Can not.

Black goji berries put three or four years can not drink, black goji berries shelf life is generally 18 months, 3, 4 years is a little too long, if the bubble out of the water is brown indicates oxidation, has been moldy and deteriorated, it is recommended not to drink. The normal color of black goji berries is black or purple-black, if the bubble out of the black goji berries into brown, it is likely that the black goji berries have undergone qualitative changes, you can take a few bubble water, if the bubble water color is brown, brown-yellow, indicating that the black goji berries have been deteriorated.

Extended information:

Note:

With cold water or warm water (the temperature is too high will destroy the anthocyanins in the black goji berries, it is recommended that the temperature of 60 degrees or less warm water) brewing. When the nutrients and anthocyanins are released, part of the fruit will be slightly transparent white.

The reason why black goji berries change color when brewed in water is because the anthocyanins in black goji berries are dissolved in water. Anthocyanin is a kind of water-soluble pigment, and especially sensitive to acidity and alkalinity, with the environment of acidity and alkalinity and change different colors, black goji berries in alkaline water infiltration presents blue, in acidic water infiltration presents purple, so the black goji berries with tap water brewing will be blue, mineral water brewing is purple.

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