cherry pick the data itself. For example, how frequently did media outlets report the studies accurately as opposed to exploit it for the benefit of the story?

And let's not forget Oliver's own fast and loose interpretation of science (and "scientists") to forward the requisite controversy in a story.

Wednesday, May 11, 2016

Softer, whiter, more predictable

Selection of delicious doughnuts from Morningstar
On 10 May 2016, Houston welcomed the "next generation" of doughnut and coffee shop, Morningstar (probably best to follow the Instagram account - gorgeous). In covering the opening, HoustonPress mentioned that Morningstar uses "...unbromated and unbleached wheat flour (potassium bromate is often added to flour to create stronger, whiter dough, and is classified as a carcinogen




An interesting parenthetical clause. After all, much handwringing and high value is given to using "unbleached" and "unbromated" flour already exists, but what is the basis for mentioning potassium bromate directly?

Before we go into the chemistry of flour bleaching, I tried to find out just how often potassium bromate is added to flour. By law, it has to be listed among the ingredients, and it's quite difficult to source specifically bromated flour. In fact, I get the impression that using bromate in flour has fallen out of favor given the concern that less that fully cooked bread can retain trace amounts of it - and there are multiple alternative oxidizing agents available. I'd welcome comments as to the commonality of bromated flour in restaurant and home applications.

So why is bread bromated and or bleached? Freshly milled flour actually doesn't bake very well, and usually has a yellowish cast. Aging the flour while exposed to air results in oxidation of the proteins and carotenoids, resulting in a paler color, and better baking performance. However, aging is notoriously poorly reproducible, and slow. But we do know that what we are looking for is oxidation - so we can add oxidizing agents in trace amounts to not only speed the process but also make it more reproducible. So, bleaching agents (i.e., benzoyl peroxide) serve to whiten the flour, while maturing agents help develop the gluten. Potassium bromate is a maturing agent - so it doesn't serve to create "whiter dough". Note, however, that there are multiple possible bleaching and maturing agents. In most small batch situations, there really is negligible difference between using unbleached and bleached flour - arguably when scaled up to industrial levels, the differences in reproducibility can be dramatic. But at least in the case of cake flour, bleached (matured) flour is definitely superior in angel food cake

Search results for potassium bromate on Google will be dominated by multiple articles calling it out as a carcinogen - notably the IARC classification of carcinogen Category 2B. However, this classification is so broad, it includes things like coffee, pickled vegetables, and talcum powder. Being a powerful oxidizing agent, doses of potassium bromate is undoubtedly toxic, but I don't see any concern about it with regards to flour. Adding an emotionally charged and factually dubious clause to the report tends to fuel the misunderstandings about flour processing. I do think preference for unbleached flour is certainly any cook's prerogative, but scientifically, that declaration does not add significant value. 

Hat tip to Stella Parks of bravetart.com for her article in Serious Eats. And to Sam Vance (@samvance on Twitter) for vigilant reading of food science, and for sending Stella's article my way. 

Tuesday, November 3, 2015

Ghost of Gluten-free

Torta de chile relleno. Oaxaca, Mexico. 

Or "How modern journalism works".

Keeping up with the scientific reports, I came across this link suggested by a popular science communication site. Dated 2 November 2015, it's a snarky blog post titled Millennials Seek New Ailment After Gluten Sensitivity Turns Out Not To Be Real - the gist of which is summarized in the first paragraph:
A new scientific study by the people who proved that gluten sensitivity is a definitely a thing has proved that gluten sensitivity is definitely not a thing.
Note the use of "new". Following the link, it leads to a ScieceAlert page dated 19 August 2015, which details a familiar shift of the issue from gluten to FODMAPs. Reaching the end of the article, we note that this was actually originally published in Business Insider on 16 May 2014. Which means that the journal article being cited as being published "last year" was relative to that date - indeed, it actually refers to the Gastroenterology paper published in Aug 2013.

So, like what was old is new again, thanks to the remix nature of internet reporting. Back then, the iPhone 5 was the hottest thing around.

Thursday, October 29, 2015

The physics of frugal fluffiness

Hokkaido cupcake, Kamalan Bakery, Houston, TX

I've recently become fascinated by Hokkaido cupcakes (sometimes just Hokkaido cakes). The only purveyor I know of is the recently opened Kamalan Bakery in the ever expanding new Chinatown region of Bellaire in Houston. Based on my research, despite the name, the cake didn't originate in Japan, but rather in the ethnic Chinese enclaves of Singapore and Malaysia. It's a product of leveraging physics and frugality to accomplish a delicious product. At its core, the cupcake is a chiffon cake - a close relative to the angel food cake - the latter is basically a prime example of a physically leavened cake. Rather than using chemical leaveners such as baking soda, an angel food cake relies on a lot of egg whites beaten into a semi-stable foam to produce it's airy structure (some manufacturers may cheat, however, and use the foaming qualities of detergent to accomplish the same thing without less labor). In the chiffon cake, the egg yolks are not discarded, but used to emulsify and incorporate additional flavoring ingredients. At its most basic, that could just be some milk and oil, but any number of flavoring components can be used. Flour is then added, but at a smaller ratio since the gluten formed toughens the cake. The beaten egg white is folded in last just before baking to produce a fluffy cake much prized for its texture.

In a sense, a chiffon cake is basically a stabilized soufflé.

Due to the delicate nature of the foam, it needs to cling to the edges of the pan to promote rising, thus, chiffon cake containers cannot be lubricated for ease in unmolding, and the cake must be cooled upside down to avoid collapsing.  When baked in a flute pan with a central chimney, this is possible, but as a cupcake, cooling upside down is impractical. But the ever frugal inventors came up with a clever solution: reinflate the cake with filling:


A Hokkaido cupcake puts the Twinkie to shame with filling abundance. It can be filled with any number of fillings, from custard to basic whipped cream, flavored or unflavored, which serves not only to provide flavor contrast, but also provide basic structural properties to the cake. Numerous recipes and videos can be found online, though most will be Southeast Asian in tenor.

Note also the use of square cardboard cupcake liners. These are quite clever - the traditional fluted liner is there to facilitate removal from the pan due to the no-grease requirement, but still requires a traditional cupcake pan mold. The cardboard cups provide sufficient strength on their own to be used without the pan mold, and the square shape allow for more efficient use of oven space. However, they seem to be rather difficult to find in American groceries.