Comparison of volatiles of banana powder dehydrated by vacuum belt drying, freeze-drying and air-drying

Banana puree was dehydrated by using three different drying methods: vacuum belt drying (VBD), freeze-drying (FD) and air-drying (AD) to produce banana powder. Volatiles were extracted from dried banana powder with solid phase micro-extraction (SPME), and separated and identified by gas chromatography-mass spectrometry (GC-MS). SAS (statistical analysis system) was used to evaluate the contribution of the main volatiles. Esters play the most important role in banana powder aroma. The main components detected in banana powder which are responsible for its fruity odor were 3-methylbutanoic acid 3-methylbutyl ester, 3-methylbutyl acetate and butanoic acid 3-methylbutyl ester. Most of the alcohols identified in banana powder were enols and some were of the long chain type. Eugenol and elemicin which give the product its typical mellow aromas were also identified. Alkyls, alkene and alkyne constituted the minor components in banana powder. Basing on the principal component analysis of statistical analysis system, it can be inferred that the preferred method for producing banana powder with the optimum aroma is FD, followed by VBD and then AD. (c) 2007 Elsevier Ltd. All rights reserved.