Title: CAUSES OF BROWNING IN PEAR JUICE CONCENTRATE DURING STORAGE

Abstract approved: ri^r » . fe^i . ■ ^, * -Dr. RonaLd Wrolstad The causes of browning in pear juice concentrate (PJC) during storage were investigated. Two experiments were devised to assess the importance of oxidative and Maillard browning reactions in sam-ples of PJC stored at 370C. In addition, volatile analysis of certain stored samples was performed instrumentally and through taste panel evaluation. Color change in samples during storage was measured as increased absorbance at 420 nm, and as changes in Hunter L, a, b values. Pear juice and PJC (720Brix) produced commercially from d'Anjou pears were used to prepare samples. Treatments included removal of polyphenols with polyvinyl