Single-cultivar cloudy juice made from table apples: an attempt to identify the driving force for sensory preference

Abstract

Five single-cultivar cloudy juices made from table apples and an industrially manufactured cloudy apple juice were subjected to chemical and physical analysis, and flash profiling and preference testing by untrained panelists. The fruit juices mainly varied with respect to total dry matter, soluble extract and acid content, giving a sugar/acid ratio (fructose, glucose plus sucrose related to malic acid equivalents) between 15.8 and 27.7; cluster analysis was used to calculate similarity values. There was also a large difference in cloud particle size and stability, with diameters (d 90) ranging between 3.9 μm (industrially produced juice) and 160 μm (single-cultivar juice from Elstar apples). Flash profiling performed in two repeated sessions by 19 untrained panelists elicited 31 descriptors (appearance: 17; smell, flavour and taste: 14). The most frequently used descriptors were cloudiness and colour, and sweetness and acidity. Hedonic ranking by 110 untrained panelists revealed that the less sweet and more acidic products were significantly preferred; however, there was a subfraction of approximately one-third of the panel who preferred the samples with a higher sugar/acid ratio. The comparison of principal component analysis of analytical data and generalised procrustes analysis of flash profiling data reveals that the main driving source for sensory preference is the sugar/acid ratio in line with turbidity and colour intensity.