Gastrointestinal samples from six 1-year abalone and three 2-year
old abalone, per treatment replicate were partially thawed, weighed,
pooled and homogenised in four volumes of distilled water (W/V)
using a Dounce homogeniser. As each enzyme kit had set pH levels,
the homogenate was resuspended in four volumes of buffer, supplied
with each kit (V/V). The suspensions were centrifuged at an acceleration of 17,530 g for 20 min at 4 °C. The resulting supernatants were
analysed in triplicate for trypsin, α-amylase and lipase activity at the
corresponding temperature at which abalone had been held (i.e. 14,
18 or 22 °C) using spectrophotometric techniques and commercial enzyme test kits. Enzyme activities were measured in the linear reaction
phase. Each speci fic enzyme kit included internal standard solutions