awad, M., EI-Dengawy, E. (2006). INFLUENCES OF SOME POST-HARVEST DIPPING TREATMENTS ON GUAVA (Psidium guajava L.) FRUIT QUALITY AND THE INCIDENCE OF SKIN BROWNING DURING SHELF LIFE. Journal of Plant Production, 31(1), 383-391. doi: 10.21608/jpp.2006.235708
mohamed awad; E. F. A. EI-Dengawy. "INFLUENCES OF SOME POST-HARVEST DIPPING TREATMENTS ON GUAVA (Psidium guajava L.) FRUIT QUALITY AND THE INCIDENCE OF SKIN BROWNING DURING SHELF LIFE". Journal of Plant Production, 31, 1, 2006, 383-391. doi: 10.21608/jpp.2006.235708
awad, M., EI-Dengawy, E. (2006). 'INFLUENCES OF SOME POST-HARVEST DIPPING TREATMENTS ON GUAVA (Psidium guajava L.) FRUIT QUALITY AND THE INCIDENCE OF SKIN BROWNING DURING SHELF LIFE', Journal of Plant Production, 31(1), pp. 383-391. doi: 10.21608/jpp.2006.235708
awad, M., EI-Dengawy, E. INFLUENCES OF SOME POST-HARVEST DIPPING TREATMENTS ON GUAVA (Psidium guajava L.) FRUIT QUALITY AND THE INCIDENCE OF SKIN BROWNING DURING SHELF LIFE. Journal of Plant Production, 2006; 31(1): 383-391. doi: 10.21608/jpp.2006.235708
INFLUENCES OF SOME POST-HARVEST DIPPING TREATMENTS ON GUAVA (Psidium guajava L.) FRUIT QUALITY AND THE INCIDENCE OF SKIN BROWNING DURING SHELF LIFE
2Pomology Department, Faculty of Agriculture, Mansoura University 35516, EI-Mansoura/Egypt
Abstract
During 2002 and 2003 seasons the influences of post-harvest dipping treatments of 500 ppm boron (boric acid), 4.0% calcium chloride, 0.25% zinc sulfate, 10 mM sodium benzoate, 2.0 mM salicylic acid, 2.0 mM acetyl salicylic acid, 200 ppm ABG-3168 (ReTain), 0.5% plantacur-E (25.0% alpha-tocopherol) and 3.0% corn starch for 3 min on mature seedy "Balady" guava fruit quality and the incidence of skin browning during 4-days of shelf life at 25°C±3 and 50-60% RH were studied. The results showed that most fruit quality parameters were significantly influenced by the applied treatments. Except the ABG treatment, all the other treatments significantly decreased the incidence of skin browning compared with the control. In this respect, the most effective treatment was sodium benzoate followed by acetyl salicylic acid, s.Jicylic acid, and boron treatments. Except the plantacur-E treatment, all the other treatments significantly decreased the weight loss of fruit compared with the control. Acetyl salicylic acid, sodium benzoate, boron, and calcium chloride treated fruits were significantly firmer than the control. The concentration of fruit acidity was greatly increased in all the treatments during 4-days of shelf life compared to the initial concentration. Acetyl salicylic acid treated fruit contained the highest acidity concentration followed by zinc sulfate and that was significantly higher than all other treatments. Calcium chloride treated fruit contained a significant higher concentration of TSS than all other treatments. There were clear decreases in the concentration of vitamin C (about 24% in the control) during 4-days of shelf life in all the treatments compared to the initial concentration. Boron, calcium chloride, acetyl salicylic acid, zinc sulfate, sodium benzoate, corn, and plantacur-E treated fruit showed Significant higher concentrations of vitamin C than the control. However, salicylic acid and ABG treatments significantly decreased the concentration of vitamin C compared with the control. Surprisingly, there was almost no response of guava fruit to ABG application despite, it is a climacteric fruit type. The results concluded that some of the used compounds (especially sodium benzoate, acetyl salicylic acid, salicylic acid, boron, and zinc sulfate) showed clear effects on maintaining quality and decreasing the incidence of browning. However, non of these compounds, at the used concentrations, could completely eliminate the incidence of browning during shelf life. Applying higher concentrations of these compounds might further inhibit browning and better maintain quality of guava fruit during shelf life.