Aroma active alkylated pyrazines are produced by Basfia succiniciproducens as by‐products of succinic acid production

Abstract

Culture supernatants of Basfia succiniciproducens derived from the industrial production of succinic acid exhibit an intense nutty, root vegetable‐like, buttery and sourish smell. By means of headspace‐gas chromatography‐mass spectrometry‐olfactometry (HS‐GC‐MS‐O), 14 odour‐active compounds were perceived and identified using two GC‐columns of different polarity and comparison of retention indices and mass spectra to those of authentic reference compounds. Several alkylated pyrazines, including 2,3,5‐trimethylpyrazine, 5‐ethyl‐2,3‐dimethylpyrazine, 2,3,5,6‐tetramethylpyrazine, 2,3,5‐trimethyl‐6‐ethylpyrazine, 2,3,5‐trimethyl‐6‐propylpyrazine and 2,3,5‐trimethyl‐6‐butylpyrazine were found to contribute to the aroma of the culture supernatant. Quantitation of the pyrazines was performed by means of dynamic headspace‐GC‐MS after standard addition, and 2,3,5,6‐tetramethylpyrazine (9.10 mg/L) was the most abundant compound. Waste streams of the biotechnological production of commodity chemicals may thus represent a sustainable resource for the isolation of aroma compounds.

Comparative evaluation of commercial Douchi by different molds: biogenic amines, non-volatile and volatile compounds

“…Due to the different environments associated with molds, different bacterial communities were present in the three types of Douchi, leading to differences in organic acid distribution. Aspergillus-type Douchi contained more acetic acid, making it sourer, simultaneously, the presence of succinic acid provides an umami taste for Rhizopus-type Douchi [33].…”

“…Mucor-type Douchi contains more esters and alcohols, endowing it with aromatic and fruity flavors. 2,3,5-trimethyl pyrazine and tetramethyl pyrazine were present in Rhizopus-type Douchi and were considered to be the main sources of soy sauce and Douchi aroma [33]. Conversely, the excessive fermentation of Aspergillus-type Douchi increased the levels of acetic acid and aldehydes, which are associated with beany and unpleasant flavors [39], leading to flavor deficiencies.…”