Effects of osmo-dehydration, blanching and semi-ripening on the viscoelastic, water activity and colorimetry properties of flour from three cultivars of plantain (Musa AAB)

Abstract

The viscoelastic properties, water activity and colorimetry measurements of plantain flour produced by hot-air dehydration of three cultivars, French Horn, False Horn and True Horn local plantains were studied. Treatments given to the plantains before the hot-air dehydration were osmo-dehydration, hot-water blanching and semi-ripening and fresh unripe. The best pasting characteristics occurred for True Horn local and False Horn osmo-dehydrated flours. Water activity and moisture content were 0.27–0.39 aw and 5.08–7.25%, respectively with the lowest recorded for False Horn osmo-dehydrated flour. Colour parameters were in the range of 87.34–79.56 and 15.71–26.74 for L⁎ and b⁎, respectively. The least browning colour (a⁎) was exhibited by True Horn local and False Horn osmo-dehydrated flours. Statistical significances (P < 0.05) were recorded for water activity, moisture content and a⁎ colour parameter between process treatments for fresh unripe, semi-ripe, osmo-dehydration and blanching whereas no statistically significances occurred for varietal differences for False Horn, True Horn local and French Horn plantains. However, the viscoelastic properties were significant for F-ratios at P > 0.05. Process treatments of osmo-dehydration, blanching and semi-ripening contribute significantly to the differences for water activity, moisture content, browning effect and viscoelastic properties compared to plantain varieties, with osmo-dehydration emerging as the best treatment method. This work is a representation of peculiar differences for water activity, moisture content, non-enzymatic browning effect and viscoelastic properties among process treatments of osmo-dehydration, blanching, semi-ripening and fresh unripe. Important results were obtained for the flour industries for decisions on selecting osmo-dehydration among the process treatments for plantain (Musa AAB) flour in order to take advantage of the consumer demand for plantain flour.