Grapefruit juice volatiles were collected and analyzed by gas-liquid chromatography for 24 samples of commercial single-strength grapefruit juice from different production days and storage conditions. With the help of multivariate statistics, attempts have been made to classify them according to the chromatographic data and sensory evaluation of the juice. The data was analyzed by canonical and cluster analysis. As a typical result, it was found that using three constituents, the samples could be class$ed into four different quality classes. From the point of view of sensory interpretation, the canonical analysis also proved to be an interesting approach. Of the three more signijicant constituents, nootkatone and an unknown constituent have positive contribution, while another unknown constituent give a reverse contribution.

The relationship between physicallchemical properties and sensory properties of commercial canned single-strength grapefruitjuice was investigated by using principal component analysis. Processing of the data resulted in the formation of two distinct groups. When the characteristics that contribute to the principal components were examined, it was concluded that acid, total soluble soliddacid and total soluble soliddacid -naringin ratios had a pronounced effect on classification. Consequently, the samples were classiped into two quality groups considered as commercial grade A and grade B. Theflrst had the higher sensory values.