Changes in anthocyanin concentration in Lychee (Litchi chinensis Sonn.) pericarp during maturation

Lychee has an edible aril surrounded by an anthocyanin-rich pericarp. Chemi cal and physical changes during lychee ripening were studied focusing on an thocyanins (Acy). Length increased up to the 17th week after anthesis (waa) , and width and weight increased continuously. Pericarp % decreased until t he 17th waa while aril % increased until the 19th waa. The fruit became dar ker during ripening and changed from light green to yellow-green (12-15th w aa), and from yellow-red to dark red (16-20th waa). pH decreased from 3.18 to 2.68 (12-15th waa), finally increasing to 4.49. Highest titratable acidi ty occurred in the 14th waa (4.44% malic acid) decreasing to a final 0.16%. Soluble solids were highest at ripeness (18 degrees Bx). Increases in mono meric (mAcy) and total Acy levels were observed up to the the 17th waa. Gre en fruits contained only malvinidin-3-acetylglucoside and polymeric pigment while the ripe fruit contained cyanidin-3-rutinoside (> 75%), cyanidin 3-g lucoside (< 17%) and malvinidin-3-acetylglucoside (< 9%). (C) 1999 Elsevier Science Ltd. All rights reserved.