## 1 Introduction  
Apple aroma is a crucial criterion to assess fruit quality. This organoleptic quality is due to several volatile organic compounds (VOCs) such as esters, alcohols, aldehydes, ketones, acids, and esters [1]. More specifically, 2-methyl butyl acetate, butyl acetate, and (E)-2-hexenal are reported as the most significant VOCs contributing to the typical apple aroma [2]. Most VOCs in apple juice are not genuine constituents of apples, but produced from precursors by enzymatic reactions upon squeezing [3, 4]. Apple variety, environment, ripening stage, storage, and processing procedure are some factors that influence the content of VOCs in apple juices [3]. Consequently, cider, a globally popular beverage, is obtained from the partial or total alcoholic fermentation of apple juice (raw material) [5]. The level of VOCs in ciders depends on the applied technology, the microorganisms involved in the fermentation process, ageing on lees, maturation, and storage conditions [4, 6, 7]. Typically, ripe or overripe (senescent) apples are used in cider processing due to their softened structures, thus resulting in higher juice yields and an increase in sugar content during apple ripening [8]. In fact, in a recent study, for all studied varieties, senescent fruits provided more aromatic fermented apple beverages [9]. The VOCs formed during the fermentation process, such as 3-methyl-1-butanol, 2-phenylethylhanol, ethyl butanoate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, ethyl 2-methylbutanoate, 3-methylbutyl ethanoate,hexanoic acid, octanoic acid, and 2-methyl butanoic acid, are responsible for the fruity odours of ciders [10; 11; 12].  
Currently, the food-quality programme of the European Union encourages food-origin protection through Protected Designation of Origin (PDO) and Protected Geographical Indication (PGI)) with the purpose of ensuring the quality of the final product [7]. Therefore, an analytical approach combined with a microextraction procedure should be developed to guarantee the genuineness of foodstuffs. An analytical tool widely used in the establishment of the volatile profile of apples, juices, and ciders is gas chromatography-mass spectrometry (GC-MS) combined with headspace solid-phase microextraction (HS-SPME) in order to define the authenticity and typicity of the samples using VOCs [4; 11; 13; 14]. This method is a valuable tool in the establishment of a volatile profile since it requires small amounts of a sample and no solvents, and it is fast, economical, reproducible, and sensitive.  
Concerning the evaluation of the authenticity and typicity of apple-related products using VOCs, [PERSON] et al. [13] used HS-SPME/GC-MS combined with chemometric tools (e.g., principal-component analysis (PCA)) to characterize the volatile fingerprint of apple juices from the island of Madeira. The obtained results revealed that VOCs could be used as authenticity markers to validate the variety and geographical origin of apple juices, providing local producers with numerous benefits. [PERSON] et al. [11] also established the volatile signature of apple ciders from five different geographical regions of Madeira by HS-SPME/GC-MS combined with chemometric tools. In the same context, [PERSON] et al. [14] evaluated the technology used in cider making, and differences in VOC composition were observed between ciders produced under intensified and traditional technologies. Despite the high potentiality of this methodology, few studies were performed to explore the similarities and differences of volatile profiles among apple fruits, juices, and cider samples. In this sense, the aim of this study was to establish the volatile profile of these apple matrices (fruits, juices, and ciders), from different apple varieties (Festa, Branco, and Domingos) from Madeira using HS-SPME/GC-MS. Then, the obtained data were subjected to the chemometric approach in order to find putative markers of apple variety.