For cross‑border exported freeze‑dried pet‑food, microbial indicators are heavily checked by importers and customs. Vacuum freeze‑drying works under low‑temperature environment, but low‑temperature does not equal sterilization. If incoming raw‑materials carry high microbial load, freeze‑drying only puts microbes into dormant state. Micro‑organisms may revive and multiply under suitable later‑stage storage‑conditions and cause non‑conforming goods. Many factories mistakenly regard freeze‑drying as sterilization and suffer customs detention and goods‑return.
Raw‑material pretreatment forms first defensive‑line. Carry‑out incoming‑inspection for meat raw‑materials and control initial microbial count. Control workshop temperature during cutting‑processing and minimize meat room‑temperature exposure‑time to mitigate microbial reproduction. Regularly disinfect tools and conveyor belts to avoid secondary contamination.
Keep trays and turnover‑tools clean during tray‑loading. Operators shall follow clean‑workshop specifications to reduce human‑introduced pollution. Maintain reasonable material‑spreading‑thickness for sufficient dehydration in subsequent freeze‑drying cycles.
Focus on residual‑moisture end‑point control in freeze‑drying phase. Residual‑moisture is decisive for microbial revival and reproduction. Too‑high residual‑moisture enables micro‑organism revival even after freeze‑drying; excessive‑low moisture wastes production capacity. Set scientific residual‑moisture target for pet‑meat materials according to target shelf‑life.
Discharging and packaging are high‑risk stages. Freeze‑dried goods are dehydrated instead of sterilized. Maintain clean discharging‑environment and shorten open‑space exposure‑time; finish sealed‑packaging as quickly as possible.
Periodic equipment cleaning and disinfection cannot be omitted. Meat‑protein residues attached to chamber, cold‑trap and pipelines breed microbes and contaminate next‑batch materials. Establish fixed cleaning & disinfection SOP for chamber and racks after each batch or fixed cycles. Combine raw‑material management, workshop hygiene, freeze‑drying moisture‑end‑point control, discharging‑environment control and equipment disinfection to stably keep microbial indicators within export standards.
