If bubbles appear on the surface of sesame paste, it means that water and other substances may be mixed. In this case, sesame paste may have deteriorated.

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2

If there are mildew spots on the surface of sesame paste, it means that there are mold microorganisms in it. In this case, sesame paste must have gone bad.

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three

If you can't judge clearly from the appearance, you can take a small part with a spoon and taste it. If the taste is obviously sour or has other peculiar smell, the sesame paste has also gone bad.

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four

Finally, sesame paste may agglomerate after a period of time. If it's just caking, none of the above conditions exist, and it's generally edible.