The "Sourfaux" Guide: How to Spot Sourdough Fakes
In the bread aisle, language has become fluid. Words like "artisanal," "traditional," and "rustic" are sprinkled like flour, designed to evoke the image of a baker kneading dough at dawn. But the most abused word of all is Sourdough.
Sourdough is not a flavour. It is a process.
True sourdough is the result of a biological pact: a slow fermentation of flour and water by wild yeast and lactic acid bacteria. This process takes time—often 24 to 48 hours—to break down gluten, neutralise phytates, and develop complex organic acids.
"Sourfaux," a term coined by the Real Bread Campaign [1], refers to bread that mimics the taste of sourdough without the time or the biological benefits [1]. It is fast food dressed up as slow food.
The Litmus Test: Reading the Label
You do not need a microscope to spot a fake. You just need to read the ingredient list. The back of the packet tells a story that the front of the packet is trying to hide.
1. The "Yeast" Giveaway
The Rule: If the ingredients list includes "Yeast" (or Baker's Yeast, Dried Yeast, Commercial Yeast), it is not a true sourdough.
The Science: Authentic sourdough is leavened exclusively by a starter culture. The wild yeast in the starter works slowly. Commercial yeast (Saccharomyces cerevisiae) is bred for speed. If a manufacturer adds commercial yeast, they are bypassing the slow fermentation that defines the pact. They are rushing the rise, which means the bacteria don't have time to pre-digest the grain.
2. The "Vinegar" Cheat
The Rule: If you see "Vinegar," "Acidity Regulator," or "Food Acid (260, 262)," it is likely Sourfaux.
The Science: True sourdough gets its tang from organic acids (lactic and acetic) produced naturally by bacteria over many hours. In Sourfaux, the manufacturer wants the sour taste without the wait. So, they simply add vinegar or acid powder to a standard rapid-rise dough. It tastes sour, but it hasn't been fermented. It is a flavouring, not a function.
3. The "Culture" Confusion
The Rule: Look for "Sourdough Culture" or "Starter" near the top of the list.
The Science: Some labels list "Sourdough Culture" but also list "Yeast." This is a hybrid loaf. It contains a small amount of dried or inactive sourdough powder for flavour, but relies on commercial yeast for the heavy lifting. It's better than standard white bread, but it's hard to know how much.
Case Study: Is Supermarket Sourdough Real?
Let's look at the label of a typical Australian supermarket "Sourdough Vienna":
Ingredients: Wheat Flour, Water, Sourdough Culture (Water, Wheat Flour), Yeast, Iodised Salt, Vinegar, Vitamins (Thiamin, Folic Acid).
The Verdict: This is a Hybrid.
The Good: It contains a culture.
The Bad: It contains Yeast and Vinegar.
The presence of yeast indicates that the primary leavening agent is likely commercial, meaning the fermentation time was likely short (1–2 hours rather than 12+). The vinegar is added to boost the acidity that the short fermentation failed to produce. While it may taste good, it lacks the full digestive benefits of a long-fermented loaf [2].
Compare this to a label from a true artisan bakery:
Ingredients: Certified Organic Wheat Flour, Filtered Water, Sea Salt.
That's it. No yeast. No vinegar. No numbers. The "sour" comes from the process, not a bottle.
Why It Matters
This isn't just about snobbery. It's about biology. The health benefits of sourdough—lowered glycaemic index, degraded gluten, bioavailable minerals—are a direct result of time and bacterial metabolism [3].
When you buy Sourfaux, you are paying a premium for a flavour profile, but you are eating a standard, rapid-rise wheat product. You are getting the taste without the technology.
The Takeaway:
Yeast = Speed. (The enemy of digestibility).
Vinegar = Flavouring. (A chemical shortcut).
Flour + Water + Salt = True Soudough (The Pact)
References
Real Bread Campaign. (n.d.). What is Sourdough? Sustain: The Alliance for Better Food and Farming. Retrieved from https://www.sustainweb.org/realbread/sourdough/
Rizzello, C. G., Portincasa, P., Montemurro, M., Di Palo, D. M., Lorusso, M. P., De Angelis, M., ... & Gobbetti, M. (2016). Sourdough fermented breads are more digestible than those started with Baker's yeast alone: an in vivo challenge dissecting distinct gastrointestinal responses. Nutrients.
Poutanen, K., Flander, L., & Katina, K. (2009). Sourdough and cereal fermentation in a nutritional perspective. Food Microbiology.
Last updated: 10 December, 2025
True sourdough is the result of a biological pact: a slow fermentation of flour and water by wild yeast and lactic acid bacteria. This process takes time—often 24 to 48 hours—to break down gluten, neutralise phytates, and develop complex organic acids.
"Sourfaux," a term coined by the Real Bread Campaign [1], refers to bread that mimics the taste of sourdough without the time or the biological benefits [1]. It is fast food dressed up as slow food.