## 4 Discussion  
Physicochemical characteristics such as moisture content, water activity, and color are important for NCS because these traits influence consumer sensory preferences [8; 21]. The moisture content of the NCS products obtained at different evaporation temperatures was below 6% (Table 2). These values fall within a similar range as those reported for commercial unrefined sugars in previous studies [1; 22]. The water activity of NCS produced with an evaporation temperature of 140 \({}^{\circ}\)C was markedly below 0.4, suggesting potent long-term storage stability, equivalent to dried foods [9; 23]. Moreover, the water activity level of  
Figure 4: Heatmap visualization of Pearson’s correlation between physicochemical characteristics and Maillard reaction products (MRPs) of non-centrifugal cane sugar (NCS) obtained at different evaporation temperatures. Asterisks indicate a significant correlation; * \(p<0.05\); * \(p<0.01\). MRP1: 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one; MRP2: 2-furanmethanol; MRP3: 2-methylpyrazine; MRP4: 2.5-dimethylpyrazine; MRP5: 2.6-dimethylpyrazine; MRP6: 5-methyl-2-furanmethanol; MRP7: 2-acetylpyrrole; PE: polyethylene membrane extraction; RAS: retronasal aroma simulator extraction. NCS obtained at the lowest evaporation temperature of 120 \({}^{\circ}\)C was 0.63, which can be considered an adverse condition for the growth of spoilage microbes [9; 24]. Therefore, this thermal process was adequate to preserve the product against potential microbial spoilage. The values of these physical traits decreased as the evaporation temperature increased, indicating the importance of the thermal process in NCS production. This thermal process plays a crucial role in evaporating moisture from the solidified products, confirming the widely accepted notion that thermal energy influences the mass balance in the evaporation process [25; 26]. Temperature adjustments during the evaporation process also affected the color of the NCS; the solidified products became darker as the temperature increased, as evident from the visual and color indicators (Figure 1b; Table 2). This color development could be caused by the accumulation of brown pigment substances in the NCS, which are formed through Maillard reactions and caramelization during heating [2; 3; 27]. The color indicator data, which are numerical representations of color properties such as L*a*b*c color spaces and ICUMA values, are very important for the evaluation of NCS. By measuring these indicators, manufacturers can ensure that they consistently meet the desired color specifications, which are important for the appearance, acceptance, and marketability of these products [2; 3; 22]. These physicochemical data can also be used to monitor the effects of processing, storage, and other factors on the color of NCS and their derived food and beverage products. This enables manufacturers to make the necessary adjustments to ensure that the final products meet their desired quality standards [3; 19; 21]. The Maillard reaction, which occurs rapidly during the final heating stage of the evaporation process, is closely related to the unique color, taste, and aroma of NCS [8; 10; 22]. The rate of the Maillard reaction is temperature-dependent. An increase in temperature can enhance the reaction rate because it influences the activation energy required for the reaction to occur [28; 29]. At higher temperatures, the precursor molecules (reducing sugars and amino acids) have greater kinetic energies, which enables them to overcome the activation energy barrier and react more rapidly [29; 30]. As a result, the Maillard reaction can occur more quickly, leading to a higher formation of MRPs. This phenomenon can account for the increased generation of aroma compounds, such as pyranone, furan, pyrazine, and pyrrole (Figures 2 and 3), in the NCS obtained with high evaporation temperatures. Moreover, the PE and RAS extraction systems showed different compositions of volatile MRPs.