Comparison of Volatile Organic Compounds, Quality, and Nutritional Parameters from Local Italian and International Apple Cultivars

Abstract

Apple cultivars ‘Annurca’ and ‘Limoncella’ are grown locally in the Campania region of Italy and are valued for their distinctive flavour and characteristics, including a high content of nutritionally important bioactive compounds. However, apples are typically stored chilled for several months before consumption, so it is important to assess if the valuable characteristics are still present after postharvest storage. Here, we compare the quality, nutritional parameters, and aroma of these two cultivars with two widely grown international cultivars, ‘Golden Delicious’ and ‘Fuji’, after 60 days of storage. The aroma profiles of all four apples were analysed using thermal desorption and gas chromatography–time-of-flight mass spectrometry. We show that the local cultivars are distinct from the international cultivars in their bioactive compound content and their antioxidant activity. ‘Limoncella’ shows high sugar content, which may be acting as a cryoprotectant during storage, and high total phenolics in the flesh, which is of nutritional interest. We identified 104 volatile organic compounds (VOCs) and showed that the overall aroma profile is distinct for each cultivar, containing 11 published odorant compounds. The ‘Annurca’ profile is uniquely low in esters. Seven VOCs retain good discrimination across the four cultivars and, together with the quality and nutritional data, separate the two local cultivars from the international cultivars by hierarchical clustering. Overall, the data emphasize the unique characteristics of the two local cultivars and their value.