[3Da] Sensibility evaluation, Organoleptic evaluation

[3Da-07] Sweetness of watermelon in eating evaluation

*MASAKO OSAWA¹, SHINGO FUJITA¹, TAKAHIRO INAKUMA² (1. Hagihara Farm. co., Ltd., 2. Kagawa Nutrition University)

Keywords:watermelon, eating evaluation, sweetness, Brix, sugar content and composition

[Objective] In watermelon, sweetness is the most important factor. Generally, Brix is used as an objective index of sweetness. However, it is assumed that Brix ≠ sweetness, as the actual sweetness perceived depends on the sugar content and composition, even at the same Brix. In this study, the sweetness and palatability of watermelons were evaluated, and the relationship between the sweetness and Brix and sugar-related factors were investigated. [Methods] Twenty-two watermelon cultivars were evaluated by 12-21 men and women for sweetness and palatability. Brix was measured, and sugar contents (fructose, glucose and sucrose) were analyzed by HPLC. Differences and correlations among cultivars were investigated for sweetness, palatability, Brix, each sugar content, total sugar content, and predicted sweetness which were calculated from each sugar content. Amino acids were analyzed using an automated amino acid analyzer with LC-MS for the cultivar of 'Matsuribayashi 777 (777)'. [Results] Significant differences in Brix were found only between the three cultivars. However, significant differences in sweetness, palatability, each sugar content, total sugar content, and predicted sweetness were found among a wide range of cultivars. Correlations between sweetness and Brix, each sugar content, total sugar content, and predicted sweetness were weak. These results showed that Brix does not necessarily equal sweetness, and other components are involved in sweetness. '777' had a higher content of sweet-tasting amino acids, and it was inferred that these amino acids may be involved in sweetness.