No abstract

Background Quality control standards provide a quantity of microorganisms for routine use in microbiology to demonstrate the efficacy of testing methods and culture media. Standards are normally prepared by diluting a culture of microorganisms to obtain a suspension that contains an estimated number of colony‐forming units per milliliter. The variability and inaccuracy of these standards increase the potential for false results. Flow cytometry has been used extensively to prepare precise standards of Cryptosporidium and Giardia that contain exact numbers of organisms in a volume of liquid (1). However, the same levels of accuracy have yet to be obtained for bacterial quality control standards. Methods A modification of a Becton Dickinson FACScalibur flow cytometer enabled 30 bacterial cells to be sorted into a single droplet, mixed with a cryoprotective solution within the droplet, and frozen in liquid nitrogen. The frozen droplets were then freeze dried for stable preservation of the viable bacterial cells. Results A freeze‐dried sphere 3 mm in diameter was produced, which contained 30 microorganisms. The within‐batch variation for these freeze‐dried spheres was no greater than two standard deviations, and the between‐batch variation was less than one standard deviation. Conclusions Bacterial reference controls can now be produced with consistent accuracy and unparalleled precision, thus enabling harmonization across the microbiological testing industry. © 2004 Wiley‐Liss, Inc.

This study aims to identify saccharin, cyclamate, and sodium benzoate in soy milk circulating in traditional markets in the Jimbaran region, determine the percentage of soy milk samples in traditional markets in the Jimbaran region that contain saccharin, cyclamate, and sodium benzoate, and determine the characteristic of milk soybeans in the traditional markets of the Jimbaran region, Bali during storage. This study uses a survey method with saturation sampling technique. Saccharin, cyclamate and sodium benzoate were analyzed qualitatively and quantitatively while the characteristic of soy milk were observed included pH, total plate count, and sensory assessment. Saccharin, cyclamate, sodium benzoate, pH, total plate count, and sensory assessment were analyzed using descriptive methods. The results showed that soy milk in traditional markets in the Jimbaran region did not contain saccharin, 80% used cyclamate, 100% used sodium benzoate, and characteristics of soy milk in traditional markets in Jimbaran, Bali during 8 hours storage has pH between 6.8 to 8.34, as much as 70% of soy milk has total plate count less than 106 CFU/ml, and it is still well consuming because the color has the like criteria, aroma and flavor has the neutral criteria and very not acidic.

This study aims to identify saccharin, cyclamate, and sodium benzoate in soy milk circulating in traditional markets in the Jimbaran region, determine the percentage of soy milk samples in traditional markets in the Jimbaran region that contain saccharin, cyclamate, and sodium benzoate, and determine the characteristic of milk soybeans in the traditional markets of the Jimbaran region, Bali during storage. This study uses a survey method with saturation sampling technique. Saccharin, cyclamate and sodium benzoate were analyzed qualitatively and quantitatively while the characteristic of soy milk were observed included pH, total plate count, and sensory assessment. Saccharin, cyclamate, sodium benzoate, pH, total plate count, and sensory assessment were analyzed using descriptive methods. The results showed that soy milk in traditional markets in the Jimbaran region did not contain saccharin, 80% used cyclamate, 100% used sodium benzoate, and characteristics of soy milk in traditional markets in Jimbaran, Bali during 8 hours storage has pH between 6.8 to 8.34, as much as 70% of soy milk has total plate count less than 106 CFU/ml, and it is still well consuming because the color has the like criteria, aroma and flavor has the neutral criteria and very not acidic.