The HI84529-50 is a 120 mL bottle of alkaline titrant solution used for the Low Range 20 range that determines 0.01 to 0.20% lactic acid in dairy products.The methodology for titratable acidity in dairy products is based on a neutralization reaction of the acids in a sample (e.g., lactic acid) with a base (e.g., sodium hydroxide) to produce water:H++OH– → H2OIn an ideal solution, the endpoint of an acid titration corresponds stoichiometrically to the complete neutralization of the acids present. The endpoint for this reaction can be determined visually using a color indicator (e.g., phenolphthalein); however, this endpoint becomes very subjective in opaque and colored samples such as milk. The HI84529 removes this issue by titrating to a fixed pH endpoint that is potentiometrically determined by the FC260B half-cell pH electrode and HI5315 half-cell reference electrode.Replacement reagents required to operate the HI84529 include:
| Low Range 20 (LR 20) – %l.a.: 0.01 to 0.20 | Low Range 50 (LR 50) – %l.a.: 0.01 to 0.20 | High Range 20 (HR 20) – %l.a.: 0.1 to 2.0 | |
| Pump calibration standard | HI84529-55 | HI84529-55 | HI84529-55 |
| Titrant solution | HI84529-50 | HI84529-52 | HI84529-51 |
