Utjecaj enzimski hidrolizirane laktoze u sirutki na rast probiotičkih bakterija Lactobacillus acidophilus La-5 i Bifidobacterium animalis sups.lactis BB-12

master's thesis

• Title (english): Influence of enzymatic hydrolysis lactose in whey on growth and viability of probiotic bacteria Lactobacillus acidophilus La-5 and Bifidobacterium animalis subsp.lactis BB-12
• Author: Katarina Lisak
• Mentor: Rajka Božanić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Technology of Milk and Milk Products); Zagreb
• Defense date and country: 2009-07-14, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Sirutka je nutritivno visokovrijedan napitak koji je nedovoljno iskorišten u prehrani ljudi. Uzimajući u obzir vrijednost sirutke kao namirnice, cilj ovog rada je bio ispitati utjecaj hidrolizirane laktoze sirutke na vrijeme trajanja fermentacije probiotičkim bakterijama Lactobacillus acidophilus La-5 i Bifidobacterium animalis subsp. lactis BB-12 te na njihov rast. Laktoza je hidrolizirana enzimom ß – galaktozidazom, a fermentacija se odvijala na 37°C. Tijekom fermentacije i čuvanja praćena je pH-vrijednost, titracijska kiselost i broj živih stanica probiotičkih bakterija. Hidroliza laktoze je utjecala na smanjenje trajanja fermentacije sirutke laktobacilima, za 2 sata dok kod bifidobakterija nije bilo utjecaja. Broj živih bakterijskih stanica je na kraju fermentacije bio veći u uzorcima sa hidroliziranom laktozom fermentiranim laktobacilima (za 0,54 log10CFU/mL) i bifidobakterijama (za 0,14 log10CFU/mL) u odnosu na kontrolne uzorke. Laktobacili i bifidobakterije dobro preživljavaju u fermentiranoj sirutki te je njihov broj nakon 28 dana čuvanja iznosio od 6 do 9,8 log10CFU/mL.

Abstract (english)

Whey is nutritive valuable but poorly used in human diet. Considering the potential of whey, based on its nutritional value, the aim of this study was to define influence of enzymatic hydrolysis lactose on growth and viability of probiotic bacteria Lactobacillus acidophilus La-5 and Bifidobacterium animalis subsp.lactis BB-12. Lactose was hydrolyzed with ß – galactosidase and fermentation was conducted at 37°C. Changes of pH-values, titratable acidity and viable cells count were measured during fermentation and storage. Lactose hydrolysis influenced on decrease time of fermentation with lactobacillus (for 2 hours) and didn’t influence on time of fermentation with bifidobacterium. In comparation with control samples, viable cells count at the end of fermentation was higher for samples with hydrolyzed lactose fermented with lactobacillus (for 0,54 log10CFU/mL) and bifidobacterium (for 0,14 log10CFU/mL). Survival of lactobacillus and bifidobacterium in fermented whey after 28 days of cold storage was well and viable cell count was from 6 to 9,8 log10CFU/mL.

• Keywords: Bifidobacterium animalis subsp. lactis BB-12; fermentacija; hidroliza laktoze; Lactobacillus acidophilus La-5; sirutka
• Keywords (english): Bifidobacterium animalis subsp. lactis BB-12; fermentation; Lactobacillus acidophilus La-5; lactose hydrolysis; whey
• Language: croatian
• URN:NBN: urn:nbn:hr:159:117643
• Study programme: Title: Food Technology; specializations in: Food Engineering; Course: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo (diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-01 07:20:05