Use a blunt knife and dry paper towel to remove the membrane from the ribs. Trim any excess on rib rack.
Apply yellow mustard to ribs, including underneath. Combine all dry rub ingredients in a small bowl. Apply liberally across rib rack. Leave to rest in refrigerator for 2 hours.
Fire up smoker to 225°F (107°C). If you are using a charcoal grill, set it up for 2-zone cooking.
Add wood chips to coals and place ribs on smoker grates. Close door or lid and smoke for 3 hours.
Remove ribs from smoker and place in foil pouch. Add apple juice. Wrap foil tightly.
Place wrapped ribs back in smoker. Smoke for a further 2 hours.
Remove ribs from smoker and foil pouch. Place ribs back in smoker and cook for a further hour, basting every 10 minutes with apple juice. Cook until rib temperature has reached 195°F.
Remove from smoker and allow to rest for 10 minutes. Slice and serve.