The potential of NIRs as a non-destructive post-harvest quality assessment tool for ‘Triumph’ persimmon fruit

The potential of near-infrared spectroscopy (NIRs) as an alternative non-destructive post-harvest quality assessment tool for ‘Triumph’ persimmon fruit was assessed. Fruits were harvested at four stages of maturity and each stage was replicated four times. Fruit quality was assessed at harvest, after storage and after shelf-life. Spectra data were obtained by scanning three positions on each fruit: green equatorial, yellow equatorial and the stylar end using a multi-purpose analyzer (MPA) spectrometer. Reference data for flesh firmness, total soluble solids (TSS), titratable acidity (TA) and fruit colour were determined using conventional tools on the same fruits from which NIR spectra were obtained. Reference data confirmed that a colour chart cannot categorize fruits into precise distinctive quality classes at harvest. In both the 2012 and 2013 seasons, all measured parameters had overlapping quality ranges across maturity stages. NIRs calibration and validation models showed that NIRs can predict TSS and fruit colour throughout post-harvest storage of ‘Triumph’ persimmon fruit. Furthermore, NIRs has shown some potential to predict firmness and TA by scanning certain fruit positions after storage and after shelf-life. NIRs can therefore be an alternative to the destructive TSS and TA quality assessment tools.