Background
Typically, commercial oat milk brands will use amylase enzymes to break down starches in the oats, which contributes to a better, less ‘starchy’ mouthfeel and adds sugars into the oat milk (though these do not have to be labeled on the product). We’ve developed an alternate method to perform this enzymatic breakdown using malt powder (which contains similar amylases) as opposed to industrially manufactured enzymes. This same theory can be applied to any other grain or starchy ingredient, though oats work quite well in a milk application.
Testing process variations for oat milk to balance flavor mellowing, starch gelatinization, viscosity control, and enzymatic conversion. Standard raw blended oat milk can retain a harsh, un-cooked oat flavor, while heating oats causes gelatinization that thickens the liquid significantly unless starches are broken down.
This experiment compares brief pre-roasting, low-temperature holding below the gelatinization threshold, and starch conversion using diastatic malt powder. Baseline ratio across trials is approximately 150 g oats to 1,000 g water.
Notes and Observations
Thermal & Enzymatic Variations
- Cold Blended vs. Low-Heat Hold: Oat starch gelatinization begins at roughly 152°F. Holding raw oat milk at ~150°F for 15–20 minutes mellows the raw flavor without initiating gelatinization or thickening the liquid.
- Pre-Roasting Oats: Roasting dry oats at 200°F for 8 minutes deactivates endogenous enzymes and provides a mild, cooked oat flavor profile prior to blending.
- Whole Malt Mash: Gelatinized oats were thinned using mildly crushed light Munich malt. Mash was held at ~140°F for enzymatic breakdown, then stepped up to 160°F to complete conversion and de-activate enzymes.
- Diastatic Malt Powder: Using diastatic malt powder avoids a full mash step. Adding the powder once the cooked oats drop to ~150°F allows residual heat to drive rapid liquefaction. Soluble fibers and converted starches (into sugars or longer chain carbohydrates such as dextrins) give the milk a pleasant body.
Flavor & Infusion Possibilities
- Tea Steeping: Cold-steeping tea directly in the base water before blending.
- Oil Emulsion: Emulsifying fats into the mixture improves mouthfeel and body. Since flavor molecules bind well to fats, flavored oils (e.g., roasted pumpkin seed oil or a roasted koji oil) can act as flavor carriers in the emulsion step.
Trial 1: 5 g Diastatic Malt
- Formula: 80 g rolled oats, 500 g water, 10 g neutral oil, pinch of salt, 5 g diastatic malt powder.
- Process: Blended on high for 10 seconds in a Vitamix, heated to gelatinize, then treated with 5 g malt powder.
- Results: Sensorially very pleasant with good body, but left a slight “powdery” malt flavor on the backend. Excellent texture, but needs a more neutral taste profile.
Trial 2: 2 g Diastatic Malt (Optimized Test)
- Results: Reducing diastatic malt powder to 2 g resolved the powdery off-flavor while maintaining complete liquefaction. Yields a clean, neutral oat milk with excellent body.
Formula
Ingredients
- 75 g rolled oats
- 500 g water
- 10 g neutral oil
- Pinch of salt
- 2 g diastatic malt powder
Method
- Blend the rolled oats, water, neutral oil, and salt on high speed in a Vitamix for 10 seconds.
- Heat the mixture until starches gelatinize and thicken.
- Remove from heat and allow the temperature to cool to ~150°F.
- Stir in the diastatic malt powder and let sit for a few minutes while residual heat liquefies the mixture.
- Reheat to ~160°F or higher (without scorching) to deactivate remaining enzymatic activity.
Future Adjustments
- Enzyme Thresholds: Pinpoint the minimum diastatic malt powder needed to achieve complete starch conversion in a short window without leaving residual malt flavor & develop a version that uses more malt or infused with whole malt to lean into the malt flavor.
- Emulsion & Water Ratios: Test oil percentages and oat-to-water ratios around the 150:1,000 baseline to tune mouthfeel for specific beverage applications. Also, developing a specific ‘barista’ variant which is stable enough for acidic beverages is a separate consideration.
- Fat-Soluble Infusions: Test incorporating roasted koji oil into the emulsion step or other toasted grain teas as a final steep to make a ‘milk tea’ type beverage.