# Loss of Vitamin E While Baking and Heating French Fries
## 3 Results and Discussion
### Content of Tocochromanols in Frozen Pre-Fried French Fries and Factors Affecting It
In all the cases, the content of the analytes in the analyzed pre-fried French fries (i.e., \(\alpha\)-tocopherol, total docochromanols and vitamin E content in \(\alpha\)-TE) increased with the fat content (if its content had a statistically significant effect on the analyte) and the linoleic acid content, and decreased with the total content of saturated fatty acids (if their content had a statistically significant effect on the analyte). This is logical and corresponds with the previous literature (see below). A positive correlation between linoleic acid and \(\alpha\)-tocopherol (\(p<0.05\)) and \(\gamma\)-tocopherol was found in the content of individual tocopherols under the different heat-free treatments for fats and oils [32]. Unsaturated vegetable oils generally have a higher tocopherol content than saturated oils, which is related to the main biochemical function of the tocopherols in plants, i.e., the protection of polyunsaturated fatty acids against peroxidation [33]. Furthermore, during repeated frying, the tocopherols decreased faster in less unsaturated fats and oils [31]; as a result, found in fats and oils after frying under commercial conditions was the presence of typically higher levels of vitamin E in highly unsaturated vegetable oils (i.e., sunflower, cottonseed and corn oil) than in less unsaturated vegetable oils (i.e., palm kernel oil and partially hydrogenated soybean oil) [34]. The effect of the oil used on the vitamin E content in fried foods is derived from previous literature [35] and has been confirmed in a study of fried French fries from various restaurants and fast food establishments, fried potato chips and other similar fried snack products [19]. This can also be seen in Figure 1, which compares the vitamin E content of the analyzed frozen pre-fried French fries depending on the frying medium used. \begin{table}
\begin{tabular}{l c c c} \hline  & \(\alpha\)-T & **T + T3** & **Vitamin E** \\ \hline The whole model (see Table 2) & 0.917 & 0.965 & 0.954 \\ Linoleic acid * & 0.917 & 0.915 & 0.919 \\ Saturated fatty acids * & - & 0.688 & 0.716 \\ Fat content * & - & 0.786 & 0.706 \\ \hline \end{tabular}  
* A high coefficient of determination indicates the high influence of the relevant factor (independent variable) on a given dependent variable (i.e., the content of toochromanols or vitamin E) [30].  
\end{table} 
Table 3: Determination coefficients characterizing the effect of selected factors on the content of toochromanols and vitamin E in commercially available frozen pre-fried French fries. Losses of Tocochromanols While Preparing French Fries Using Commercially Available Pre-Fried Frozen Products by Baking Them in Conventional and Microwave Ovens  
Table 4 documents the content of the individual tocochromanols, the total tocochromanol content and the vitamin E content in the \(\alpha\)-tocopherol equivalents analyzed in the baked French fries. The baking method used did not have a statistically significant effect on the content of any of the monitored analytes (\(p<0.01\)). However, the content of the monitored analytes was significantly higher among baked French fries than in the pre-fried frozen products (compare Tables 1 and 4). Significant moisture losses occurred during baking (irrespective of the appliance used and the method of heating), ranging from 22.0 to 57.3% of the weight of the starting pre-fried frozen products (on average 39.5%). If these weight losses while baking French fries were accounted for and the results of all baking methods were processed together, the \(\gamma\)-T, \(\delta\)-T, \(\gamma\)-T3 and \(\delta\)-T3 losses were statically insignificant, while losses of \(\alpha\)-T, \(\alpha\)-T3, total tocochromanols and the vitamin E content in \(\alpha\)-tocopherol equivalents were statistically significant (\(p<0.01\)).