Evolution of typical aromas and phenolic compounds of a red-fleshed apple throughout different fruit developmental periods in Xinjiang, China.

ABSTRACT

Red-fleshed apple is attracting more and more attentions from both consumers and researchers thanks to its pleasant appearance and flavor. Accumulation and development of aromas of apple fruit are important factors to understand the fruit quality of a new cultivated variety. However, knowledge on the key aroma components development and accumulation of red-fleshed apple (Malus sieversii f. neidzwetzkyana(Dieck) Langenf) in Xinjiang through the fruit developmental periods is insufficient. In this paper, free and bound form aromas of a red-fleshed apple since young fruit period through expansion period and conversion period to ripen period were comparatively studied. We classified aroma substances according to the compound category (esters, aldehydes, alcohols, terpenes, and aromatics), and to the odor types. The concentration of bound form aroma compounds were higher than that of free form throughout the 4 periods and showed different evolution trends. Among the 4 periods, the bound aroma was the most in the expansion period; and terpenoids showed the greatest potential to release free form aromas. Total aromas were found the lowest concentration in expansion period and the highest concentration in ripen period. The observations in this study will provide theoretical support for the research of typical aroma formation regularity of red-fleshed apple, and guide for the aroma enhancement regulation.