Animal Products Technology (Milk, Meat, Wool, and By-products)
Animal Products Technology (Milk, Meat, Wool, and By-products) tests composition, preservation and quality. Expect calculations on standardization and questions on why milk or meat spoils.
Core rules
- Cow milk contains roughly 87% water, 3.5–4.5% fat and 8.5–9% solids-not-fat; buffalo milk is richer in fat.
- Pasteurization uses 63°C for 30 minutes (holder method) or 72°C for 15 seconds (HTST), followed by rapid cooling. It kills pathogens but is not sterilization.
- Clean milk depends on healthy animals, clean utensils, rapid chilling and avoiding antibiotic residues.
- Meat quality is affected by ante-mortem stress, rigor mortis, chilling and hygiene. Meat inspection removes diseased or contaminated carcasses.
- Wool is keratin; quality depends on fibre diameter, staple length, crimp and cleanliness. By-products include hides, bones, blood meal, tallow and manure.
Worked example
Standardize 100 kg of 4% fat milk to 3% fat using skim milk (assume 0.05% fat). Let x be skim milk added. Fat balance: 100 × 4 = 3 × (100 + x). 400 = 300 + 3x, so x = 33.3 kg. The final mix is about 133.3 kg at 3% fat. The reasoning balances fat, not total weight.
Traps
Do not call pasteurization sterilization. Do not standardize by adding water. Do not judge meat only by colour. Do not store warm milk in the same tank as chilled milk.