Impact of accelerated aging on lipid reserves, physiological and biophysical behavior in chia (Salvia hispanica L.) seeds

RODRIGUEZ M. E.; PEREZ E. E.; SCHNEIDER-TEXIERA A.; DELADINO L.; IXTAINA V. Y,

Lima

Congreso; 6th Ia ValSe-Food Network International Congress; 2024

la ValSe Food_CSIC_Universidad de Lima

The accelerated aging test is crucial for evaluating seed quality and longevity, simulating adverse storage conditions to assess conservation potential. This study investigated the effect of accelerated aging on the physiological, biochemical, and biophysical aspects of chia seeds. The accelerated aging revealed notable stress tolerance in white (WN) and mixed (MN) chia seed genotypes. Germination power decreased from 100 % to 0 % over 56 days, with reductions in radicle and hypocotyl length, increased abnormal seedlings, and dead seeds. Regarding seed lipid fraction, peroxide content significantly increased, ranging from 1.81 to 6.50 meq/kg for WN and 0.85 to 3.22 meq/kg for MN genotypes. Free fatty acids rose considerably, from 0.41 % to 2.95 % oleic acid for WN and 0.40 % to 3.18 % for MN. Total tocopherol content significantly decreased in both genotypes, altering the balance between pro- and antioxidant processes. Also, an increase in saturated fatty acids and a decrease in unsaturated ones were recorded. These changes compromise the membrane fluidity and permeability, reflected in increased electrical conductivity, ranging from 129.26 to 399.25 μScm-1g-1 for WN, and 177.06 to 500.81 μScm-1g-1 for MN. The DSC technique provided consistent information about these changes. Regarding FTIR analysis, two components distinguished aged from non-aged genotypes, accounting for 91 % of the variability. Vibrations at 3010, 2928, and 720cm-1, linked to lipids, enabled rapid detection of deterioration. These findings highlight the impact of oxidative stress on the viability and quality of chia seeds.