I like to mix almonds, walnuts, raisins, cashews and dried blueberries together have them as a snack throughout the day. I've never tried this food source on a 25-50 mile ride. I'd like some thoughts from knowledgeable people on how good this would be to eat during a ride. Anything good to add to this?
The EXPERIENCED CYCLIST, who is not, eg, out of shape after a long winter does not need any food for 50 road miles. This is because his muscles and liver have "learned" to store extra sugar/carbs to provide energy over a long period of time.
But a beginning cyclist who is not, say, already a distance runner or otherwise used to exercising vigorously for several hours DOES need some extra carbs along the way to keep his blood sugar up, not, perhaps, for a 25 mile ride, but for a 50 mile one. (Note, you DON'T want large amounts of fat or protein -- these do nothing to help your sugar levels and they are hard to digest.)
The form of the carbs is not especially critical, other than the food should be chosen for convenience, neatness (you don't, eg, want chocolate smeared all over your hands), and personal taste.
Avoid foods with any significant amount of fat, and avoid spicy or strongly flavored foods -- these may seem appetizing at the store but do not go down well or "sit" well on the road, especially if you allow yourself to become a hair dehydrated (which of course you shouldn't do, but it happens). A modest amount of salt is desired, but too much (without enough water) can send your stomach on a spin. (The nut-raisin snack, by itself, is just a tad "heavy" for my taste, and may be a hair too heavy in terms of fat. But as one of a small variety of snacks it's fine, and likely a decent source of salt.)
I would say figure on about 500 calories of mostly carb snacks for a 50-mile, 3-hour ride. This isn't nearly enough to replace the calories you burn, but it is enough to prevent a low blood sugar condition.
And, of course, HYDRATE!
Really, any source of food is fine for a 25–50 mile ride.
Although for anything of longer distance, you're going to want to add significant quantities of carbohydrates. Nuts are great, but they're primarily fat and protein. Toss some M&Ms and raisins into that mix for an improvement, and make sure there's some salt in them.
But really, 25–50 miles doesn't require any sort of well-tailored nutrition. Just bring water and any kind of tasty snacks and you'll be fine.