Concentration of dairy flavour compounds using pervaporation

Concentration of aroma compounds from an industrial solution of soluble coffee by pervaporation process

“…Although pervaporation has been successfully used in aroma recovery from fruits and juices, alcoholic drinks, dairy flavors and seafood, most researchers have utilized synthetic solutions to represent real systems ( Rafia et al, 2011;Peng and Liu, 2003;Isci et al, 2006;She and Hwang, 2006a,b;Pereira et al, 2006;García et al, 2008;Diban et al, 2008;Olsson and Tragardh, 1999;Borjesson et al, 1996;Rajagopalan and Cheryan, 1995;Karlsson et al, 1995;Overington et al, 2008Overington et al, , 2011 Bourseau et al, 2014). Only a few researchers have already worked with real matrices such as Zhang and Matsuura (1991), Alvarez et al (2000), Cassano et al (2006), Aroujalian and Raisi (2007), Raisi et al (2008), Catarino et al (2009), Olmo et al (2014.…”

Membrane-Based Extraction Techniques in Food Analysis

“…Molecules with high chemical affinity are attracted by the membrane layer and are diffused through it, while molecules with low affinity are retained. For example, hydrophilic membranes have high affinity to water molecules and so allow water to diffuse through the membrane while preventing other molecules from doing so (it is mainly used to remove water from aqueous streams), 71-73 while hydrophobic membranes will do the opposite (e.g., it is used to remove and determine sulfur dioxide in wine, vinegar, beverages, 74 and different solid foods 75 or concentrate dairy flavor compounds), 76 and organophilic membranes reject certain molecules while having an affinity for others and are used to separate complex mixtures. The separation is made at the molecular level by means of polarity differences and vacuum application, so that molecules of similar type are driven in a vapor phase into one reservoir while the other portion of the liquid mixture is retained in the original one to obtain an effective separation and a high purification of the species of interest.…”

Effect of feed pH and non-volatile dairy components on flavour concentration by pervaporation

“…Details of the pervaporation procedure have been published previously (Overington et al, 2008). Triplicate pervaporation runs were carried out with each of the feed mixtures listed above, using a 0.012 m 2 hydrophobic polydimethylsiloxane membrane (active layer thickness 0.5 lm; supplied by Helmholtz-Zentrum Geesthacht -Centre for Materials and Coastal Research, Geesthacht, Germany).…”

“…Flavour compound concentrations in all permeate samples, as well as retentate samples not containing dairy ingredients, were determined using gas chromatography (GC), with the same conditions as described previously (Overington et al, 2008).…”