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Surkålens mjölksyrebakterier och deras samverkan med vårt immunförsvar

Andersson, Niclas and Högberg, Per (2009)
Food Technology
Abstract
The theme of this essay has gradually grown as a way to merge the individual courses of Food Technology, Lund University, with a special interest regarding probiotics/lactic acid bacteria (LAB). We have studied the process of fermentation in sauerkraut with a hypothesis that “LAB will, with the environmental conditions they create, compete out other microorganisms”. We compared 3 different kinds of starter cultures, their fermentative ability concerning ecologically and conventionally cultivated cabbage. Results: 1. Streptococcus thermophilus and Lactobacillus bulgaricus (from yoghurt). Both kinds of cabbage had a pH ˜ 3, 4.The fermentation was unsuccessful and the product inedible. 2. Lactobacillus plantarum 299v (from ProViva) had the... (More)
The theme of this essay has gradually grown as a way to merge the individual courses of Food Technology, Lund University, with a special interest regarding probiotics/lactic acid bacteria (LAB). We have studied the process of fermentation in sauerkraut with a hypothesis that “LAB will, with the environmental conditions they create, compete out other microorganisms”. We compared 3 different kinds of starter cultures, their fermentative ability concerning ecologically and conventionally cultivated cabbage. Results: 1. Streptococcus thermophilus and Lactobacillus bulgaricus (from yoghurt). Both kinds of cabbage had a pH ˜ 3, 4.The fermentation was unsuccessful and the product inedible. 2. Lactobacillus plantarum 299v (from ProViva) had the lowest measured pH, less than 3, 4 in both kinds of cabbage. This fermentation was successful and tasted good, 3. Natural LAB. The ecological cabbage had the highest measured pH = 5, 79.It developed other microorganisms than LAB and the sauerkraut started to putrefy, the fermentation was unsuccessful and became inedible. On the other hand, the fermentation of the conventional cabbage became successful where pH decreased to around 3, 45. The product had a good smell and tasted well. Our study consequently presented that a yoghurt culture gives a poor starter, regarding sauerkraut fermentation. 299v gave in our study a better starter culture than yoghurt. The amount of naturally existing LAB, concerning cabbage, depends on the time of harvest and time of storage. The later in autumn cabbage is harvested and the longer the storage time, the poorer the fermentative ability. These factors are of more importance than whether the cabbage is ecologically or conventionally cultivated. If existing in sufficient amount, natural LAB in our study presents good fermentors. Furthermore, it´s not the actual amount of existing LAB that decides the result of fermentation, it´s the specific ability of a bacterium. Fermentation is an ancient method of preserving and flavouring food. Many of these products would, in modern time, be considered as probiotics. Probiotics are defined by FAO and WHO as “live microorganisms which when administrated in adequate amounts confer a health benefit on the host”. The concept LAB includes bacteria preferably from the genus Lactobacillus with approximately 60 different species isolated. Most commonly used for commercial purposes, in the food industry, are Lactobacillus, Leuconostoc, Lactococcus, Streptococcus, Pediococcus and Bifidobacterium. LAB produces in the catabolic process, decomposing carbohydrates, mainly lactate and metabolites as short chain fatty acids (SCFA) which results in a decreasing pH concerning both in vitro and in vivo. LAB in vitro gives food a preserving and flavouring effect. Consumed they in vivo present a variety of positive effects in our immune defence and intestines, such as a protection against pathogenic bacteria and endotoxines, restrain of inflammation, enhances post infectional capability of recovery and increases nutritional assimilation. (Less)
Please use this url to cite or link to this publication:
author
Andersson, Niclas and Högberg, Per
organization
year
type
L2 - 2nd term paper (old degree order)
subject
keywords
surkål, mjölksyrabakterier, fermentering, immunförsvar
language
Swedish
id
1464503
date added to LUP
2009-08-19 00:00:00
date last changed
2018-10-18 10:06:58
@misc{1464503,
  abstract     = {The theme of this essay has gradually grown as a way to merge the individual courses of Food Technology, Lund University, with a special interest regarding probiotics/lactic acid bacteria (LAB). We have studied the process of fermentation in sauerkraut with a hypothesis that “LAB will, with the environmental conditions they create, compete out other microorganisms”. We compared 3 different kinds of starter cultures, their fermentative ability concerning ecologically and conventionally cultivated cabbage. Results: 1. Streptococcus thermophilus and Lactobacillus bulgaricus (from yoghurt). Both kinds of cabbage had a pH ˜ 3, 4.The fermentation was unsuccessful and the product inedible. 2. Lactobacillus plantarum 299v (from ProViva) had the lowest measured pH, less than 3, 4 in both kinds of cabbage. This fermentation was successful and tasted good, 3. Natural LAB. The ecological cabbage had the highest measured pH = 5, 79.It developed other microorganisms than LAB and the sauerkraut started to putrefy, the fermentation was unsuccessful and became inedible. On the other hand, the fermentation of the conventional cabbage became successful where pH decreased to around 3, 45. The product had a good smell and tasted well. Our study consequently presented that a yoghurt culture gives a poor starter, regarding sauerkraut fermentation. 299v gave in our study a better starter culture than yoghurt. The amount of naturally existing LAB, concerning cabbage, depends on the time of harvest and time of storage. The later in autumn cabbage is harvested and the longer the storage time, the poorer the fermentative ability. These factors are of more importance than whether the cabbage is ecologically or conventionally cultivated. If existing in sufficient amount, natural LAB in our study presents good fermentors. Furthermore, it´s not the actual amount of existing LAB that decides the result of fermentation, it´s the specific ability of a bacterium. Fermentation is an ancient method of preserving and flavouring food. Many of these products would, in modern time, be considered as probiotics. Probiotics are defined by FAO and WHO as “live microorganisms which when administrated in adequate amounts confer a health benefit on the host”. The concept LAB includes bacteria preferably from the genus Lactobacillus with approximately 60 different species isolated. Most commonly used for commercial purposes, in the food industry, are Lactobacillus, Leuconostoc, Lactococcus, Streptococcus, Pediococcus and Bifidobacterium. LAB produces in the catabolic process, decomposing carbohydrates, mainly lactate and metabolites as short chain fatty acids (SCFA) which results in a decreasing pH concerning both in vitro and in vivo. LAB in vitro gives food a preserving and flavouring effect. Consumed they in vivo present a variety of positive effects in our immune defence and intestines, such as a protection against pathogenic bacteria and endotoxines, restrain of inflammation, enhances post infectional capability of recovery and increases nutritional assimilation.},
  author       = {Andersson, Niclas and Högberg, Per},
  keyword      = {surkål,mjölksyrabakterier,fermentering,immunförsvar},
  language     = {swe},
  note         = {Student Paper},
  title        = {Surkålens mjölksyrebakterier och deras samverkan med vårt immunförsvar},
  year         = {2009},
}