Here's What Happens When You Freeze Vegetable Cooking Oil - Tasting Table

"Here's what happens to oil when exposed to cold temperatures. To start with, oil doesn't freeze in one go the way water does. Instead, the bottle will gradually change, first becoming thicker and more viscous, then turning gel-like, and eventually solidifying. The temperature at which this happens depends on two factors: The balance of saturated and unsaturated fat in the oil, and the kind of processing it has undergone."

"Does freezing your oil make it go bad? No, it's completely OK to freeze your oil. In fact, most vegetable oils have naturally long shelf lives, anywhere from 12 to 18 months. Rather than suddenly expiring, they slowly lose freshness over time before eventually turning rancid. Cooler storage can help delay that process. In fact, straining and freezing it is one of the recommended ways to preserve used cooking oil for later."

"Understanding how different oils respond to different environments can help you make better choices about storage, shelf life, and even which oil to reach for when cooking. Oils rich in saturated fats solidify easily. Coconut oil, for example, starts solidifying at 75 degrees Fahrenheit (24 degrees Celsius). In contrast, oils with a higher proportion of unsaturated fats, like canola oil, need far lower temperatures, freezing only around 14 degrees Fahrenheit (-10 degrees Celsius)."

Freezing cooking oil does not spoil it and can help extend its shelf life by slowing the gradual loss of freshness that leads to rancidity. Oil thickens, becomes gel-like, and eventually solidifies as temperatures drop, rather than freezing abruptly like water. The temperature at which an oil changes state depends on its saturated versus unsaturated fat balance and on how the oil was processed. Most vegetable oils have long shelf lives of 12 to 18 months at room temperature, and cooler storage delays rancidity. Straining and freezing used cooking oil is a recommended preservation method. Blended oils show variable freezing behavior depending on their component oils.

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