#008
In this LAB note
Question · Hypothesis · Method · Results · What Failed · What We Learned · What Changed at MOMS
Question
Once a shake already meets its roughly 30g protein target from its solid ingredients, does the choice of liquid base still change its formulation quality, and if so, through what mechanism other than protein?
Hypothesis
We expected the base to be nearly neutral. If two recipes both land near 30g of protein, the milk should behave like a carrier, a way to reach a drinkable consistency, and shouldn’t move our internal Score much. If anything did move, we assumed soy would edge ahead simply by adding a few grams of complete protein.
Method
We drew on two published lines. Vanga and Raghavan (Journal of Food Science and Technology, 2018) profiled plant milks and showed soy carries by far the most protein, closest to cow’s milk, while rice milk is the lowest in protein and highest in carbohydrate, and almond milk is dilute in nearly everything. Shkembi and Huppertz (Foods, 2023) measured glycemic responses directly and reported rice milk at a glycemic index of 86 versus soy at 34, meaning the base itself reshapes the carbohydrate load a drink delivers. Internally, we grouped all 201 recipes in our formulation database by their primary liquid base and compared mean Score, mean carbohydrate, protein grams, and how often each base produced a perfect Score of 20.
Results
Protein was essentially flat across bases (32.4 to 33.7g), confirming that base choice was not about hitting the protein target. Yet Score tracked the base anyway: soy averaged 15.14 (n=36) and soy-containing blends 15.52 (n=27); coconut 15.06 (n=50) and oat 15.14 (n=29) sat in the middle; rice 14.58 (n=24) and almond 14.09 (n=23) trailed. Every one of the six recipes that scored a perfect 20 used soy or coconut: four on soy (EY-W4-CALM-001-V1, Soy Milk 150ml, 33.3g protein; EI-W2-WARM-001-V1, Soy Milk 300ml, 37g protein; WAI-W3-NUTR-001-V1, Soy Milk 195ml, 36.5g protein) and two on coconut (MY-W2-DETOX-001-V1, Coconut Milk 300ml, 34.6g protein, 29.6g carb), and none used almond or rice. Rice bases carried the highest mean carbohydrate of any group (46.8g) and the lowest ceiling (best Score 17); MY-W3-GUT-004-V1 on Rice Milk 150ml reached 62g of carbohydrate and scored only 13, precisely the glycemic-load penalty the Shkembi data would predict.
What Failed
The stronger version of our own follow-up idea, that the base predicts the Score, did not survive the data. Across all 201 recipes the correlation between carbohydrate and Score was only -0.18: real, but weak. Oat milk makes the point. Despite the second-highest mean carbohydrate load of any base (43.4g), it matched soy at 15.14, because its beta-glucan fiber offsets the glycemic cost the raw carbohydrate number implies. And a dilute base can still be rescued by the rest of the formula: MY-W2-DETOX-005-V1, built on rice milk, held carbohydrate to 37.7g and reached a Score of 15. The base tilts the odds; it does not decide the outcome.
What We Learned
The liquid base matters, but not for the reason we first guessed. It is not adding or subtracting protein; that was matched everywhere. It is quietly reshaping the rest of the macro envelope. Rice milk inflates fast carbohydrate, almond milk contributes almost nothing per calorie and forces the solid ingredients to carry the entire nutritional load, while soy and coconut give more back for the calories they cost. The base is an ingredient, not a solvent.
What Changed at MOMS
We now treat the base as an active ingredient rather than a background liquid. Soy and coconut are our default anchors. Rice milk is capped in volume and always paired with a fiber source, or a beta-glucan carrier such as oats, to blunt its glycemic contribution, and we now track the grams of carbohydrate that come from the base specifically, not just the recipe total. Almond milk is reserved for recipes that already carry their fiber and micronutrients elsewhere; it is never asked to be the nutritional backbone.
References
1. Vanga SK, Raghavan V. How well do plant based alternatives fare nutritionally compared to cow’s milk? Journal of Food Science and Technology. 2018;55(1):10–20. 2. Shkembi B, Huppertz T. Glycemic Responses of Milk and Plant-Based Drinks: Food Matrix Effects. Foods. 2023;12(3):453.
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