Concentration of pomegranate juice by forward osmosis or thermal evaporation and its shelf-life kinetic studies.

Pomegranate (Punica grantum L.) fruit juice was concentrated by forward osmosis or thermal evaporation and the
samples were stored at ambient (25 ◦C) and accelerated (37 ◦C) storage conditions. The anthocyanin content of
raw, reconstituted forward osmosis as well as reconstituted thermally evaporated pomegranate juice were 421.1,
414.4 and 357.2 mg/kg respectively. The physicochemical attributes of pomegranate juice concentrate such as
anthocyanin content, antioxidant activity, browning index, and hydroxymethyl furfural showed that the quality
of the concentrate was markedly affected by storage conditions. Based on the hydroxymethyl furfural content
(≤25 mg/kg), it was concluded that the forward osmosis concentrated juices could be stored at ambient and
accelerated conditions for ~101 and ~66 days, respectively. While, thermally concentrated juice could only be
stored for less ~31 and ~3 days, respectively. Forward osmosis could be a method to concentrate pomegranate
juice with minimum effect on quality attributes with extended shelf life.