Head-to-head comparison

Soy Protein Isolate vs Soybeans (mature, cooked): Which Has More Protein?

Both Soy Protein Isolate and Soybeans (mature, cooked) are common enough protein choices that they get compared directly all the time — here's what the actual numbers say.

Soy Protein Isolate

90.0gprotein / 100g

375 cal · 1.0g fat · $$ · Quality 0.9

Soybeans (mature, cooked)

18.2gprotein / 100g

173 cal · 9.0g fat · $ · Quality 0.85

Soy Protein Isolate is in a different weight class here, protein-wise: 90.0g per 100g vs Soybeans (mature, cooked)'s 18.2g, a 71.8g difference that's more about food category than food quality.

Soy Protein Isolate also carries the stronger amino acid profile (one of the highest-quality plant proteins, near-complete on its own), while Soybeans (mature, cooked) is DIAAS-adjusted, complete plant protein.

On price, Soybeans (mature, cooked) wins clearly — $ against Soy Protein Isolate's $$.

Soy Protein Isolate's typical serving also delivers more leucine (2450mg vs Soybeans (mature, cooked)'s 1400mg) — relevant if the goal is maximizing the muscle-protein-synthesis trigger per meal, not just total grams.

Verdict

If raw protein density is what you're optimizing for, Soy Protein Isolate wins clearly. Choose Soybeans (mature, cooked) instead if its lower fat, cost, or prep time matters more to you than the extra grams.

Full nutrition comparison

Per 100gSoy Protein IsolateSoybeans (mature, cooked)
Protein90.0g18.2g
Calories375173
Fat1.0g9.0g
Carbs2.0g8.4g
Fiber1.5g6.0g
Quality score0.90.85
Relative cost$$$
Prep time1 min90 min

Frequently asked

Which has more protein, soy protein isolate or soybeans (mature, cooked)?

Soy Protein Isolate has 90.0g of protein per 100g compared to Soybeans (mature, cooked)'s 18.2g.

Which is lower in calories?

Soybeans (mature, cooked) is lower in calories per 100g, at 173 vs the other's 375.