Logic-free thinking

I just found out that there are a lot of people who believe sourdough is yeast-free, and plenty of organisations and companies that encourage that belief by people who for whatever reason want to follow a yeast-free diet.

True sourdough bread does not contain yeast and instead utilizes a lactobacilli based starter culture.[1]  True sourdough bread is also baked at a lower temperature[2] for a longer period of time which protects the integrity of the cereal grains[3] and preserves the nutritional value[4].

[1] No. It’s lactobacilli and a variety of yeasts living in symbiosis, where the bacteria consume sugars in the flour the yeast cannot and the yeast consumes the fermentation byproducts of the bacteria. Lactic acid produced by the bacteria lends the sour flavour; the yeast produces the carbon dioxide that leavens the bread.
[2] Generally speaking, it’s baked at the same or just slightly lower temperature than other breads but indeed for a longer time because the crust browns more slowly.
[3] Integrity of the grains? Come now, they’ve been powdered.
[4] For any reason other than it sounds appealing?

Yesterday, I found that a local bakery that produces a decent sourdough – I’m partial to their sourdough rye – also fails to understand some basics:

The natural yeast itself also has important health benefits for your digestive tract (the good bacteria[1] survive in the center of the loaves where the internal temperature does not get hot[2]).

[1] Yeast is good, but it’s not a bacteria; it’s a fungus.
[2] The good bacteria do not survive. Lactobacillus sanfranciscensis is killed after just a few minutes at 140°F/60°C, and the centre of a sourdough loaf – most breads, for that matter – should reach around 200°F/95°C for a few minutes before it’s taken out of the oven. Take it out before that and the middle of the loaf will remain unset and gummy. Their loaves are not unset and gummy in the middle.


Current temperature 140.1F

Edited to correct first link.

Sour and sweet


I haven’t made sourdough in quite a while, so I started re-energising my starter Thursday night and finally baked this boule today. I love returning to sourdough because it’s always quite pleasant, even a bit of a rush, to find that I haven’t lost my touch – or my starter, for that matter.

It’s been about ten years now since my boss – two bosses ago, that is – brought me a pint of live dough from a San Francisco bakery on his return from a California trip. It’s hardy stuff. It survived its initial mistreatment in the cold baggage hold of an airliner, where it burst its plastic container but was held by the first of two layers of freezer bags, and seems to laugh off my periodic neglect, when I’ve forgotten the starter’s in the back of the fridge and didn’t feed it for a month. Or two. Or…well, never you mind how many months it was that one year. As you can see, Lactobacillus sanfranciscensis and Candida humilis have both forgiven me, and that’s all that really matters. We three get along just fine.

Keeping a sourdough starter alive for ten years is pretty good, but it’s just a couple of ticks compared to some. King Arthur Flour sells a sourdough starter of a New England variety with a lineage back to the mid-1700s. I used their starter before I got my San Francisco nugget of gold. The San Francisco variant has a tangier taste and produces a slightly creamy texture that adds another element to the crunchy crust and chewy crumb. I’ve found the San Francisco sourdough is slightly less active than the New England variant, which adds time to the feeding and proofing cycles, but it’s worth the wait. As I am sometimes wont to say when pressed, “I can do it quickly or I can do it right. Which would you prefer?”