The Beech-Nut Nutrition Corp. has developed the following guidelines for heating baby dinners and vegetables in the microwave:

- Make sure the pop-top, quality seal cap pops when you first open the jar so that you know the food is safe.- Remove the metal cap. Cover the jar with plastic wrap.

- For smaller, 4 1/2-ounce jars of baby food, cook for 15 seconds at medium (50 percent power). For larger, 6- or 7 1/2-ounce jars, cook for 30 seconds at medium (50 percent power). If you microwave longer than these recommended times, the food might become hot enough to scald the baby's mouth and throat.

- Always mix the food after warming. One part of the food can be very hot and another part very cool. Mixing evens out the temperatures.

- Taste the food yourself to make sure the food is not too warm. Use a different spoon to feed the baby.

- Do not feed the baby with food taken directly from the jar; spoon the baby food into a dish before feeding. Why? The food can get watery. Beech-Nut products are made without modified starch and are highly digestible, to match a baby's digestive system. Products like Beech-Nut baby food that have no modified starch can get very watery because the enzymes from saliva start to digest the food.

- Do not spoon uneaten food back into the jar. Again, enzymes from the baby's saliva can get into the untouched food and make it watery.

Beech-Nut does not recommend warming baby meats in the microwave. The company says these foods are very thick, can easily overheat.