ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Control of postharvest decay in organically grown apple cultivars by hot water dipping

Maxin P.; Klopp K.; Huyskens-Keil S. and Ebert G.

5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.113

2004

บทคัดย่อ

Organically grown apples (Malus xdomestica Borkh.) suffer from up to 30% decay during storage due to the lack of chemical fungicide treatments. Preliminary hot water dipping of apples had shown that a water temperature about 50°C and dipping times from 60s up to 180s were required to inhibit Gloeosporium rot (Pezicula alba, P. malicortis) o­n apples.

In the present investigation different rages of tempertures (49°C, 51°C, 53°C) and time periods (60s, 120s, 180s) were studies to detemine suitable hot water treatments for five apple cultivars, i.e. ‘Boskoop’, ‘Elstar’, ‘Jonagored’, ‘Ingrid Marie’, ‘Topaz’, especially to evaluate fruit quality (firmness, skin symptoms) and decay pathogens (Botrytis cinerea, Penicillium ssp., Monilia fructigena, Nectria galligena and Fusarium ssp.).

Monilia fructigena was reduced to 83% in the cultivar ‘Ingrid Marie’ by the hot water treatment at 53°C and 180s dipping time. With this treatment Gloeosporium rot was reduced to 92%. The incidence of Nectria galligena increased in the 60s duration at all temperatures. Skin symptoms occurred o­n ‘Ingrid Marid’, ‘Boskoop’ and ‘Elstar’, at 51°C with 180s, 53°C with 120s, 53°C with 180s, respectively. Heat treatments had no effect o­n fruit firmness in all cultivars.

From the present results it is concluded that for the reduction of postharvest decay the heat treatment “180s at 53°C” can be recommended for all apple cultivars, For cultivars with a high sensitivity to skin symptoms it is recommended to dip for 120s or 180s at the maximum cultivar specific temperature showing no symptoms.