UNIQUE FEATURES of DCS automatic
Daily measurement of fermentation / respiration = FQ
Our ethanol-analyser is measuring a sample of 20 kg fruit on a daily basis without interfering the CA- or cooling-installation. You don't have to shut down the cooling or CA-system to measure the ethanol. During the measurement-cycle, data is collected concerning the level of fermentation and respiration. The ratio calculated from both parameters is projected as the FQ, fermentation coefficient. Compared to the RQ (respiration coefficient), the FQ is much more accurate and reliable.
aerobic versus anaerobic fermentation
Ethanol is the result of fermentation and the only marker to determine fermentation. Fermentation can occur under aerobic or anaerobic conditions. Aerobic fermentation is the result of decay, mould or damaged tissue and as a background-noise always present in a fruitstorage-room. By measuring the ethanolproduction and the respiration our DCS automatic system is able to determine whether the fermentation is anaerobic or aerobic, caused by bad fruits or damaged tissue. The high-sensitive ethanol-sensor is able to detect even 1 rotten apple in a sample of 120 fruits. External as well as internal damaged tissue can be determined. With these measurements the client has essential early-stage information regarding the physical quality of the fruit. In case of determination of early-stage internal or external defects, the client can minimize storage-losses to a minimum.
Aerobic fermentation: case 1
Van Riel in the Netherlands with Elstar apples, slow increase of ethanol by 0,1-0,2 mg./100gr per day from 0,75 mg up to 1,75 mg. After removal of one rotten apple the ethanol-level inmediately decreased to normal back-ground level.
Aerobic fermentation: case 2
Hoogsteeger in the Netherlands with Jonagold apples. DCS system noticed a continuous slow increase of 0,1 - 0,2 mg ethanol per day upto a level of 3,5 mg/100 gr fruit. The grower did three tests by cutting the sample of the measuringbox and detected 10-20% of the apples infected by a fungis. After inspection of the apples in the storage-room he came with the result of 20% infected apples. Because of the early-stage of the infection the client decided to market the fruit earlier as planned and could avoid serious storage-losses. The infectrion was caused by a delayed treatment with a fungicide due to bad weather conditions.
Aerobic fermentation: case 3
Peeters in the Netherlands with Elstar apples, slow increase of ethanol by 0,1-0,2 mg./100gr per day from 0,75 mg up to 1,75 mg. After removal of one rotten apple the ethanol-level inmediately decreased to normal back-ground level.
Large replaceable sample
One DCS Automatic system can measure two CA-storagerooms. The measuring-boxes are integrated (build-in) and can contain 20 kg of fruit each, so 100-120 apples depending the size of the apples. The measuring-boxes are closed by a transparant lid and during DCA-storage the boxes can be opened for inspection or to replace the sample. The lid is transparent for easy visual inspection and has a special isolated layer to prevent energy-input from environment. A special circluation system ensures exact conditions as in the storage-room itself. Each lid can be covered with a polystyrene cover to minimize temperature influcences.
Since 1997 the Wageningen Univeristy FBR uses the fruitflesh analysis to determine the level of ethanol. Samples of fruits (9 apples) are taken on a regulary basis (3 analyses per saison) to determine the ethanol level to advise on oxygen-levels for DCA.storages. This analysis, DCS manual, is very labour intensive, destructive and not appropiate to determine the critical oxygen-level on a daily basis. In close cooperation with WUR FBR and EMS, Storex has delevoped a system to measure the ethanol-level on a ppb-level in the headspace of a measuring-box. This analysis is non-destructive, daily and measurments can be reproduced time over time. The system to analyze the ethanol-level is called DCS automatic.
No interference with ripening blockers
Ripening blockers are used as a postharvest treatment in CA-rooms to minimize c.q. to block the respiration. By minimizing the respiration, the process of ripening is reduced to a minimum. Ripening blockers, like SmartFresh, are used worldwide and on many products like apples, pears and kiwis.
To measure the ethanol in the fruit, many commercial systems use sensors based on fluoriscency. HarvestWatch, Fruitobserver and the Ethanolsensor of Frigotec uses this technique to determine indirectly the ethanol-level in the fruitflesh.
A high level of ethanol inside the fruitflesh changes the color of the skin of the fruit. The color-change is predictable in case no ripening-blockers are used. A scientific study in Poland showed that if a ripening blocker is used then the ethanol-level is more difficult to predict.