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While lemon juice's high acid content makes it a natural preservative, leaving it unrefrigerated after opening can affect its quality, taste and safety. Following proper food safety guidelines is key to preventing illness and improving the overall quality of your food.

Identifying Spoiled Lemon Juice

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Lemon juice that has been left out for a long period can alter in color, turning a slightly darker shade of yellow, or become cloudy. Unrefrigerated lemon juice can also alter in smell and taste, and may not be as effective as a food preservative or flavor additive.

Average Shelf Life of Lemon Juice

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Lemon juice can last for up to 12 to 15 months if left unopened in the pantry. Once opened, if refrigerated, lemon juice can last for up to six months. It is important to keep the lemon juice in the original tinted bottle, as light can be damaging. Concentrated lemon juices typically last longer than fresh squeezed due to the addition of extra preservatives.

Uses for Lemon Juice

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Lemon juice can be used in the preservation of fruits and vegetables, or in the making of jams and preserves. Lemon juice is also effective as a cleaning agent, beauty product and diuretic. Be sure to check the expiration date and contents before using lemon juice for any purpose.