Note: before lunch tramp consumed the equivalent of six bottles (8)
I believe the answer is:
rehoboam
'equivalent of six bottles' is the definition.
The definition suggests a singular noun which matches the answer.
'note before lunch tramp consumed' is the wordplay.
'note' becomes 're' (as in do-re-mi).
'before lunch' becomes 'am' (I've seen this in other clues).
'tramp' becomes 'hobo' (both can mean a homeless person).
'consumed' is an insertion indicator.
're'+'am'='ream'
'ream' going around 'hobo' is 'REHOBOAM'.
'the' is the link.
Can you help me to learn more?
(Other definitions for rehoboam that I've seen before include "Large champagne bottle" , "Son of Solomon: wine bottle six times larger than normal" , "Very big wine-bottle" .)