Cider Final Filters
Final filtration helps ensure the removal of cider spoilage organisms that can cause refermentation, off flavors or turbidity post bottling. Yeasts, lactic bacteria and acetic bacteria are typical cider spoilage organisms.
Since cider final filters are the last filtration step prior to bottling they are therefore the most critical filtration step. Cider final filtration assures clarity and brightness, and helps ultimately ensure brand protection.
Cider final filters are often described by their pore size, 0.45 µm or 0.65 µm. Because the pore size does not indicate the reduction of microorganisms, a final filter should be validated for its bacteria and yeast reduction by cider specific microorganisms.
The term used to describe this retention is LRV (Log Reduction Value). The difference between log retention values is shown in the table below.
Cider final filters should also be integrity testable. The integrity test as a non-destructive test is linked to the performance of the filter and as such makes sure the filter is working as expected in the application.