Joburg-based master baker Babette Kourelos of Babette’s Bread rises to the occasion and answers all our questions about making a starter (fresh home-made yeast)
By Babette Kourelos of Babette’s Bread
Photographs by Annalize Nel and Babette Kourelos
Q1. How do I make a sourdough starter and approximately how much starter is required for a standard-sized loaf?
A1. To make a standard-size loaf of bread, you will require between 50g and 100g of ripe and refreshed starter. You can make your own sourdough starter by mixing flour and water together and leaving the mixture to ferment. This mixture (which is a liquid starter and the most common type of starter – see A7 for the more on this) will require refreshing and feeding for the next 5 – 7 days (sometimes a little longer). The steps are as follows:
Day 1 In a glass jar, combine 50g white bread flour (preferably stone-ground and unbleached) with 50g/60ml lukewarm water. Add 1 tsp honey (optional) to give the wild yeast a little extra natural sugar to feed on and to encourage the yeast activity. Cover the mixture loosely with a lid/cloth and set aside in a warm place for 24 hours.
Day 2 Observe the starter and check for any signs of life (bubbles). Add a further 50g flour and 50g water, and mix well. Set aside again in a warm place for 24 hours.
Day 3 Observe the mixture and check for bubbles. Remove half of the mixture (100g) from the jar and discard it (or use in pancakes). Feed the remaining 100g with 50g flour and 50g/60ml water. Set aside in a warm place for 24 hours.
Day 4 – 7 Continue as per Day 3 and observe the development of the bubbles and yeast activity over a couple of days. It is quite common for a thin layer of watery liquid to appear on the surface of the culture. This is called “hooch” and is an indication that the starter is getting too “hungry” between feedings. Simply stir the hooch back into the mixture, discard half and continue with the feed as normal. From now on, you can feed the culture every 12 hours instead of 24 hours.
During the course of these 7 days (approximately), you should get a feel for and understanding of the culture’s unique schedule/cycle and feeding requirements. By making a mark on the glass container immediately after a feeding, you will be able to determine how quickly the starter doubles or triples in size after being fed. This can be anything between 2 and 8 hours after a feeding.
Once the starter is behaving predictably and consistently, and you know how quickly it rises (and how high it rises) before receding again, you can perform a float test. You can do this by gently placing a teaspoonful of starter in a glass of water. If there is sufficient yeast activity, the culture should float. (Note: If the starter is very runny, slightly reduce the amount of water in the next feeding).
Q2. What should the final result of my sourdough starter be?
A2. The healthy and mature starter should be bubbly and smell fragrant, fruity and yeasty. The size and prominence of the bubbles in the starter can differ from starter to starter and also depends on the hydration percentage of the starter. A healthy starter should double or even triple in size after a feeding.
Q3. If a recipe calls for instant yeast but I’m using a home-made starter/yeast instead, what is the substitution ratio of starter to instant yeast?
A3. As a general rule, 75 – 100g of ripe culture may be used instead of 5 – 10g of instant yeast in any given recipe. You will, however, need to subtract roughly 50g water and 50g flour from the original bread recipe to make allowance for the flour and water that is in the starter itself, eg. If the recipe calls for 500g flour and 350g/370ml water, you will use only 450g flour and 300g/330ml water plus the 100g starter.
You will also need to keep in mind that sourdough requires more time than instant yeast, eg. If the original recipe calls for 1 – 2 hours of rising time, you may have to allow for 5 – 10 hours of rising time when using sourdough. It is also important to note that sweet and/or enriched breads similarly require a longer rising time when using sourdough.
Q4. What are the most common problems that can arise while cultivating a starter and how do I fix them?
A4. The most common problem you might encounter when looking after your new sourdough culture is that it may develop a thin layer of watery liquid (called hooch) on the surface. The colour of the liquid may range from clear to yellow or even brown, depending on the type of flour you are using. This is quite normal and you can simply increase your feedings.
If, however, the starter starts to grow mould, it is better to discard it and start again. You could try to scrape off the mould and attempt to revive the uncontaminated starter underneath, but it is better to be safe than sorry and to simply start a new culture or get some from a friend or kind baker.
If, for some reason, your starter is not taking off at all and not becoming bubbly (even after a few days of regular feeding), it may be that the environment is too sterile. Avoid using harsh chemicals and/or cleaning materials in the starter’s immediate environment. (Remember we want to attract and encourage the wild yeast).
Q5. Can I freeze and defrost leftover starter and/or can I keep it in the fridge?
A5. You can easily freeze and defrost or even dehydrate your starter to preserve it for future use. To freeze, a liquid starter (as described in A1) can be placed in a resealable freezer-proof bag. A stiff-dough starter (as described in A7) must be tightly wrapped in cling film.
To dehydrate the starter, brush it on a sheet of baking paper and allowing it to dry. Once dry, you can break the dry starter into flakes and keep it in an airtight container. When storing the starter in the freezer or in dehydrated form, the starter will keep indefinitely. The starter will simply go dormant and will reawaken when soaked in water and fed with fresh flour. The starter may, however, require a few feedings before it bounces back to its usual vigour.
If you wish to keep your starter in the fridge, you can do this on a long-term basis, as follows:
- Bear in mind that if you are not baking regularly, you want to keep the starter as small as possible and only grow it when you know you are going to bake.
- Place your starter in the fridge in a glass jar covered with a lid/cling film to protect it from contamination or odours from other foods getting into it.
- You need to feed your starter once a week to keep it happy and healthy. Also remember that one always feeds a starter in accordance with the quantity of starter in the jar. For example, if you have a 100g starter, remove the jar from the fridge weekly and do the following: discard half of the starter and feed the remaining 50g starter with 25g flour and 25g/30ml water. Leave the newly fed starter on the kitchen counter for at least 1 hour before returning it to the fridge, as this will help to get the yeast going again before it slows down in the fridge – the cold slows down yeast activity.
- It is important to always keep a small amount of starter so you can feed it and grow it again for future use. Otherwise, you will have to start again and make a new starter from scratch.
To do this, remove the starter from the fridge, discard half of it (or a portion of your choice) and feed with fresh flour and water.
Q6. Can I make only sourdough bread with a sourdough starter?
A6. You can make any and all types of bread with a sourdough starter. Think normal sandwich breads to rustic and crusty artisan breads, as well as sweet and enriched breads like challah, babka and brioche. But the use of sourdough does not end there…
- The culture can also be added to many other recipes like homemade sourdough pasta, pancakes, pizza dough, crackers or flatbreads. You will even find wonderful chocolate brownies and Christmas cake recipes that call for the addition of sourdough starter. The addition of sourdough to any of these recipes will provide extra depth of flavour and nourishment to the old classics – just remember to make sure you convert your recipes to allow for the flour and water in the starter itself.
- It is important to note at this point that breads or baked goods made with a sourdough starter will not necessarily have a sour or acidic taste. The sour flavour will depend on how hungry/mature the starter is and how long the dough is fermented. A younger or less ripe starter will yield a milder flavour, whereas a hungrier or more mature starter will result in a loaf with a more pronounced, tangy flavour.
Q7. If I want to make 100% white bread or 100% wholewheat bread, do I simply use 100% of that type of flour in my starter instead of the combination of flours used in a sourdough starter?
A7. As per the answer in A6 above, it is not necessary to use a 100% white or 100% wholewheat starter. However, if you do wish to convert your starter so as to be able to bake a 100% white bread or 100% wholewheat loaf, you can start to feed your starter with the flour in question 2 to 3 times prior to baking with it. Alternatively, you can make a sponge using your starter and a portion of the flour that is required in the final recipe. Just remember to subtract the flour and water used in the sponge from the total amount of flour and water required in the recipe.
It is also important to note that sourdough starters can consist of 100% rye or 100% wholewheat or 100% white flour, or even a mix of any of these. The starters can also vary in terms of hydration. The most common sourdough starter is a liquid starter and it usually has a 100% hydration, which means that it has equal parts water and flour in it. The lesser-known starter is the stiff-dough starter, which is commonly used by the French and consists of 50 – 60% hydration (i.e. 100g flour to 50 – 60g/60 – 70ml water).
Q8. What about brown bread? What type of starter should I use for brown bread?
A8. Again, it is unnecessary to use only a brown bread flour starter in brown bread. If you are a purist and absolutely insist on having a 100% brown loaf, you can feed and/or convert your starter accordingly, but the amount of flour in the starter required to leaven bread is so small that you would not notice the difference.
Q9. And do I need a rye starter for rye bread?
A9. It is not necessary to have a rye starter in order to bake rye bread. As you progress and become more comfortable and proficient at sourdough baking, you may enjoy baking and playing with different types of starters and observing the subtle changes and differences these starters create in your usual or familiar bakes. But it is not necessary or advisable to complicate things when you are just starting out and still new to sourdough. It is, however, interesting to mention that rye does produce better bread when baked with a sourdough starter as opposed to being baked with instant yeast.
Q10. If I’d like to make just one starter for all my baking needs, what is the best all-round starter to make?
A10. The best and most reliable starter to make is a simple white starter (using white bread flour and water). You could also add 1 tsp pure honey or 1 tsp rye flour to the mix, just to give the wild yeast a little extra natural sugar to feed on and to encourage the yeast activity. This addition is, however, optional and only necessary when making the starter for the very first time. It is not necessary to add the honey or rye flour on subsequent feedings unless the starter is very sluggish and inactive. The white starter can easily be changed or converted to a rye or wholemeal starter or even a stiff-dough starter.
Q11. I’ve heard of a poolish – is it the same as a starter?
A11. A poolish is not the same as a starter but can be made using a bit of sourdough starter. When using a sourdough poolish, the poolish acts as the leaven which will allow the dough to rise. You may choose to make a poolish with your starter or you can simply add the amount of ripe and refreshed starter as called for in the recipe.
Q12. What would I use a poolish for?
A12. A poolish is a type of pre-ferment which was invented by Polish bakers in the 1800s and later adopted by French bakers. When making a poolish, a small amount of starter or instant yeast is added to a little bit of flour and water and left to ferment for a few hours or overnight. The poolish is a liquid pre-ferment, which differs from the Italian biga, which is a firm or stiff pre-ferment. The pre-ferment lends additional flavour and structure to the final loaf, as well as a richer colour in the crust. The pre-fermented dough is added to the final dough the following day, which is then allowed to undergo bulk fermentation, before being portioned, shaped and baked. A poolish made from your sourdough starter ensures the starter is sufficiently refreshed, healthy and ready to leaven a loaf of bread. A poolish made from a sourdough starter requires no additional yeast to be added to the final dough, whereas a poolish made with instant yeast will require a small amount of yeast to be added to the final dough.