In 2008, when Sanlu and its likes poisoned the nation with melamine-contaminated milk, they told us the "severe crackdown" would relieve us of all our worries.

Earlier this year, when we were taken aback by the re-emergence of melamine in dairy products packed in 2009 and subsequent cover-ups, we were promised an explanation, and told to "rest assured", because a "strict and thorough" cleansing was on its way.

We were even given reassurance that all the stock of melamine left by Sanlu and other dairy companies in 2008 had been destroyed.