Cell wall polysaccharides degradation and ultrastructure modification of apricot during storage at a near freezing temperature

[Display omitted] •NFT storage suppressed the solubilization of NSP and cellulose.•The loss of side chains in CSP made the main contribution to apricot softening.•The loss of side chain in CSP was suppressed by NFT storage.•NFT storage delayed pectin degradation and middle lamella dissolution of apricot.•The inhibition of ethylene is the mechanism of NFT on delaying apricot softening. The effects of near freezing temperature (NFT) storage at −1.9 °C on cell wall degradation of ‘Shushanggan’ apricot was studied comparing to 0 °C and 5 °C storage. Our results indicated that NFT storage strongly inhibited the solubilization of Na2CO3-soluble pectin and cellulose, by the suppression of cell wall modifying enzymes (polygalacturonase, β-Galactosidase, pectin methyl esterase and cellulase) and related genes expressions. The loss of side chains was the main modification in CDTA (Cyclohexane-diamine-tetraacetic Acid)-soluble pectin during storage and made the main contribution to the softening of apricot, while the loss of side chain was suppressed by NFT storage. Microscopic observation showed that NFT storage delayed the degradation of pectin fraction and protected cell wall structure from loosing. This study proves that NFT storage is an effective technology to suppress the cell wall polysaccharides degradation and ultrastructure modification of apricot.