## 3 Discussion
### Effect of Various Heat Treatment Methods on the Sensory Profile of Basil Infusions  
Herbs play an important role as a flavoring agent in food technology. The assessment of the influence of the sous-vide method on the sensory profile of herbs was not easy and required the use of a neutral food matrix (water), which would absorb flavor compounds. The use of foods as carriers, due to their complexity (protein, fats, carbohydrates, water, etc.) and interaction between food ingredients, could make the interpretation of the results even more difficult. For these reasons, it was decided to evaluate the influence of temperature on the composition of volatile compounds and to relate the results to flavor profiles using an aqueous matrix. The phase (water or steam state) in which aroma compounds are located contributes to a better perception of odor. Heating a substance in the mouth changes its state from water to steam and improves the perception of smell [42]. The flavor sensations emerge as a complex process, the first stimulus substances are already released in the mouth, then by retronasal olfaction, aromas are transported from the oral cavity to the nasal cavity, where they connect with the olfactory receptors. During the consumption of products, many physicochemical changes take place in the oral cavity, and volatile compounds are also released. This process is influenced by the components of saliva, e.g., proteins, teeth, and tongue [43; 44]. This study did not demonstrate a significant effect of sous-vide cooking temperature on the odor and flavor profile evaluated by panelists. The reason for this is a long infusion time that leads to blurring the differences in intensities or not sufficiently differing parameters of the process. Although significant differences were detected using chromatographic methods, trained and experienced experts could not perceive them. No significant differences in hedonic assessment of kenaf leave tea with different temperatures and infusion times were reported by [PERSON] and [PERSON] [45]. On the other hand, a significant effect of temperature on the odor and flavor of herbs was shown in the research by [PERSON] et al. [46]. These authors showed that oils macerated with basil or oregano at 60 \({}^{\circ}\)C were characterized by a higher liked odor (in the case of oregano, also flavor) than those prepared at 20 \({}^{\circ}\)C. However, the opposite tendency was observed in the case of the desirable taste of rosemary oil. Moreover, it was found that herbal oils with a more intense aroma (rosemary) were rated higher in terms of overall appearance, color, taste, and smell. More pronounced changes in flavor and odor intensity are visible during the drying process. Basil leaves that were oven-dried at a mild temperature of 60 \({}^{\circ}\)C reached the highest score for aroma, due to the least degradation of the aroma-flavor compounds [47]; however, the authors carried out the process without the use of water, and the research conditions were different than in this study. Higher temperatures of other types of basil heat treatments, such as drying, affect the sensory quality of basil. It usually elicits a decrease in fresh, floral, and herbaceous odor intensity, while increasing spicy, hay-like, sweet, earthy, and woody intensity [48]. The applied temperature influences the efficiency of extraction by modulating the physico-chemical properties of water. Higher temperature tends to lower the polarity of the water, increasing the solubility of the less polar compounds in the water [49]. In our research, although not significant, the intensity of the astringent sensation was slightly more notable in basil infusions prepared at a higher temperature, while it was fresh odor and flavor as well as basil flavor in infusions seeped at a lower temperature. This is in accordance with the findings of [PERSON] and [PERSON] [50], who found that bitterness and astringency become stronger while green-related attributes become weaker as the brewing time and water temperature of green tea increases.