Using meat in stock results in a richer, more intense flavor and a cloudier broth compared to using just bones, which yields a lighter, cleaner flavor and clearer stock.
When making stock, the ingredients you use significantly impact the final product. Using meat, such as a whole chicken or meat scraps, introduces more protein and fat into the stock. As the stock simmers, these proteins break down, contributing to a fuller, meatier flavor. The fat emulsifies into the liquid, creating a richer mouthfeel and a cloudier appearance. This is because the proteins and fats are suspended in the liquid.
In contrast, using just bones, especially roasted bones, results in a lighter and cleaner-tasting stock. Bones primarily contribute collagen, which breaks down into gelatin during simmering. Gelatin adds body to the stock, but it doesn't impart as much intense flavor as meat does. Furthermore, a stock made primarily from bones tends to be clearer because there's less protein and fat to cloud the liquid. Roasting the bones beforehand adds depth of flavor through Maillard reaction, creating complex savory notes without the heaviness of meat.
If you're using meat in your stock and want to reduce the cloudiness, skim off any foam or impurities that rise to the surface during the simmering process. This foam contains proteins and fats that contribute to the cloudy appearance.