Chemical composition and characterisation of seeds from two varieties (pure and hybrid) of Aesculus hippocastanum

Abstract

Investigations have been conducted on some samples of naturally desiccated horse-chestnuts ( Aesculus hippocastanum), representative of the two most common mediterranean varieties: the pure species (AHP, giving white flowers), and a hybrid (AHH, giving pink flowers). Different experimental techniques have been used to gain more information on morphological structure and chemical composition of these complex matrices. Surface analysis by SEM showed no differences in such floured samples (wild type), while thermal behaviour (DSC) outlines some significant differences between them. Chemical composition reveals some differences in residual moisture (AHP = 6.97%; AHH = 6.59%), proteins (AHP = 2.64%; AHH = 1.82%), lipids (AHP = 4.13%; AHH = 5.10%), glucides (AHP = 15.2%; AHH = 14.3%), and ashes (AHP = 2.51%; AHH = 2.19%). Most likely, these characters modulate other undifferentiated chemical parameters, such as cold water solubility (CWS:AHP = 53.9%; AHH = 48.6%), and total inorganic soluble salts (TISS:AHP = 2.18%; AHH = 1.92%). Principal component analysis was applied to differentiate the two horse-chestnuts varieties. In particular, the first principal component effectively distinguish and discriminates AHH and AHP samples in two well-separated categories, giving, at the same time, some information on the influence of the whole set of chemical compositional parameters.