Nondestructive Determination of Components on Texture of Squash Fruit (Cucurbuta maxima Duch.) using Near Infrared Spectroscopy

Abstract

　Components, that affected the mealy texture of squash fruit (Cucurbita maxima Duch.), were measured non-destructively using near infrared spectroscopy, and changes during storage were investigated. The texture of squash fruit was evaluated by measuring the firmness of steamed squash fruit mesocarp. Thus, the delimiting firmness was determined to be 1.6 N, which distinguished mealiness or stickiness. A strong positive correlation coefficient of 0.92 was found between dry matter content and fruit firmness.

　The dry matter content of squash fruit was measured non-destructively by near infrared spectroscopy, and a calibration model was determined, for practical use. When the dry matter content of squash fruit measured non-destructively at harvest-time was over 19 %, a mealy texture was confirmed. In addition, if the dry matter content of squash fruits measured non-destructively before storage was more than 25 % or 30 %, the fruits could maintain firmness for approximately 30 or 60 days, respectively. The results suggest the possibility of maintaining the mealy texture in squash fruits after 30 storage days in fruit that has a dry matter content above 25 % at harvest-time.