How can a cup of milk pick a good quality?

Update:09 Oct 2017
Summary:

   Milk cup at the bottom of the cup can not be printed […]

   Milk cup at the bottom of the cup can not be printed, because the bottom of the cup there are printed patterns, but also easy to rub the color to the other side of the cup, then, how can we pick a good quality milk cup?
   1. look outside the packaging. Carefully check whether the packaging marked "product name, factory name, site, product implementation standards, production date, shelf life, health permit" and other countries must be marked content, if the content is incomplete or not standardized, it is best not to buy.
   2. look at the cup body. Good quality milk cup cup body color should be uniform, the color should not be too bright, clear outline, wax layer thickness uniform, facing the light to see, the cup body without impurities, bubbles, water lines, lumps and so on.
   3. Look at the cup. Note cups smooth, smooth, no waste side, burr, cup should not have obvious depression, wrinkling.
   4. smell the smell. Smell the milk cup has no pungent smell, especially the taste of ink.
   Pinch Can be hand on both sides of the cup gently squeeze, good milk cup is very hard, resilient, poor quality milk cups are often pinch after the very soft, no rebound performance, pinch on the flat.
   Finally, when using the milk cup, do not drink the first glass of water. First with hot water about once, four or five minutes after the water drained, so that milk cups of harmful substances fully volatile. Overcooled or overheated water, alcoholic or acidic beverages are not suitable for disposable milk cups.

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