## 3 Results and Discussion
### Detection of the Presence/Absence of Gluten in Commercial Hydrated Cassava Starch  
Following the partial characterization, the samples were analyzed for the presence or absence of gluten using a rapid gluten protein test kit. Gluten was detected in 5.71% of the evaluated samples, as illustrated in Figure 2. Among the samples that tested positive for gluten, there were products that, in addition to cassava starch, contained other plant-based ingredients, such as beetroot. Including non-mandatory ingredients can represent a potential source of contamination, as it introduces additional variables into the process that need to be strictly controlled to prevent gluten cross-contamination. In such cases, it is essential to use certified suppliers and ensure that the production process flow is well-established, with rigorous measures in place to prevent the presence of this allergen in the final products. Figure 1: Principal components analysis (PCA) for particle size distribution. Active variables (\(\bullet\)) and observations (\(\bullet\)). Samples highlighted with the same color indicate hydrated cassava starch produced by the same manufacturer. Figure 2: Presence of gluten in commercial hydrated cassava starch samples. Gluten-free (\(\bullet\)) and with gluten (\(\bullet\)). Notably, despite the detection of gluten in these samples, all commercially available products were labeled with the claim \"gluten-free\" on their packaging. This discrepancy raises significant concerns regarding the accuracy of labeling and potential risks to individuals with celiac disease or gluten sensitivity, as even trace amounts of gluten can trigger severe adverse reactions in this population. The allergenic potential of gluten present in food varies from person to person and may trigger different symptoms depending on factors such as age group and pre-existing conditions. Therefore, it is important not only to establish the presence of gluten but also to determine the individual threshold of tolerance through personalized diagnostics. This approach supports a more precise and balanced dietary management, avoiding unnecessary food restrictions [55]. Considering that the test used has a detection limit of 5 ppm, any positive result may be relevant, especially for individuals with celiac disease, whose tolerated daily intake ranges from 10 to 100 mg. For wheat-allergic individuals, particularly children, reactions can be triggered by doses in the low milligram range [55]. Celiac disease affects around 3% of the global population [17] and is triggered by gluten intake, leading to immune-related damage in the small intestine [18; 19]. This results in poor nutrient absorption and common symptoms like weight loss, abdominal pain, and diarrhea. It can also cause atypical symptoms such as anemia, osteoporosis, infertility, and neurological issues [20; 21; 22]. Despite being inherently gluten-free, hydrated cassava starch is susceptible to cross-contamination when processed in facilities lacking stringent control measures and dedicated gluten-free protocols. This risk is heightened in environments where processing equipment or production lines are shared with gluten-containing products, potentially leading to unintentional gluten exposure. Inadequate separation and insufficient enforcement of hygiene standards contribute significantly to this hazard. Therefore, comprehensive monitoring and strict adherence to contamination prevention protocols are critical to maintaining the gluten-free integrity of cassava starch and ensuring its safety for individuals with gluten-related disorders [24; 26]. Studies from different countries have reported concerning gluten contamination levels in products labeled \"gluten-free.\" In Mexico, detectable amounts of gluten were found in 20% of evaluated products claiming to be \"gluten-free\" [56]. Similarly, in India, 10% of \"gluten-free\" labeled products tested positive for gluten, including naturally gluten-free items like hydrated cassava starch, where approximately 12% showed gluten contamination [57].