[4-1600-C] Postharvest/Food Technology and Process Engineering (4)

[4-1600-C-03] Modeling The Ripening Behavior of Mature Green Tomato at Different Storage Temperatures

*Drupadi Ciptaningtyas^1,2, Wakana Kagoshima³, Rei Iida¹, Hitomi Umehara¹, Masafumi Johkan¹, Takeo Shiina¹ (1. Graduate School of Horticulture, Chiba University(Japan), 2. Faculty of Agro-industrial Technology, Universitas Padjadjaran(Indonesia), 3. Faculty of Horticulture, Chiba University(Japan))

キーワード：mature green stage, modeling, red color development, ripening, tomato

Mature green tomato is a tomato that is physiologically mature but pre-ripe and has a green and slightly white color in appearance. In many countries except Japan, tomatoes are harvested in the mature green stage of development for commercial purpose. Some researcher recommends the mature green stage of development for the harvesting time of typically red tomato. It was studied that harvesting tomato at the mature green stage can extend the shelf life of the tomato which is desirable in the long-distance distribution and long-term storage. The previous study has proven that even though every individual tomato that was stored at the same storage temperature has a different onset in the ripening indicator, but the trend was almost the same and it is possible to make a model of it. This study was aimed to observe the red color development of mature green tomato during ripening while the lag time of red color development for tomato stored at different storage temperature conditions was being observed. Furthermore, the standard curve for predicting the red color development based on the storage period of mature green tomato (cv. Momotaro York) at different storage temperature will also be developed. Five storage temperatures (12, 15, 20, 25, and 30 °C) were assigned to hold 5 tomatoes (cv. Momotaro York), respectively until every tomato reached the fully ripening stage. Red color development was determined by measuring the CIE a* value of 7 spots in the surface area of the tomato. Lag time will be determined based on the breaker stage of development of the tomato. The rate of red color development will be determined by the curve showing the relationship between the CIE a* value and storage period. Furthermore, the standard curve for predicting the red color development will be developed according to the relationship between CIE a* value and storage period that was approached by the curve fitting method to sigmoid function. The preliminary study showed that the lag time of tomato was a temperature dependent. The higher the temperature, the shorter the lag time and vice versa. This trend was also observed for the rate of red color development. By using these data including the data from the ongoing experiment, standard curves of red color development of mature green tomato during ripening at different storage temperature conditions will be developed. It will enable us to simply predict the ripening stage of tomato harvested at the mature green stage based on the temperature and storage period.