## 1 Introduction  
Noble rot wine is a sweet wine made from grapes that have been botrytized with the beneficial fungus _B. cinerea_, also called noble rot. The process of botrytization is highly complex, involving both enzymatic transformations and the dehydration and concentration of the grape berries [1]. This transformation significantly elevates the concentrations of sugar, acidity, glycerol, minerals, and specific aroma compounds within the grapes.  
During botrytization, the grapes' inherent aromatic compounds are not only concentrated but also rendered more readily extractable from the skins during viniification. Consequently, botrytized wines exhibit a greater abundance of volatile aroma compounds compared to non-botrytized dry white wines [2]. Key compounds include furan derivatives(such as 5-hydroxymethylfurfural and sotolon), phenylacetaldehyde, and acetaldehyde. Furthermore, mercaptans [3] and ethyl esters of 2-, 3-, and 4-methylpentanoic acid are characteristic constituents [4]. These distinctive aromatic components contribute to the complex and captivating sensory profile of noble rot wine. The eastern foothills of Helan Mountain (Ningxia, China) are located in a \"golden\" wine grape growing belt at 38\({}^{\circ}\) N latitude. Due to the mountain barrier and the Yellow River irrigation system, this area has become important for producing high-quality wine in China [5]. Key features include more than 3000 h of sunshine per year and a significant difference in temperature between day and night (10-15 \({}^{\circ}\)C). In addition to cultivating international varieties of grapes, the region has explored the brewing potential of special varieties, such as Petit Manseng. This variety can be used to produce high-quality sweet wines because it ripens late (harvesting can be delayed until the end of November), maintains high sugar and acidity levels, and exhibits strong resistance to disease. However, gray mold infestation has been observed as spots on the surface of fruits during the ripening period. As pathogenic bacteria continue to proliferate during ripening, infested parts may crumple, and the skin of diseased fruits can become shriveled. However, the flesh tissue is usually free from lesions and retains its high concentration of sugars. These characteristics are typical of noble rot grapes used for brewing, and Ningxia has the conditions necessary for brewing noble rot wines [6]. However, a better understanding of how _Botrytis cinerea_ infestation affects the flavor of wines produced from Petit Manseng grapes grown in Ningxia is needed. The aim of this study is to systematically investigate the effects of different degrees of noble rot (Botrytis cinerea) infestation (no infestation, mild infestation, severe infestation) on the flavor of Petit Manseng wines from the Helan Mountain East Foothill region, through identifying and quantifying volatile aroma compounds in wines produced from grapes with varying infestation degrees using HS-SPME-GC-MS and electronic nose, evaluating sensory characteristics (e.g., floral, fruits, honey notes) via trained panelists, determining the key aroma compounds associated with superior flavor in these wines, and providing a scientific basis for optimizing harvest and winemaking strategies for high-quality Petit Manseng noble rot wines in this region.