Antioxidant potential of Moringa Stenopetala leaf extract on lager beer stored at room temperature

Abstract

Modern breweries are focused on controlling oxidation in beer using natural antioxidants to improve shelf-life stability. The most significant quality issues in the brewing industry are flavor instability and oxidation. In this research, the effects of adding Moringa stenopetala leaf extract to lager beer at 400, 600, and 800 ppm concentrations for 30, 60, and 90 days storage at 25ºC were investigated. The total phenolic and total flavonoid content were measured by Folin-Ciocalteu and aluminum chloride method, respectively. Using the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and the phosphomolybdate assay, the antioxidant activity of each treatment was assessed and compared. Addition of the extract in beer showed a linear increment in the total phenolic content from 46.79 up to 88.30 milligram of gallic acid equivalent per liter of beer (mg GAE/L) and total flavonoid content from 123.36 up to 167.09 milligram of catechin equivalent per liter of beer (mg CE/L). Similar increment was observed within the DPPH scavenging potential, from 46.55 up to 67.16% and total antioxidant power from 139.12 up to 216.67 milligram of butylated hydroxytoluene equivalent per liter of beer (mg BHTE/L). The total phenolic and flavonoid contents and antioxidant activities of extract treated beer showed slight reduction as compared to untreated beer with increasing storage time. According to the findings, M. stenopetala leaf extract could be utilized as a component in beer to reduce oxidation and keep it fresh for extended periods of time.

Keywords:

• bioactive compounds
• lager beer
• natural antioxidant
• Moringa stenopetala

PUBLIC INTEREST STATEMENT

Beer is one of the most widely consumed alcoholic beverages in the world for its fresh taste, low calories, and higher nutritional value than other alcoholic beverages, because of its minerals content. Flavor instability resulting from beer storage and oxidation remains one of the most important quality problems in the brewing industry. Moringa is one of the most powerful sources of natural anti-oxidants by supplying the free atoms and mitigate the effect of free radicals. Furthermore, moringa has antimicrobial properties that extend the shelf life of alcoholic beverages by suppressing lactic acid bacteria. Therefore, this study deals with the possible extension of shelf life of lager beer using moringa leaf extract to replace chemical antioxidants. The incorporation of moringa stenopetala at moderate level in beer reduces oxidation and increase the phenolic content that is typically reduced during the boiling, filtration, bottling, and storage stages of the brewing process. This has a potential promise to improve the stability and shelf-life of commercial beers without the incorporation of artificial or chemical preservatives.

Acknowledgments

The authors thank BGI Ethiopia, Hawassa Brewery and School of Nutrition, Food Science, and Technology, Hawassa University, for their financial assistance and use of laboratory facilities.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The corresponding author will give the data that supports the findings of this study upon reasonable request.

Ethical approval

This study does not require ethical approval.

Additional information

Notes on contributors

Gedefaw Mazengia

Gedefaw Mazengia is a production manager at BGI Ethiopia St. George Brewery in Addis Ababa, Ethiopia. He worked as a polyvalent operator, fabrication shift leader, and production shift leader at BGI Ethiopia Hawassa brewery in Hawassa, Ethiopia.

Engeda Dessalegn

Engeda Dessalegn is an Associate Professor at the Chemistry Department, Hawassa College of Education, and also working at School of Nutrition and Food Technology, Hawassa University, Ethiopia. Research interests: Food analysis, Food preservation, and Food safety (aflatoxins and acrylamide mitigation in foods). Under his research group so far 32 Msc students have completed their research thesis and four PhD students conducting their dissertation.

Tilku Dessalegn

Tilku Dessalegn teaches Food Science and Postharvest Technology at the School of Nutrition, Food Science and Technology of the Hawassa University, Ethiopia. Among his research interests are food safety and quality, food processing and preservation, product development, and postharvest handling and technology.