Freeze-dried uses freezing plus vacuum sublimation to dehydrate, with moisture around 3-6%; it retains nutrients best but needs rehydration. Air-dried uses low-temperature long drying, with moisture around 12-14%; it is ready to feed from the bag and has a jerky-like texture. Both cost 2-4 times more per kg than dry food, but do not require refrigeration. Note: freeze-dried/air-dried does not equal sterilised; after handling raw-meat products, wash hands and clean utensils.
3 Key Points
- Process determines moisture and texture: freeze-dried 3-6% (needs rehydration), air-dried 12-14% (can feed directly), general dehydrated food about 10-14%.
- Price per kg ranking: freeze-dried ≈ air-dried > freeze-dried mixed with dry > general dry food. Per kg, the difference can be 4-10 times.
- Safety cannot be ignored: FDA tested 196 raw meat pet food samples; 15 tested positive for Salmonella, 32 for Listeria. Freeze-drying does not kill pathogens, so handle as raw meat.
Comparison of Three Processes
| Item | Freeze-Dried (lyophilisation) | Air-Dried (low-temperature air drying) | General Dehydrated |
|---|---|---|---|
| Principle | Freeze first, then vacuum so ice sublimates directly | Long drying at 25-70°C | Medium-low temperature hot air dehydration |
| Finished moisture | About 3-6% | About 12-14% | About 10-14% |
| Nutrient retention | Closest to raw ingredients (low temperature, no liquid water) | Good, some vitamins affected by heat | Average |
| Feeding | Needs rehydration (mostly 1:1 to 1:3) or dry feeding | Can feed directly, can add water | Can feed directly |
| Hong Kong price (per kg) | $320-778/kg | $288-349/kg | $160-420/kg |
| Storage | Room temperature sealed, away from light; protect from moisture after opening | Same | Same |
Real Hong Kong Prices and Daily Cost (checked 2026-10-02)
| Product | Type | Net Weight | Hong Kong Price | Price per kg | Daily Cost (250 kcal estimate) |
|---|---|---|---|---|---|
| ZiwiPeak Steam-Dried Wild South Pacific Fish 2.2kg | Air-dried | 2.2kg | $652 | $296/kg | Labelled 4,400 kcal/kg → about $17/day |
| ZiwiPeak Steam-Dried Free-Range Chicken with Whole Mackerel 800g | Air-dried | 800g | $279 | $349/kg | Not labelled on packaging, cannot calculate |
| ZiwiPeak Air-Dried Mackerel and Lamb 1kg (discontinued) | Air-dried | 1kg | $288 | $288/kg | Not labelled on packaging, cannot calculate |
| ZiwiPeak Steam-Dried Kitten Recipe 700g | Air-dried | 700g | $279 | $399/kg | Not labelled on packaging, cannot calculate |
| Instinct Raw Freeze-Dried Kitten Food Free-Range Chicken 9.5oz (discontinued) | Freeze-dried | 269g | $86 | $320/kg | Packaging states 6% moisture, 38% protein |
| PetChill Banquet All-Life-Stage Cat Raw Freeze-Dried Food Chicken + Turkey 500g | Freeze-dried | 500g | $257 | $514/kg | Not labelled on packaging, cannot calculate |
| PetChill Banquet Senior Cat Raw Freeze-Dried Food Muscle & Joint Care 500g | Freeze-dried | 500g | $292 | $584/kg | Not labelled on packaging, cannot calculate |
| Absolute Bites Freeze-Dried Fresh Meat Bites Salmon 280g | Freeze-dried | 280g | $217.8 | $778/kg | Not labelled on packaging, cannot calculate |
| Frontier Freeze-Dried Cat Food Hypoallergenic Single Protein Free-Range Chicken 300g | Freeze-dried | 300g | $228 | $760/kg | Not labelled on packaging, cannot calculate |
| Nulo Grain-Free Freeze-Dried Cat Food Chicken + Salmon 16oz | Freeze-dried | 454g | $499 | $1,099/kg | Not labelled on packaging, cannot calculate |
| Primal KIBBLE Raw Coarse Grind Freeze-Dried Cat Food Chicken 1.5lb | Freeze-dried mixed | 680g | $420 | $618/kg | Not labelled on packaging, cannot calculate |
Comparison: General large-bag dry food costs $57-90 per kg (e.g. ProSeries Weight Control Senior Cat 5.8kg $310 = $53/kg), air-dried about $288-399/kg, freeze-dried $320-1,099/kg. That means feeding exclusively freeze-dried costs about 5-15 times that of dry food.
Rehydration Ratio and Feeding Methods
| Form | Suggested Method | Notes |
|---|---|---|
| Freeze-dried (complete) | Add water per packaging instructions (commonly 1:1 to 1:3, i.e. 10g freeze-dried with 10-30 ml water), wait 3-5 minutes for full absorption | Do not feed dry only: complete freeze-dried foods mostly calculate moisture and calories in rehydrated form |
| Air-dried | Can feed directly; also recommend placing a water bowl nearby or adding 1-2 tablespoons of water | Texture is hard; watch for older cats with poor teeth |
| Freeze-dried mixed | Sprinkle as a topper on dry food or canned food | This is partial replacement; deduct from main food portion when calculating calories |
Hong Kong weather practicalities: After opening, seal and add a desiccant; finish within one month (freeze-dried softens and spoils easily after absorbing moisture). Do not store near the kitchen stove; consume within 30 minutes after rehydration and discard leftovers.
Safety Points for Raw-Meat Products (Do Not Feed Casually as Treats)
FDA laboratories tested 196 raw meat pet food samples; 15 tested positive for Salmonella, 32 for Listeria monocytogenes. Studies also show that households feeding raw meat diets have a higher risk of human infection (especially young children, the elderly and immunocompromised individuals).
Handling principles:
- Use separate utensils (do not wash with human dishes)
- Wash hands with soap for 20 seconds after handling freeze-dried/raw meat
- Clean countertops and cutting boards with hot water and detergent
- Seal after opening to avoid cross-contamination with other foods
- If there are young children or immunocompromised members at home, consider consulting a veterinarian before deciding to feed raw-meat products
Which Cats Suit Freeze-Dried/Air-Dried?
| Situation | Recommendation |
|---|---|
| Want to increase meat content, reduce carbs | Air-dried or freeze-dried mixed (20-30% ratio) offers the best value |
| Picky cats, need to enhance aroma | Freeze-dried as a topper (3-5 g per meal is already very aromatic) |
| Older cats with poor teeth | Freeze-dried rehydrated to a pate consistency is easiest to eat |
| Limited budget | Large-bag freeze-dried mixed + complete wet food saves more than half compared to all freeze-dried |
| Kidney disease/urinary history | Must first confirm phosphorus content and calorie density with a veterinarian before deciding |
Sources
- FDA (US Food and Drug Administration) raw meat pet food safety study: of 196 raw meat pet food samples, 15 tested positive for Salmonella, 32 for Listeria.
- AAFCO cat food nutritional standards: adult maintenance minimum crude protein 26% dry matter basis, growth stage 30%; taurine dry food 0.10%, canned 0.20% dry matter basis — used to determine whether a product is a complete food.
- NRC (National Research Council) 2006: recommended total daily water intake for cats 50-60 ml/kg body weight.
- Product moisture, protein, calories, price, net weight: PetChill product page packaging labels (checked 2026-10-02).
This article is general nutrition and safety information and does not constitute veterinary diagnosis or prescription. Please pay attention to personal hygiene when handling raw-meat products.
Further Reading
- Which Hong Kong cat food is good? 2026 Top 10 Popular Cat Food Brands Guide →
- Canned Cat Food vs Dry Food: Moisture Content, Water Intake and Daily Cost →
- Freeze-Dried vs Air-Dried: Process, Rehydration and Daily Cost →
- How to Tell Complete Wet Food from Complementary Wet Food? Label Identification →
- Phosphorus and Kidneys: mg/100kcal Comparison and Prescription Food Selection →
- 12 Popular Cat Foods Recommended by Scenario (Hong Kong Real Prices) →
⚠️ Some products mentioned in this article are discontinued (marked 'discontinued'); the prices are pre-discontinuation records. For other products, please refer to the current prices displayed on the online store.
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