Give the fridge jar one job
The fridge jar is the culture you keep between bakes. The build for the loaf is the portion you feed to get the right weight of ripe starter. They can come from the same culture without becoming the same job.
If you keep 50 g of seed and add 50 g each of water and flour, you have 150 g after mixing. That is the maintenance feed in King Arthur’s method. If you use a smaller established routine, keep the weights you already know work for your jar. Record the date, give the feed its short counter rest, cover loosely and store it in a consistently cold part of the fridge. A fridge door can experience more temperature changes than a shelf. [1] [2]
If you bake regularly on a weekend, the useful reminder is often when to take the jar out, especially if the culture needs more than one feed to recover.
An illustrative Thursday-to-Saturday routine
This example assumes a regularly maintained starter and a Saturday morning mix. Move the times when the jar or your recipe needs a different window.
| When | What to do | What decides the next step |
|---|---|---|
| Thursday evening | Inspect the jar and refresh a measured portion on the counter. Mark the starting level. | You have a record of the feed and can compare its rise on Friday. |
| Friday morning | Check for expansion, bubbles through the starter and any higher line on the glass. | A familiar rise suggests the jar is getting back to its usual rhythm. Little activity calls for more observation and a further refresh under your method. |
| Friday evening | If the jar is reliably active, build what Saturday’s recipe needs plus a little to retain. | Choose the ratio from a feed you have watched, so you have a realistic morning check window. |
| Saturday morning | Check the build against the recipe’s cues. Weigh out the ripe amount for the dough. | Mix when the culture is ready. Shift the mix if the build is still slow. |
| After taking the recipe portion | Feed the portion you plan to keep and return it to its fridge routine after the counter rest. | Record the new date so you know when it is due for attention. |
What if it barely rises on Friday?
Keep the recipe build off the critical path until the refresh responds. Check the temperature around the jar and look for a clean high-water mark in case you missed the peak. If the starter was healthy and responds more strongly across subsequent feeds, plan from the next reliable rise. If it still looks sluggish on Friday evening, aim for a later mix or another bake day. A deadline on the calendar does not tell you how the starter has recovered. [1]
Keep the recipe build separate when the quantities differ
Say the loaf needs 100 g of ripe starter and you want 20 g left. At 1:2:2, a 120 g build uses 24 g starter and 48 g each of flour and water. If you lose a little to the jar and spoon, round up while preserving the ratio. Choose a build size that fits the loaf and keep your usual maintenance weights for the next week. [1]
A weekly checklist you can keep on the fridge
- Record the date of the last feed and the weights you used.
- Choose the next maintenance day or the day you will take it out to bake.
- Before mixing dough, check that the starter can repeat a familiar rise at room temperature.
- Keep a reserve before weighing starter into the loaf.
- Date the jar again when it goes back into the fridge.
If you skip a week of baking, continue the maintenance routine you follow. A jar with a long gap in its history needs a separate recovery check. If you find fuzzy growth, unusual pink or orange streaks, or other suspicious changes, discard the starter and thoroughly clean the container. [3] [4]
Crispy Crust is being designed with separate reminders for fridge maintenance and pre-bake refreshes. One can tell you the jar is due for care. The other can remind you to take it out early enough to check its rise before a planned mix.
Use the starter feeding calculator to calculate the build you need while keeping a reserve.