Articles
STUDIES ON THE INTRINSIC QUALITY OF CARROT, TOMATOES AND LETTUCE DURING MARKETING
In the present study, some methods suitable for the characterization of intrinsic quality were investigated in regard to practicability.
These methods were then used to evaluate the quality properties of three vegetables on the market.
In addition, the external properties determining the quality grade, such as size and defects, were also taken into account.
At present it is far from clear which methods were most suitable for the characterization of intrinsic quality.
Accordingly, one aim of this study was to develop and standardize the sensory methods needed and coordinate these methods with the evaluation of quality grade.
Another aim was to investigate some simple analytical methods, to determine whether they were practicable for the characterization of the intrinsic quality and whether correlations existed between the sensory properties and the analytical results.
It was assumed that if suitable methods were found, they would be applicable as quality criteria in the product development of fresh market vegetables.
Similarly, such methods might be useful in quality control at various stages of the marketing chain.
Three market vegetables were studied: 1) lettuce, with a short shelf-life, 2) tomato, with a medium shelf-life, and 3) carrot, with a long shelf-life.
The vegetables were obtained immediately after delivery to 5 wholesale dealers.
The material consisted of samples in June, August and September.
Quality was evaluated by sensory means, the properties studied being appearance, consistency, smell and taste.
In addition, the external quality grade was evaluated.
Analytical criteria were soluble solids (all the vegetables), acid content (tomato), ascorbic acid (tomato and lettuce), and nitrate content (lettuce and carrot). The possible existence of correlations between the criteria were studied.
In general, the criteria of quality studied appeared to be independent, and therefore adequate characterization of quality requires the use of all the methods.
For instance, bitter taste in carrots or level of nitrate could be determined only by the appropriate method.