Mechanisms of flavor release and perception in sugar-free chewing gum

by Potineni, Rajesh Venkata.

The flavor properties of chewing gum are undoubtedly a key product attribute for consumption. However little is known about how many of the various ingredients (i.e. flavor solvents) in chewing gum alter flavor delivery. Consequently, defining mechanisms which influence flavor release in chewing gum is important for understanding its product quality and possibly may also translate to drug delivery applications for the pharmaceutical industry. The first objective of this study investigated the influence of three flavor solvents on the aroma/taste/textural properties in a sugar-free chewing gum. Model chewing gums made with [0.67%; triacetin (TA) or propylene glycol (PG) or medium chain triglycerides (MCT)] and without flavor carrier solvent. The chewing gums were analytically characterized in vivo for three panelists over a period of 12 min. Volatile analysis of cinnamaldehyde, L-carvone, piperitone, jasmone was conducted using Atmospheric Pressure Chemical Ionization-mass spectroscopy (APCI-MS). Sorbitol release from saliva was tracked using High pressure Liquid Chromatography (HPLC) coupled with Refractive Index Detector (RID), while the textual properties (softness) were measured using TA-XT2. Furthermore, the perceived flavor properties of these chewing gum samples were measured using a time-intensity sensory study (TI) on the aroma (cinnamon-like), taste (sweetness) and textural (effort to chew) attributes using a trained sensory panel. Flavor solvent addition to chewing gum did not significantly influence the aroma release profiles of all the 4 compounds. However, the sorbitol release rate was significantly lower for chewing gum made with TA compared to the other treatments. iv The sensory analysis was in agreement with the analytically data; lower levels of sweetness and cinnamon-like flavor intensity were perceived for chewing gum made with TA were observed, suggesting taste-aroma interactions. Chewing gums formulated with TA or MCT were reported to be softer (based on texture analysis) then with PG or no flavor solvent addition. However, no correlations were reported between the instrumental texture analyses of the chewing gum (softness) and the flavor release. Overall, flavor solvent choice did influence the sorbitol release in chewing gum matrix due to unique plasticizing/softening mechanism of the solvent utilized. The second objective of this study was to investigate the mechanisms for cinnamaldehyde release in a sugar-free chewing gum. Chewing gums containing (25%-Paloja gum base, 61 %-sugar alcohol, 4%-glycerine, 0.46% sweeteners, and 0.02% lecithin) were made with varying concentrations of cinnamaldehyde. Additionally chewing gums were made with p-cresol (similar log P as cinnamaldehyde). A cinnamaldehyde or cresol flavored gum base (no sugar alcohol) was also made to investigate the role of the gum base on flavor release. Three panelists were asked to chew gums or flavored gum base, while aroma release profile was tracked from the nose exhaled breath using APCI-MS over a period of 8 min. The release profile of cinnamaldehyde from chewing gum was found to correlate with the sugar alcohol release in a sugar free gum. Chewing gums made with varying amounts of cinnamaldehyde (0.29 - 2.9 mg/g of chewing gum) did not show any differences in release pattern suggesting no concentration effect. Furthermore, the cinnamaldehyde release pattern from the gum base was similar to cresol or as v predicted from the log cP value (distribution coefficient between the gum base and water). These findings suggested cinnamaldehyde was interacting with the sugar alcohol phase, possibility due to transient hemi-acetal reactions mechanisms, which resulted in a more rapid release rate than would be predicted based on the hydrophobicity of this compound.