The WVTR values show wide differences among coating formulas, which are related to the chitosan derivative type and MFC presence (Figure 5). Single-component coating formulas based on the ACh and CCh give the lowest WVTR values, with a reduction of about 30% compared to the reference, but no significant reduction is registered in the case of QCh coating. Therefore, the CCh and ACh derivatives have the ability to generate uniform films, with compact structures at relatively low coating weight (2) g/m²). Unlike CCh coating, the MFC coating had no significant influence on the WVTR, though both are hydrophilic and have similar values of the contact angle and Cobb60 index. In fact, all coatings containing MFC (mixture or separate layers) have higher WVTR values than individual ChD coatings. This could be explained by the differences of surface structure observed by SEM analysis. For example, the micrographs of