Chloride Content of Food— Potentiometric Titration Method

The REX Ti-50 Automatic Potential Titrator allows quick and simple determinations of the chloride content of milk, milk products, infant formula, adult nutritionals, cheese, processed cheese products, meat and meat products.

Chlorine is one of the essential constants of human body, which is necessary to maintain the balance of body fluids and electrolytes.

In the Infant formula，add chlorine in milk powder to avoid the loss of sodium and potassium ions, maintain the balance of potassium and sodium nutrients, adjust the body's acid and alkali, to ensure the healthy growth of children.

 It is is not good for human health when long-term consumption of high salt content food. It is necessary to determine the chloride content of cheese products，because it requires the addition of salt in the fermentation. It is necessary to determine the chloride content of cheese products，because it requires the addition of salt in the processing. All kinds of food also contain chlorine，the chloride content should be in reasonable range.

1. Standard Reference

ISO 21422:2018 | IDF 242:2018 Milk, milk products, infant formula and adult nutritionals — Determination of chloride — Potentiometric titration method

ISO 5943|IDF 88:2006 Cheese and processed cheese products — Determination of chloride content — Potentiometric titration method

ISO 1841-2:1996 Meat and meat products — Determination of chloride content — Part 2: Potentiometric method

ISO 21422:2018 | IDF 242:2018 specifies a method for the determination of chloride in milk, milk products, infant formula and adult nutritionals by potentiometry with an analytical range of 0,35 mg chloride/100 g to 711,6 mg chloride/100 g product, or ready-to-feed products.

ISO 5943|IDF 88:2006 specifies a potentiometric titration method for the determination of the chloride content of cheese and processed cheese products. It is applicable to all cheeses and processed cheese products containing more than 0,2 % (mass fraction) of chloride ion.

ISO 1841-2:1996 gives a method for the determination of the chloride content of meat and meat products, including poultry, with sodium chloride contents equal to or greater than 0,25 % (m/m).

2. The Principle

Chloride is extracted from samples by mixing in warm water, or directly from ready-to-feed (RTF) products. After (optional) precipitation of proteins, chloride ions are titrated with standardized AgNO₃ solution potentiometrically, using a silver electrode to detect the end point.

3. Recommended Configuration

• Ti-50 Automatic Potential Titrator 
• Range：(-2000.00~2000.00) mV
• mV Accuracy：±0.03% or ±0.2mV
• Support acid-base titration, non-aqueous aqueous phase titration, constant titration, REDOX titration, precipitation titration, complexation titration
• Support the following titration modes: DET (dynamic equivalence point titration), MET (monotone equivalence point titration), SET (Preset Endpoint Titration) and MAT (manual titration).
• Titration methods, curves and results are displayed in detail.
• Includes 217-01 reference electrode

• Electrodes
• 981121 Silver titration electrode
• 217-01 reference electrode（The filling solution needs to change to saturated Sodium nitrate solution）

4. Titration Setting

• Precipitation titration
• Sample: DET (dynamic equivalence point titration)
• Blank Sample: MET (monotone equivalence point titration)

5. Titration curve