How to make San Francisco sourdough bread

San Francisco sourdough bread is considered by many as the holy grail. Many bread makers have spent countless hours of their lives learning how to make San Francisco sourdough bread and I now consider myself one of those bakers. My journey with this style of bread began many years ago. It was initially met with hours of frustration and disappointment. After many failed experiments, I finally discovered a consistent method of baking the bread I was searching for and it has become a staple in my kitchen ever since. I am going to share with you my method of baking the elusive San Francisco sourdough bread.

San Francisco sourdough bread may not be to everyone’s tastes. It’s tangy, almost vinegar-like flavour is either loved or hated. One thing is certain, once you fall in love with its flavour, eating any other type bread just leaves you feeling incomplete. For those of us who have devoted days preparing the dough, the satisfaction of finally cutting into a slice somehow makes the lengthy process of making it seem more than worthwhile.

Making your bread really sour using whole grain flours such as wholemeal and rye is a fairly simple affair. The more acidic sourdough bacteria seem to favour whole grains when it comes to bread making. However, obtaining really sour bread using a white flour is a much more difficult thing to achieve. I have literally spent years perfecting this method of baking sourdough bread. I used to think it involved some really advanced techniques that only seasoned bakers had mastered. I know today that it’s more a matter of patience rather than a matter of skill.

What’s required to achieve San Francisco sourdough bread?

In order to make this style of bread, you must have the following: A levian prepared with a mature starter, a very high protein flour with lots of gluten and a way to keep the dough warm at a consistent temperature. I will discuss each in more detail below.

The process from start to finish for this bread will span over 3 days. It might sound like a ridiculous amount of time to devote to a loaf of bread, but the task is fairly effortless and the dough is left unattended for the majority of the process.

Before attempting to learn how to bake San Francisco sourdough bread, we would suggest that you are already familiar with some of the basic techniques and terminology discussed below. You can gain that knowledge by reading our really easy no-knead Dutch oven sourdough article [click here].

THE LEVIAN

The levian should be prepared from a mature starter that has been well fed and kept warm for several days. The yeast responsible for most of the sour tones in this bread come from L. sanfranciscensis. Although it is likely any starter will contain some of this wonderful yeast already, we use our San Francisco sourdough starter which is already very high in this naturally found, heat-loving yeast. We keep our starter fed once a day for a few days leading up to the day we plan to make up the dough for this bread. Keeping the starter warm is crucial. Ideally around 25c. This will increase the amount of L. sanfranciscensis greatly. The final feed of the starter happens the evening before we start the levian.

We build a 100% hydration starter the morning of the day the dough is to be made. We only need a small amount of levian, so we use just 5g of starter with 5g of strong white bread flour and 5g of water. The levian will be left to rise for at least 6 hours. It will smell tart and vinegary and have risen well before we use it.

We will only be using a very small amount of levian in our bread. Just using 10g of levian might seem strange. However, the more levian you use, the faster the bulk fermentation will happen, and for this style of bread, we want a really slow bulk fermentation so we only use a very small amount of levian.

THE DOUGH

The fermentation of the dough for this bread is 48 hours. It is a two-stage process where we firstly bulk ferment the dough for 24 hours and then prove the dough in the fridge for a further 24 hours.

The flour used to make the dough must be high in both protein and gluten. This was for many years the missing part of the puzzle in this method for me. Most strong bread flours contain about 12% protein and moderate amounts of gluten. Sadly, it takes a very special flour to be able to withstand a 48 hour fermentation process. The protein content should be around 14% and it should contain enough gluten to be considered “very strong flour”.

Personally, I favour Canadian white flour for this task, albeit not always organic, it has proven itself time and time again as the best flour to use for San Francisco bread baking. Below is a list of flours I have tested and can confirm work for the job at hand. These are all available in the UK, either in supermarkets or online.

TEMPERATURE

Consistent temperature is also another important factor in making this bread. I have found a bulk fermentation of the dough at 24c for a full 24 hours gives the best results. Although you can experiment with warmer temperatures, I have found that it often leads to the gluten breaking down resulting in baking disasters. 24c for 24 hours in my experience gives the best results.

The obvious issue is that it is very difficult to maintain dough at a consistent temperature without specialist equipment. Personally I use a dedicated bread proofing device to achieve this. I use a Brod and Taylor bread proofer which costs around £150. It allows me to heat dough to a specific temperature for any amount of time. Sadly, it will not cool the dough if the room temperature is already above that specified. That means that warm periods of the UK summer, I’m simply unable to bake this bread using this method.

If you want consistent results with this style of bread, I can’t recommend enough using a bread proofing device. However, I totally understand that most people would not want to spend that kind of money on a piece of equipment! So where does that leave you? Well, you still have some options. You can try leaving the bread in a warm spot in your house. As long as the temperature does not go over 24c, you can still achieve decent results. I have stumbled across a few bakers over the years that do not own a bread proofer and still bake some fantastic San Francisco bread. The key is being able to monitor the dough temperature. The best way to do so is by using a thermometer designed for food such as this one.

HYDRATION

Although it is possible to bake this style of bread at high hydration, I would suggest starting off with a fairly low hydration dough to get a feel for working with such a long fermentation time. High hydration bread that has been bulk fermented for 24 hours can be very difficult to work with.

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THE RECIPE

Ingredients:

600g High protein strong white flour
420g Cold water
10g Levian (100% hydration)
12g Salt

Add the starter to the water and stir well. Combine the salt, flour and water/starter mixture until a rough dough has formed. This can be done by hand or by using a dough mixer. Put the dough into a suitable container. I use a food-safe plastic tub with a lid.

Please note that we do not perform an autolyse on this dough.

If you are using a bread proofer, set it to 24c. I do not fully seal the lid on the tub. Doing so can cause the dough temperature to increase further, causing issues. The proofer should have a method of keeping the dough from drying out. For example, mine has a small water tray.

If you are not using a bread proofer. Seal the lid and leave the dough somewhere warm.

During the 24 hour fermentation stage, check on the dough on a regular basis. If possible, every 6-8 hours. You will often find the dough has risen greatly. Punch the air out of the dough and perform a series of stretch and folds when you notice this has happened.

With a long fermentation like this, regular stretch and folds are not as essential to perform as gluten strands develop naturally over this long period of time.

After 24 hours have passed. Shape the dough and place it into a banneton or other suitable proofing container and place it in the fridge to retard for a further 24 hours.

Tip: if the dough is hard to shape warm, place it in the fridge to cool for a few hours and then shape it, returning it to the fridge again after.

Bake the dough cold, straight from the fridge in a dutch oven (or similar) on the highest possible oven heat the dutch oven can handle with the lid on for 35 minutes. Remove the lid and cook for a further 25 minutes allowing the bread to brown. My own oven only reaches 230c and these timings are based on that temperature and may need adjusting for your own oven.

Once cooked, allow the dough to cool on a cooling rack or similar. Leave the bread to cool for at least 24 hours before slicing. This part is important. The sour flavours in the bread need time to develop. Cutting the bread too early means you are likely to lose some of that sourness.

You have now gained the experience required to learn how to bake San Francisco sourdough bread. As with any sourdough recipe, nothing is set in stone. Fermentation times and temperatures may vary depending on many variables such as flour, water temperature and the activity of your starter. Please experiment and modify this recipe until you achieve the bread you desire.

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