So a lot of people ask me what's the best type of flour to use for a sourdough starter and why do I use the specific types of flour that I do and so on. And while I have my ideas, I realize that I've never actually tested it. So in this video I designed a little experiment to test exactly that. So let's get into it. If you're new here, my name is Charlie and on this channel I show you how to create delicious food using simple ingredients and techniques so that you can become a more confident home cook. So let's talk about the experiment. So like I said, the goal of this experiment was to figure out what is the best type of flour to use for a sourdough starter and does it even matter. So to test it, I took my main sourdough starter and divided it into five separate jars, placing 50 grams of it in each jar. Then I fed each of them every day for a week with five different types of flour and flour blends. Then at the end, I baked a loaf with each one and observed the final results. So the five different types of flour I used were number one, a blend of 50% whole wheat and 50% unbleached all purpose flour. The second starter was fed using 50% whole grain rye flour and 50% unbleached all purpose flour. The third was fed using 100% whole wheat flour. The fourth was fed using unbleached bread flour. And the fifth was fed using bleached all purpose flour. So I fed each starter every 24 hours with a ratio of 25 grams of starter to 50 grams of flour and 50 grams of cold tap water. So here you can see the first feeding along with a quick time lapse showing how each flour performed after that first feeding. As you can see, there wasn't much difference yet between the flowers. The bleached all purpose starter rose and fell the fastest and the rye starter reached the highest maximum height, but they all showed some decent activity. I expected that throughout the week however, the discrepancies would become more and more clear as each starter took on the characteristics of the flour that it was being fed with. So as I said, I just continued to feed them every day for a week, then took another time lapse after the final feeding before I baked with them. And I was surprised to see that every starter still remained very active after that first week of feeding. The whole wheat starter was the slowest to rise and never quite reached the same height as the other four, but it did still rise a pretty significant amount. Aside from the rise though, I wanted to compare some other aspects of the starter and to me the next most important aspect was the smell. Every starter had a distinctly acidic smell as you'd expect, but some were definitely better than others. The bread flour starter had the most pleasant, fruity smell with some nice hints of acidity, but both of the 50-50 blends smelled pretty nice too. In those blends however, I did notice a bit more of a floury wheaty scent, probably due to the whole wheat content of those starters. Now the bleached all-purpose starter, although it did have that nice acidic, somewhat fruity smell to it, also had some subtle raw flour almost chemical-like smells to it that weren't very pleasant. And the 100% whole wheat starter was definitely last in terms of smell. It had developed quite a few off smells, namely a pretty distinct wet flour sort of barnyardy smell. So clearly each starter had taken on its own unique characteristics, but I was curious to see how that would translate into a loaf of bread. Now for the bread, I used my basic sourdough bread recipe which I've made an entire video about that I'll leave linked in the description below, and I won't go into all the details here, but essentially to make each levan I mixed 20 grams of starter, with 30 grams of flour and 30 grams of water, and let it rise for about 12 hours. And of course for the levan's, I used the same type of flour that I had been feeding each starter with throughout the week. I had to bake in two separate batches since I didn't have enough vanitins to bake all five loaves at once, so that's why you only see me preparing three levan's here. So I did the other two the next day following the exact same process and timing. And once the levan's were mixed, the process was the exact same for all five loaves. So I mixed the dough in the morning, let it rest for about 30 minutes, then performed five sets of folds spaced out at 25 minute intervals. Then I divided and shaped the dough and placed it into vanitins for the final rise. Since I only had two oval vanitins, I'd use a 9x5 loaf pan lined with a dish towel for my third loaf. Then after about five hours in the refrigerator, I scored and baked my loaves, then let them cool and cut into them to observe the final results. And I was surprised to see that every loaf rose nicely and had a pretty decent open crumb structure. The loaf made with the whole wheat starter did produce a slightly denser crumb, but overall it was still a pretty good result. And the best crumb structure was achieved by the bread using the 50% rye and 50% all-purpose starter. The loaf made with the 50% whole wheat, 50% all-purpose starter was slightly misshapen, but I would attribute that to the fact that it was risen in the 9x5 loaf pan rather than a proper vanitin. As far as smell and taste, the breads all had the exact same smell to me with that nice, bready, tangy scent that typical sourdough bread has. And the loaves also all tasted very similar to each other. Due to the technique I used, my loaves typically turn out pretty mild tasting, and that was the case here too. The loaf made with the 50% whole wheat, 50% all-purpose blend was slightly tangier than the rest, but aside from that I couldn't tell any differences flavor-wise. Now keep in mind that I began with a fully active starter and just performed maintenance feelings for this experiment, so the results aren't necessarily indicative of whether you could create a starter from scratch using any type of flour, but that's something I do plan to test in the near future. I do however think it's safe to conclude that you can at least keep your starter alive using any type of flour, and for the best results you should feed with a maximum of about 50% whole wheat flour and then fill in the rest with any type of white flour. Personally, I'm going to stick to using unbleached white flour just to be sure, but as this experiment showed, if all you can get your hands on is a bleached white flour, you don't have to worry about it killing off your starter. So I hope this video helped you out, and if you're still working on creating an active sourdough starter or you need some tips troubleshooting, be sure to check out one of the videos in the bottom right corner of the screen. So there you go. I'll see you all in the next one.