Smart Lid Spies On Sourdough Starter, Sends Data Wirelessly

March 4, 2021 by Donald Papp 16 Comments

[Justin Lam] created a wonderfully-detailed writeup of his Smart Sourdough Lid project, which was created out of a desire to get better data on the progress and health of his sourdough starters, and to do so more efficiently. The result is a tidy, one-piece lid that constantly measures temperature, humidity, and height of the starter in the jar. Data is sent wirelessly for analysis, but there is also a handy OLED display on the top of the lid that shows immediately useful data like how much the starter has peaked, and how much time has passed since it did so.

The PCB was optimized for size, and not designed with mounting in mind, so a hot-glued machine screw serves as a “button extender”. Issues like this can happen when enclosures are designed after the fact; it’s something to which we can all relate.

We really like how focused the design is, and the level of detail [Justin] goes into to explain his design decisions and describe how well they worked out. This isn’t [Justin]’s first kick at the can when it comes to getting data on his sourdough, after all. We remember his earlier work using computer vision to analyze sourdough starters, and he used what he learned to inform this new design; the smart lid is easier to use and handles data much more efficiently.

The project’s GitHub repository has all the information needed to build your own. The lid is ESP8266-based and integrates a VL6180X time-of-flight (ToF) distance sensor, DHT22 to sense temperature and humidity, and a small SSD1306 OLED display for data. A small custom PCB keeps the modules tidy, and a 3D-printed custom enclosure makes it one tidy package.

[Justin] also analyzes the results he obtained and talks about what they mean in the last part of his writeup, so if you’re into baking and interested in his findings, be sure to give that a look.

Beautiful Sourdough Bread At Home Thanks To Dynamic Recipe Parameterization

May 26, 2020 by Donald Papp 21 Comments

More people are making sourdough at home than ever before, and while it may not take a lot of effort to find a decent recipe, it’s quite another thing to try using recipes to figure out how and why bread actually works. Thankfully, [Makefast Workshop] has turned copious research and hundreds of trials into a dynamic sourdough (and semi-sourdough) bread recipe chock-full of of drop-down options to customize not just ingredients, but baking methods and other recipe elements as well. Want to adjust quantities or loaf styles? Play with hydration or flour type? It’s all right there, and they even have quick-set options for their personal favorites.

In order to do all this, [Makefast Workshop] needed to understand bread at a deeper level than is usually called for. During research, they observed that the format of recipes was often an obstacle to understanding how good bread actually gets made. The reason for this is simple: recipes are presented as standalone documents describing a fixed process; a set of specific steps that, when followed, yield a particular result. What they do not normally do is describe the interplay and balance between ingredients and processes, which makes it difficult to understand how and why exactly the recipe produces what it does. Without that knowledge, it’s impossible to know what elements can be adjusted, and how. The dynamic recipe changes all that.

[Makefast Workshop] performed hundreds of tests, dialing in parameters one by one, to gain the insights needed to populate their dynamic recipe. It’s got clear processes and drop-down options that dynamically update not just the recipe steps, but also the URL. This means that one can fiddle the recipe to one’s desire, then simply copy and paste the URL to keep track of what one has baked.

When it comes to thoughtful approaches to food, this certainly isn’t [Makefast Workshop]’s first rodeo. We covered their beautiful directions for creating delicious speculoos, complete with effective 3D printed molds for a modern twist on a Belgian classic.

Yeast Is A Hot Commodity; Brewing And Breadmaking During Lockdown

April 13, 2020 by Jenny List 69 Comments

In the recent frenzy of stocking up with provisions as the populace prepare for their COVID-19 lockdown, there have been some widely-publicised examples of products that have become scarce commodities. Toilet paper, pasta, rice, tinned vegetables, and long-life milk are the ones that come to mind, but there’s another one that’s a little unexpected.

As everyone dusts off the breadmaker that’s lain unused for years since that time a loaf came out like a housebrick, or contemplates three months without beer and rediscovers their inner home brewer, it seems yeast can’t be had for love nor money. No matter, because the world is full of yeasts and thus social media is full of guides for capturing your own from dried fruit, or from the natural environment. A few days tending a pot of flour and water, taking away bacterial cultures and nurturing the one you want, and you can defy the shortage and have as much yeast as you need.

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Engineering Your Way To Better Sourdough (and Other Fermented Goods)

January 8, 2020 by Kristina Panos 23 Comments

Trent Fehl is an engineer who has worked for such illustrious outfits as SpaceX and Waymo. When he got into baking, he brought those engineering skills home to solve a classic problem in the kitchen: keeping a sourdough starter within the ideal, somewhat oppressive range of acceptable temperatures needed for successful fermentation.

A sourdough starter is a wad of wild yeasts that you make yourself using flour, water, and patience. It’s good for a lot more than just sourdough bread — you can scoop some out of the jar and use it to make pancakes, waffles, pretzels, and a host of other bread-y delights. A starter is a living thing, a container full of fermentation that eats flour and has specific temperature needs. Opinions differ a bit, but the acceptable temperature range for active growth is about 60 F to 82 F. Too cold, and the starter will go dormant, though it can be revived with a little love. But if the starter gets too hot, all the yeasts and bacteria will die.

While there are of course commercial products out there that attempt to solve this problem of temperature control, most of them seem to be aimed at people who live in some wonderland that never gets warmer than 80F. Most of these devices can’t cool, they only provide heat. But what if you live in a place with seasons where the climate ranges from hot and humid to cold and dry?

The answer lies within Chamber, a temperature-regulated haven Trent created that lets these wild yeasts grow and thrive. It uses a Peltier unit to heat and cool the box as needed to keep the mixture fermenting at 26°C /78.8°F.

Thanks to the Peltier unit, Trent can change the temperature inside the chamber simply by alternating the direction of current flow through the Peltier. He’s doing this with an H-bridge module driven by a Raspberry Pi Zero. When it starts to get too warm in the chamber, the fan on the outside wall vents the heat away. A second fan inside the chamber pulls warm air in when it gets too cold.

Trent says that Chamber performs really well, and he’s recorded temperatures as low as 60F and as high as 82F. He mostly uses it for sourdough, but it could work for other temperature-sensitive food sciences like pickling, growing mushrooms, or making yogurt. We think it could be ideal for fermenting kombucha, too.

Chamber works well enough that Trent has put further development on the back burner while he makes use of it. He does have several ideas for improvements, so if you want to help, check out his website and Github repo.

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Raspberry Pi Tracks Starter Fermentation For Optimized Sourdough

June 27, 2018 by Dan Maloney 8 Comments

Those of you who’ve never had a real sourdough have never had real bread. Good food fights back a little when you eat it, and a proper sourdough, with its crispy crust and tangy center, certainly fits the bill. Sourdough aficionados, your humble writer included, all have recipes that we pretend are ancient family secrets while in reality we’re all just guessing. Sourdough is partly science, partly art, but mostly delicious black magic.

In an effort to demystify his sourdough process, [Justin Lam] has gone digital with this image processing sourdough starter monitor. Sourdough breads are leavened not by the addition of brewers yeast (Saccharomyces cerevisiae), but by the inclusion of a starter, a vibrant ecosystem of wild yeasts that is carefully nurtured, sometimes for years. Like any other living thing, it needs to be fed, a task that should happen at the point of maximum fermentation. Rather than guess when this might be, [Justin] used a Raspberry Pi Zero and PiCam to capture a time-lapse video of the starter as the beasties within give off their CO₂, thus expanding it up inside its container. A little Python does the work of thresholding and finding the top of the starter as it rises, allowing [Justin] to plot height of the starter over time. He found that peak height, and therefore peak fermentation, occurs about six hours after feeding. He has used his data to better inform his feeding schedule and to learn how best to revive neglected starters.

Surprisingly, this isn’t the first time we’ve discussed sourdough here. It seems that someone uses Git for iterative sourdough recipe development, and we once featured a foundry made from a pyrolyzed loaf of sourdough.

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Breadboarding: Git For A/B Testing Actual Bread

May 9, 2018 by Al Williams 17 Comments

We will be the first to admit, we like to use Git for a lot of things that are probably off the beaten path. But now thanks to [hendricius] you can find out how to make your own bread on GitHub. Let’s get one thing straight. This isn’t the breadmaker fad from a while back, although we are surprised we don’t see more hacked together breadmakers with Internet connectivity. This is old-fashioned bread baking with a bowl, some ingredients, and an oven or another heat source.

You might think this is just using Git as a repository for recipes, but it is more than that. According to [hendricius]:

Learn how to master the art of baking the programmer way. If you love programming, you will also enjoy breaking some bread. A/B test, iterate and ultimately become a self-taught baker. This repository is dedicated to becoming your bread manifesto with useful tricks and hacks. Furthermore, the goal is to illustrate how easy making bread is and that you can get started today without expensive tools.

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