18C-1 |
|
E. J. BIRCH, Dept. of Food Science, Univ . of Otago, PO Box 56, Dunedin, 9015, New Zealand and S. M. Hall. The Chilean guava berry (Myrtus ugni) is being rediscovered in New Zealand as a potential export crop. The international market is currently supplied only by Chile and potentially Australia. The fruit are 1 – 1.5 cm and freely borne on bushes up to 2 m. The edible fruit was popular during the 1800s in England but is little reported recently despite the intense flavor, described as a combination of apples, strawberries and pineapple. Also the leaves can be used as a tea substitute and the roasted seeds as a coffee substitute. The objective of this study was to investigate the proximate and volatile composition of the berry to compare with other fruit and berries. Proximate analysis was performed on ripe berries for water, fat, protein, ash, minerals, fiber and energy using AOAC methods. Total carbohydrate was obtained by difference. The berries were analyzed for free sugars and vitamin C by HPLC. Fatty acid composition was obtained by GC analysis of FAMES. Solid-phase-micro-extraction (SPME) followed by GC-MS was employed for volatile analysis on the intact berries. Mature berries were low in vitamin C, fat, protein and ash (all less than 1% fresh weight) but higher in free sugars, fiber, and energy than comparable fruit and berries. Fatty acid composition most resembled blackberry, being similar to pineapple and strawberry, but more unsaturated than apple, cranberry or guava. The berries had a number of volatiles characteristic of the fruit they have been likened to. The major volatiles comprised fragrant fatty acid esters along with terpenes, aldehydes, furanones and alcohols. The Chilean guava berry is likely to be marketed as a cranberry in New Zealand although its aromatic character is unlike that of any single fruit or berry but reminiscent of many. The distinctive aroma profile will provide an attractive food flavoring alternative.
Session 18C, Food Chemistry: Food composition, analysis and volatiles
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |