Nutrition Diva's Quick Tip for storing oils properly to prevent spoiling
Nut and seed oils, including walnut, sesame, grapeseed, sunflower, and flaxseed, are best stored in the refrigerator. These highly unsaturated oils are particularly vulnerable to spoiling, or becoming rancid. Storing them in the fridge protects their flavor and extends their shelf life. Olive and canola oils are more stable and can be stored at room temperature -- a cool dark cupboard is best. Rancid oils are not only bad-tasting, they are harmful to your health, so discard any oils that smell "off."
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