If you look at page source and it's "right", then Google will get it "right" sometime when they come visit again.
If it's not "right", then yes, you've likely got something breaking the normal functionality. In that case, you'll need to describe everything that makes your site different from a brand new untouched install. What version of Zen Cart, what addons have you installed, what switches have you changed in the admin and why, etc. Does it happen on all products or just some? If you create a brand new product, does it happen to it too? What are all the settings you've set on the metatags page for that product?
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