What with cold, or temperature going up, producing lozenge (6)

'lozenge' is the definition.
(I know that troche is a type of lozenge)

'what with cold or temperature going up' is the wordplay.
'what' becomes 'eh' (sound used to ask 'what?' or 'pardon?').
'with' is a charade indicator (letters next to each other).
'cold' becomes 'c' (eg on taps).
'temperature' becomes 't' (abbreviation).
'going up' says the letters should be written backwards.
'eh'+'c'+'or'+'t'='ehcort'
'ehcort' written backwards gives 'TROCHE'.

'producing' is the link.