## 2 Results and Discussion
### Volatilome of Different Palm Date Products
This enhancement is attributed to mechanical disruption (shredding) and thermal treatment, which facilitate cellular rupture and the subsequent release of volatiles previously bound to or entrapped within the fibrous matrix. The volatilome of the further processing steps is instead the result of the fermentation effect on date juice. Nevertheless, the modification of the volatilome can be observed during processing, showing the linear evolution of the volatile components and their ratios as an expression of the metabolic effect of the co-operative microorganisms Figure 2.  
In the date palm fruit, the development of aromatic compounds is linked to the botanical origin and ripening stage. At the Tamer stage (final maturation), alcohols and esters are predominant, with high levels of alcohol being particularly notable [16]. In fact, during fruit ripening, alcohols derived from amino acid metabolism were found to be the most important chemical class. Fusel alcohols (i.e., aliphatic alcohols with more than two carbon atoms) are produced via the Ehrlich pathway, where \(\alpha\)-ketoacids produced by the initial transamination reaction are subsequently decarboxylated into aldehydes, which are then reduced into alcohols [6]. Compared to the other matrices, the abundance of 1-pentanol, 1-hexanol, and 2-ethyl-1-hexanol confirms this data in Figure 3 [14]. The palm fruit has a high content of lactones, correlated with the presence of butylacetone, an element which then dissolves with fermentation, and of the terpene class in which limonene stands out. In the analyzed fruits, the presence of terpenes provides us with some more information on the derivation of the product since many other derivatives do not have it [16]. Another important group of compounds are the esters, such as methyl acetate and 1-methoxy-2-propyl acetate. However, their presence is lower than one might expect from the literature. In fact, date palms show a large development of ethyl acetate, ethyl occanoate, or ethyl decanoate. These compounds were not detected in the chromatographic profiles of the analyzed samples, which may be attributed to the specific characteristics of the fruit matrix and the nature of the comparison. In the literature, comparisons are typically made among different date palm cultivars, whereas in this case, the contrast involves distinct matrix types. Overall, the concentration of these compounds appears to be relatively low in fruit matrices compared to other substrates. Among the evaluated matrices, juice demonstrated a greater capacity to retain volatile compounds, likely due to the limited progression of fermentation. Compared to the native fruit, the juice exhibited increased concentrations of several volatiles, including acetaldehyde, ethyl acetate, 2,3-butanediol, selected fusel alcohols, and furanic aldehydes. Notably, 2,3-butanediol--one of the dominant volatiles in the juice--is a known bacterial metabolite typically formed during the early stages of fermentation. In addition, esters such as ethyl acetate and isoamyl acetate were detected, along with elevated levels of furan-derived compounds, particularly 5-hydroxymethylfurfurfural (HMF) and 2-furanmethanol. These latter  
Figure 2: The volatilome’s richness of the different palm date product derivatives. compounds are likely products of thermal degradation of ascorbic acid (vitamin C) [17]. However, in this case, they are most probably formed during the thermal treatment before filtration. Given the time during which the fruits are boiled during thermal processing, furfural could be generated via the caramelization of fructose rather than Maillard reaction of fructose/glucose with aminoacids as reported from [18]. Trans-linalo oxide is present only in juice (Figures 3 and 4) as the potential result of the biotransformation of linalool to pyranoid from fungi or derived from enzyme-catalyzed reactions [19]. In these cases, the enzyme lipase catalyzes epoxidation of double bonds analogous to the chemical reaction with a peroxycarboxylic acid [20].