Analysis and modeling of browning of the Granny Smith apple during drying

• Published in: Drying technology Vol. 15; no. 10; pp. 2587 - 2596
• Main Authors: Voegel-Turenne, C. (Universite de Technologie de Compiegne, France.), Allaf, K, Bouvier, J.M
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 01-01-1997
• Subjects: apple; APPLES; BROWNING; BRUNISSEMENT; discolouration; DRYING; KINETICS; MANZANA; OSCURECIMIENTO; POMME; SECADO; SECHAGE; thermic degradation
• ISSN: 0737-3937; 1532-2300
• DOI: 10.1080/07373939708917379

After proposing simple empirical models for drying kinetics and for sorption isotherms, the authors show that browning during drying of Granny-Smith apple samples can be calculated from models developped in static conditions. The time at which the browning begins (t
B
) is similar to the induction time deduced from the static conditions ; it corresponds to a very low sample water content (around 1% dry basis) and to a sample temperature equal to the heating temperature. The "thermic past" (drying method, drying rate, heating temperature before t
B
) has no influence on the browning rate, only the heating temperature after t
B
is important