Key Odorants in Japanese Roasted Barley Tea (Mugi-Cha)—Differences between Roasted Barley Tea Prepared from Naked Barley and Roasted Barley Tea Prepared from Hulled Barley

Abstract

The volatiles isolated by solvent extraction and solvent-assisted flavor evaporation (SAFE) from roasted barley tea, prepared from either hulled barley or naked barley, were subjected to a comparative aroma extract dilution analysis, which resulted in 27 odor-active compounds with flavor dilution factors (FD factors) of 64–1024. An additional 5 odorants were detected by static headspace analysis. Quantitation of these 32 compounds revealed 22 and 23 odorants in the naked barley tea and in the hulled barley tea, respectively, that exceeded their odor-threshold values. On the basis of these data, the aromas of both barley tea variants were successfully reconstituted with reference compounds. The calculation of odor-activity values (OAVs = concentration/odor-threshold value) and omission tests suggested 2-methoxyphenol (OAVs 69 and 160) and trans-isoeugenol (OAVs 1.4 and 31) as key compounds responsible for the stronger smoky note in the hulled barley tea. Further important odorants in the naked and hulled barley teas included 2-acetylpyrazine (OAVs 23 and 16), 2-acetyl-1-pyrroline (OAVs 19 and 16), and 3-methylbutanal (OAVs 12 and 15).

Odour-active compounds in liquid malt extracts for the baking industry

“…The ethereal extracts obtained from the different materials were dried over anhydrous sodium sulphate and non-volatiles were removed by SAFE at 40 °C. The SAFE distillates were separated into neutral and basic volatiles (NBV) and acidic volatiles (AV) as detailed in [39]. Fractions NBV and AV were concentrated to final volumes between 0.2 mL and 5 mL.…”

Impact of Malt Extract Addition on Odorants in Wheat Bread Crust and Crumb

“…The structure proposals were then confirmed by parallel GC–O analyses of the bread volatile isolates and authentic reference compounds using two columns of different polarity (DB-FFAP and DB-5) and finally by parallel GC–MS analyses using a GC×GC–TOFMS system. To reduce coelution problems, the bread volatile isolates were fractionated by acid–base extraction before GC×GC–TOFMS analysis …”

“…The combined organic phases were dried over anhydrous sodium sulfate, and non-volatiles were removed by SAFE at 40 °C . To reduce background during GC–mass spectrometry (MS) analysis, the SAFE distillate was fractionated into neutral and basic volatiles (NBV) and acidic volatiles (AV) using aqueous sodium carbonate and the procedure detailed by Tatsu et al . Fractions NBV and AV were concentrated to final volumes of 0.2–5 mL, and the concentrates were subjected to GC–MS.…”

Characterization and Quantitative Comparison of Key Aroma Volatiles in Fresh and 1-Year-Stored Keemun Black Tea Infusions: Insights to Aroma Transformation during Storage

“…The fractionation of acidic and neutral-basic tea volatiles followed a procedure described in a previous paper [ 7 ]. KBT volatiles were isolated and extracted as described in the previous section.…”