Comparative chemical composition of two Quercus species seeds growing in Tunisia

Abstract

The crude fat (7.2%, 5.6%), crude protein (3.71%, 2.9%), dietary fiber (2.6%, 2.7%) and total ash (2.19%, 2.47%) contents were determined for Quercus Ilex (Q.I) and Quercus coccifera (Q.C), respectively. The main fatty acids in acorn oils of quercus were oleic (54.77%, 49.88%), linoleic (23.04%, 28.25%), and palmitic acid (18.23%, 17.57%) in Q.I and Q.C species, respectively. The sterol composition for acorn oil Q.C was determined for the first time in this work. The contents of essential amino acids, in acorns of Q.I and Q.C were determined and some of them were within the FAO reference values. Acorn seeds were also a good source of K, P, Ca and Mg. The ethanolic extracts of acorns Q.I and Q.C were rich in phenolic compounds. The starch extracted from the seeds of acorns had a ratio between the contents of amylose and amylopectin 31/69, 36/64 for Q.I and Q.C, respectively. The current results show the potential of these two studied species of acorn and their uses as food resources.