Impact of biopolymers added to a grapefruit puree and freeze-drying shelf temperature on process time reduction and product quality

[Display omitted] •Freeze-drying process has been studied as to obtain a grapefruit snack-type product.•Gum Arabic and bamboo fiber allow to obtain a firmer and crunchy product.•Heating to 40 °C may be recommended in order to shorten the process time. Freeze-drying provides high quality foods, despite the long time involved in the operation. Shortening the process time by increasing the heat supplied for sublimation to occur could affect the product quality. In this study, the impact of adding gum Arabic and bamboo fiber to a grapefruit puree and of raising the shelf temperature to 40 °C during freeze-drying has been considered. The increase in temperature allows a 57.5% time reduction and promotes a porosity increase without any impact on the cake’s color and vitamin C content. The addition of biopolymers does not affect the drying kinetics and allows a crunchier and firmer cake to be obtained, despite the color changes and the fact that vitamin C becomes less available. In conclusion, raising the shelf temperature to 40 °C significantly reduces the freeze drying time without noticeably impairing the product, and the addition of biopolymers improves the product characteristics without adversely impacting upon drying times.