Characterization of juice in fruits of different Chaenomeles species

The juice in fruits of 21 genotypes of Japanese quince (Chaenomeles japonica), I genotype of Chinese quince (C cathayensis), I genotype of flowering quince (C speciosa) and I genotype of a hybrid taxon (C x superba), representing plant breeding material, was extracted and characterized. The content of juice in the fruits varied between 41% and 52%, on fresh weight basis. The juice was very acidic (pH 2.6 and a titratable acidity of 3.5 % calculated as anhydrous citric acid, on average) and transparent (52 NTU, on average), with low density and viscosity. The content of soluble solids was also low (7.1degreesBrix, on average). Proteins constituted 26 mg/100 ml juice on average, but no soluble polysaccharides were present. A high content of vitamin C (59 mg/100 in] juice, on average) and phenols (284 mg/100 ml juice, on average), beside the high acidity of the juice, suggests that chaenomeles juice may be an interesting raw material as ingredient for the food industry and a source of valuable substances. A principal components analysis separated the Japanese quince genotypes from the other genotypes studied, thus indicating a clear difference in the characteristics and chemical composition of the juice. (C) 2003 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.