Protein content in Brewer’s spent grain and its characteristics : upcycling spent grain from food waste to protein source
The United Nations have adopted sustainable development goals (SDGs). Within these SDGs, food waste management and waste valorization, an increase in value, is found. For these reasons, it was of interest to study Brewers’ spent grain, a residual product from beer production. In 2020 beer was one of...
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| Formato: | H2 |
| Lenguaje: | Inglés sueco |
| Publicado: |
SLU/Department of Molecular Sciences
2022
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| Materias: |
| _version_ | 1855573008026959872 |
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| author | Rönnhagen, Moa |
| author_browse | Rönnhagen, Moa |
| author_facet | Rönnhagen, Moa |
| author_sort | Rönnhagen, Moa |
| collection | Epsilon Archive for Student Projects |
| description | The United Nations have adopted sustainable development goals (SDGs). Within these SDGs, food waste management and waste valorization, an increase in value, is found. For these reasons, it was of interest to study Brewers’ spent grain, a residual product from beer production. In 2020 beer was one of the largest categories among the production of alcoholic beverages and Brewers’ Spent grain (BSG) was one of the largest sources of waste in beer production.
This study aimed to extract protein from two variants of BSG, dried at different temperatures, and to study some of the protein characteristics. The protein extraction was an alkali-soluble and acid precipitation and was performed in variations. The extraction was most successful when using an alkaline concentration of 55 mM (NaOH) and a pH of 3.8 when isoelectric precipitation was performed. Concentration measurements of the proteins in the precipitates were made through Bradford analysis and for two samples using Kjeldahl analysis. At the most, the concentrations of protein showed to be 53.50% for the BSG dried at 50-60°C, results obtained from a Kjeldahl analysis.
For the characterization, SDS-gels, gel filtration, foaming, gelation, and protein nanofibrilation (PNF) was carried out. The results from the SDS-gel and gel filtration showed indications of protein (or complex) of sizes > 200 kDa. The obtained proteins showed abilities to form gel and foam, but the stability and ability were questionable as the precipitates were not only pure protein. For the same reason, the results of the ability to form PNFs were difficult to draw any conclusions from.
In conclusion protein from the BSG in question was able to be extracted. The precipitates showed the ability to form gel and foams, with varying desirable characteristics. Judging by the protein concentrations obtained in the precipitates and total protein content in the BSG, the use of protein as a valorization may not be the answer. |
| format | H2 |
| id | RepoSLU18116 |
| institution | Swedish University of Agricultural Sciences |
| language | Inglés swe |
| publishDate | 2022 |
| publishDateSort | 2022 |
| publisher | SLU/Department of Molecular Sciences |
| publisherStr | SLU/Department of Molecular Sciences |
| record_format | eprints |
| spelling | RepoSLU181162022-08-12T01:01:28Z Protein content in Brewer’s spent grain and its characteristics : upcycling spent grain from food waste to protein source Proteininnehåll hos drav och dess egenskaper : upcycling av drav från livsmedelsavfall till proteinkälla. Moa Rönnhagen Rönnhagen, Moa Barley food waste brewers’ spent grain beer protein extraction characterization future food The United Nations have adopted sustainable development goals (SDGs). Within these SDGs, food waste management and waste valorization, an increase in value, is found. For these reasons, it was of interest to study Brewers’ spent grain, a residual product from beer production. In 2020 beer was one of the largest categories among the production of alcoholic beverages and Brewers’ Spent grain (BSG) was one of the largest sources of waste in beer production. This study aimed to extract protein from two variants of BSG, dried at different temperatures, and to study some of the protein characteristics. The protein extraction was an alkali-soluble and acid precipitation and was performed in variations. The extraction was most successful when using an alkaline concentration of 55 mM (NaOH) and a pH of 3.8 when isoelectric precipitation was performed. Concentration measurements of the proteins in the precipitates were made through Bradford analysis and for two samples using Kjeldahl analysis. At the most, the concentrations of protein showed to be 53.50% for the BSG dried at 50-60°C, results obtained from a Kjeldahl analysis. For the characterization, SDS-gels, gel filtration, foaming, gelation, and protein nanofibrilation (PNF) was carried out. The results from the SDS-gel and gel filtration showed indications of protein (or complex) of sizes > 200 kDa. The obtained proteins showed abilities to form gel and foam, but the stability and ability were questionable as the precipitates were not only pure protein. For the same reason, the results of the ability to form PNFs were difficult to draw any conclusions from. In conclusion protein from the BSG in question was able to be extracted. The precipitates showed the ability to form gel and foams, with varying desirable characteristics. Judging by the protein concentrations obtained in the precipitates and total protein content in the BSG, the use of protein as a valorization may not be the answer. FN har antagit mål för hållbar utveckling. Inom dessa globala hållbarhetsmål hittas ämnen som matsvinnshantering och värdeökning av avfall. I och med dessa mål var det av intresse att studera drav, en restprodukt från ölproduktion. År 2020 var öl en av de största kategorierna inom produktion av alkoholdrycker och drav en av de största källorna till avfall i ölproduktionen. Denna studie syftade till att extrahera protein från två varianter av BSG, torkat vid olika temperaturer och att studera några av proteinets egenskaper. Proteinextraktionen var en alkalilöslig och sur utfällning, som utfördes i variationer. Extraktionen var mest lyckad när man använde en alkalisk koncentration om 55 mM (NaOH) och ett pH på 3,8 när isoelektrisk utfällning utfördes. Proteinkoncentrationerna i utfällningarna bestämdes med hjälp av en Bradford-analys och för två prover med användning av en Kjeldahl-analys. Som mest var koncentrationen av protein 53,50 % för dravet torkat vid 50-60°C och framtaget genom Kjeldahl-analys. För karakteriseringen utfördes SDS-geler, gelfiltrering, skumning, gelning och försök till protein-nanofibriller (PNF). Resultaten från SDS-gelen och gelfiltreringen visade tecken på protein (eller komplex) med storlekar på > 200 kDa. De erhållna proteinerna kunde bilda gel och skum, men stabiliteten och förmågan var tveksam då fällningarna inte bara var rent protein. Av samma anledning var resultaten av förmågan att bilda PNF svåra att dra några slutsatser kring. Sammanfattningsvis var det möjligt att extrahera protein från dravet i studien. Fällningarna visade egenskaper som att bilda gel och skum, med varierande grad av användbarhet. Att döma av de proteinkoncentrationer som erhållits i utfällningarna och det teoretiska proteininnehållet i dravet, kanske inte användningen av protein som värdeökning är svaret. SLU/Department of Molecular Sciences 2022 H2 eng swe https://stud.epsilon.slu.se/18116/ |
| spellingShingle | Barley food waste brewers’ spent grain beer protein extraction characterization future food Rönnhagen, Moa Protein content in Brewer’s spent grain and its characteristics : upcycling spent grain from food waste to protein source |
| title | Protein content in Brewer’s spent grain and its characteristics : upcycling spent grain from food waste to protein source |
| title_full | Protein content in Brewer’s spent grain and its characteristics : upcycling spent grain from food waste to protein source |
| title_fullStr | Protein content in Brewer’s spent grain and its characteristics : upcycling spent grain from food waste to protein source |
| title_full_unstemmed | Protein content in Brewer’s spent grain and its characteristics : upcycling spent grain from food waste to protein source |
| title_short | Protein content in Brewer’s spent grain and its characteristics : upcycling spent grain from food waste to protein source |
| title_sort | protein content in brewer’s spent grain and its characteristics : upcycling spent grain from food waste to protein source |
| topic | Barley food waste brewers’ spent grain beer protein extraction characterization future food |