Sardines identification method
Before opening the identification of main basis to see container appearance, hand pinched by the tank cover, banging on listening and leak test four aspects, specifically:
First, to see identification method. Mainly check whether canned sealing closely, appearance is clean, for wear and corrosion situation, such as appearance filth, dim, the spot, edge rust, etc. Cans, glass bottle, can be placed directly observe its internal quality situation, where the bright gently shake after neat to see if the content block, whether liquid turbidity, presence of foreign impurities, etc.
Second, hand knead identification method. The main check can swell phenomenon. Finger press tinplate cans base and cover are available, and canned bottle pressure cap, look carefully for the bilge tank.
Third, listen to identification method. Mainly used to check the quality of canned contents, can use sticks or finger tapping bottom cover of the tin centre, listen to the sound to identify the quality of canned. Good quality canned voice is ringing, the flatness; Quality and inferior canned including contents, gap big voice, turbidity, the sound, the raucousness of "old".
Fourth, the identification method of leak. Whether can leak, canned for preservation is very important. During the leak test, are generally will squash with the hand can sink into the water at the bottom, if you have a flat place will find small bubbles. But check the canned submerged in the water don't move, so as to avoid small bubbles can't see it clearly.