To salt or not salt broth for use in recipes?

It depends upon how much you expect the broth to be reduced while making the dish, and how salty the other ingredients in the dish are. Risotto is a good example of a dish that should be made with a broth less salty than would be ideal for just drinking. The broth will be reduced significantly while making the risotto (so the salt will become more concentrated). Plus, most risotto recipes call for parmesan, which is salty. You want some salt in the broth because the rice will be better if it absorbs some salt, adding salt at the end with the parmesan can't make up for the rice being made without any salt.

In most cases, it's best to salt broth minimally for cooking. In other words, use enough salt so that the broth isn't terribly bland when tasted alone, but less salt than you would want in chicken noodle soup.

Canned "reduced sodium" broth hits that pretty well, although it can still be somewhat too salty for some applications. The most well known brand in the USA of reduced sodium chicken broth is Swanson. It contains 570mg of sodium per 1 cup of broth. So, every cup of that broth contains 1.4 grams of salt (salt is 40% sodium by weight). So, if you make broth that you might use in a number of different ways, I would recommend about 1 gram of salt per cup of broth. That's enough salt to permeate starchy ingredients without fear of broth reduction making the final dish too salty.

After that, just salt to taste at the end.

Old question, but anyway... I hope it is useful to someone

My understanding is that the flavors of meat and vegetables pass better to unsalted water. So, if you are keeping only the broth, it is better not to salt it. If you are eating some of the vegetables, meat or fish and you don't salt the water, they will be tasteless. On another hand, if you salt the broth, later is difficult to know how much salt contains your recipe.

When I cook, I estimate the serves that I am getting and I use a level teaspoon salt every two serves. So, I never salt the broth broth. I make the broth and I freeze it in portions. When I use a portion of broth on a particular recipe, I salt all together based on the number of serves I am getting.

Despite not salting the water, I eat the meat or fish and carrots. Cook the carrots in one piece and the vegetables that you are going to waste in tiny pieces (I use the mincer). This way you increase the surface contact between the vegetables (except carrots or other you like) and the water and they should release better their flavor. You also reduce the cooking time.

I wouldn't add salt and broth. For risotto, just the broth. You can always add more salt after the dish is prepared, if when tasting it you think it needs more. Sauerkraut and some cured meats are made with a large amount of salt, for preservative purposes. Using the risotto example, salt basically just adds flavor.