From my experience, people who worry about food don't gain weight. If you worry if its grass fed organic beef, you won't eat enough. If you primary concern is that your chicken is free range happy chicken from happy farms you won't build muscle.  Unless you are a competitive athlete, worry about every bit of food you eat holds you back. Don’t think too much about it, just eat as much as you can afford.  Costco, Mandarin, and a freezer are your friends.