The effect of pH on the formation of volatile compounds produced by heating a model system containing 5’-Imp and cysteine

Abstract

A identificação de compostos voláteis formados a partir de reações entre Inosina-5'-Monofosfato (5'-IMP) e cisteína a três diferentes pH (3,0; 4,5; 6,0) e 140 °C foi realizada através da análise de ''headspace'' dinâmico. Os resultados mostraram que mais de 90 compostos voláteis foram produzidos, principalmente compostos heterocíclicos, incluindo furanos sulfurados, tiofenos, tiazoles, furanos, sulfitos alquilados, compostos bicíclicos e sulfitos cíclicos. Os estudos demonstraram que os furanos sulfurados, mercaptocetonas e alquil-furanos foram formados principalmente a pH ácido, enquanto que as pirazinas foram completamente inibidas a pH elevado. Estes resultados confirmam observações preliminares de que o pH exerce uma grande influência nos compostos voláteis formados em reações de Maillard.The identification of volatile compounds formed from the reactions of Inosine-5'-Monophosphate (5'-IMP) with Cysteine at three different pH (3.0; 4.5; 6.0) and 140 °C were performed using dynamic headspace analysis. The results gave over 90 volatile compounds, mainly heterocyclic compounds, including sulphur containing furans, thiophenes, thiazoles, furans, alkyl sulphides, bicyclic compounds and cyclic sulphides. The studies showed that sulphur-substituted furans, mercaptoketones and alkylfurans were formed mainly at acidic pH, while pyrazines were completely inhibited at high pH. These findings support an earleir observation that pH has a great influence on volatile compounds formed in Maillard type reactions.

Influence of extracted 5-nucleotides on aroma compounds and flavour acceptability of real beef soup

“…Mercaptoketones that produce important meat-like volatiles can be prepared by the reaction of dicarbonyls, 2, 3-butandione (3) and 2, 3-pentandione (9) (sugar degradation products) with hydrogen sulfide (Strecker degradation products of cysteine). [35] Acetyl thiazole (33) and benzo thiazole (47) were found in the aroma of the control sample (Table 2). These compounds were reported amongst the dominant sulphur-containing compounds in cooked beef meat.…”

“…They are degradation products of sugar and considered as important intermediate in the formation of the two mercaptoketone compounds 14 and 21 by the interaction with hydrogen sulfide. [35] These diketones were reported amongst the meat odour active compounds and described to have a buttery note. [1] As shown in Fig.…”

Determination of some water-soluble aroma precursors in goat meat and their enrolment on flavour profile of goat meat

“…The overall effect of cooking was greatest on cysteine, which exhibited a decrease of 70% in concentration, while methionine was reduced by 29%. The sulphur-containing amino acids are of particular interest for aroma formation, since they act as precursors of volatile sulphur-containing compounds formed during cooking (Madruga & Mottram, 1998). A high reduction in cysteine during cooking has been reported in meat and model systems (Mottram, 1998).…”

“…For example, addition of cysteine to raw muscle favoured the formation of aroma-potent thiophenes in a cooked meat system (Madruga & Mottram, 1998). Other amino compounds, such as creatine, carnosine, creatinine and nucleotides, have also been implicated in the formation of meat flavour (Macy et al, 1964b).…”

Comprehensive two-dimensional gas chromatography (GC × GC) measurements of volatile organic compounds in the atmosphere

“…2a), but there are some differences between both chromatograms. On the TIC chromatogram there seems to (2001); (2) Hayes and Pitzer (1985); (3) prediction using the method of Zenkevich (1998); (4) HaagenSmit Laboratory (1997); (5) Laub and Purmell (1988); (6) Lubeck and Sutton (1984); (7) Helmig et al (1996); (8) Bermejo et al (1987); (9) Andrade et al (2000); (10) (2000); (15) Madruga and Mottram (1998); (16) Weber (1986) be a band 0.4 s above the lowermost band (i.e. the alkane band).…”