Anthocyanin in Freestone Peaches

Publisher Website
Google Scholar
Abstract
SUMMARY: Anthocyanin in freestone peaches was extracted, purified, and crystallized. The pigment was characterized by its absorption spectra in the visible and infrared region. Acid hydrolysis of the pigment yielded glucose and cyanidin, present in equal amount on a molar basis. No intermediate glycoside was found when the pigment was hydrolyzed under mild conditions, indicating a monoglycoside structure. Alkali degradation of the aglycone yielded phloroglucinol and protocatechuic acid, showing the presence of cyanidin in the pigment. The absorption peak of the pigment in a 0.01% methanolic HCl solution shifted from 525 to 568 mμ when aluminum chloride was added to form a chelate, indicating the presence of orthophenolic groups in the molecule. The peach anthocyanin is identified as a J‐mono‐glucoside of cyanidin. Variation in anthocyanin content between different varieties of California‐grown freestone peaches at various ripeness levels is presented. The importance of anthocyanin to discoloration in canned freestone peaches is discussed.