YSK in the US foods can be listed as TRANS FAT FREE and containing 0g trans fat and STILL CONTAIN TRANS FAT. If you see the word hydrogenated or partially hydroganted oils under ingredients, it contains trans fat.
from /r/YouShouldKnow
在美国，YSK的食品可以被列为不含反式脂肪，并含有0克反式脂肪，但仍然含有反式脂肪。如果你看到成分下有氢化油或部分氢化油的字样，则含有反式脂肪。