Kernel properties related to carotenoid release during in vitro gastrointestinal digestion in commercial dent maize hybrids

Relationship of Physical Properties and Macronutrient Composition with Carotenoid Profile in Maize Hybrids

“…Smaller and rounder kernels usually belong to hybrids of higher kernel hardness [41], such that the kernel size can indirectly indicate the nutritional value of maize. Hybrid 9 showed the lowest sphericity value (0.62), while hybrid 11 showed the highest value (0.70), and this range was within the range previously reported as 0.53 to 0.77 [22,40,41]. In addition, the sphericity of the tested hybrids increased with decreasing kernel height (r = −0.758, p < 0.001) and increasing length and thickness (r = 0.271 and 0.352, respectively, p < 0.05).…”

“…The kernels had an average height, length and thickness of 12.52, 8.42 and 5.09 mm, respectively. The results for the determined kernel dimensions are comparable to other studies [22,38,40], in which the height of the kernels ranged between 10.56 and 15.05 mm, the length between 7.23 and 10.44 mm and the thickness between 3.51 and 5.42 mm. Smaller and rounder kernels usually belong to hybrids of higher kernel hardness [41], such that the kernel size can indirectly indicate the nutritional value of maize.…”

“…The C/F ratio showed considerable variability, ranging from 0.26 to 0.72. Regardless of this variability, the results for these three parameters were within the range of 103 commercial maize hybrids tested (1.77-3.97 s, 86-114 mm and 0.17-0.83, respectively) [22]. Bulk density is considered a simple method to indicate kernel hardness [11], and the correlations obtained in the present study (0.725, −0.755 and 0.717 for time required to grind 17 mL of grits, height of the grits in the grinding column and C/F in grits, p < 0.001) were in accordance with previous studies [40,42].…”

“…In addition, the color parameters according to CIE L*a*b* [23] are listed in Table 2. The tested hybrids were selected based on physicochemical properties, carotenoid profile and in vitro carotenoid bioaccessibility from 103 commercial maize hybrids from 9 seed companies (Table 1) available on the market [22]. Selection was conducted to obtain a wide range of these properties to ensure the variability of commercial maize hybrids regardless of the seed company.…”

“…Since a more vitreous endosperm has a greater ability to store zeins [20], the different protein composition between hard and soft kernels may affect their carotenoid profile [8,13]. Nevertheless, differences in chemical composition have been linked to the in vitro carotenoid digestibility of maize kernels [22], suggesting that the chemical composition may be related to the carotenoid profile of maize hybrids.…”