How to Bake a Perfect Sourdough Loaf – Secrets to Sourdough Baking I Learnt on My Quest

How to bake a perfect sourdough loaf is something I’ve been thinking about a lot recently: what is my idea of a perfect sourdough loaf. Well, I’ve finally been baking it, many bakes in a row, week after week. I want to share my quest for the perfect sourdough loaf and perfect sourdough crumb, and some secrets to sourdough bread baking I’ve learnt so you can bake your perfect sourdough.

As regular readers know, I’m an avid sourdough baker, feeding my starter daily and pulling sourdough loaves out of the oven every three or four days – which is how I found myself pondering what my idea of a perfect loaf of sourdough is and how to bake a perfect sourdough loaf.

Successful sourdough baking has a million variables – let me state that right up front: types of flour, types of starter, hydration levels, bulk fermentation times and interactions (like folding), scoring, baking temperature, room temperature, water temperature, vessels used to bake the bread with, oven types… the list goes on forever.

Because I’ve been baking sourdough bread for nearly five years (and I’ve been baking for over 30 years in some capacity), I have probably seen it all in terms of results. Dense flat loaves. Dense flat loaves with strange ‘tunnels’ through them. Slightly less dense loaves with holes on one side or just the top of the loaf… that’s a long list, too.

Despite the encouragement of my wife – “we can make Tuscan bread soup with this one…” she assures me, and “this will be great for panzanella!” – these failures can be disheartening. But it’s important not to give up. The rewards of sourdough baking are wonderful.

If you’re new to baking sourdough, see my ultimate guide to sourdough baking, which includes everything from a beginners guide to baking sourdough and simple sourdough starter guide guide to my list of essential sourdough tools to get you started and plenty of sourdough starter discard recipes. 

If you’ve been baking sourdough for a while and are asking yourself the same kind of questions that I’ve been asking of myself, then here’s my guide to how to bake a perfect sourdough loaf and some essential tips to sourdough baking that I learnt on my quest for my perfect loaf of sourdough and achieving my idea of a perfect sourdough crumb.

But before I share my tips, can we ask a favour: Grantourismo is funded by its readers. If you’ve enjoyed my sourdough guides and recipes or any of our recipes, please consider supporting Grantourismo by using our links to book accommodation, rent a car or campervan or motorhome, buy travel insurance, or book a tour on Klook or Get Your Guide.

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How to Bake a Perfect Sourdough Loaf – Secrets to Sourdough Baking I Learnt on My Quest

A guide to how to bake a perfect sourdough loaf and essential tips to sourdough baking so you can bake your perfect loaf of sourdough and perfect sourdough crumb again and again and again.

The Key to Baking a Perfect Sourdough Loaf

The key to baking a perfect sourdough loaf and baking consistent sourdough loaves of bread to your taste is a task, first and foremost, of reducing the variables. It is only after you have narrowed down the things that can go potentially wrong with producing a consistent loaf or consistent loaves that you can fine-tune your bread-making to achieve your desirable results.

One of the rewards of narrowing down the variables to creating a consistently good loaf is that your bread is always edible. The end product might be a little flat from under-fermenting or over-fermenting the dough. It might have a tight structure or be full of odd big holes and it might not have a great ‘ear’ (the part of the loaf that rises up from where you’ve scored the dough). But it will be edible, hopefully enjoyable, and make some great toast, croutons or breadcrumbs – at least that’s what my wife says!

How Do I Know That I’ve Made a Great Sourdough Loaf?

First up, don’t let anyone discourage you on your quest to baking your perfect sourdough loaf with your idea of a perfect sourdough crumb. There are a lot of sourdough bread nerds out there. If you proudly put up a photo on social media of a ‘good’ loaf you’ve made, you’ll soon be told why it’s most certainly not a good loaf. Social media can be a cruel place.

Having said that, there are objective factors to telling whether a loaf of bread is well fermented and baked. Your own personal preference for how you like your bread to look, feel and taste is an extension of creating a well fermented and baked loaf.

If you’ve ever wondered why professional bakers take a fresh sourdough loaf from the oven and cut it in half (don’t do this at home, the loaf is still baking and firming up) is that they’re looking at the sourdough crumb.

A baker’s sourdough crumb is not the same as your idea of a crumb or crumbs. It’s not those little pieces of crust that fly away as you cut into a bread loaf or that box of breadcrumbs that’s been sitting at the back of the cupboard that you cannot remember what you bought it for, it’s the internal structure of the loaf. Cutting the loaf in half gives a baker a good indication as to how well the loaf was fermented, proofed and baked.

Factors to Consider in Reading a Sourdough Crumb

There are three main factors to consider when reading or judging a sourdough crumb. If you’re currently making sourdough bread that has some structure, some holes, and tastes good, that’s fine, you’re doing great! But reading the crumb is the best way to move forward to creating your perfect loaf.

The first factor is the loaf height and shape. The best loaves are tall and rounded, with high shoulders and a noticeable ear. The ear is at the top edge of where you scored the loaf. Note that it’s best to do a simple single score of the loaf – whether it’s a boule or a bâtard – while you’re still trying to perfect your loaf.

If your loaf unfortunately has the profile of a frisbee, it could be under- or over-proofed. We need to consider this second factor to determine which category your loaf falls under. Let’s examine that sad frisbee to see what happened.

So the second factor requires looking at the holes in your bread. If the holes are tightly structured at the bottom of the loaf and large at the top, that typically means it is an under-proofed loaf.

If your loaf has random large holes and some are separating the crust from the bread, that’s an indication that the bread is over-proofed.

If you have a tall and rounded loaf with holes of all sizes evenly distributed across the loaf – top to bottom and edge to edge – you have a well-proofed loaf. Like this one below :) 

When it comes the third factor, we examine the different types of holes, sometimes referred to as ‘alveoli’. If you don’t have an even distribution of holes and some holes are small while other holes form a ‘tunnel’ through the loaf, and the rest of the structure of the crumb is really tight and dense, then your loaf is probably under-proofed. If the tight and dense sections are gummy and spongy, this is also a very good indication that the loaf is under-proofed.

With an over-proofed loaf, the crumb will have small, irregular-shaped holes, often much wider than they are tall, indicating that the dough has been deflating while baking. While this can also appear in under-proofed loaves, over-proofed loaves tend to have far more holes than under-proofed loaves.

A Closer Look at the Sourdough Crumb

Without getting too deep into bread theory, there are several categories that your crumb falls into.

Significantly Under Proofed Sourdough

The first category type is ‘significantly under proofed’. This is when the profile of the bread looks like a frisbee. When you examine the crumb, it has tunnelling holes at the top and a dense structure throughout the rest of the loaf.

Under Proofed Sourdough

I saw a photo of a loaf on Instagram once where the shape of the loaf was perfect, but the crumb of the bread had a few big uneven holes near the top of the loaf. The person who posted was proud of their loaf but the sourdough bread social media mafia soon brought him back down to earth with comments like ‘false crumb’ and ‘false rise’ and ‘false hope’. This is the second category of under proofed loaves.

The reason this type of loaf is called ‘false hope’ is because before you cut into the loaf, it looks great. The huge tunnelling is caused by under fermented dough rising to create the tunnel. It will still be dense at the bottom, also indicating under fermentation. This is ‘an under proofed’ loaf.

Well Proofed Sourdough

The next category is what I strive for: a well-proofed loaf. How do we define it? The exterior of the loaf has a tall and well-rounded appearance, and an ear – although the size of the ear is influenced by the hydration, the type of flour, and the heat of your oven. Once sliced, the loaf has holes of various sizes from the base to the top of the loaf and from side to side, with no dense section at the bottom of the loaf.

Over Proofed Sourdough

The first over proofed example is just called ‘over proofed’. The loaf has not risen as much as a well-proofed loaf as the gluten structure has already begun breaking down. Examine the crumb and you will see an uneven distribution of holes and hole sizes, as well as some density at the bottom of the loaf.

Another tell-tale sign of over proofing is that the crust and the crumb separate, generally at the top with bubbles, but it can also happen at the bottom of the loaf. I once had a loaf like this baked so bad I could virtually slide my bread knife all the way along the length of the loaf in the gap. That was a loaf to forget. Except I haven’t!

Significantly Over Proofed Sourdough

The last category is the ‘significantly over proofed’ loaf. Like the ‘significantly under proofed’ it has a disappointing frisbee-like profile. Once you cut into the loaf and examine the crumb you will see that it has a lot more holes than the ‘significantly under proofed’ loaf, but they are small and rough looking. The crumb will generally be pulling away from the thin crust as well, which does not happen in a highly under proofed loaf.

So here’s how to bake a perfect sourdough loaf.

Tips to How to Bake a Perfect Sourdough Loaf

The Sourdough Starter

It all starts with the starter. If your starter is not at least doubling in size after being fed, you simply won’t get a good rise (oven spring) in your loaf and it will be flat-looking regardless of your proofing time and technique.

I like my starter to triple in size and be very active by four hours after feeding. This feeding, below, from yesterday, shows just how active the starter was five hours post feeding! This is still in the window to bake using this starter, as it’s at full strength and has not started to fall.

Feeding the Sourdough Starter for Baking

If you are daily-feeding your mature starter, you should keep track of how long it takes to peak after feeding and also how long it stays at peak. Once my starter has reached its peak, I generally have a 20-30 minute window to begin making my dough. How do you know if the starter is still at its peak? The top of the starter should be dome-shaped.

To Autolyse or Not to Autolyse?

Autolyse is when you mix the flour and water before adding the starter, usually for around an hour. It is done to essentially kick start the formation of the gluten strands, giving the bread a head-start to a strong structure. I’ve tried this method on and off for four years and I really don’t see the difference in my bread. So I do not use the autolyse method. Please let me know in the comments if you do.

Stretching and Folding the Dough

After I have made the dough, I leave it for 50 minutes covered on the bench. Many bakers leave it for one hour. But living in the tropics, I have a slightly higher room temperature than what most recipes are calculated for, so my times for all activities to make the dough are shorter.

After the 50-minute rest, I do a stretch and fold. This is done by turning the bowl 90% between each fold. I then turn the dough over and tuck the bottom of the dough in to make a ball shape before covering it and waiting another 20-25 minutes before the next stretch and fold.

After three sets of stretch and folds, I test the strength of the dough with the window pane test. This is where you take a small portion of your dough and stretch it in four directions until it’s a thin translucent membrane where you can see light through it.

If you can achieve that and the dough does not break during the stretch, it’s ready for the next step. If the dough breaks, this means the gluten is not well-developed enough. In that case, we do another set of stretch and folds, cover, and wait 20-25 minutes before testing the windowpane again.

The Bulk Rise

Once you have achieved a good, strong windowpane effect, there is an extra step that professional sourdough bakers and many home bakers will do. They place the dough evenly stretched out in a plastic container, marking the level of the dough, then let it rest in a warm place until it rises at least another 25% of its bulk. For me, this takes about one hour.

This is generally done because, with a large amount of dough, this step brings extra strength to the gluten structure before dividing the dough into final sizes. I’ve been A/B testing this and even today’s loaf, with a bulk rise of 25%, was no different than the loaves I’ve made over the last several weeks. If you find it works for you, make it part of your process.

Pre-Shape and Shaping the Sourdough Batard

For the pre-shape, I simply dump the dough out of the container and round it up into a boule shape. I’ve found a wooden bench better than a marble countertop for this, because the dough tends to grip better on the wood and it only takes a few turns of the bench scraper to get a tight boule. If you have a really active dough, you will notice small bubbles popping up on the surface of the dough. Always a good sign.

Once I have the pre-shaping done, I sprinkle some rice flour over the top of the dough to stop it sticking to the cloth that I cover it with. Because of the heat and humidity where we live, I leave the pre-shape for just 10 minutes rest on the bench before the final shape. Most bakers leave the pre-shaped dough for 20 minutes before final shaping.

For the final shape, see my step-by-step batard recipe which has photos. And, yes, I’m still using disposable aluminium foil baking tins for proofing.

Proofing the Shaped Sourdough Loaf

I proof the shaped sourdough loaf in the fridge for anywhere between 12 to 36 hours. If you go past 36 hours, you run the risk of over-proofing the dough. I find 18 hours to be my preferred proofing time.

Baking the Sourdough Loaf

I crank our little oven countertop oven as high as it will go, which, judging by our oven thermometer, is around 230°C (445°F). I use a preheated Dutch oven to place the loaf in, and bake it for 20 minutes covered and then 25 minutes uncovered to achieve the depth of colour I like. This is where you can adjust the timing to suit your taste because if you let it go on a little past that golden colour the crust does taste better.

How to Achieve a More Open Crumb in Your Sourdough Loaf

Many people are obsessed with open crumb sourdough loaves to the point where you could slip a golf ball through the holes in the crumb. Once you’ve achieved a technically good loaf of sourdough bread at a hydration level of around 70%, you will have the skills to up the hydration percentage. I stick to a hydration level of around 73%, which you can see the result of in the main feature image of this post.

High hydration bakers, both commercial and home bakers, tend to aim for a hydration level of around 80%. This is not too soupy a mixture to handle and get a good shape with, but any percentage over that gives diminished returns for me.

How to Bake a Perfect Sourdough Loaf – Secrets to Sourdough Baking in Summary

• A very active, well-fed, mature sourdough starter is essential – don’t begin to bake bread unless the sourdough starter is ready.
• Keep in mind a mature sourdough starter that is older than a few months will have more depth of flavour and sourness than a young sourdough starter.
• If you have placed your sourdough starter in the fridge, give it a couple of feeds before trying to bake it to allow it to come up to full strength again.
• Start with a good strong white bread flour – always check the packing date and best-before date – you can add percentages of wholewheat or other wheats incrementally once your bake is good.
• Work out your starting hydration and use a manageable hydration percentage – around 70% – so you can consistently shape loaves as you fine-tune your other factors, such as your baking vessel, bulk fermentation times etc.
• Only change one factor of your bake each time you bake, as changing more than one factor will make it difficult to analyse your finished sourdough loaf.
• When you’re happy with the sourdough bread you’re producing, do experiment with fridge proofing times so you can test the sourness of your loaf – longer proofing will give you more tanginess, which my wife loves.
• At this stage you can up your hydration and experiment with different flours to create your perfect sourdough bread. 

I’d love to know if you found my guide to how to bake a perfect sourdough loaf helpful in your own quest for baking your perfect sourdough loaf. Please do let us know in the comments below.