Relationship of Soluble Solids, Alcohol-insoluble Solids, Fruit Calcium, and Pectin Levels to Firmness and Surface Pitting in ‘Lambert’ and ‘Bing’ Sweet Cherry Fruit1

Abstract

Abstract Firmer ‘Lambert’ and ‘Bing’ sweet cherry fruit (Prunus avium L.) was associated with higher soluble solids (SS), higher concentration of alcohol-insoluble solids (AIS), and pectinase-soluble pectic substances and less crop, surface pitting, and lower concentration of water-soluble pectic substances. Fruit Ca and ethylene diamine-tetraacetic acid (EDTA) soluble pectic substances were not associated with fruit firmness. Total pectic substances were lower in AIS extracted with 70% ethanol held at 70°C for 1 hour as compared with AIS extracted with 70% ethanol at room temperature plus 80% ethanol in 5% HCI (v/v) for an additional hour. The major differences between the 2 methods were less EDTA and more pectinase pectins in 70°C ethanol-extracted AIS.