Impact of crossflow microfiltration on aroma and sensory profiles of a potential functional citrus‐based food

Abstract

BACKGROUND Citrus juices can be cold‐concentrated by crossflow microfiltration (CMF) in order to obtain functional foods enriched in carotenoids, flavonoids and pectins. The work aimed to characterize the organoleptic quality of this type of micronutrient‐dense foods through their aroma profile and sensory analysis. Two citrus concentrates with and without a diafiltration step were compared. RESULTS Both citrus products were very different, linked to aroma compound, sugar and organic acid contents. Due to its sugar/acidity balance and its better aromatic profile responsible for the citrus–floral flavour, the concentrate without diafiltration was preferred by the sensory panel. Thanks to a simple transfer model, we showed that retention of volatiles clearly varied from one aroma compound to another. The terpene hydrocarbons were the most retained by the membrane during CMF, probably because they were strongly associated with insoluble solids by adsorption. CONCLUSION Even though the process modified their organoleptic profiles, both citrus‐based products were well rated and can be consumed directly as pleasant functional drinks. © 2022 Society of Chemical Industry.

Core-Shell Structured Carbon@Al2O3 Membrane with Enhanced Acid Resistance for Acid Solution Treatment

“…Acidic solutions are common in production and processing chains, such as pharmaceutical production, food processing, textile dyeing, and metal smelting. Membrane technology has been applied to a large number of inorganic and organic acids [28][29][30][31]. Compared to neutral systems, acidic solutions require a higher stability for the separation membranes.…”

“…This might result in the deterioration of the membrane strength and dealumination and introduces impurities into the permeate [35,36]. On the other hand, the acidic components may be adsorbed by coordination with the abundant hydroxyl groups on alumina [21] during the production and processing of natural herbal extracts and juices rich in acidic active ingredients, which may result in irreversible loss of acidic active ingredients and destruction of the flavors [28,29]. To improve the stabilities of alumina membranes and reduce adsorption, various methods have been used to modify alumina ceramic membranes, such as surface coating with raw micro/nanoparticles and doping with suitable additives, to modulate the active sites [37][38][39].…”