Purchased 4 litre bag of 3.25% milk from Costco, Ajax, Ontario on April 22, 2021. The use before date on both internal bags and tag was MA 08. Milk was kept in refrigerator with other foods. On May 01 poured milk into tea and it curdled. Also used milk to make porridge, which turned lumpy when heated. Thus threw bag of milk away. On May 02 opened another inside bag and poured into jug which was placed in microwave. The milk exploded and left a thick creamy slime on the inside of the microwave.