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Enzymatic hydrolysis of cereal oil to evaluate its use as a natural emulsifier.

Montalvo Diaz, Scott LU (2019) KBTM01 20191
Biotechnology (MSc)
Biotechnology (M.Sc.Eng.)
Abstract
In this thesis the prospect of using cereal oil as a natural emulsifier after enzymatic treatment was investigated. A lipase was used in both free and immobilized form. Hydrolysis reactions were carried out using two different oil in water (O/W) emulsions. Microscopy of emulsion formation was visualized, and droplet size was obtained using a particle size distribution analyzer (PSD). Lipid extraction followed by lipid separation and acidic methylation of fatty acids (FA) was prepared. This was done in order to obtain quantitative data of the hydrolysis reaction, by using gas chromatography (GC). Enzymatic modification of one of the O/W emulsions gave unexpectedly rise to the formation of a thick emulsion that shows properties similar to... (More)
In this thesis the prospect of using cereal oil as a natural emulsifier after enzymatic treatment was investigated. A lipase was used in both free and immobilized form. Hydrolysis reactions were carried out using two different oil in water (O/W) emulsions. Microscopy of emulsion formation was visualized, and droplet size was obtained using a particle size distribution analyzer (PSD). Lipid extraction followed by lipid separation and acidic methylation of fatty acids (FA) was prepared. This was done in order to obtain quantitative data of the hydrolysis reaction, by using gas chromatography (GC). Enzymatic modification of one of the O/W emulsions gave unexpectedly rise to the formation of a thick emulsion that shows properties similar to mayonnaise. Various tests were done to assess the behavior of the emulsion, including long term incubation, temperature and pH stability.

Microscopy images of the O/W emulsions created without addition of enzyme showed small droplets. Particle size distribution showed a mean surface diameter of 5.05 ± 165 µm. However, emulsions formed using free and immobilized enzyme had a larger particle size distribution with mean surface diameter of 15.88 ± 8.62 µm and 7.03 ± 3.42, respectively for one of the O/W emulsions made. Similarly, this pattern was observed for the second O/W emulsion prepared as well. GC results were somewhat unexpected; however, it is evident that there is a difference between samples that did not contain the enzyme and those that did whether immobilized or free. Finally, different trials were made for the thick emulsion similar to mayonnaise. The PSD results that were obtained from these trials show that the thick emulsion contains relatively large droplets with mean surface diameter of 100.19 ± 20.01 µm. Formation of aggregates was observed in microscopy images. It is assumed that these aggregates have an effect in the results of the particle size analyzer. GC results show that after formation of this thick emulsion system, there is a 46% increase in released fatty acids and a decrease in polar lipids. Moreover, the emulsion seems to be stable for at least a week at room temperature, and if exposed for five minutes to temperatures below 70 °C. Addition of buffer with set pH seem to not affect this emulsion. However, addition of alkaline or acidic solution cause physical changes in the thick emulsion. It was concluded that under the settings used in this work, cereal oil has the potential to be used as a natural emulsifier. (Less)
Please use this url to cite or link to this publication:
author
Montalvo Diaz, Scott LU
supervisor
organization
course
KBTM01 20191
year
type
H2 - Master's Degree (Two Years)
subject
keywords
Biotechnology, Bioteknik
language
English
id
8986941
date added to LUP
2019-07-04 14:32:01
date last changed
2019-07-04 14:32:01
@misc{8986941,
  abstract     = {{In this thesis the prospect of using cereal oil as a natural emulsifier after enzymatic treatment was investigated. A lipase was used in both free and immobilized form. Hydrolysis reactions were carried out using two different oil in water (O/W) emulsions. Microscopy of emulsion formation was visualized, and droplet size was obtained using a particle size distribution analyzer (PSD). Lipid extraction followed by lipid separation and acidic methylation of fatty acids (FA) was prepared. This was done in order to obtain quantitative data of the hydrolysis reaction, by using gas chromatography (GC). Enzymatic modification of one of the O/W emulsions gave unexpectedly rise to the formation of a thick emulsion that shows properties similar to mayonnaise. Various tests were done to assess the behavior of the emulsion, including long term incubation, temperature and pH stability.

Microscopy images of the O/W emulsions created without addition of enzyme showed small droplets. Particle size distribution showed a mean surface diameter of 5.05 ± 165 µm. However, emulsions formed using free and immobilized enzyme had a larger particle size distribution with mean surface diameter of 15.88 ± 8.62 µm and 7.03 ± 3.42, respectively for one of the O/W emulsions made. Similarly, this pattern was observed for the second O/W emulsion prepared as well. GC results were somewhat unexpected; however, it is evident that there is a difference between samples that did not contain the enzyme and those that did whether immobilized or free. Finally, different trials were made for the thick emulsion similar to mayonnaise. The PSD results that were obtained from these trials show that the thick emulsion contains relatively large droplets with mean surface diameter of 100.19 ± 20.01 µm. Formation of aggregates was observed in microscopy images. It is assumed that these aggregates have an effect in the results of the particle size analyzer. GC results show that after formation of this thick emulsion system, there is a 46% increase in released fatty acids and a decrease in polar lipids. Moreover, the emulsion seems to be stable for at least a week at room temperature, and if exposed for five minutes to temperatures below 70 °C. Addition of buffer with set pH seem to not affect this emulsion. However, addition of alkaline or acidic solution cause physical changes in the thick emulsion. It was concluded that under the settings used in this work, cereal oil has the potential to be used as a natural emulsifier.}},
  author       = {{Montalvo Diaz, Scott}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Enzymatic hydrolysis of cereal oil to evaluate its use as a natural emulsifier.}},
  year         = {{2019}},
}