‘Once opened, keep refrigerated and use within four weeks’

[BrotherMouzone]

Mobile Chicane said:

... the answer to the OPs question is to buy 1Kg bags of ginger, garlic and chillies from the 'ethnic' part of the freezer section at Asda.

These are frozen into single-use blocks and are ridiculously cheap compared with buying fresh.

Found them! Very convenient!