Does Adding Oat Milk to Coffee Reduce Acidity?

December 24, 2025 •

3 min read

Recent studies suggest that adding certain plant-based milks, including oat milk, can help neutralize coffee's acidity, which can make it gentler on the stomach for those with acid reflux. However, the process is not as simple as it seems, with various factors influencing the final result, from the milk's formulation to the coffee's temperature.

Quick Summary

Adding oat milk to coffee can reduce perceived acidity, primarily due to dilution and the presence of buffering agents in barista-style versions. Factors like temperature shock and the coffee's inherent acidity can cause curdling, but these issues can be avoided with the right technique and product choice. The final effect depends on the specific milk and brewing method.

Key Points

Acidity Reduction: Oat milk can reduce coffee's acidity, with barista versions containing added buffering agents for a stronger neutralizing effect.
Curdling Prevention: Using barista-grade oat milk and tempering it (warming it gently before mixing) can prevent the curdling caused by temperature shock and acidity.
Flavor Profile: Oat milk has a neutral and subtly sweet flavor that balances coffee's bitterness without overpowering its natural notes.
Brewing Method: High-acidity coffee and abrupt temperature changes are the main culprits for curdling, so opting for a darker roast or cold brew is beneficial.
Best Practices: For best results, use a barista-style oat milk, warm it slightly, and add it slowly to your coffee to ensure a smooth, stable emulsion.

The Science Behind Coffee Acidity

Coffee's inherent acidity is a result of several factors, including the type of bean, roast level, and brewing method. The natural organic acids, like chlorogenic and quinic acid, contribute to coffee's distinct flavor profile. While high acidity can be a desirable trait in some specialty coffees, it can also cause digestive discomfort or heartburn for some people. The pH scale, which measures acidity, shows that black coffee typically falls into the acidic range, with an average pH of 4.85–5.10. The goal of adding milk, whether dairy or plant-based, is to increase the beverage's overall pH, making it less acidic.

How Oat Milk Affects Coffee's pH

Oat milk, by itself, is also slightly acidic, with a pH typically between 6 and 7. While this is less acidic than coffee, the natural state of oat milk is not strongly alkaline. The key lies in how the milk is processed, particularly for "barista edition" products. Many commercial barista oat milks include acidity regulators and stabilizers, such as dipotassium phosphate, which help prevent curdling. These additives work as buffering agents, effectively increasing the milk's pH to counteract the coffee's acidity. Therefore, a barista-style oat milk is more effective at neutralizing acid and preventing curdling than a standard, minimally processed oat milk.

The Temperature Shock Problem

One of the most common issues people face when adding oat milk to coffee is curdling. This unsightly separation is often due to temperature shock. When cold, refrigerated oat milk is poured into hot coffee, the sudden temperature change denatures the oat milk's proteins, causing them to coagulate and clump together. This is why many coffee experts and baristas recommend heating the oat milk first or letting the coffee cool slightly before combining them. This gradual mixing process minimizes the shock to the proteins, ensuring a smooth, consistent texture.

A Simple Guide to Reducing Acidity with Oat Milk

To ensure a smooth, low-acid coffee experience with oat milk, follow these steps:

Choose a low-acid coffee bean. Darker roasts generally have lower acidity than lighter or medium roasts. Alternatively, cold brew methods significantly reduce the acidity compared to hot brewing.
Use barista-style oat milk. These products are formulated with stabilizers to withstand heat and acidity, making them far less prone to curdling.
Temper your oat milk. Always warm the oat milk gently before adding it to your hot coffee. Avoid pouring cold milk straight from the fridge into a hot cup.
Pour slowly. Add the oat milk gradually while stirring continuously. This ensures a more even integration of the two liquids, reducing the chances of curdling.
Experiment with brewing methods. If you regularly experience issues, try cold brew coffee. The long, low-temperature extraction process naturally produces a sweeter, less acidic concentrate that pairs beautifully with oat milk.

Comparison Table: Oat Milk vs. Dairy Milk for Acidity


Feature	Oat Milk (Barista Edition)	Dairy Milk	Notes
Acid-Neutralizing Effect	Contains buffering agents like dipotassium phosphate for neutralization.	Contains natural proteins that can neutralize some acid.	Barista oat milks are engineered for greater stability against acidity.
Curdling Susceptibility	High risk with temperature shock and high-acid coffee if not barista-grade.	Lower risk due to different protein structure and fat content.	Barista oat milk is formulated to mitigate curdling risks.
Flavor Profile	Neutral and slightly sweet; allows coffee flavor to shine.	Creamier, richer taste that can alter the coffee's flavor.	Oat milk provides sweetness without overpowering the coffee.
Texture	Engineered for creamy, silky microfoam.	Natural fats and proteins create smooth, rich texture and foam.	Barista oat milk is a favorite for latte art due to foamability.

Conclusion: Oat Milk as an Acidity Solution

Yes, adding oat milk to coffee can effectively reduce acidity, especially when using barista-grade versions formulated with added stabilizers. The neutralizing effect, combined with its creamy texture and mild flavor, makes it an excellent plant-based alternative for those seeking a gentler coffee experience. However, success requires attention to detail—using a barista blend, tempering the milk, and choosing a less acidic coffee will provide the best results. By understanding the roles of pH and temperature, you can enjoy a smoother, more balanced cup without the discomfort of high acidity. For further details on the interactions between plant-based milks and coffee, a useful resource is Why Does Oat Milk Curdle in Coffee? (+ How To Prevent It).

Frequently Asked Questions

Oat milk is not naturally alkaline; its pH typically ranges between 6 and 7, making it slightly acidic. Barista-style versions contain added acidity regulators to prevent curdling in coffee, which makes them function more like a buffer.

Oat milk curdles in coffee primarily due to two factors: the high acidity of coffee and the temperature shock of adding cold milk to a hot beverage. This causes the oat milk's proteins to separate and clump together.

Barista-style oat milk is specifically formulated for hot beverages. It contains stabilizers and added fats that create a more stable emulsion, making it less likely to curdle when mixed with hot, acidic coffee and producing better foam.

Yes, highly acidic coffee, such as a light roast, is more likely to cause oat milk to curdle. Darker roasts and cold brew methods produce a less acidic coffee that pairs more smoothly with oat milk.

Yes, you can minimize curdling by warming your regular oat milk gently before adding it to coffee. You can also let your coffee cool down slightly or choose a low-acid coffee to begin with.

Both can reduce acidity through dilution and buffering, but barista-grade oat milk is specifically engineered with added regulators to handle high acidity and temperature shock, potentially offering a more reliable result than standard dairy milk.

Other plant-based milks, such as almond milk and soy milk, can also help reduce the effect of coffee's acidity. Many are naturally more alkaline than oat milk. Trying a low-acid coffee brew is also a good approach.