# Exploring the Typicality, Sensory Space, and Chemical Composition of Swedish Solaris Wines
## 4 Discussion  
One of the main results of this work is the lack of a consensus regarding Solaris typicality among the Swedish wine experts. This result was contrary to previous works on varietal typicality which have shown fair consensus between French experts for Sciaccarelo wines [25] and Chardonnay and Melon de Bourgogne varietal wines [21]. A possible explanation is that French wine industry is centuries old, with well-established training oenology programs and thousands of examples of these varietal wines available for tasting. Therefore, these experts have developed a common representation of the sensory style associates to each category through extensive tasting. In contrast, the Swedish wine industry is relatively young and the number of available Solaris wines on the market is much lower. These two factors could make it more difficult for Swedish wine professionals to develop a shared sensory representation of Solaris. Moreover, the aroma profiles showed at least two different wine styles which makes prototype abstraction even more difficult for tasters. At this stage, Swedish winemakers do not have an association of a wine style to what a typical Swedish Solaris should smell and taste like. Nevertheless, the volatile composition showed that compounds such as 4-MMP, ethyl propionate, ethyl 2-Methyl propanoate, and diethyl succinate could discriminate between Sol and non-Sol wines. A recent study has shown relevant information regarding the presence of thiol precursors in _Vitis_ hybrid varieties. Despite Solaris not being included in the study, the cited work has shown that some _Vitis_ hybrid grape cultivars such as SV023 and Zarya Severa, have a larger concentration of 4-MMP precursors than Sauvignon Blanc [52]. These compounds could influence the \"fruity\" and \"green\" Solaris style. The analysis of methoxypyrazines should be considered in future studies, as they are known to play a major role on the \"greenness\" perception the wines. A study from [PERSON] (2013) showed not only that 2-Methoxy-3-isobutylmethoxypyrazine (iBMP) is associated with green notes, but also that at high concentration iBMP could have a suppressive effect over the tropical aromas associated with thiols. The author also showed that at high levels, thiols could also suppress the \"green notes\" from iBMP [53]. Understanding the proportions between Solaris thiols and methoxypyrazines could help to understand the potential different wine styles. Another important metabolite, at least from a health standpoint, is methanol. Previous literature pointed out that wines from fungus resistant grapes tended to show higher methanol concentrations than wines from _Vitis_ _Vinifera_ grapes [12]. In our case, no significant differences were found for methanol between Sol and non-Sol wines (t = 2.06, \(p\) = 0.06). Furthermore, all the samples had methanol concentrations below the OIV (Organisation Internationale de la vigne et du vin) limit for white wines (250 mg/L). The differences in taste and mouthfeel were more obvious between Sol and non-Sol wines for both sensory evaluation and chemical composition. The bitterness and saltines associated with Sol wines could be explained by the levels of succinic acid as this organic acid has been shown to have a salty and a bitter taste [50]. Additionally, it can also play a role on the aroma as it has been shown to be involved in the formation of aroma-active esters, such as diethyl succinate [51], which was one of the discriminant aroma compounds between Sol and non-Sol. The presence of certain cations, such as Ca, K, Mg, and Na had previously been associated with wine saltiness in Mexican wines [54]. However, the salt content did not imply a higher saltiness perception in South African Chenin Blanc and Pinotage wines [55]. In the present study, Mg was the only cation found to be significantly higher in Sol wines(perceived as saltier) than non-Sol wines. However, the impact of Mg on perceived saltiness is yet to be demonstrated in a wine matrix.