Optimization of Extraction Conditions via Single Factor Experimentation
The conditions of aqueous extraction were optimized via single factor experimentation under the condition of that the general procedure just mentioned above in “2.2.1. ” was followed, using OR as an indicator. All the extraction conditions studied are indicated in Table 1.
The oil content of de-oiled pecan meal vacuum-dried to the constant weight at 50 ℃ was measured according to the Soxhlet method (Chinese National Standard, 2008). The calculation of OR was carried out according to follows:
OR (%) = (X1-X2)/X1× 100%
In this formula, X1 (g) means quantity of crude oils extracted from the pecan kernel slurry (i.e. 10.00 g × fraction of crude oil from the pecan kernel slurry (dry basis)), while X2(g) means quantity of crude oil remaining in the de-oiled pecan meal (i.e. amount of de-oiled pecan meal (g, dry basis) × its fraction of oil).