No abstract

The chemical composition, colour and texture of fresh berries from three rabbiteye ('Climax', 'Premier' and 'Tifblue') and two highbush ('Bluecrop' and 'Jersey') blueberry cultivars were measured. Shear (482 vs 290 N), compression (6.50 vs 3.96 N) and puncture forces (1.48 and 0.85 vs 0.81 and 0.43 N) were higher (P ≤ 0.05) for rabbiteye than for highbush cultivars. Shear for 'Bluecrop' blueberries averaged 254 N, whereas for 'Climax' it was 565 N. The puncture force required to penetrate the skin was lower for 'Bluecrop' (0.78 N) and 'Jersey' (0.83 N) and higher for 'Climax' (1. 71 N). However, sensory panellists found no differences (P > 0.05) in colour, flavour or skin toughness among the five cultivars. 'Climax' was rated lower in seediness. Rabbiteye cultivars contained more fibre and complex polysaccharides than highbush cultivars. These differences in complex carbohydrates that make up the cell wall layers may contribute to the toughness of rabbiteye cultivars and their possible longer fresh shelf-life, though taste panellists did not find this toughness objectionable.

No abstract

The volatiles of longon (Lansium domesticum Corr. var Dongon), mangosteen (Garcinia mangostana L. var Native), durian (Durio zibethinus L. var Monthong), rambutan (Nephelium lappaceum L. var Rong-rien), and sapodilla (Manilkara zapota van Royer var Kai) were identified by headspace-solid phase microextraction with the gas chromatography-mass spectrometry technique. The headspace volatiles of fresh, unheated, salted out with NaCl, and NaCl + heated samples were determined. Salting out gave the highest number of volatile components with the longon headspace. High temperature did not have much affect on the amount of volatiles in the headspace. Major volatiles of the total 43 volatiles in longon were 1,3,5 trioxane, (E)-2-hexenal, 3-carene, α-cubebene, isoledene, δ-selinene, and α-calacorene. Major volatiles of mangosteen were 2, 2-dimethyl-4-octanal, E-2-hexenal, benzaldehyde, (Z)-3-hexen-1-ol, hexyl–n-valerate, 1,4-pentadiene, and 2-methyl-1, 3-buten-2-ol. Volatile compounds in durian consisted of a large number of sulfur-containing compounds, which included diethyltrisulfide, diethyldisulfide, dithiolane, dimetyl sulfide, and 3-methyl-thiozolidine. Nonsulfur compounds 2-methyl butanoate, butanedioic acid, and propyl-2-ethylbutanoate were also abundant. Isocitonellol, 3-hydroxy-2-butanone, pentanal, and 4-tridecyl valerate were most abundant in ‘Rong-rien’ rambutan. A total of 23 components were characterized in sapodilla with ethyl acetate, acetaldehyde, benzyl alcohol, and 2-butenyl benzene being the major volatiles.

No abstract