In order to create a calibration curve for the rheological measurements, W/O emulsions of various dispersed phase concentrations were necessary. Firstly, a concentrated W/O emulsion was prepared by dispersing 60% w/w of the aqueous phase (W-1 from Table 1) into the oily phase (37% w/w oil and 3% w/w PGPR). 120 g of the oil phase was given into a glass beaker (1000 ml volume) and agitated by a propeller stirrer (R 1382, IKA®-Werke GmbH & Co. KG, Staufen, Germany) at 120 rpm. 280 g of heated aqueous phase (prepared according to 4.2) were added as a thin jet over 1 min and the emulsion was stirred for 1 min. The concentrated emulsion was then diluted to the desired dispersed phase by mixing appropriate amounts of emulsion and oil phase.