Details

Autor(en) / Beteiligte

• Dach, Anna
• Schieberle, Peter

Titel

Changes in the Concentrations of Key Aroma Compounds in Oat (Avena sativa) Flour during Manufacturing of Oat Pastry

Ist Teil von

• Journal of agricultural and food chemistry, 2021-02, Vol.69 (5), p.1589-1597

Ort / Verlag

United States: American Chemical Society

Erscheinungsjahr

2021

Quelle

MEDLINE

Beschreibungen/Notizen

• Application of the aroma extract dilution analysis on the volatiles isolated from oat flour revealed 30 aroma-active compounds in the flavor dilution (FD) factor range of 2–8192, among which oat-flour-like smelling (E,E,Z)-2,4,6-nonatrienal showed by far the highest FD factor. Quantitation performed by stable isotope dilution assays and a calculation of odor activity values (OAV; ratio of the concentration to odor threshold) of 23 odorants showed an OAV of above 1. Among them, vanillin, (E,E,Z)-2,4,6-nonatrienal, 2-acetyl-1-pyrroline, 3-methylbutanoic acid, and 2-methoxy-4-vinylphenol showed the highest OAVs. In a heated (70 °C for 30 min) oat dough prepared by kneading the oat flour in the presence of sucrose and water, 34 aroma-active compounds were identified, among which 17 compounds appeared with an OAV of ≥1. During frying, the weak cereal-like aroma of the oat flour and the oat dough was changed with the generation of an intense roasty, popcorn-like aroma attribute. A comparison to recently published data on oat pastry prepared by toasting of the same dough showed a clear increase in the overall aroma intensity from flour to pastry, in particular, in the popcorn-like, roasty odor impression. Especially considerable increases in the concentrations of the popcorn-like smelling compounds 2-acetyl-1-pyrroline, 2-acetyl-3,4,5,6- and 2-acetyl-1,4,5,6-tetrahydropyridine, 2-propionyl-1-pyrroline, and 2-acetyl-2-thiazoline were measured. In addition, the concentrations of the Strecker aldehydes 2- and 3-methylbutanal, phenylacetaldehyde, and 3-(methyldithio)­propanal were also much increased during the toasting process. In contrast, in line with the overall aroma profile, particularly the concentration of the oat-like smelling compound (E,E,Z)-2,4,6-nonatrienal was decreased during processing. The formation and precursors of the key aroma compounds are discussed.