Sint-Katelijne-Waver, Belgium
Sint-Katelijne-Waver, Belgium

Time filter

Source Type

Jacobs B.A.J.G.,42 Technology | Verlinden B.E.,42 Technology | Bobelyn E.,42 Technology | Decombel A.,Inagro vzw | And 6 more authors.
Postharvest Biology and Technology | Year: 2016

Lamb's lettuce (Valerianella locusta L.) can be stored up to 28 days without being indistinguishable from fresh material by the human eye. However, due to the prior storage period the shelf life potential is limited and this leads to losses in distribution and a lower quality for the consumer. This work aims to develop a rapid and non-destructive methodology using visible/near infrared (Vis/NIR) reflectance spectroscopy to detect and quantify a prior storage period. Vis/NIR reflectance spectra were linked to the time in storage by partial least squares regression (PLS). Different variable selection techniques (interval PLS, Variable Importance in Projection scores, Genetic Algorithms PLS and Monte Carlo Uninformative Variable Elimination PLS) were combined to improve the accuracy and robustness of the prediction model, while decreasing the number of used wavelengths. The final model used only 10% of the original wavelengths, while the root mean squared error of cross validation decreased from 6.0 to 3.6 days. The final model was tested using 2 external test sets and had a maximum root mean square error of prediction of 3.7 days. Vis/NIR reflectance spectroscopy can be a valuable, rapid and non-destructive method for identifying and quantifying a prior storage period of lamb's lettuce. © 2015 Elsevier B.V.


Jacobs B.A.J.G.,42 Technology | Verlinden B.E.,42 Technology | Bobelyn E.,42 Technology | Decombel A.,Inagro VZW | And 5 more authors.
Acta Horticulturae | Year: 2015

Lamb's lettuce (Valerianella locusta L.) delivered to the vegetable auctions is not always fresh. The product can be stored for a certain time depending on the time of year. Stored and freshly harvested material is visually not distinguishable, but the shelf life potential of the first is limited. This leads to losses in distribution and a lower quality for consumers. The aim of this work was to develop a fast nondestructive methodology that uses visible/near infrared (Vis/NIR) reflectance spectroscopy that can determine whether lamb's lettuce has been in storage and give an idea about the remaining shelf life potential. The Vis/NIR reflectance spectra were linked to the time in storage and to the quality of the samples at the end of a shelf life holding period by partial least squares regression (PLS). The prediction of the remaining shelf life potential was not successful based on colorimetric quality attributes. There was a better performance when the quality scores given by a panel of experts was used, but for the moment this prediction model lacks accuracy. The detection and quantification of a prior storage period was validated with an external test set and the root mean square error of prediction (RMSEP) was 2.5 days. Vis/NIR reflectance spectroscopy was a valid, fast and non-destructive method for determining and quantifying a storage period of lamb's lettuce.

Loading Proefstation voor de Groenteteelt VZW collaborators
Loading Proefstation voor de Groenteteelt VZW collaborators