Evolution of postharvest maturity of tomatoes grown on different substrates: non-destructive firmness and colour measurements.
Busscher, R. de, Vandewalle, X., Schrevens, E. and Baerdemaeker, J. de
COST 94. The post-harvest treatment of fruit and vegetables: quality riteria. Proceedings of a workshop, Bled, Slovenia, 19-21 Apr. 1994. p 69-79.
1994
บทคัดย่อ
ABSTRACT :
Tomato plants (cv. Trust) were grown in the autumn in nutrient film technique (NFT), or on rockwool or polyurethane substrates. The saturated moisture contents of the rockwool and polyurethane substrates were monitored and controlled (70% moisture content on a volume basis for the rockwool and 50% for polyurethane) on the basis of thermal conductivity measurements of the substrate. Over a period of 4 weeks, 368 fruits were picked and stored at 20 deg C and 70% RH. Firmness and colour were measured daily for 6 days. Firmness was measured using the acoustic impulse response technique and colour distribution information was obtained from digitized video images. Fruits from plants grown on the polyurethane substrate remained firmer and showed slower colour development during storage than those grown on rockwool or in NFT. In a second experiment, tomato plants were grown on rockwool mats with an actively controlled water supply, set up using the Active Drain System (ADS) combined with thermal conduct
ivity sensing. The ADS collects drainwater and controls the moisture content in the mats. Fruits from plants grown under saturated (70-80% volume) and 30% moisture content on a volume basis were compared for firmness and colour development after picking. Low substrate moisture content resulted in slightly greater firmness and significantly delayed colour development.