What You’ll Learn
- What enzymes are.
- How amylase affects starch.
- How protease affects proteins.
- Why enzymes matter to fermentation.
- How temperature and time change enzyme activity.
Quick Answer
Enzymes in flour help break starches into smaller sugars and proteins into smaller components. Amylase activity supplies fermentable sugars to microorganisms, while protease activity affects dough extensibility and strength. Too much enzymatic breakdown can eventually weaken dough.
This lesson is part of our Science of Sourdough section: “Understand what’s happening inside your dough.”
What Are Enzymes?
Enzymes are biological catalysts that speed up chemical reactions without being consumed in the process.
Amylase
Amylase breaks starch into smaller sugars, making more food available to yeast and bacteria.
Protease
Protease breaks down proteins and can increase dough extensibility.
Why This Helps Fermentation
Microorganisms cannot use intact starch efficiently, so enzymatic breakdown helps provide accessible sugars.
Why Too Much Breakdown Is a Problem
Long, warm or highly acidic fermentation can contribute to excessive structural weakening.
Enzymes and Browning
Sugars produced from starch also contribute to crust colour during baking.
Why This Matters in the Kitchen
The science matters only when it helps you make better decisions. Use it to understand what you can see, smell and feel in your starter and dough.
From Our Workshop
A dough that suddenly becomes loose late in fermentation is not always ‘too much water’. Enzymatic and acidic breakdown can be part of the story.
Bake Slower Tip
Time and temperature affect both microbes and enzymes, which is why fermentation is more than just gas production.
Common Mistake
Do not think of flour as chemically inactive until yeast arrives. Flour already contains active enzymes.
Today You Learned
- Enzymes accelerate reactions.
- Amylase breaks down starch.
- Protease affects proteins.
- Enzymes support fermentation.
- Excessive breakdown can weaken dough.
Frequently Asked Questions
Are enzymes naturally present in flour?
Yes.
Does autolyse activate enzymes?
It gives flour time to hydrate and enzymatic activity to begin.
Can enzymes make dough sticky?
Excessive breakdown can contribute.
Do wholegrain flours contain more enzyme activity?
They can behave differently because more of the grain is present.
Are enzymes destroyed during baking?
High baking temperatures eventually denature them.
Tools & Ingredients Mentioned in This Guide
These products are directly related to the measurements, ingredients or starter care discussed in this lesson.
Turn the Science Into Better Bread
Understanding enzymes explains why time can improve dough—and why too much time can weaken it.
Continue Learning
Next lesson: Gluten Development in Sourdough
What this means at the bench
The useful question is not only what is happening scientifically, but what you can observe. Connect the science to changes in rise, aroma, acidity, dough strength, extensibility and fermentation speed in your own kitchen.