Shelf life and waste in the value chain of vegetables // Shelf-life and waste in the value chain of vegetables




Jóhanna Elín Ólafsdóttir; Guðný Sif Sverrisdóttir; Kolbrún Sveinsdóttir; Aðalheiður Ólafsdóttir; Guðjón Þorkelsson; Ólafur Reykdal

Supported by:

Matvælasjóður / Icelandic Food Innovation Fund


Ólafur Reykdal

Project Manager

In the project, the shelf life of vegetables was examined. Sensory evaluation of tomatoes, potatoes, carrots and beets was carried out for 6 weeks in the summer of 2021. The vegetables were stored under three different storage conditions: (1) Cooler 1 which was at 2 ° C, (2) cooler 2 at 12 ° C and (3) a room that was at about 22 ° C. Sensory evaluation was performed on carrots and beets from a room at 2 ° C and a sensory evaluation of tomatoes and potatoes from a room at 12 ° C. In addition, a quality inspection was carried out on the four vegetable species from all three compartments. Humidity and temperature were monitored in each room, vegetables were weighed to monitor shrinkage and samples were taken for bacterial measurements. 

Quality factor (QIM) method was used for sensory evaluation. Sensory evaluation scales were improved throughout the project. Sensory evaluation results using these scales showed that they can be useful in assessing the freshness of the vegetables studied. Bacterial measurements were performed on tomatoes and paper packaging of tomatoes. The results of those measurements showed that microorganisms grow well on paper packaging. 

Beets and carrots lost a considerable amount of weight, but it must be borne in mind that the humidity in the refrigerated rooms was not as good as it could be. Quality assessed by sensory evaluation became poorer with time for all the vegetable species. The quality deteriorated relatively most for tomatoes but least for carrots. This is due to the different shelf life of the species. In the sixth week of the study, all vegetables except carrots were considered unfit for consumption. 

The work was part of the project Improved quality, shelf life and less waste in the value chain of Icelandic vegetables but it is funded by the Food Fund. Jóhanna Elín Ólafsdóttir and Guðný Sif Sverrisdóttir were summer employees at Matís for the project. The work yielded important results in the development of sensory evaluation scales and the results will be utilized in shelf life research on vegetables in the future.

The Quality Index Method (QIM) was used for sensory evaluation. Scales were developed for tomatoes, potatoes, carrots and rutabagas. The method was found useful for sensory evaluation of the freshness of vegetables, but the scales need further development. The quality of the vegetables as measured by the QIM method decreased throughout the experiment. The weight of rutabaga and carrots decreased considerably throughout the experiment. 

This work was a part of the project Improved quality, shelf-life and reduced waste in the value chain of Icelandic vegetables. The work was important for the development of suitable QIM scales for sensory evaluation of vegetables. Future shelf-life experiments will benefit from this work. 

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