EXTRACTS OF JAPANESE QUINCE SEEDS - POTENTIAL SOURCE OF ANTIOXIDANTS

Japanese quince ( Chaenomeles japonica ) is a minor fruit crop in Latvia and Lithuania; it is used for production of juice, aroma and fruit fibers. The seeds are by- products of food processing that could be used furt her for different purposes. The seeds of Japanese quince co ntain about 10 to 20% of oil. The composition of th is oil is quite unique: nearly 90% of it is formed by two fat ty acids - linoleic (52.4%) and oleic (35.6%). We h ave also found out that the extracts of Japanese quince seed s can be used to improve stability of vegetable oil s ‐ 10 wt-% additive of ground seeds to hempseed oil and 5 wt-% additive to rapeseed oil can increase the oxidativ e stability of these oils about 2.0 and 1.6 times, respectively . Unfortunately, the seeds of Japanese quince conta in also amygdalin ‐ toxic cianogenic glycoside. Due to this compound the usage of seeds of Japanese quince are very limited, especially in case of their hydrophilic ex tracts. Our research was focused on hydrophilic ext racts of seeds in order to find out both the best method to prepare polyphenols rich extracts, as well as to de termine the amount of toxic amygdalin in the ethanol/water extr acts of seeds and in the extracted seeds. We have f ound out that the largest amount of total polyphenols can be obtained when whole seeds are extracted with the mixture of ethanol and water under reflux.