Vis/NIR reflectance spectroscopy can predict shelf life potential of lamb?s lettuce

Lamb?s lettuce (Valerianella locusta L.) delivered at the vegetable auctions is not always fresh. The product could be stored for a certain period depending on the season. The stored samples cannot be distinguished visually from fresh material but their shelf life potential is reduced compared to that of the latter. Batches with limited shelf life potential lead to losses in distribution and lower consumption quality. The aim of this work was to develop a fast non-destructive methodology using visible/near infrared (Vis/NIR) reflectance spectroscopy that can determine the time that lamb?s lettuce has been in storage and predict its shelf life potential. Lamb?s lettuce samples, grown in an experimental garden and by commercial growers, were stored at 1 and 4?C with a relative humidity greater than 90%. Vis/NIR spectra of the samples were measured at harvest and 3 times during a storage period of 21 d. At the same time, the quality was assessed by a panel of experts and samples of each batch of Lamb?s lettuce were taken for determining physiological parameters. After each storage period, samples were subjected to a shelf life holding period of 10 d at 8?C. The quality was determined by the same panel of experts and colorimetric measurements were performed. Physiological analyzes showed a gradual decrease of chlorophyll a, chlorophyll b, glucose, fructose and sucrose during storage. The respiration rates during storage declined during the first 2 weeks and remained stable afterwards. Vis/NIR reflectance spectra were linked to the time in storage and shelf life quality using partial least squares regression (PLS). The resulting PLS-model was able to determine the stored period of an external test set of lamb?s lettuce with a root mean square error of prediction of 2.56 d. ? Original title, complete list of authors and sourcesPredicting stored period and shelf life potential of lamb?s lettuce using Vis/NIR reflectance spectroscopyB.A.J.G. Jacobs, B.E. Verlinden, A., Decombel, P. Bleyaert, J. Van Lommel, I. Vandevelde, W. Saeys, B.M. NicolaiVCBT, Flanders Centre of Postharvest Technology, Willem de Croylaan 42, 3001 Leuven, Belgium V Postharvest Unlimited, ISHS International Conference, 10-13 June 2014, Cyprus, The picture is by marksdailyapple.com Key wordsPoscosecha?? ?postcosecha?? ?postharvest?? ?na-oes?? ??? ??? ???????? ????? ??? ?post-r?colte?? ????? ?? ??????????? ??? ?na-oogst?? ?post-raccolta?? ?Obr?bka po?? ?p?s-colheita?? ????????????????? ?hasat sonras??? ??? ?Ernte?? ????????????????? ????? ????????????? ?postcollita?? ?poskliz?ov頠 ????? ??? ??? ??? ?nakon branja?? ?pozberov頠 ??? ?obdelovanje zemlje po?? ?post-colleita?? ?????? ??????? ?pascapanen?? ??il?onn postharvest?? ??????? ?p?c ra?as?? ?derliaus apdirbimas po?? ?lepas tuai?? ??? ?? ???????? ?post-recoltare?? ??????? ??????? ???????????????????? ?????????????? ?????????????????? ?sau thu ho?ch?? ?????????????????? ?zangemva kwenkathi yokuvunaCan?nigo, hierba de los ?? ?Valerianella?? ?Lamb?s lettuce?? ?Lam se blaarslaai?? ????? ????? ??? ???????? ??afido de laktuko?? ?m?che?? ?????????????? ????? ?????? ?veldsla?? ??? ?roszponka?? ?alface-de-cordeiro?? ?????? ????????? ?kuzu marul?? ?????? ?? ?????? ?Feldsalat?? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ??? ????