Modification of cell wall composition of apricots (Prunus armeniaca) during drying and storage under modified atmospheres

Fresh apricots (Prunus armeniaca) were treated with Na2S2O5 and acetic acid solutions before dehydration. Dehydrated apricots were stored at 25 degree s C in five different modified atmospheres (MAs) [100% N-2 (N), 20% CO2 and 80% N-2 (2C8N), 40% CO2 and 60% N-2 (4C6N), 60% CO2 and 40% N-2 (6C4N), 10 0% CO2 (C)]. An additional sample was stared at 25 degrees C under air. The yield of apricot cell wall material decreased substantially during drying pretreatments and also during dehydration, by 9.5 and 4.7%, respectively. I n particular, acetic acid solubilized a large amount of pectic polysacchari des. Further degradation of pectic substances was produced during drying, p robably due to the high temperature used. However, MAs retarded browning in comparison to the sample stored under air. The content of SO2 decreased ma rkedly for the sample stored in air, whereas gradual losses were observed f or MA samples. In general, samples stored under atmospheres containing rela tively low percentages of CO2 (20 and 40%) and N-2 showed minor disruption of cell wall components and maintained better the initial characteristics o f dehydrated apricots.