Try eating half your burn during the ride, not as little as possible. On 1.5 hour rides, I doubt that a significant amount of protein is burned, but on long rides I think it's an issue and one should consume 5-15% protein on the bike or at rest stops. I mix whey and malto for my on-bike fuel for long rides. On short rides of 1-2 hours,, I just use a sports drink or eat a bar.
https://us.humankinetics.com/blogs/e...cise-and-sport