Carotenoid stability in grains of maize hybrids compared to complete feeds for laying hens following preparation and storage

• Maize hybrid affected stability of carotenoids during storage • Degradation rates were up to three fold higher in complete feeds than in whole grains • LUT and ZEA showed the highest stability, followed by βC, βCX and αCX • Carotenoid stability is an essential criterion for the use of maize as a source of pigment in hen diet Yellow maize grain is an important source of carotenoids for yolk pigmentation, but carotenoids are susceptible to degradation during storage of feeds for laying hens. In this study, the stability of carotenoids [lutein (LUT), zeaxanthin (ZEA), α- and β-cryptoxanthin (αCX, βCX), β-carotene (βC) and total carotenoids (TC)] in the grains of maize hybrids (14 dent and 1 semi-flint) was compared with that in complete feeds after preparation and storage for 84 days at 20±2°C. Depending on hybrid, the TC retention was higher in maize grains (84.2 – 95.8%) compared to the complete feeds (67.2 – 84.2%). LUT was the most stable carotenoid in grains as well as in complete feeds (1.06 vs. 3.08 × 10 3 day -1 , respectively), followed by ZEA (1.18 vs. 3.11 × 10 3 day -1 , respectively). The βC and βCX showed similar stability in maize grains (on average 2.05 and 2.13 × 10 3 day -1 , respectively) and complete feeds (on average 4.18 and 4.05 × 10 3 day -1 , respectively), whereas αCX was the most susceptible to degradation. However, some hybrids with high carotenoid stability during grain storage showed opposite responses after preparation and storage of complete feeds, and vice versa. Interestingly, semi-flint hybrid was characterised by relatively low carotenoid retention in both forms. Overall, carotenoid degradation increased after preparation and storage of complete feeds, while tested hybrids differed in their stability for all carotenoids.