May 10, 2010 - J. Agric. Food Chem. 2010, 58, 6697â6705 6697. DOI:10.1021/ .... of 1%. The second was adjusted to pH 9 using 30% ammonium .... A matrix of features as defined by retention ..... els (43). It is thought, however, that a mixture of compounds .... Young, M. R.; Colburn, N. H.; Albert, P. S.; Bennink, M. R.;.