Determining Optimal Conditions of Diacetyl Production Produced by Lactococcus Lactis Bacteria

(Samira Al-Kotami and Sayah Abou Ghorra and Sabah Yuzaji)

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Abstract

Diacetyl is considered one of the most important flavor compounds in dairy products due to its vital effects. The main objective of this study is to increase the productivity of diacetyl, which is produced by the lactic acid bacterium, Lactococcus lactis. This is done by determining the optimal conditions for its production, which can be shown using a statistics-based program called Response Surface Methodology (RSM), which was demonstrated at the Biotechnology Library ‘National Commission’ during 2019. Results reveal that the productivity of diacetyl improves by approximately 180% when the optimum conditions are applied to amounts of 65.39 mg /L. In comparison, diacetyl productivity before applying these optimal conditions only obtains a value of 36.21 mg/L. The results also reveal that the maximum quantity of produced diacetyl is 65.39 mg/L at a temperature of 37 Cº, an acidity level (PH) of 5.5, a citrate concentration at 6 g/L, and a glucose concentration of 15 g/L. The statistical analysis has shown an incorporeal relationship between temperature, acidity, citrate concentration and glucose, with a confidence level of 5%. Therefore, it is recommended that work on L. lactis bacteria should be continued to increase the productivity of diacetyl.

KEYWORDS
Flavor compounds, increase productivity, lactic acid bacteria

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References

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