SENSORY AND INSTRUMENTAL ANALYSIS OF THE JUICINESS OF STRAWBERRIES

ABSTRACT Juiciness is an important quality characteristic of strawberries. However, at present there is no easy instrumental method to analyze the juiciness, that is independent of the operator. Furthermore, the correlation of the existing methods with sensorial analyses is not always completely established. In this study, a new instrumental method is developed and compared with existing instrumental methods and with sensory evaluation by a trained sensory panel. Fifteen types of strawberries (different varieties and ripeness) are used for the evaluation. The best instrumental method starts with freezing the strawberries. After chopping the frozen strawberries in a blixer, the strawberry pieces are thawed in a known volume of water. The total amount of liquid, filtrated through a Buchner funnel, is weighed and the instrumental juiciness is calculated from the weight difference. This method has the lowest variation coefficient and the best correlation with the juiciness determined by the sensory panel. PRACTICAL APPLICATIONS Juiciness is an important parameter for most fruit types and it certainly is for strawberries. A reliable, instrumental method to determine the juiciness is therefore highly wanted by all stakeholders (growers, traders, industry). The instrumental method developed in this research shows a good correlation with sensory analyses and a high reproducibility. In addition, the method requires only standard lab equipment. This method can, therefore, be easily implemented in all labs, which allows a widespread application.

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