Soy Protein Isolate
90.0gprotein / 100g375 cal · 1.0g fat · $$ · Quality 0.9
Tofu (firm)
17.3gprotein / 100g144 cal · 8.7g fat · $ · Quality 0.91
This isn't close. Soy Protein Isolate packs 90.0g of protein per 100g against Tofu (firm)'s 17.3g — a 72.7g gap driven mostly by how concentrated or diluted each food naturally is.
Neither has a meaningful edge on protein quality; they're close enough on amino acid profile that it isn't a differentiator here.
Tofu (firm) is the more budget-friendly pick ($ vs $$ for Soy Protein Isolate), worth weighing if cost matters more than the other differences here.
Soy Protein Isolate's typical serving also delivers more leucine (2450mg vs Tofu (firm)'s 1300mg) — relevant if the goal is maximizing the muscle-protein-synthesis trigger per meal, not just total grams.
If raw protein density is what you're optimizing for, Soy Protein Isolate wins clearly. Choose Tofu (firm) instead if its lower fat, cost, or prep time matters more to you than the extra grams.
Full nutrition comparison
| Per 100g | Soy Protein Isolate | Tofu (firm) |
|---|---|---|
| Protein | 90.0g | 17.3g |
| Calories | 375 | 144 |
| Fat | 1.0g | 8.7g |
| Carbs | 2.0g | 2.8g |
| Fiber | 1.5g | 2.3g |
| Quality score | 0.9 | 0.91 |
| Relative cost | $$ | $ |
| Prep time | 1 min | 15 min |
Frequently asked
Which has more protein, soy protein isolate or tofu (firm)?
Soy Protein Isolate has 90.0g of protein per 100g compared to Tofu (firm)'s 17.3g.
Which is lower in calories?
Tofu (firm) is lower in calories per 100g, at 144 vs the other's 375.