---
title: "How to tell if a bread is truly naturally leavened"
type: article
brand: santopane
locale: en
---

# How to tell if a bread is truly naturally leavened

Not every bread sold as "naturally leavened" is made with levain alone. See what to look for on the label, the signs in the bread itself and the right questions to ask your bakery.

**A truly naturally leavened bread rises with levain alone, the culture of wild yeasts and lactic acid bacteria kept by the bakery, with no commercial yeast.** The quickest way to check is the ingredient list: if it says “baker's yeast”, “yeast” or “baking powder”, the bread is not purely naturally leavened, whatever the packaging claims.

The term has become a selling point, and shelves have filled with breads that use the name without the process. This guide shows what to look for on the label, what to notice in the bread and what to ask the people who make it.

## So what is natural fermentation?

It is the oldest way to make bread rise. Flour and water, fed every day, become a living culture of yeasts and lactic acid bacteria: levain, also called natural leaven, sourdough starter or _massa madre_. The yeasts produce the gas that lifts the dough; the bacteria produce lactic and acetic acid, which give flavour and help the bread keep.

This work is slow. While a commercial-yeast bread can be ready in a few hours, a levain bread needs many hours of fermentation. That time is where the aroma, crust and texture that set the two apart are born.

## What is “sourfaux”?

It is the nickname the Real Bread Campaign, a British campaign for real bread, gave to breads sold as _sourdough_ that are not. The three most common tricks are:

-   **Commercial yeast alongside the levain.** A little natural leaven for the name, commercial yeast for speed.
-   **Powdered or dried sourdough as a flavouring.** It goes in to add acidity and colour to the crumb, while the commercial yeast does the work.
-   **Acidulants.** Lactic acid, acetic acid or vinegar added to imitate the flavour that only long fermentation would produce.

None of these breads is harmful because of it. But they are not what they claim to be, and anyone paying for natural fermentation should get natural fermentation.

## How to read the label

In Brazil, the ingredient list comes in descending order of quantity: the first item is the one that weighs most in the recipe. Look for these names:

| On the label | What it means |
| --- | --- |
| Natural leaven, levain | The basis of the process. In a purely naturally leavened bread, it is the only leavening on the list. |
| Baker's yeast, yeast, _Saccharomyces cerevisiae_ | Commercial yeast. Alongside levain, it points to a hybrid bread. |
| Baking powder | Bicarbonate and similar, typical of cakes. It is not fermentation. |
| Flour improver, emulsifiers (such as sodium stearoyl lactylate or mono- and diglycerides) | They standardise and speed up the dough. Long fermentation does that job on its own. |
| Preservatives (such as calcium propionate or sorbic acid) | They extend shelf life. |
| Lactic acid, acetic acid, vinegar, “flavouring” | They imitate the acidity of long fermentation. |
| Sugar or syrup in a savoury bread | They help browning and feed a fast yeast. |

We wrote about this habit in [The Truth in the Fine Print](/en/jornal/importancia-ler-rotulos-alimentos-ribeirao-pires).

## Signs in the bread itself

Without a label, at a bakery, the bread also tells its story. No single sign is proof, but together they say a lot:

-   **Crust.** Thick, well baked, with shades from golden to almost chestnut, and it crackles when you press it.
-   **Crumb.** Moist, slightly glossy, with irregular holes. Large holes come from technique and hydration, not only from the leaven, so they are not proof on their own.
-   **Aroma and flavour.** Notes of toasted grain and a light acidity. Too sour can be a sign of acidulants; a good levain bread is balanced.
-   **How it ages.** It hardens slowly and takes a while to mould, without preservatives. A bread that stays the same for two weeks in its bag has not aged naturally.

## Naturally leavened and ordinary bread, side by side

|  | Naturally leavened | Ordinary industrial bread |
| --- | --- | --- |
| Leaven | Levain kept at the bakery | Commercial baker's yeast |
| Fermentation time | Many hours, often with a cold rest | A few hours |
| Typical ingredients | Flour, water, salt and levain | Flour, water, yeast, sugar, fat, improvers, preservatives |
| Flavour | Complex, slightly acidic | Neutral or sweetish |
| Keeping | Ages slowly thanks to natural acidity | Depends on preservatives |

## Three questions to ask your bakery

1.  **Do you use commercial yeast alongside the levain?** The honest answer is yes or no, plainly.
2.  **How long does the dough ferment?** Anyone who works with long fermentation can tell you.
3.  **Can I see the ingredient list?** A bakery that makes real bread is proud of it.

## Quick questions

### Does naturally leavened bread contain gluten?

Yes. Long fermentation breaks down part of the gluten proteins, and many people with sensitivity report digesting it better, but the bread still contains gluten and **is not safe for people with coeliac disease**. We explain the science in [Pre-Digested Gluten and Blood Sugar Spikes](/en/jornal/gluten-pre-digerido-e-pico-de-glicemia-o-que-a-fermentacao-natural-faz-pelo-seu-corpo).

### Is naturally leavened bread always sour?

No. Acidity depends on the levain, temperature and time. Many levain breads, ours included, have a light acidity that comes through more as depth of flavour than as sourness.

### Is wholemeal bread always naturally leavened?

No. Wholemeal describes the flour; natural fermentation describes the leaven. A bread can be wholemeal and made with commercial yeast, or white and made with levain.

## How it works at Santo Pane

All our breads rise with levain, without commercial yeast, without improvers and without preservatives. The classic rustic loaf is made with flour, water, salt and levain, and goes through a long cold fermentation, as we describe in [The Return of Real Bread](/en/jornal/o-resgate-do-pao-verdadeiro). Each product has its description and allergens on its own page; start with the [Classic Italian Rustic Bread](/en/produtos/68bf1e7e62ec360dbf1a53bc), the house favourite.

We bake once a week in Ribeirão Pires and deliver to Ribeirão Pires, Rio Grande da Serra, Mauá, Santo André, São Bernardo do Campo, São Caetano do Sul and part of São Paulo. See [this week's menu](/en/cardapio) and enter your postcode on [Closer to You](/en/mais-perto).

## Orders and questions

- WhatsApp: https://wa.me/5511984807000
- Instagram: @santopaneoficial (https://instagram.com/santopaneoficial)

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  "articleBody": "A truly naturally leavened bread rises with levain alone, the culture of wild yeasts and lactic acid bacteria kept by the bakery, with no commercial yeast. The quickest way to check is the ingredient list: if it says “baker's yeast”, “yeast” or “baking powder”, the bread is not purely naturally leavened, whatever the packaging claims. The term has become a selling point, and shelves have filled with breads that use the name without the process. This guide shows what to look for on the label, what to notice in the bread and what to ask the people who make it. So what is natural fermentation? It is the oldest way to make bread rise. Flour and water, fed every day, become a living culture of yeasts and lactic acid bacteria: levain, also called natural leaven, sourdough starter or massa madre. The yeasts produce the gas that lifts the dough; the bacteria produce lactic and acetic acid, which give flavour and help the bread keep. This work is slow. While a commercial-yeast bread can be ready in a few hours, a levain bread needs many hours of fermentation. That time is where the aroma, crust and texture that set the two apart are born. What is “sourfaux”? It is the nickname the Real Bread Campaign, a British campaign for real bread, gave to breads sold as sourdough that are not. The three most common tricks are: Commercial yeast alongside the levain. A little natural leaven for the name, commercial yeast for speed. Powdered or dried sourdough as a flavouring. It goes in to add acidity and colour to the crumb, while the commercial yeast does the work. Acidulants. Lactic acid, acetic acid or vinegar added to imitate the flavour that only long fermentation would produce. None of these breads is harmful because of it. But they are not what they claim to be, and anyone paying for natural fermentation should get natural fermentation. How to read the label In Brazil, the ingredient list comes in descending order of quantity: the first item is the one that weighs most in the recipe. Look for these names: On the label What it means Natural leaven, levain The basis of the process. In a purely naturally leavened bread, it is the only leavening on the list. Baker's yeast, yeast, Saccharomyces cerevisiae Commercial yeast. Alongside levain, it points to a hybrid bread. Baking powder Bicarbonate and similar, typical of cakes. It is not fermentation. Flour improver, emulsifiers (such as sodium stearoyl lactylate or mono- and diglycerides) They standardise and speed up the dough. Long fermentation does that job on its own. Preservatives (such as calcium propionate or sorbic acid) They extend shelf life. Lactic acid, acetic acid, vinegar, “flavouring” They imitate the acidity of long fermentation. Sugar or syrup in a savoury bread They help browning and feed a fast yeast. We wrote about this habit in The Truth in the Fine Print. Signs in the bread itself Without a label, at a bakery, the bread also tells its story. No single sign is proof, but together they say a lot: Crust. Thick, well baked, with shades from golden to almost chestnut, and it crackles when you press it. Crumb. Moist, slightly glossy, with irregular holes. Large holes come from technique and hydration, not only from the leaven, so they are not proof on their own. Aroma and flavour. Notes of toasted grain and a light acidity. Too sour can be a sign of acidulants; a good levain bread is balanced. How it ages. It hardens slowly and takes a while to mould, without preservatives. A bread that stays the same for two weeks in its bag has not aged naturally. Naturally leavened and ordinary bread, side by side Naturally leavened Ordinary industrial bread Leaven Levain kept at the bakery Commercial baker's yeast Fermentation time Many hours, often with a cold rest A few hours Typical ingredients Flour, water, salt and levain Flour, water, yeast, sugar, fat, improvers, preservatives Flavour Complex, slightly acidic Neutral or sweetish Keeping Ages slowly thanks to natural acidity Depends on preservatives Three questions to ask your bakery Do you use commercial yeast alongside the levain? The honest answer is yes or no, plainly. How long does the dough ferment? Anyone who works with long fermentation can tell you. Can I see the ingredient list? A bakery that makes real bread is proud of it. Quick questions Does naturally leavened bread contain gluten? Yes. Long fermentation breaks down part of the gluten proteins, and many people with sensitivity report digesting it better, but the bread still contains gluten and is not safe for people with coeliac disease. We explain the science in Pre-Digested Gluten and Blood Sugar Spikes. Is naturally leavened bread always sour? No. Acidity depends on the levain, temperature and time. Many levain breads, ours included, have a light acidity that comes through more as depth of flavour than as sourness. Is wholemeal bread always naturally leavened? No. Wholemeal describes the flour; natural fermentation describes the leaven. A bread can be wholemeal and made with commercial yeast, or white and made with levain. How it works at Santo Pane All our breads rise with levain, without commercial yeast, without improvers and without preservatives. The classic rustic loaf is made with flour, water, salt and levain, and goes through a long cold fermentation, as we describe in The Return of Real Bread. Each product has its description and allergens on its own page; start with the Classic Italian Rustic Bread, the house favourite. We bake once a week in Ribeirão Pires and deliver to Ribeirão Pires, Rio Grande da Serra, Mauá, Santo André, São Bernardo do Campo, São Caetano do Sul and part of São Paulo. See this week's menu and enter your postcode on Closer to You.",
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