Regarding 30 seconds - u can dip it for 30 seconds when the hygiene standards are high - i mean everything the butcher's knife to the slaughter table has been thoroughly cleaned (Gore people are very particular about that) we only read it and can not follow them with closed eyes. what are the hygiene standards in India? ZERO. for that matter - keep it for five minutes or a little longer.
Yes, liver can be fed but not everyday. say once a while.