## 1 Introduction  
The fruits of the date palm (_Phoenix dactylifera_ L.) are a traditional and widespread food source in Southwest Asia and North Africa. They have exceptional nutritional, health, and economic value, which can be used not only for direct consumption in the form of dried or fresh fruit, but also for by-products such as energy bars, syrups, pastes, jams, desserts, sauces, and pickled dates [1, 2]. Other products of fermented dates are alcoholic beverages such as wine, beer and liquor, and non-alcoholic beverages such as vinegar and juices [3]. Historically, dates have served both as a source of natural sweetness and nutritional value and as a functional substrate in the production of vinegar [3]. Scientific research and global market interests are increasingly driving towards healthy food and lifestyle (always referring to the Western world). According to various market analyses, global fermented foods and beverages are posed to acquire an important position in the food industry. During the forecast period between 2019 and 2026, this market is expected to grow at a compound annual growth rate (CAGR) of 8.1% [4, 5, 6, 7]. As a result, different foods and beverages have been introduced to the market that have many expansion opportunitiesas products with improved properties. In the fruit sector, as well as others, the waste from the fruit business can be used in the production of brews and vinegars [8]. Date palm fruits are a flexible raw material, rich in nutritional elements and bioactive molecules such as carbohydrates, dietary fiber, polyphenols, carotenoids, and minerals. The high content of carbohydrates such as sucrose, fructose, and invert sugars (monosaccharides or disaccharides), which can make up to 75% of the dry weight of the fruit, lends itself to fermentation processes and can therefore be used to produce a variety of fermented beverages. Fermentation and enzymatic processing techniques form the basis of several bioprocessing strategies for the valorisation of date palm fruits and waste. The latter could be used as a raw material in the food industry to create high-sugar syrups that are used to produce both alcoholic and non-alcoholic fermented beverages, through the use of mainly lactic acid bacteria (LAB), yeasts, and acetic acid bacteria (AAB) [9; 10; 11; 12; 13; 14]. A substantial proportion of low-ripening dates is discarded each year due to factors such as physical damage, unappealing morphology, or insufficient ripeness and size. There is a financial loss when low-grade secondary dates are not used. Consequently, efforts were made to develop intermediate date-based food products as functional co-products for industrial use, embracing the circular strategy and sustainable economy [12; 13].  
The sensory qualities of a product such as aroma, taste, and color are linked to its chemical composition. Volatile compounds influence flavor perception and complexity, while phenolic compounds affect taste (bitterness, astringency), color, body, mouth-feel, and aging [14; 15]. The chemical composition defines the drink's identity and is influenced by the fruit, ripeness stage and fermentation process. The purpose of the research was to characterize the HS-SPME-GC-MS compositional profile with regards to different palm date derivatives (juice, alcoholic derivative, and vinegar), enabling us to understand the chemistry behind the evolution of volatiles through the fermentative process. In parallel with the chromatographic profiling, the quantification of several quality markers was also carried out such as total and volatile acidity, ethanol, acetoin, and total polyphenic content.