Hanna HI98164 Portable pH Meter (pH/mV/Temp) Waterproof USB Glass Electrode for Semi-Solids

The HI98164 pH meter comes with all the necessary accessories for pH/temperature measurement in a robust, carrying case that keeps the meters, probes, and calibration solutions safe.

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pH monitoring is crucial in the process of making consistent, high-quality yogurt. Yogurt is made by fermenting milk with live bacterial cultures. Most yogurts are inoculated with a starter culture consisting of Lactobacillus bulgaricus and Streptococcus thermophilus.

Once the live culture is added, the milk and bacteria mixture is incubated, allowing the lactose to ferment into lactic acid. The pH of the mixture decreases and becomes more acidic due to the production of lactic acid. Yogurt products stop germinating once they reach a specific pH level. Most producers have a desired pH point between 4.0 and 4.6 at which fermentation is stopped by rapid cooling. Within this pH range, there is an ideal amount of liquid acid for yogurt, giving it the proper characteristics, aiding in thickening, and acting as a preservative against undesirable strains of bacteria. By ensuring that fermentation continues to a predetermined pH endpoint, yogurt producers can guarantee that their products remain consistent in terms of flavor, aroma, and texture. A pH deviation can contribute to a shorter shelf life for the yogurt or create a product that is too bitter or acidic. Syneresis can also occur if fermentation is too early or too late, resulting in a yogurt that is, respectively, too alkaline or too acidic. Synesis is the separation of the liquid, in this case whey, from the milk solids. Consumers expect yogurt to have a consistent texture, so they ensure that fermentation stops at the appropriate pH for their perception. Yogurt can present a number of challenges for anyone needing to measure pH. Yogurt is a semi-solid with a very high solids content. This type of sample coats the sensitive surface of the membrane and obstructs the reference junction. The FC2133 can be used with the HI98164, which is specifically designed to measure pH in yogurt. From a pointed tip for easy penetration to an open junction that resists clogging, the FC2133 is an ideal pH electrode for general use in yogurt. The FC2133 connects to the HI98164 with a quick-connect, waterproof DIN connector, allowing for a secure, threadless attachment. This pH meter meets FDA Food Safety Modernization Act (FSMA) compliance standards. The FC2133 pH electrode is a tool that offers many features that improve pH testing for yogurt producers. A body temperature sensor allows for temperature-compensated pH measurements without the need for a separate temperature probe. An integral part of any pH electrode is the reference junction. The reference junction is the part of the electrode that allows the flow of signals into the reference cell within the sample being tested. This flow is vital to complete an electrical circuit, which ultimately determines the pH value. Any obstruction of the junction will prevent the circuit from completing, resulting in erroneous or inaccurate readings.