Author
EVANS, D - UNIVERSITY OF ADELAIDE | |
RATCLIFFE, M - VICTORIA INST/DRYLND AGRI | |
Jones, Berne | |
BARR, A - UNIVERSITY OF ADELAIDE |
Submitted to: Australian Barley Technical Symposium Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 8/15/1999 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Beer foam stability is one of the main parameters that is critical to a consumer's assessment of beer quality. The quantities of the malt proteins Z4 and LTP1 have been found to influence foam quality. ELISAs developed to the proteins Z4, Z7 and LTP1 were used to measure the quantities of these proteins in malts made from barley grown in 1996 (seven varieties, five sites) and 1997 (commercial malts and micromalts from five Australian barley breeding programs). The varieties Alexis, Arapiles, Chariot, Franklin, Gairdner, Grimmett, Harrington, Lindwall, Picola, Sloop, Tallon and Unicorn have high levels of protein Z4 (means 1050-1350ug/g) while Chebec, Fitzgerald, Manley, Parwan, Schooner and Stirling have intermediate levels of protein Z4 (means 570-870ug/g). The level of LTP1 was somewhat lower in all varieties grown in the 1997 season (300-500ug/g) compared to the 1996 season (500-800ug/g). Two exceptions were those grown in WA and Sloop which had LTP1 contents more typical of the 1996 growing season. We do not know why the 1997 LTP1 levels were low. Polymorphisms for the level of protein Z4 and Z7 were also measured by ELISA in the experimental Chebec (intermediate Z4/Z7) x Harrington (high Z4/Z7) and Harrington x Morex (low Z4, high Z7) populations. Interval mapping showed that protein Z4 mapped with a single association located on chromosome 4B with highly significant LOD scores of 19.2 and 32.3 in the Chebec x Harrington and Harrington x Morex populations, respectively. Interval mapping of protein Z7 content in the Harrington x Morex population showed a single association located on chromosome 7B with a highly significant LOD score of 13.4. |