1, the colors are different. True laver is mostly purple-black after sun drying, and there is no fading phenomenon when touched by hand, while fake laver is a dyed purple-black substance with a particularly uniform color, but when touched by hand, there will be obvious color residue on the hand.

2. There are obvious differences after soaking in water. False laver will not only soften after soaking in water, but also change the color of water, while real laver will only soften and expand after soaking in water, and will not change the color of water.

True laver will turn green after roasting with fire, which is a bit like roasting seaweed. False laver will turn yellow after baking.

There are obvious differences in taste. Fake laver can't be chewed, but real laver can be chewed in your mouth.

5. There are obvious differences in volume. The volume of fake laver will not change obviously when it meets water, but the volume of real laver will expand rapidly after being absorbed, at this time, real laver will have obvious fishy smell, while fake laver has little taste or will emit some irritating chemical taste.

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