We are all familiar with the saying “don’t cry over spilt milk,” but what about spoiled milk? Discovering that your milk has gone bad can be frustrating and upsetting. Many people use milk daily without fully understanding what causes it to spoil.
The key factor leading to milk spoilage is the multiplication of bacteria present in the milk. This bacterial growth converts lactose (milk sugar) into lactic acid, resulting in a sour taste and the formation of clumped proteins, giving the milk a thick, lumpy texture.
While it is inevitable for milk to eventually spoil, there are ways to prolong its freshness. Avoid introducing new bacteria into the milk by refraining from drinking directly from the bottle. Keeping the milk consistently chilled is crucial, as bacteria multiply more rapidly above 4°C.
The shelf life of milk depends on the type of milk and how it is handled. Pasteurised milk, the most common type in the UK, undergoes a process where it is heated and rapidly cooled, extending its shelf life to up to 10 days unopened and three to seven days once opened.
Various milk alternatives, such as oat milk, have different shelf lives. Refrigerated oat milk can last 7-14 days unopened and 5-7 days once opened, while UHT oat milk lasts longer unopened but should be consumed within 7-10 days after opening.
Filtered milk, like Arla Cravendale, undergoes extra filtration to remove more bacteria, significantly extending its shelf life to seven days after opening and 21 days unopened. UHT milk, heated to high temperatures, can last up to six to nine months unopened and 7-10 days once opened.
Proper storage is crucial for maintaining milk freshness. Keeping the fridge at around 2-3°C and storing milk towards the back, away from warmer areas like the fridge door, can help preserve its quality. Filtered milk like Arla Cravendale stays fresh longer due to the thorough filtration process and opaque packaging that protects it from light exposure.
Check the milk’s freshness by smelling it for neutrality, looking for unusual textures, conducting a hot water test for curdling, and tasting a small amount. These simple steps can help determine if the milk is still good to consume.
