Kidney

How to serve kidney by age

6 months+

Blended smooth or very finely minced into other food

Simmer or braise trimmed lamb, veal or beef kidney until it's cooked all the way through (160°F / 71°C), then blend it smooth with a little cooking liquid, breast milk or formula, or mince it very finely. Stir a teaspoon or two into mashed potato, vegetables or a soft meat sauce. Cooked kidney is springy, so it isn't offered as finger strips at this age.

Size

A teaspoon or two, blended smooth or very finely minced and stirred into mash or a soft sauce.

Check before serving

Check the thickest piece with a food thermometer (160°F / 71°C) before blending. Rub a little of the mix between your fingers: there should be no springy lumps.

US and UK advice differ here. The AAP suggests mashed food or soft pieces no larger than ½ inch; the NHS suggests soft finger-sized pieces your baby can hold in their fist. Both agree the food must squash easily.

9 months+

Finely minced, mixed into soft food

Stir a teaspoon or two of very finely minced cooked kidney into ground meat, rice, pasta sauce or mashed vegetables, or keep offering it blended.

Size

Finely minced into tiny bits much smaller than about 1 cm (just under ½ inch), stirred into soft food.

Check before serving

Squash a piece between your thumb and finger. If it springs back, mince it finer or blend it.

12 months+

Finely chopped into family dishes

Chop cooked kidney finely into a beef stew, cottage pie or bolognese, about a tablespoon for your toddler. Take their portion out before adding salt, stock cubes or gravy.

Size

Finely chopped pieces about 1 cm (just under ½ inch) or smaller, mixed into a dish.

Check before serving

Each piece should squash easily between your thumb and finger. Chop firm or rubbery bits finer.

18 months+

Mixed into family meals

Serve kidney finely chopped in family stews and pies cooked until tender. Avoid larger pieces: kidney stays chewy even when it's well cooked.

Size

Finely chopped pieces smaller than about 1 cm (just under ½ inch), mixed into a soft dish.

Check before serving

Still check that pieces are small and soft, not chewy chunks.

Always have your child sit upright in a high chair or at the table, and stay with them the whole time they eat. Keep to the size and texture for their stage. Every baby develops on their own timeline.

How to prepare kidney

1. 1

   Buy fresh lamb, veal or beef kidney from a butcher or shop. There's no need to rinse it: the NHS says washing raw meat splashes bacteria onto surfaces. Keep it away from ready-to-eat food, and wash your hands, board and knife after handling it.

2. 2

   Peel off any thin outer membrane, cut the kidney in half and snip out the white core and any fat with clean scissors.

3. 3

   Simmer or braise the pieces in water or unsalted liquid until cooked all the way through. USDA FSIS says to cook organ meats, including kidney, to 160°F (71°C), checked with a food thermometer, and the NHS says to cook offal until no pink is left. Don't add salt or stock cubes.

4. 4

   Let it cool, then blend it smooth with a little cooking liquid, breast milk or formula, or mince it very finely. Freeze small portions you won't use within a day.

How much to offer

Start with a teaspoon or two of blended or finely minced kidney stirred into a food your baby already eats. Kidney is very rich in selenium: FoodData Central lists about 219 mcg per 100 g of cooked lamb kidney and 168 mcg for beef kidney, so a tablespoon (about 15 g) of lamb kidney has about 33 mcg. NIH sets daily upper limits of 45 mcg up to 6 months, 60 mcg at 7 to 12 months and 90 mcg at 1 to 3 years, counting all food and drink together, and milk and other foods add selenium too. So we suggest about a teaspoon or two at a time for babies and about a tablespoon for toddlers. That is our suggestion, worked out from these figures: no official source gives a portion for kidney. Your baby decides how much to eat from the small portion you offer.

Common mistakes

Questions parents ask

If your baby refuses kidney

• Many babies need 10 or more tries before they accept a new food. Keep offering it alongside foods they already like.
• Kidney has a strong taste. Mix a small amount into foods your baby already likes, such as mashed potato or a beef and vegetable stew.
• Moisten it with a little of its cooking liquid, breast milk or formula.
• It's fine if kidney isn't a favorite. Meat, beans, lentils and iron-fortified cereal are iron-rich too.

Never force or pressure your baby to eat. Some days they'll eat more, some days less, and that's normal.

Buying and storing kidney

• Keep raw kidney in a sealed container on the bottom shelf of the fridge, and cook or freeze it within 1 to 2 days.
• Cooked kidney keeps for 3 to 4 days in a covered container in the fridge. Blended kidney keeps for 1 day. Rice dishes are the exception: cool them within 1 hour, keep them in the fridge for no more than 1 day, and reheat them only once.
• Freeze blended kidney in small portions (an ice cube tray works well) for 1 to 2 months (FDA), and cooked kidney stews for 2 to 3 months. Thaw in the fridge and use within 24 hours of thawing. Reheat only once, to 165°F (74°C), until steaming hot, then let it cool before serving.
• Throw away any food left out at room temperature for more than 2 hours (1 hour if it's hotter than 90°F / 32°C).