Formation of Pyrazines in Maillard Model Systems: Effects of Structures of Lysine-Containing Dipeptides/Tripeptides

Abstract

At present, most investigations involving the Maillard reaction models have focused on free amino acids (FAAs), whereas the effects of peptides on volatile products are poorly understood. In our study, the formation mechanism of pyrazines, which were detected as characteristic volatiles in sunflower seed oil, from the reaction system of glucose and lysine-containing dipeptides and tripeptides was studied. The effect of the amino acid sequences of the dipeptides and tripeptides on pyrazine formation was further highlighted. Four different dipeptides and six tripeptides were selected. The results showed that the production of pyrazines in the lysine-containing dipeptide models was higher than that in the tripeptide and control models. Compounds 2,5(6)-Dimethylpyrazine and 2,3,5-trimethylpyrazine were the main pyrazine compounds in the dipeptide models. Furthermore, the C- or N-terminal amino acids of lysine-containing dipeptides can exert an important effect on the formation of pyrazines. In dipeptide models with lysine at the C-terminus, the content of total pyrazines followed the order of Arg−Lys > His−Lys; the order of the total pyrazine content was Lys−His > Lys−Arg in dipeptide models with N-terminal lysine. Additionally, for the tripeptide models with different amino acid sequences, more pyrazines and a greater variety of pyrazines were detected in the tripeptide models with N-terminal lysine/arginine than in the tripeptide models with N-terminal histidine. However, the total pyrazine content and the percentage of pyrazines in the total volatiles were similar in the tripeptide models with the same amino acids at the N-terminus. This study clearly illustrates the ability of dipeptides and tripeptides containing lysine, arginine and histidine to form pyrazines, improving volatile formation during sunflower seed oil processing.

Effects of roasting temperature and duration on color and flavor of a sesame oligosaccharide-protein complex in a Maillard reaction model

“…Arginine as the main amino acid in SPI also showed a significant reduction. Similar results, i.e., with lysine and arginine showing significant decreases, have also been found in other studies ( Ji et al, 2019 , Wang et al, 2021 ), which further confirmed the importance of these two amino acids in color and flavor formation.…”

Physicochemical Characteristics of Bambara Groundnut Speciality Malts and Extract

“…Thus, it is an essential flavour compound in roasted food products, especially roasted coffee [ 157 ]. In addition, it is used as a flavour additive and odorant in foods such as cereals; it also occurs naturally in asparagus, green tea, crispbread, malt, raw shrimp, soya, and wheat bread [ 158 , 159 , 160 , 161 ]. Its high concentration in the BGN toasted malt could be attributed to the subjection to higher temperatures after initial drying of 50 °C.…”

“…Thus, it is an essential flavour compound in roasted food products, especially roasted coffee [157]. In addition, it is used as a flavour additive and odorant in foods such as cereals; it also occurs naturally in asparagus, green tea, crispbread, malt, raw shrimp, soya, and wheat bread [158][159][160][161]. Its high concentration in the BGN toasted malt could be attributed to the subjection to higher temperatures after initial drying of 50 • C. Methylpyrazine volatile compounds, heterocyclic volatiles, are formed by the Maillard reaction and are also common in the pyrolysis process at higher temperatures and with very low moisture contents [139,162].…”

Assessing Alkyl Methoxypyrazines as Predictors of the Potato-Taste Defect in Coffee

“…1,8 Over 800 flavor compounds in brewed coffee have been reported; however, only 20−30 aroma compounds were deemed necessary for a desirable coffee bouquet, 8 while high, nonvolatile fat content also provides a preferable note. 9 Pyrazines, partially derived from the Maillard−Strecker reaction under heating conditions that condense peptides and dicarbonyl compounds, 10,11 are among the many flavor compounds in coffee. Studies on Arabica coffee have supported their importance as flavorants.…”

“…Since cupping is the standard method of evaluating PTD in coffee along the production pipeline, the professional cuppers (for example, the Q graders used for this study) need to have high sensory sensitivity and be trained in organoleptic characterization. , Frequently, the cuppers have different sensory perceptions, which leads to varied and subjective quality scores that stem from the complex sensory notes emanating from brewed coffee. , Over 800 flavor compounds in brewed coffee have been reported; however, only 20–30 aroma compounds were deemed necessary for a desirable coffee bouquet, while high, nonvolatile fat content also provides a preferable note . Pyrazines, partially derived from the Maillard–Strecker reaction under heating conditions that condense peptides and dicarbonyl compounds, , are among the many flavor compounds in coffee. Studies on Arabica coffee have supported their importance as flavorants. , Pyrazines are significant aromatic contributors that give the characteristic pleasant odors in baked and roasted foods .…”