Nondestructive determination of flesh color in clingstone peaches

• Published in: Journal of food engineering Vol. 116; no. 4; pp. 920 - 925
• Main Authors: Slaughter, D.C., Crisosto, C.H., Tiwari, G.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-06-2013
• Subjects: Canning; Clingstone peach; Color; Flesh color; Grounds; Infrared; Nondestructive; On-line systems; Peaches; Stations; Tasks; Visible–NIR spectroscopy; Nondestructive; Flesh color; Clingstone peach; Visible–NIR spectroscopy
• ISSN: 0260-8774; 1873-5770
• DOI: 10.1016/j.jfoodeng.2013.01.007

► Skin color was uncorrelated to flesh color in peaches with skin hue angles below 70°. ► Mean flesh reflectance at 675nm (chlorophyll band) was related to flesh hue only for higher hues. ► Skin reflectance was not needed when predicting flesh hue by interactance measurements. ► Nondestructive interactance at two visible wavebands can predict peach flesh hue (r=0.92).
A nondestructive optical method, based upon visible and near infrared interactance spectroscopy, was developed for rapid determination of flesh color in clingstone peaches. Flesh color is currently used by the Californian canning peach industry as a destructive maturity index for clingstone peaches inspected at harvest and as a predictor of sensory flavor quality. Results show that skin ground color becomes uncorrelated with flesh color for skin ground color hue angles below 70°. Cultivar-specific models using nondestructive, log-transformed, interactance measurements at two wavebands in the visible region produced good predictive performance of flesh hue (r=0.92), while a global model required information at five wavebands to achieve this same level of performance (r=0.92 and RMSECV=1.35° hue). The nondestructive method does not require a separate measurement of skin reflectance and is suitable for flesh color grading tasks at inspection stations prior to canning and shows good potential for on-line sorting tasks.