Im an avid Ketchup user. Im just so tired of turning up the bottle and getting a table spoon of vinegar on my plate before the real ketchup comes out. The only instructions on the bottle are: Shake well before first use, and For best results, refrigerate after opening. Shouldnt you shake well before every use? After the vinegar comes out of the Ketchup, it tends to change the flavor or the rest of the Ketchup. Im making reference to the Heinz Ketchup 36 oz side. Anything else is subpar. Enquiring minds want to know!