The comparison of flavor, nutrient composition, and antioxidative activity between Kyo-kurenai and Hamabeni snow carrots (Yukishita carrots)

Abstract

"Yukishita" carrot, or snow carrot, is a branded vegetable produced in heavy snow areas where the vegetable is embedded in snow during winter. This snow carrot is known to have a good flavor via its adaptive response of cold acclimation to obtain freezing resistance. In the present study, we investigated the nutrient composition, carotenoid content, antioxidative activity, and flavor of a novel snow carrot of Kyo-kurenai in comparison with those of traditional Hamabeni snow carrot. Regarding the constituents, Kyo-kurenai snow carrot had very similar nutrient composition and taste components to those of Hamabeni snow carrot. In contrast, the level of lycopene in the Kyo-kurenai snow carrot was 20 times higher than that of the Hamabeni snow carrot, while its total carotenoid content was comparable to that of the Hamabeni snow carrot. Further, antioxidative activities evaluated by electronic spin resonance (ESR) method for water-soluble components and by singlet oxygen absorption capacity (SOAC) method for carotenoids were higher in the Kyo-kurenai snow carrot than those in the Hamabeni snow carrot. The analyses of volatile compounds by gas chromatography-mass spectrometry (GC-MS) and taste components by taste sensor suggested that these snow carrots have similar odor and taste components, although the sensory evaluation of the Kyo-kurenai snow carrot resulted in lower score of overall quality as compared to that of the Hamabeni snow carrot. Taken together, these results indicate that the Kyo-kurenai snow carrot has both properties of high antioxidative activity due to its high lycopene content and good flavor comparable to that of the traditional Hamabeni snow carrot.