Title : Sensory characteristics of three different open pollinated beetroot cultivars Beta vulgaris L ssp vulgaris conditiva compared to two F1 hybrids
About a quarter of the beetroot, Beta vulgaris subsp. vulgaris (conditiva), produced in Germany grows on organic land, which makes this vegetable a typical organic product. Beetroot contains considerable concentrations of biologically active substances, which are relevant to its taste. However, the relevant compounds are not characterized in many beetroot cultivars, especially in those used in the organic sector. The overall aim of the project is to characterize taste relevant compounds in different cultivars. Based on these results new open pollinating red beet cultivars will be bred using the traditional method of single plant selection, which is in line with the concept of organic agriculture, in order to use the cultivars potential to improve taste and health-promoting substances. Juice samples were produced from three different open-pollinated cultivars, namely, Robushka, Nochowski, Jannis and two F1 hybrids, Boro and Monty. The beetroots were grown under organic conditions, at the research station of the University of Hohenheim (Stuttgart, Baden-Württemberg, Germany). The sensory evaluation was set up using 37 untrained panelists, which were among the master students and staffs of the University of Hohenheim. The organoleptic attributes evaluated were: sweetness, aroma intensity, bitterness, earthy taste and overall acceptability. The order of presentation of samples to the participants was randomized for each panelist. The juice samples were served in clear glasses to the participants and in order to avoid carryover taste, plain bread was available and water was provided to rinse the mouth between evaluations. Each sensory attribute was scored on a 10 – point Hedonic Scale. The data were analysed using a mixed model approach fitting fixed effects for cultivar and random effects for order and panelists. The results indicated significant differences in sweetness and earthy taste between the cultivars (p< 0.0001 and p= 0.0022, respectively). Nochowski was evaluated as a cultivar with the sweetest and lowest bitterness taste compared to all other studied cultivars. However, Robuschka was rated as a cultivar with the highest aroma intensity, lowest earthy taste and highest overall-acceptability. Taking all the cultivars into account, the open-pollinated cultivars showed more sweetness, less bitterness and higher overall-acceptability compared to F1 hybrid cultivars.