Starter Day 5 — Is Your Sourdough Starter Ready?

Practical guide for day 5 of creating a sourdough starter: how to assess activity, common signs, troubleshooting and next steps.

What to Expect

By day 5 you should be able to tell whether your sourdough starter is maturing into a reliable leaven. This page helps you read the signs, perform a simple readiness test, and troubleshoot common issues so you can confidently move to daily maintenance or baking.

What you'll learn:

  • ✓ How to assess starter activity visually and by smell
  • ✓ A simple float test to check leavening power
  • ✓ Troubleshooting steps if activity is low

💭 Many starters are ready on day 5, but some need a few more days. Patience and consistent feedings are the main factors that determine success.

What You Need

Must have:

Starter container

A clear jar or glass jar so you can see activity

⚠️ Get an appropriate container before continuing → more

Kitchen scale

Accurate to the gram for repeatable feedings

⚠️ Buy one — weight-based feedings stabilize activity

Clean spoon or jar spatula

For mixing and scraping

⚠️ Use a sanitized spoon temporarily

Nice to have:

Why day 5 is a useful checkpoint:

Microbial succession is established

By day 5 yeast and lactic acid bacteria usually reach a stable balance that produces visible bubbles and a pleasant tang [1][2].

Starter shows regular rise/fall

Consistent doubling or clear peak-and-fall behaviour after a feeding indicates predictability for baking [1].

You can decide next steps

If active, switch to daily maintenance; if not, continue twice-daily feeds or adjust temperature/ratio [1][2].

Ingredients

For: Starter maintenance/check on Day 5

Mature-looking starter approx. 50–100g available From your Day 4 jar
Water (room temperature) 50–100g Non-chlorinated if possible
Flour (white or whole wheat) 50–100g Same flour used earlier for consistency

Step by Step

Observe → Feed → Track rise → Float test if needed

1

Observe the jar (Morning)

Day 5 morning

Look for bubbles throughout the starter, a noticeable rise, and a slightly tangy smell. Mark the level on your glass jar or clear container.

✓ Bubbles across the surface and body; a rise of ~1.5–2x within a few hours after feeding is a good sign [1].
💡 Small bubbles alone aren't sufficient — look for consistent rise/fall.
2

Discard and refresh (Morning)

When you plan to feed

Discard down to ~50 g starter. Feed with equal parts starter:water:flour by weight (1:1:1) — for example 50g starter + 50g water + 50g flour. Mix with a spoon or jar spatula.

✓ Starter is well-mixed and has no large dry pockets.
💡 Using a kitchen scale keeps feedings consistent [1].
3

Track rise (4–8 hours)

Next 4–8 hours at room temp

Place jar in a warm spot (ideally 24–26°C). Mark the starting level and check at intervals to see the peak.

✓ A healthy starter typically doubles and shows a domed surface at peak within 4–8 hours at these temperatures [1][2].
💡 If your environment is cooler, expect a slower rise and extend checks to 12 hours.
4

Float test (Optional but useful)

At peak

Take a small spoonful of starter and gently drop it into a glass of room-temperature water. If it floats, it has enough trapped gas to leaven bread.

✓ Floats within a few seconds; if it sinks, it may still be active but weak.
💡 The float test isn't perfect (hydration and bubble fragility matter) but it's a practical indication [1].
5

Smell and texture checks

A mature starter smells fruity/tangy, not putrid. Texture should be aerated and somewhat elastic when stirred.

✓ Pleasant acidity and lots of small bubbles; if smell is sharp but clean, it's good for baking [2].
⚠️ If you detect rotten or pink/orange colors, discard and restart.
6

If it's ready: move to maintenance

If the starter reliably doubles and passes the float test, begin daily feedings or refrigerate and feed weekly depending on baking frequency.

✓ Predictable rise and desirable smell; now suitable for small test bakes.

What If It Doesn't Work?

If your starter doesn't show full activity on day 5, here are common causes and fixes:

Very slow or no rise

Likely: Too cool, weak initial yeast population, or feed ratio too large

Fix: Keep starter warmer (24–26°C), use a smaller discard so you feed a higher fraction of mature starter, and use whole grain flour for a nutrient boost [1][2].

→ More info

Strong unpleasant rotten smell

Likely: Unwanted bacteria dominating or contamination

Fix: Discard and restart, sanitize jar; try using bottled or boiled-and-cooled water and fresh flour. If color changes to pink/orange, throw it out [2].

→ More info

Starter sinks in float test

Likely: Not at peak yet or hydration differences

Fix: Wait for a higher peak after feeding and try again; also use the exact portion you would use for dough to judge performance [1].

Hoarse or alcoholic smell

Likely: Starter hungry / underfed

Fix: Increase feed frequency (twice daily) and discard more before feeding until it shows a strong rise.

💪 Most starters simply need more time or small adjustments; continued consistent feeding often resolves issues within a few days [1][2].

What now?

Starter is active
→ Try a small test bake: make a simple 500g dough loaf to confirm leavening power
Starter is not ready
→ Continue twice-daily feedings and warm the jar slightly
I want to understand more
→ Read about the microbes and fermentation behind starter activity
I want reasons to use sourdough
→ Learn why sourdough is valuable

Sources

  1. [1]
    The Perfect Loaf – The Perfect Loaf – Link
  2. [2]
    Plötzblog – Plötzblog – Link