Speaker: Dr. Bart Nicolai. Pear fruit are typically stored under controlled atmosphere (CA) conditions. When the O2 concentration is too low or the CO2 concentration too high, browning disorders may develop. The current hypothesis is that the diffusion resistance of the tissue limits the O2 supply and causes the respiration metabolism to stall and fermentation to be upregulated. The low energy yield of the fermentation pathways causes an energy crisis, and essential maintenance processes such as cell membrane repair are no longer possible. Eventually cells die and phenolic substrates are oxidised to brown colored patches. In this presentation Dr. Nicolai will discuss how gas transport in fruit can be studied by both experimental and in silico techniques. He will show how X-ray microtomography techniques can be used to create 3-D representations of pear tissue at micrometer scale and how its microstructure affects gas transport. As the respiration and fermentation pathways provide the driving force for gas transport, the development of browning disorders of pear fruit is, hence, determined to a large extent by its microstructure and respiratory activity. This knowledge may inspire the development of future sensors to measure the susceptibility of batches of pear fruit to CA related browning disorders and facilitate cool store management.
