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Aseptically packaged guava puree in bag-in-box and guava
nectar base in Tetra Brik were produced in plant. These two
samples were stored under 5℃, 20℃ and 35℃ for 4 and 6 months
respectly. were sampled at fixed periods to measure the
changes of and chemical properties and different sensory
evaluations.The results showed that the heating conditions of
packaged guava puree and guava nectar base are 98℃, 60 sec
105℃, 48 sec respectly. There were no significant changes
quality of puree and nectar base under 5℃ storage, but tion
occured when stored at 20℃ and 35℃. It was evident
quality deteriorated more rapidly at high temperature.
physical and chemical constituents, such as pH, titratable
total soluble solid content and formalin nitrogen content did
change apparently under all storage conditions. But, vitamine
sucrose, tannin, Hunter L value, viscosity and total amounts
of volatile components decreased as storage temperature and
increased. However, frutose, glucose, furfural,
hydroxymethyl furfural, Hunter a, b and browning index
increased as temperature and time increased. The
deterioration rates different between these two aseptic
samples, but with the same reaction trend. Different
sensory evaluation also indicated color, aroma, flavor and
overall acceptance of guava puree and nectar base remained
constant during storage period under 5 whereas more
pronounced difference were beared with higher temperature and
extended storage time under 20℃ and 35℃ acceptance) could be
drawn Arrhenius plot according to its reac- tion rate at
different temperatures. This profile would provide an useful
basis for prediction of shelf life of guava drinks under
given storage conditions.
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