2009-4-12 17:11
magiyafeimo
俾少少資料你先
如果牛奶過期，會變質，結塊
結塊的話，黏稠度增加
有專門測試黏稠度的機器，用一支攪拌棒係中間轉動，以轉動時遇到既阻力黎知道佢既黏稠度viscocity
2009-4-14 15:05
ZeroYip
我唔係好明個問題
仲有係咩功課?
If you want to test the milk expire or not
you may use the pH paper to test also.
Normaly fresh milk is around 6.4-6.7 pH
and when time pass by @ room temperature
The lactose in the milk is converted to lactic acid
such that the concentration of H3O+ ion increase
as a result the pH decrease.