Table 4.

Strecker aldehydes detected by GC-O in cooked beef extractions ^a, amino acid precursor, and odour threshold ^b.

Strecker aldehyde	Structure	Amino acid precursor	Odour threshold
ethanal = acetaldehyde		α-alanine/cysteine	25
propanal		α-aminobutyric	-
2-methylpropanal		valine	2
3-methylbutanal		leucine	3
2-methylbutanal		isoleucine	4
methional		methionine	0.2
2-phenyletanal = phenylacetaldehyde		phenylalanine	4

^a [31,59,61,62]; ^b In µg/L, determined in water [15].