Method for monitoring a liquid culture flow

Method for monitoring a liquid culture, wherein the monitoring comprises inline dilution of a flow of the liquid culture and dynamically determining a dilution factor of the liquid culture, comprising:

• providing a device (100) for inline mixing of two or more liquid flows, wherein each liquid flow is induced by a separate pump (202, 204), the device (100) comprising:
• a set (110) of inlet flow channels (112, 114) each configured for conducting a liquid flow from the separate pump (202, 204),
• a mixer (120) into which liquid from the set (110) of inlet flow channels (112, 114) enters and is mixed,
• wherein passage of liquid flow through each inlet flow channel (112, 114) effects a reduction in periodic variability in liquid flow rate,
• wherein
• each inlet flow channel (112, 114) of the set (110) is disposed with a pulsation dampener (132, 134), configured to effect the reduction in periodic variability in liquid flow rate.
• at least one inlet flow channel (110) of the set (110) of inlet flow channels (112, 114) is a liquid culture inlet flow channel (112) and conducts the liquid culture flow from the separate pump (202);
• and
• at least one inlet flow channel (110) of the set (110) is a diluent inlet flow channel (114) and conducts a diluent flow from the separate pump (204);
• diluting the liquid culture flow with the diluent flow using the device (100), thereby obtaining an inline diluted liquid culture;
• measuring a first flow rate in the liquid culture inlet flow channel (112) downstream of the pulsation dampener (132);
• measuring a second flow rate in the diluent inlet flow channel (114) downstream of the pulsation dampener (134);
• wherein:
• the dilution factor is a ratio between the sum of the first flow rate and the second flow rate, and the first flow rate, and is dynamically determined responsive to changes in the first flow rate and/or second flow rate;
• the monitoring of the liquid culture is determined from the diluted liquid culture and the dilution factor.