|Margaria, Carlos - USDA|
Submitted to: Proceedings of Florida State Horticultural Society
Publication Type: Proceedings
Publication Acceptance Date: December 5, 2002
Publication Date: December 31, 2002
Citation: MARGARIA, C.A., GOODNER, K.L., BALDWIN, E.A. DETECTION AND IDENTIFICATION THRESHOLD VALUES FOR KEY FLAVOR COMPONENTS IN AN ORANGE JUICE MATRIX. PROCEEDINGS OF FLORIDA STATE HORTICULTURAL SOCIETY. 2002. v. 115. p. 53-54. Interpretive Summary: Key components responsible of fresh orange juice flavor were analyzed using a sensory panel to determine the minimum concentration at which they are detected in orange juice (detection thresholds). The concentrations at which those components were recognized were also analyzed (identification threshold). This information would provide the fruit juices and beverage industries with reliable data to assess the quality of their products.
Technical Abstract: Due to the complex nature of orange juice, threshold values for key flavor components could differ significantly from those values reported in simpler systems, like water. In order to provide the citrus industry with reference values closer to the real situation in orange juice, different orange juice flavor compounds were tested. The matrix used was a deodorized reconstituted orange juice concentrate obtained from local industry. The day previous to the assay the concentrate was diluted in de-ionized water to 11.7 Brix, spiked with the corresponding compound and stored at 4°C. A 10-member panel (4 female, 6 male) followed the E 679 method (ASTM, 1997) to determine detection and identification thresholds. The tests were carried out at room temperature using 5 concentration levels, each separated by a factor of 3, placed in capped plastic cups that were maintained at 4°C until analysis. Although results are not yet conclusive, there appears to be a difference between orthonasal (O) and retronasal (R) detection thresholds as reported by the panelists during the sessions, and there was also a trend towards lower threshold values for women. Detection thresholds for vanillin in juice were between 150 and 5300 times lower than the reported values in water (O= 0.13 g/L; R=0.16 g/L compared to 20-680 g/L and 30 g/L in water, as reported by Rychlik et al. (1998). Identification threshold for vanillin in juice was about one order of magnitude higher than detection threshold (O=1.44 g/L and R=0.93 g/L). Preliminary results also suggest a positive synergistic effect between vanillin and sweet taste perception.