DENTIFRICE ABRASIVES AND FLAVOR RELEASE 307 18 17 15 14 ß HYD. ALUMIFIR • * DICALSILICA ' HYD. 1 ABRASIVE LEVEL Figure 2. Abrasive affinity for flavor in gel humectant system. headspace sampler and a flame ionization detector was used throughout this work. The flavor was mint-based, containing components such as menthol, menthone, and car- vone. Experimental mixtures of abrasive, flavor, and other dentifrice components were formulated to be in the same ratio as these components in a commercially available dentifrice. One hundred and forty milligrams (approximately 0.10 ml) of dentifrice (0.9% flavor concentration)was dispensed into a 22-ml headspace vial and weighed to the nearest 0.0001 g, to provide approximately 1.25 mg of flavor in the vial. Since many of the mixtures varied considerably in flavor concentration, the amount of sample added to headspace vials was calculated to keep a constant quantity of flavor. For ex- ample, with a mixture of 1.8% flavor concentration, a sample weight of 70 mg would be added to the vial. The vial was hermetically sealed by crimping an aluminum cap containing an aluminum-coated silicone rubber septum onto the vial. The sealed vial was placed into the sample carriage of the HS-100 headspace sampler which was pro- grammed to equilibrate each vial for five to seven hours at 40øC, achieving equilibrium. An aliquot of the headspace was then automatically injected onto a Supelcowax 10 bonded-phase fused-silica capillary column, 30 x 0.32 mm with a 0.25 •m film

Table I Effect of Dical and Hydrated Silica on Flavor Released in Simple Systems A. Dical/H20 Sample # Sample components Total area (GC units) % Change* A Flavor 13.64 - 0.68** -- B Dical/flavor 13.15 -+ 0.92 - 3.6 D Dical/SLS/flavor 13.69 -+ 1.13 + 0.4 I Dical/H20/flavor 16.04 - 0.89 q-17.6 F H20/SLS/flavor 10.25 --- 1.17 -24.9 O Dical/H20/SLS/flavor 10.15 --- 1.22 - 25.6 NS NS 0.001 0.001 0.001 B. Hydrated silica/H20 Sample # Sample components Total area (GC units) % Change A Flavor 13.64 - 0.68 -- C Hyd. silica/flavor 7.78 --- 0.85 -43.0 E Hyd. silica/SLS/flavor 9.63 - 1.05 -29.4 J Hyd. silica/H20/flavor 14.97 - 0.96 q-9.8 F H20/SLS/flavor 10.25 + 1.17 -24.9 P Hyd. silica/H20/SLS/flavor 10.42 - 0.61 -23.6 o.ool o.ool 0.042 o.ool o.ool C. Dical/glycerine Sample # Sample components Total area (GC units) % Change A Flavor 13.64 --- 0.68 -- B Dical/flavor 13.15 - 0.92 - 3.6 D Dical/SLS/fiavor 13.69 -+ 1.13 +0.4 K Dical/gly/fiavor 14.14 _ 1.17 + 3.7 G Gly/SLS/flavor 12.49 + 0.99 -8.4 Q Dical/gly/SLS/flavor 9.84 --- 1.06 -27.9 NS NS NS NS 0.001 D. Hydrated silica/glycerine Sample # Sample components Total area (GC units) % Change A Flavor 13.64 - 0.68 -- C Hyd. silica/flavor 7.78 _4- 0.85 -43.0 E Hyd. silica/SLS/flavor 9.63 - 1.05 -29.4 L Hyd. silica/gly/flavor 14.97 - 0.86 q-9.8 G Gly/SLS/flavor 12.49 - 0.99 -8.4 R Hyd. silica/gly/SLS/flavor 12.58 - 0.60 -7.8 0.001 0.001 0.032 NS 0.037 E. Dical/70% sorbitol Sample # Sample components Total area (GC units) % Change A Flavor 13.64 --- 0.68 -- B Dical/flavor 13.15 -+ 0.92 - 3.6 D Dical/SLS/flavor 13.69 --- 1.13 +0.4 M Dical/70% sorb/fiavor 13.57 --- 1.41 - 0.5 H 70% Sorb/SLS/flavor 12.20 ___ 1.26 - 10.6 S Dical/70% sorb/SLS/fiavor 12.61 __+ 1.09 -7.6 NS NS NS 0.065 NS F. Hydrated silica/70% sorbitol Sample # Sample components Total area (GC units) % Change A Flavor 13.64 - 0.68 -- C Hyd. silica/flavor 7.78 --- 0.85 -43.0 E Hyd. silica/SLS/flavor 9.63 - 1.05 -29.4 N Hyd. silica/70% sorb/flavor 12.70 -+ 1.14 -6.9 H 70% Sorb/SLS/flavor 12.20 - 1.26 - 10.6 T Hyd. silica/70% sorb/SLS/flavor 12.47 _ 0.83 -8.6 o.ool o.ool NS O.O65 0.047 * Relative to the flavor control (sample A). ** Standard deviation of the mean n = 7.