Sourdough work in progress (part I)

Attempt to make a sourdough starter using dried apricots, using my immersion circulator for temperature control. I got some bubbling yeast activity, but the final bread dough never rose properly.

Inspired by the Swedish bread blog Pain de Martin which I recently discovered I decided it was time to have a go at sourdough breads! Although one of my favorite types of bread it’s a long time since I gave it a try and even longer since I actually succeeded. Leaving apple peel covered with water for two weeks in a cool place (15 °C) I got a light apple cider which I used to make a starter some years ago. I followed a recipe from the Norwegian artisan bakery í…pent bakeri and it gave a marvelous bread. But since then I’ve tried to repeat this twice without success. No wonder that even Rose Levy Beranbaum in her book “The Bread Bible” writes that she didn’t intend to include a chapter on sourdough at all. There’s no doubt that sourdoughs are tricky, but I was a litte surprised and disappointed that someone who sets of to write a 600+ page book on bread even considered to skip sourdough… Luckily she changed her mind and the introduction has a fascinating nice-to-know fact: 1 g flour contains about 320 lactic acid bacteria and 13000 yeast cells!

I believe one the reasons why sourdoughs seem to live their own lifes sometimes is that they need to be kept in a warm place. My kitchen isn’t that warm so I figured it was time to use my immersion circulator and give sourdough another chance (who says you can only use immersion circulators for sous vide anyway? – I think my next project will be to make yoghurt!). With a thermostated water bath keeping a sourdough starter at constant temperature is as easy as 1-2-3. But surprisingly I haven’t seen any blogposts yet from people using their sous vide water baths for sourdough starters (although some have built their own water baths for this purpose using aquarium equipment).

Fresh apple peel in water. This particular experiment failed – the cider smelled OK, but there was quite a lot of mould on the surface after two weeks so I didn’t dare to proceed …

It was Martin’s post on an apricot starter that triggered my desire for sourdough (but careful – never close your jar with a rubber as shown in his picture!). I got a bag of dried apricots and gave it a try. There was some bubbling and it smelled quite nice, but the bread dough never rose properly. I later found out that in a comment to the first post and a later post on the same topic it was pointed out that the apricots should not be treated with sulfur dioxide or a sulfite (used to conserve the fruit, appears on labels as E220-228 in Europe). That’s very obvious once you think about it, because the sulfur dioxide/sulfite is there to kill microogranisms and increase shelf life. For a sourdough however you want living microorganisms! The solution to this is to use untreated dried apricots. I haven’t been able to find any yet, but I’ll definitely give it a new try once I find some! Other options of course are to use dried or fresh apples, pears, grapes – preferably not treated with pesticides or sulfur dioxide – as the surface of these fruits are host to many yeasts.

A relatively firm rye starter with 150 g water and 200 g whole grain rye flour (left) shows signs of yeast activity after 24h at 28 °C (right).

Having failed with the apricot starter I decided to give a traditional rye sourdough a try, using a recipe from the book “Brød” (=bread) by “í…pent bakeri”. I got a nice bubbling after 1 day, but the starter was pretty dry. As I discarded a portion and fed more flour and water to the starter it seemd as if it died… I (believe) I followed the recipe very accurately (except for the very first day where I opted for a hydration of 75% instead of 60%), but the final dough never rose, so I had to cheat and add bakers yeast in order to actually get the breads baked. Acid production was fine however and the resulting flavor was very delicious and I got the crumb that I desired! However, with all these problems I figured it was time to turn to the scientific litterature and read more on sourdouhs … More on what I found out in a follow up post.

One last thing: Despite my limited experience with sourdoughs I’ve already been a little annoyed by recipes for starters that require one to discard a significant portion of the sourdough every day before feeding the start with more water and flour. One obvious way around would be to start at a much smaller scale so that every feeding can be done without having to waste any sourdough. In fact Kurt Janz already has a post with detailed instructions on a less wasteful sourdough (and he BTW has one of the most comprehensive sites on sourdough I’m aware of including a sourdough calculator). The only reason I could think of why one perhaps would want to use more than a couple grams of flour to start with would be to outnumber any unwanted yeasts or bacteria from the air or the equipment. Is this the case? Are there any other reasons? To circumvent this one would simple have to work very clean and wash all equipment properly.


  1. I’m wondering why you are bothering with all the fruit and the immersion circulator etc. I have two starters – one is rye, the other is wheat, both were made over a number of days with flour and water left covered in a warm place and nothing else and both work very, very well, are very active and I get a very good rise on my bread. In fact, the rise on my wheat bread is often so good you would almost suppose it to be made with baker’s yeast. I followed the instructions found in Andrew Whitley’s Bread Matters and never had a problem. His tend to be quite wet and develop quite quickly. You don’t have to discard any of the mixture during the process of making the starter, and if you have too much at the end, there are a variety of other uses for it. Failing that, you can always freeze some in case something happens to your working one….

    • As I mentioned I’ve had a very good experience with the apple cider – it imparted a very nice flavor to the finished bread. What I hope to achieve using an immersion circulator is a more robust procedure. For instance you mention that you leave your starter in a “warm place” – is that 20, 25 or even 28 °C? I’ve also seen reports that the temperature used can influence the lactic acid/acetic acid ratio as yeast and bacteria have different temperature preferences. But maybe my approach is a total overkill? Since you’ve never had a problem with your sourdoughs – what ratio of flour to water do you use for your starters? How often do aerate them? And how often do you feed them?

  2. IMHO….

    Catching wild yeast like that is like walking into your back yard and grabbing any old greenery to see if it tastes good.

    I’m sure you know that your culture will become more active with frequent use.

    I think you should buy the Italian cultures from The book available there is also pretty good, Ed Wood is a medical doctor and a scientist.

    The water content of your starter isn’t all that critical, however it is a lot easier to judge its activity level if its very stiff. The most important thing of all is to feed them often and use them when they very active (double in 2 hours).

    I don’t think your temperature control is overkill, although I would suggest that if you have a PID lying around, you might find it a lot easier to use a light globe and a cardboard box.

  3. If you’re looking for unsulphured apricots, most health food stores will have them in their bulk bins. If your local health food store doesn’t carry them, try Wholefoods.


  4. interesting topic. For questions on hands-on matters, I can recommend a chat with Jonas (theoretical physics/chemistry) over at The cod liver paté ( He has done quite a lot on bread, all aspects I think. Also, an interesting video of Peter Reinhardt at the food geek (

  5. I did a sourdough starter experiment in the fall, but alas, my kitchen was too cold (and I didn’t use a whole grain flour) and it died off. However, the first few days were promising–I used fresh pineapple puree. I’m waiting until the weather warms up just a little bit more to try again. Soon. Very soon.

    Love the use of the sous-vide process. And the link to the acquarium. Brilliant!

  6. I’d like to reinforce Catherine’s position above. I’ve been studying bread baking intensively in the last two months through books and experimentation. There are a number of pre-ferments to consider. I’ve played with the poolish/sponge type as well as the rudimentary levain and was just setting out to develop a sourdough culture. I had read this post earlier and felt it was a little of an over-reach, rewarding as study but maybe geared improperly.

    This week I received the best book to date I think on bread baking knowledge and technique. It’s by Daniel DiMuzio – ‘bread baking’. His style, coverage, depth and pedagogy suggests this is going to be a classic.

    His suggestion on selecting sources of yeast and bacteria is to stick to a flour mix that is high in bran (for the source) and has naturally ferment-able sugars.

    His reason for avoiding other sources is that the yeasts in those sources never end up being the surviving cultures anyway. The exotic yeasts don’t have the staying power or profile required for bread baking. The development period of sourdough preferment essentially eliminates those not sourced from flours.

    Catherine’s use of wholewheat and rye is the right choice. And ‘Bread Matters’ is another superb book already a classic. Both books are complements. Other books are also superb and I would recommend many but this one leaves much of the philosophy speak out yet pays homage respectfully and concisely.

    Love your efforts and your blog, gnm

  7. If you have excess sourdough, you can make sourdough pancakes! Today I made them like this:

    250 ml of sourdough, nice and acidic
    1 egg
    1 spoon of corn oil
    2 spoons of sugar
    pinch of salt
    (optionally) pinch of baking powder

    mix just before use, cook in hot pan or griddle like regular pancakes. If it is too acidic, add milk and flour. But these pancakes recipes are really non-critical…

    Anyway, the characteristic sourdough flavor survives cooking. Eat with butter and jam or syrup.

    • Walter: That’s a good idea – in fact I also have a plan to make injera soon! I’ve made pancakes with yeast several times, often also using kefir/soured milk – so I can imagine that pancakes with sour dough would be delicious! Just a few questions: what is the hydration of the “sourdough” you use? Do you use a 1:1 ratio of water to flour? I also reckon that you use what flour (or at least not only rye)?

  8. My sourdough starter (culture? pet? symbiosis? you decide!) is based on a cup of starter that a friend of mine recently gave me. She uses a 1:1 flour to water ratio, and who am I to question her wisdom? So I persist with 1:1. And yes, it is wheat flour.

    Compared to regular pancakes, the surface is a bit different. Difficult to describe, but I would say a bit more crusty. I have also see recipes where more wheat flour is added.

    I would also like to take the opportunity to thank you for the work on this site. It is a great resource, I have used your recipes more than once and I point my students to it.

  9. If your looking for good apricots without the sulfur, try Newmans Own Organic Apricots. They are California Apricots that have been Retorted after drying and washing. The color will be that of an undesireable brown, but will serve your needs well for sourdough.

  10. Martin,
    A few things to consider:
    Water – Chlorination, particularly the more recently introduced bromine compound [this cannot be boiled or evaporated off as the earlier chlorine form could], will greatly suppress sourdough activity. I learned this the hard way, very frustrating.

    Flour – I have found unbleached, stone ground [less heat during milling] wheat to be better than bleached. The stone ground whole wheat becomes active somewhat faster than white flour in my experience; I assume the bran preserves the stowaway yeast more effectively.

    Yogurt – I now use a method developed about thirty years ago by the Sunset Magazine kitchens using a few tablespoons of plain yogurt [my scientific selection of brand involves reading the ingredients label and choosing the one with the greatest number of different strains of lactobacilli] mixed with your chosen flour and sufficient milk to form a batter [thick or thin as you choose]. Initial temperatures ranging from 70 F to 90 F are ideal [I have found switching on my incandescent oven light will raise the temperature of my electric oven to ~80 – 85 F — do not turn the oven on –]. Once active, the sourdough starter is thereafter maintained with flour and fresh milk [avoiding any chlorine issues; dry milk will work, but then distilled water is required], and stored in the refrigerator during periods of infrequent use. Sunset Magazine goes into considerably greater detail in at least two magazine articles published over the years [these were also reprinted in at least one of their annual recipe books]. You may also be able to find something on their website [].

    I find this starter to be extremely stable and robust. Whichever strains can live in harsher more acidic environs win out; I just let the little beasties work out their own modus vivendi, and the CO2 layer is proof against any air-breathing intruders.


  11. Hope You can traslate this
    E’ detto anche lievito acido, o pasta madre, o pasta acida. per la produzione di lievito naturale. Il lievito prodotto con questo metodo ha la consistenza di una pastella.
    Tempo di preparazione e cottura: 10 min pií¹ 3-5 giorni per la fermentazione
    Ingredienti 10 acini di uva passa250 ml di acqua150 g farina (meglio se integrale)
    In una ciotolina mettere l’uva passa e l’acqua e lasciarla cosí¬ per 3 giorni. Lasciarla scoperta e al riparo dalle correnti d’aria.
    Trascorsi tre giorni, l’acqua sarí  diventata torbida e giallina con una patina in superficie.
    Filtrarla, prelevarne circa 150 g e versarla in un barattolo piuttosto grande e aggiungere la farina.
    Mescolare bene e coprire parzialmente con un coperchio (in modo che l’aria possa entrare), e mettere il contenitore in luogo riparato. Entro 48 ore (o prima, a seconda della temperatura ambiente) il composto si gonfierí  riempiendosi di bolle.
    Questo í¨ segno che il lievito “í¨ nato”!A questo punto si puí² cominciare ad usare.
    Il lievito va conservato nel barattolo, parzialmente coperto, a temperatura ambiente e “rinfrescato” ogni due giorni. Si consiglia di conservarne una quantití  pari a circa 100-150 grammi.
    Per i primi 3-4 giorni si consiglia, partendo da una quantití  di lievito pari a circa 150 g, di rinfrescarlo con 100 g di acqua e 100 g di farina
    Le operazioni di rinfresco.

    Travasare il lievito in un barattolo pulito ed aggiungere acqua e farina in pari quantití . In particolare:

    Rinfresco per produrre il pane: per 500 g di farina occorrono 150 g di lievito attivo.
    Quindi aggiungere al lievito 75 g di acqua e 75 g di farina e mescolare bene. In un paio d’ore il volume del lievito raddoppierí  (a temperatura di circa 26 gradi). Prelevare i 150 g necessari per il pane e conservare il resto.

    Rinfresco per conservare: aggiungere 20-30 g di farina e la stessa quantití  di acqua. Mescolare e conservare.

    Regola fondamentale
    Quando si decide di intraprendere l’avventura lievito naturale, non bisogna avere fretta!!!
    E’ necessaria molta cura e molta pazienza.
    Se il lievito non appare abbastanza “vispo” non decretarne subito la “morte”, ma provare a ridargli forza mediante diversi rinfreschi successivi, finché non raddoppia di volume in 2-3 ore.

  12. @Dennis:

    a) Chorinated (or chloraminated) water isn’t necessarily a problem. I feed my starter on tap water and it triples in eight hours when fed.

    b) Yeast *is* an “air-breathing intruder”. 🙂

    As for methods, I really find all this complication baffling. I’ve twice used a straight water/flour method documented here:

    Both times, I’ve cultured extremely successful starters with this method, the first time in about nine days, and the second time in just five. All this business with fruit, yogurt, and so forth is, at least in my experience, completely unnecessary. Plain whole wheat flour, whole rye flour, and water will yield a perfectly serviceable starter (which you can then feed with the same ingredients). All it takes is patience and a little care.

  13. Thanks for all the tips! One thing I’m thinking about in particular now is that yeast requires oxygen to multiply and grow whereas the lactic acid producing bacteria do not. So if left alone unstirred there’ll be plenty of sourness, but not much bubbling activity. This suggests to me that one needs to stir sour dough vigoursly to help the yeast multiply.

  14. Two things that worked for me (learned the hard way):

    – Temperature control is everything: I now use an Auber that I normally use for sous-vide, just with different settings and a lightbulb in my baking oven. I use this setup for both the refreshening of the starter (ca. 8 hours or whenever I get to it, no stirring necessary) and the spring of the bread (1-4 hours). I keep the temperature at 29 C.
    (Sourdough temp control was actually the selling point for the Auber as opposed to an immersion bath (well, together with the price tag…))

    – I started the thing from wheat and water, nothing else. The “older” (more generations), the better it gets. Simple as that, no need for measures like grapes, apricots, or anything else.

    Personal opinion from here on: Buying a starter might be good to get you going right away, without the patience necessary to start your own and go trough a couple of generations. But later on, as you are not working in a clean room, wild yeast from the area where you do your work will start to get into your starter. They might be suppressed by the present population or take your starter over or something in between might happen. Basic point is, you will never know anyway…

  15. Martin,

    My experience is that what you are trying to do when you make a sourdough starter is simply create a little mini-ecology that exactly suits you, your kitchen, your flour, etc. Learn the whole process at room temperature. Don’t worry about throwing away flour until you understand the process–when you understand the process then you can optimize it, and if you bake bread daily, you will not throw away anything. Keep the starter in a transparent or translucent semi-cylyndrical cup that is twice as big as how much starter you have so you can see at a glance the timing of its activity. Make the starter be 80% hydration so it is more like a dough. Always refeed every 24 hours without fail. Your new little mini-ecology will stabilize in only a week or so, and when you see it rise you will be assured of its leavening power.

  16. Hi,
    Just wanted to let you know if you did not already find some unsulfured dried apricots. That I purchased this brand;
    “Good Sense” company.

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