Item no. HI-99164
The Hanna Instruments HI99164 is a durable, waterproof, and portable pH and temperature meter designed specifically for yogurt analysis. Automatic calibration is performed at one or two points with two sets of buffers. All calibration and measurement readings are automatically compensated for temperature variations. The split-level LCD displays both pH and temperature readings, along with indicators for reading stability, battery percentage, and calibration instructions. The HI99164 uses the FC213D glass body, amplified pH electrode that offers numerous features that improve pH testing for yogurt producers.
Automatic Temperature Compensation
Automatic, one or two-point calibration
Monitoring pH is crucial in producing consistent, quality yogurt. Yogurt is made by the fermentation of milk with live bacterial cultures. Most yogurt is inoculated with a starter culture consisting of Lactobacillus bulgaricus and Streptococcus thermophilus. Once the live culture is added, the mixture of milk and bacteria is incubated, allowing for fermentation of lactose to lactic acid. The pH of the mixture drops and becomes more acidic due to the lactic acid production; it is this reduction in pH causes the casein protein in milk to coagulate and precipitate, resulting in a yogurt-like texture.
Yogurt producers cease incubation once a specific pH level is reached. Most producers have a desired point between pH 4.0 and 4.6 in which fermentation is stopped by rapid cooling. Within this range of pH there is an ideal amount of lactic acid present for yogurt, giving it the characteristic tartness, aiding in thickening, and acting as a preservative against undesirable strains of bacteria.
By verifying that fermentation continues to a predetermined pH endpoint, yogurt producers can ensure their products remain consistent in terms of flavor, aroma, and texture. A deviation from the predetermined pH can lead to a reduced shelf life of yogurt or create a product that is too bitter or tart. Syneresis can also occur if fermentation is stopped too early or too late, resulting in yogurt that is respectively too alkaline or too acidic. Syneresis is the separation of liquid, in this case whey, from the milk solids. Consumers expect yogurt to remain texturally consistent, so ensuring fermentation is stopped at the appropriate pH is vital to consumer perception.
Waterproof - The HI99164 is a waterproof meter rated IP67 for immersion in up to one meter of water for 30 minutes.
Automatic Calibration - One or two-point calibration is automatic to two selectable buffer sets.
Automatic Temperature Compensation – An integrated temperature sensor allows for automatic temperature compensation of pH measurements.
Multi-Level LCD Display - The split-level LCD displays both pH and temperature readings, along with indicators for reading stability, battery percentage, and calibration instructions.
On-Screen Tutorial - Clear tutorial messages and directions are available on-screen to quickly and easily guide users through setup and calibration.
Battery Error Prevention System - The meter will automatically shut off if there isn’t enough power to obtain an accurate measurement.
Battery Life Indicator - The battery percent level is displayed at start up alerting the user to the remaining battery power that is available.
HI99164 is supplied with FC213D pH probe with internal temperature sensor, batteries, instruction manual, and rugged carrying case.
|Battery Type/Life||1.5V (3) AAA / approximately 1200 hours of continuous use; auto-off after 8 minutes of non-use|
|Dimensions||152 x 58 x 30 mm (6.0 x 2.3 x 1.2”)|
|Electrode/Probe||FC213D pre-amplified pH probe with internal temperature sensor, DIN connector and 1 m (3.3’) cable (included)|
|Environment||0 to 50°C (32 to 122°F); RH max 100%|
|pH Accuracy||±0.02 pH|
|pH Calibration||automatic, at one or two points with two sets of standard buffers (pH 4.01 / 7.01 / 10.01 or pH 4.01 / 6.86 / 9.18)|
|pH Range||-2.00 to 16.00 pH|
|pH Resolution||0.01 pH|
|Temperature Accuracy||±0.5°C (up to 60°C); ±1.0°C (outside) / ±1°F (up to 140°F); ±2.0°F (outside)|
|Temperature Compensation||automatic from -5.0 to 105.0ºC (23 to 221ºF)|
|Temperature Range||-5.0 to 105.0°C / 23.0 to 221.0°F|
|Temperature Resolution||0.1°C / 0.1°F|
|Weight||205 g (7.2 oz.)|