Rheological Properties, Water-Holding and Oil-Binding Capacities of Particulate β-Glucans Isolated from Spent Brewer’s Yeast by Three Different Procedures
Vlatka Petravić-Tominac1, Vesna Zechner-Krpan1*, Katarina Berković1, Petra Galović2, Zoran Herceg1, Siniša Srečec3 and Igor Špoljarić4
1Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, HR-10000 Zagreb, Croatia
2PIP d.o.o., Bijenik 158, HR-10000 Zagreb, Croatia
3Križevci College of Agriculture, M. Demerca 1, HR-48000 Križevci, Croatia
4Forensic Science Centre 'Ivan Vučetić', Ilica 335, HR-10000 Zagreb, Croatia
Article history:
Received October 13, 2010
Accepted February 3, 2011
Key words:
brewer’s yeast, oil-binding capacity, particulate β-glucan, rheology, swelling, water-holding capacity
Summary:
Particulate β-glucans were isolated from brewer’s yeast using three different procedures – alkaline (A), alkaline-acidic (AA) and alkaline-acidic with mannoprotein removal (AAM) and dried using three different methods – air drying (AD), lyophilization (L) and spray drying (SD). In this work, the obtained β-glucan preparations were tested for their microstructure, rheological properties, swelling, water-holding and oil-binding capacities. According to their rheological properties, suspensions containing 1 and 2 % (by mass) of spray-dried samples belong to the category of dilatant fluids. Among the spray-dried samples, rheological behaviour and water-holding capacity of the preparation AA-SD differed from those obtained by other two procedures (A-SD and AAM-SD). Concerning different drying methods applied, swelling was the lowest in the lyophilized samples and the most pronounced in the air-dried ones. Oil-binding capacity was the highest in the lyophilized preparations and increased proportionally to the number of processing steps applied in the isolation procedure.
*Corresponding author: 
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