3.1.2 Influence of Process Variables . . . . . . . . . . . . . . . . . . . . . . 215
3.2 Separation of Protein Mixtures . . . . . . . . . . . . . . . . . . . . . 216
3.3 Application of Additives . . . . . . . . . . . . . . . . . . . . . . . . . 217
3.4 Protein Denaturation . . . . . . . . . . . . . . . . . . . . . . . . . . 217
3.5 Mathematical Modeling . . . . . . . . . . . . . . . . . . . . . . . . . 218
4
Flotation of Microorganisms . . . . . . . . . . . . . . . . . . . . . . 219
4.1 Flotation of Yeast Cells . . . . . . . . . . . . . . . . . . . . . . . . . . 220
4.1.1 Characterization of Process Performance . . . . . . . . . . . . . . . 220
4.1.2 Influence of Cultivation Conditions . . . . . . . . . . . . . . . . . . 222
4.1.3 Influence of Flotation Equipment,
Construction and Operational Parameters . . . . . . . . . . . . . . 223
4.1.4 Continuous Cultivation and Flotation in Pilot Equipment . . . . . . 224
4.2 Combination of Yeast Cells with Surfactants . . . . . . . . . . . . . 225
4.3 Modeling of Microbial Cell Recovery by Foam Flotation . . . . . . . 226
5
Characterization of Cells with Regard to Their Floatability . . . . . 226
6
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
List of Abbreviations
AFA
antifoam agent
BSA
bovine serum albumin
CFU
colony forming units
CMC critical micelle concentration
CPR
CO 2 production rate
DOC dissolved oxygen concentration
GUR glucose utilization rate
HBB
hemoglobin
HPMC (hydroxypropyl)methyl cellulose
IEP
isoelectric point
LB
Luria-Bertani medium
OTR
oxygen transfer rate
OUR oxygen uptake rate
PEO
poly(ethylene oxide)
POE
poly(oxyethylene)
POP
poly(oxypropylene)
PPL
potato protein liquor
RQ
respiration quotient
SPA
specific product activity
SPR
specific production rate
UDV ultrasound Doppler velocimeter
XPS
X-ray photoelectron spectroscopy
a i
interfacial area
192
K. Schügerl