Why not use a metal spoon with sourdough?

Why Not Use a Metal Spoon with Sourdough? Debunking the Myths and Understanding the Facts

If you’re a sourdough beginner, you might have heard the advice: “Never use a metal spoon with your sourdough starter!” This warning seems to pop up frequently in sourdough circles, blogs, and recipe books, (this is something my mum said to me when I first started baking sourdough) often without much explanation. But is there really any truth to it? As someone who’s spent years nurturing sourdough starters, experimenting with different tools, and learning from trial and error, I’m here to shed some light on this topic. Let’s dig into the facts and bust some myths about using metal with sourdough.

Where Did This Idea Come From?

The idea that you shouldn’t use metal utensils with sourdough starter likely stems from concerns about the interaction between metal and the acidic environment of the starter. Sourdough starters are naturally acidic due to the lactic acid bacteria that help ferment the flour and water mixture, creating the signature tangy flavor of sourdough bread.
Traditionally, it was thought that the acidity in the starter could react with certain metals, potentially affecting the starter’s health or flavor. This advice has been passed down through generations, and like many things in the baking world, it’s become a common “rule” without much scientific backing. But does this rule hold up today?

The Science Behind Metal and Acidity

Let’s break down the facts: Sourdough starter is indeed slightly acidic, usually with a pH between 3.5 and 4.5. This acidity is strong enough to preserve the starter and give the bread its unique taste, but it’s not potent enough to significantly corrode most metals in the short time that utensils are in contact with it.

• Reactive Metals: Metals like aluminum, copper, and zinc are considered reactive, meaning they can corrode or react chemically when exposed to acidic environments. This reaction could potentially leach metallic flavors into your starter, though this would typically require prolonged contact.
• Non-Reactive Metals: Stainless steel, on the other hand, is a non-reactive metal, meaning it resists corrosion and doesn’t react easily with acidic foods. Most modern kitchen tools, including spoons and bowls, are made from stainless steel because it’s durable, safe, and easy to clean.

The Myth Busted: Using Stainless Steel with Sourdough

In my experience, and backed by scientific understanding, using a stainless steel spoon, whisk, or bowl with your sourdough starter is perfectly fine. The brief contact between stainless steel and your starter is not enough to affect the starter’s health, the bread’s flavor, or the integrity of your equipment.
I’ve mixed, stirred, and even made sourdough bread in steel bowls without any issues. The key is ensuring the metal is non-reactive, like stainless steel, which doesn’t interact with the acidity of the starter. Here’s why stainless steel is safe:

• Durability: Stainless steel is tough and won’t chip or crack like some other materials. It’s great for mixing and can handle the acidic environment of a sourdough starter without any problems.
• Non-Reactive Nature: Unlike aluminum or copper, stainless steel doesn’t react with acidic foods, so it won’t alter the taste of your sourdough or harm the starter’s microbial balance.
• Ease of Cleaning: Stainless steel is easy to clean and sanitize, reducing the risk of unwanted bacteria contaminating your starter.

When to Avoid Metal Utensils

While stainless steel is safe, it’s still a good idea to avoid prolonged exposure of your sourdough starter to reactive metals like aluminum, copper, or unlined cast iron, as mentioned above. Here’s why:

• Taste and Color Changes: Reactive metals can impart a metallic taste or alter the color of your starter and dough, especially with prolonged contact.
• Possible Contamination: Over time, reactive metals can leach into acidic foods, which isn’t ideal, especially when working with a living culture like sourdough.
  For example, storing your starter in a copper bowl or constantly stirring it with an aluminum spoon isn’t advisable, as these materials can corrode and affect your starter’s quality.

Best Tools for Sourdough: My Recommendations

While you don’t have to avoid metal entirely, here are some of the best tools I recommend using with sourdough:

1. Glass or Ceramic Bowls: These are non-reactive, easy to clean, and perfect for storing your starter long-term. Plus, they allow you to see your starter’s activity clearly.
2. Stainless Steel Spoons and Whisks: Great for mixing and feeding your starter. The brief contact is harmless, and they’re sturdy enough to handle frequent use.
3. Wooden or Silicone Utensils: These are my go-to choices. Wooden spoons are gentle, and silicone is durable and non-reactive, making them ideal for frequent stirring.
4. Plastic or Silicone Containers: For storing your starter in the fridge, plastic or silicone containers work well as they are non-reactive and come with airtight lids to keep your starter safe.

Final Thoughts

The warning against using metal with sourdough is one of those old-school baking myths that has persisted over time. However, the truth is that modern stainless steel utensils are perfectly safe to use with your starter. The brief interaction won’t harm your starter or affect your bread in any noticeable way.

Ultimately, it’s about using the right kind of metal and ensuring that your sourdough is getting the care it needs—consistent feedings, a clean environment, and the right temperature. So, the next time you reach for that stainless steel spoon, go ahead and stir with confidence!

If you’re curious to learn more about sourdough, from beginner tips to advanced techniques, be sure to check out our sundried tomato sourdough bread recipe, cherry compote sourdough bread, cheese jalapeño sourdough, or our classic sourdough bread recipe, along with articles on sourdough basics.