SENSORY, CHEMICAL AND GAS-CHROMATOGRAPHIC EVALUATION OF 5 RASPBERRY CULTIVARS

Five raspberry cultivars, 'Chilcotin', 'Chilliwack', 'Meeker', 'Skeena' and 'Tulameen', were evaluated for sensory attributes, and chemical and flavor volatile compounds. 'Chilliwack' and 'Tulameen' received high ratings in sweetness and overall impression with high soluble solids, total sugars and sugar:acid ratio. 'Chilcotin' rated low in overall impression and sweetness, and high in sourness and astringency, with low soluble solids, sugar:acid ratio and total sugars, and high titratable acidity. Principal factor analysis (PFA) of the sensory results separated the cultivars based on desirable (appearance, color, texture, aroma and sweetness) and less desirable (sourness, bitterness, astringency and off-flavor) attributes. Twenty-eight volatile compounds were analyzed by dynamic headspace and 18 identified by gas chromatography-mass spectrometry (GC-MS), most of which were terpenes which included alpha-pinene, sabinene, gamma-terpinene, alpha- and beta-ionone and caryophyllene. Volatile compounds varied among cultivars, with benzaldehyde (11-1-31-8%), a-pinene (4.0-11.5%), ethyl heptanoate (6.9-15.2%), beta-myrcene (13.2-19.6%) and gamma-terpinene (12.2-20.0%) as the predominant volatiles. Correlation analysis established no relationships between sensory and chemical data with volatile compounds.