Assessment of sensory profile and instrumental analyzed attributes influenced by different potassium fertilization levels in three tomato cultivars

Abstract

Sensory properties are an essential quality aspect when the consumption of fresh tomato is under consideration. The flavor of tomato is defined as a combination of taste sensations (sweetness, sourness), aroma (volatile compounds), and texture (firmness, mealiness), some of which are proven to be affected by insufficient nutrient supply − especially potassium (K). This study intends to undertake a holistic assessment of the K fertilization effect on the flavor of tomato by connecting the use of sensorial and instrumental methods. An optimal K supply significantly increased the sensory descriptors sweetness, sourness, and aroma as well as the instrumental estimated color, firmness, total soluble solids (TSS), titratable acids (TA), and dry matter (DM) in a cultivar-specific manner. The volatile organic compounds (VOCs) were not significantly affected by K fertilization. The evaluation by the panelists confirmed the results of the instru-mental analyses, by which an increment in the fruit quality with rising K supply could be detected. An optimal K supply of 3.66 g/plant could be suggested to increase tomato flavor in the cocktail cultivars studied: Primavera and Yellow Submarine. Cultivar effects should, therefore, be considered for defining the optimal K fertilizer dose that favors high tomato fruit quality and, hence, better flavor.