Effect of Nitrite on Sausage Flavour27 September 2014
Nitrite promotes protein carbonylation and Strecker aldehyde formation in experimental fermented sausages.
A Spanish study by A. Villaverde, J. Ventanas and M. Estévez investigated whether both events are connected
The role played by curing agents (nitrite, ascorbate) on protein oxidation and Strecker aldehyde formation was studied.
In order to fulfil this objective, increasing concentrations of nitrite (0, 75 and 150 ppm) and ascorbate (0, 250 and 500 ppm) were added to sausages subjected to a 54 day drying process.
The concurrence of intense proteolysis, protein carbonylation and formation of Strecker aldehydes during processing of sausages suggests that α-aminoadipic semialdehyde (AAS) and γ-glutamic semialdehyde (GGS) may be implicated in the formation of Strecker aldehydes.
The study found that nitrite promotes protein carbonylation in fermented sausages and that the protein carbonyls may be implicated in Strecker aldehyde formation.
The fact that nitrite at an ingoing amount of 150 ppm significantly promoted the formation of protein carbonyls at early stages of processing and the subsequent formation of Strecker aldehydes provides strength to this hypothesis, the research team said.
Ascorbate (125 and 250 ppm) controlled the overall extent of protein carbonylation in sausages without declining the formation of Strecker aldehydes.
These results may contribute to understanding the chemistry fundamentals of the positive influence of nitrite on the flavour and overall acceptability of cured muscle foods.
Because of this, they said that the likely chemistry behind the impact of nitrite on flavour could be explained.
In a second study from Germany, the stability of α-tocotrienol and α-tocopherol in salami-type sausages and curing brine depending on nitrite and pH was investigated.
The research by Eva-Maria Gerling and Waldemar Ternes looked at the stability of the valuable vitamer nutrients α-tocotrienol and α-tocopherol and options for their protection in salami-type sausages (blended with α-tocotrienol-rich barley oil) and curing brine.
Four different sausage formulations were produced containing nitrite curing salt; nitrite curing salt and ascorbic acid (300 mg/kg); nitrite curing salt and carnosic acid (45 mg/kg); or sodium chloride.
Initial vitamer contents (100 mg/kg) did not decrease significantly during ripening and decreased only slightly during storage.
Ascorbic acid and carnosic acid were found to be effective in preserving the vitamers in fresh sausages.
Freeze-drying of sausages resulted in a significant loss of vitamers (97 per cent), particularly after 14-day storage at room temperature, even in the presence of shielding gases.
The vitamer content in the curing brine decreased with decreasing pH in the presence of nitrite.
A nitrite concentration of 136 mg/L at pH 4 resulted in significant loss (90 per cent) of the vitamers. Sufficient stability of the vitamers in salami-type sausage and curing brine can be achieved by processing, formulation, and storage conditions.
The findings of the research studies are published in the December issue of Meat Science.