Carrier type, fat content, capsaicin concentration and sample temperature: effects on perceived pungency

In a study of pungency in food systems, three carriers (water, cheese sauce, starch paste) with varying fat levels (none, low, medium, and high), synthetic capsaicin concentration (0.0, 0.4, 0.8, and 1.3), and serving temperatures (25 and 38°C) were formulated. The study was an incomplete block design. Proximate composition and viscosity were measured for each batch of sample. Panelists were selected and trained according to ASTM (1991) method E 1083-88. They evaluated sensory heat intensity every 15 sec for 3 min, two samples per sittings, two sittings per day (block) for 12 days. Sixty-four samples were included (3 carriers x 1,3, or 4 fat levels within carrier x 2 serving temperatures x 4 capsaicin levels).

The data were analyzed to determine differences attributable to main effects (capsaicin level, carrier, fat within carrier, temperature, block, and time) and interactions. Time-intensity parameters (maximum intensity-MAX, time to maximum intensity-TMAX, and rate of release-RATE) were evaluated.

Viscosity differences were observed among fat levels and serving temperatures within each carrier. However viscosity was not correlated (p>0.05) to MAX values. Water MAX scores were generally higher than those for other carriers within the same capsaicin level. MAX scores tended to decrease as fat level increased. TMAX did not appear to be a useful parameter in this study. RATE values for room temperature samples were significantly lower than those for warm samples.

Heat intensity scores increased as capsaicin concentration increased across the 3-min time interval. Intensity of starch samples across time decreased as fat level increased. A similar trend was not observed with cheese sauce samples.

Overall, intensity scores increased as capsaicin concentration increased. The increase was related to carrier and fat level. Water samples (0.4, 0.8, and 1.3) were perceived as more intense than cheese or starch samples at the same capsaicin level. Generally, increasing the fat level resulted in lower intensity scores. Temperature, in most cases, did not affect the pungency. The training method was effective when water was the carrier. However physical or chemical interaction that occur in simple food systems may influence perceived pungency.