liquor expense

You may claim as a business promotion expense. But see to that it does not exceed 20,000 at a time for a bill.

The income tax is not defined that the liquor expenses are not good for health

they are only defined that the expenses which are paid in cash is not more than 20,000/- in one day to one person and which are allowed for business purpose are also allowed 

you can claim liquor  expenses for business purpose or promotion 

that's why you can claim