Many years ago, I took a knife skills class at the Connecticut Culinary Institute. The class was great but I still do not chop correctly but I am much better with my chiffonade and julienne. One of the things the chef / instructor told us they do in the classroom is to save all of the end, peels and discards from the vegetables they are cooking with and throw them into freezer bags. When they have enough to fill a pot, they cover the vegetable scraps with water and simmer for several hours and voila homemade vegetable stock. Every since I took that class I have saved my veggie scraps. I use a gallon resealable freezer bag. When the bag is full, I throw the contents in a pot with water to cover on the stove or if I am going to work I use a crock pot. I use the stock to make soups and for cooking rice and pasta. I can not find the evidence but logic tells me that if I make a vegetable stock, there will be vitamins and nutrients in the stock that will seep into the pasta and rice (along with flavor) while cooking. If anyone has a reference to support my assumption I would greatly appreciate the reference. :)
Making veggie stock in this manner minimizes waste. The remains can still be composted since no protein is being added. Plus, it is always a surprise ... you never get the same flavor twice.Vegetables that I avoid are broccoli and cauliflower. Also be careful not to have too many greens (ie green beans, herbs) in the same batch. The broth starts tasting like a barn.