Considering the variation of free and total FBs after thermal
treatments, H13 and H16 showed a slight reduction in quantified
free and total FBs compared to the untreated samples, probably
due to the natural variability between grain samples. Comparable
values in FBs free and FBs total were found in H3 after drying at
95 C and in H8 after drying at 70 C; both free and total FBs
increased, more markedly free FBs, in the other drying conditions
(Fig. 1). Increases in free and total FBs were noticed in H15, after
both drying treatments, mainly with 70 C 24 h. The increase
was more relevant in H14, especially for the free forms, with 46
times and 16 times the initial amount measured when dried at
95 C and 70 C, respectively (Fig. 1). The rate free/total FBs
increased after the thermal treatment, moving from a mean of
0.40e0.71 and 0.53, respectively with the exposure to
70 C 24 h or 95 C 9 h. Free forms became dominant in 3 out
of the 6 hybrids considered; the opposite was observed in H16
(rate ¼ 0.27), with hidden forms largely dominant, H13
(rate ¼ 0.47) and H14 (rate ¼ 0.49), with a balance between the 2
forms, when exposed to 95 C.