Spoon a portion into a glass dish to warm it, stir, let it stand 30 seconds and test before feeding. Thaw frozen jars in the fridge first, and leave a little space at the top before freezing. The metals in baby food come from the food itself, and homemade isn’t automatically lower, so whether you make it or buy it, rotate foods through the week.
Weck 751 glass jars with glass lids, 200 ml, 12-pack: Glass jar and glass lid. The seal ring is rubber, held with steel clips; check what's in the box, as rings and clips are sometimes sold separately. All-glass jars cost about three times as much as jars with plastic lids.