The presence of lipases was observed in three byproducts of orange juice processing: peel, core and frit.
The enzymes were characterised biochemically over a wide pH range from neutral (6–7) to alkaline (8–9).
The optimal temperature for the activity of these byproducts showed wide range at 20 C to 70 C, indicating
fairly high thermostability. The activities were monitored on p-NP-butyrate, p-NP-laurate and
p-NP-palmitate. For the first time, lipase activity was detected in these residues, reaching 68.5
lipase U/g for the crude extract from fractions called frit.
2