2.4. Syneresis measurementSyneresis measurement was executed by the method ofCharoenrein, Tatirat, and Muadklay (2008) with modification. Thetop of syringe was cut off to put into a 50 mL centrifuge tube andFig. 1. The apparatus for syneresis.about 15 holes were drilled at the bottom. Then, a part of needlewas cut down for fitting in the centrifuge tube. The equipment asillustrated in Fig. 1, was used to measure syneresis. Afterwards, thethawed gel samples were removed from syringes to those drilledsyringes with filter paper at the bottom. Next, the drilled syringeswere placed in centrifuge tubes. The tubes were then centrifuged at4000g for 15 min. The percentage of syneresis was then calculatedas the ratio of the amount of liquid separated (g) to the total weight(g) of the gel before centrifugation.