The total amount of sulfur dioxide in wines is determined by redox titration with iodine as a titrant. Two techniques are illustrated: (1) the voltametric indication with a platinum double-pin polarized electrode, and (2) the standard potentiometric indication with a combined platinum ring electrode.
The analysis dicusses thermometric titration as a promising method for the straightforward sodium determination in foodstuffs. Thermometric sodium titration was tested for its applicability to various food matrices such as soups, gravy and several salty snacks. Enthalpy change can be monitored as a change in temperature of the solution using a sensitive digital thermometer.
Application note L 492 provides a method for determining the water content in hand cream (hand balm).
A method for the determination of the free fatty acids (FFA) content in edible oil by potentiometric titration with ethanolic potassium hydroxide in a non-aqueous mixture consisting of ethanol and diethylether (1:1 v/v) is presented.
The thermometric titration method presented here permits a simple and direct determination of the total acid number (TAN) in petroleum products.
This introduction to Karl Fischer Titration shows how this classic technique provides a reliable and truly practical method for the determination of water content.
What is the acetic acid content of the vinegar in front of you? For most of our readers it was probably the first contact they had with chemistry when they had to answer this question. There was a lot to learn from this simple experiment. In most experiments we ask for an assay and want to have a result as a content in numbers.
In this issue, the author looks at the importance of pharamcopeias in providing established methods and the advantages that they provide.
Titration Solutions #3: Automatic Determination of Alpha Acids in Hop Extracts Using Conductometric Titration
The hop vine is a species of plant belonging to the hemp family. The high content of alpha acids (bitter substances) in hops makes it an essential ingredient in beer brewing. Variation of the amount added has a decisive influence on the taste of the beer.
A high resolution pulsating sensor-based conductometric titration for the determination of alkalinity in water is presented. The titration, including an online graphic display of the titration plot and offline analysis of data to obtain information regarding the end point is completed in less than 500 s. Quantitative information of various species present in the sample is obtained from the titration plot. The results obtained from the proposed technique have been compared with those obtained from pH titration.
Calibration, validation and control of analytical instruments and reagents are central requirements in most quality management systems. In the case of Karl Fischer (KF) titration, regular titer determination, control of measurement precision and accuracy, as well as validation and inspection of the instrument are of fundamental importance.
When you have to do an analytical experiment the first thing to do is always to ask if others done the same thing before. You may consider standard works or look at literature on- or offline. Maybe you don’t find the recipe for your exact substance but you study a similar one. At the end you see that you have to develop a new method and validate it also. Nevertheless some of the following points apply to standard methods or to new ones.
The rapid growth in the world population has led to sharp increases in the consumption of energy and resources and in the production of consumer goods and chemicals. It is estimated that there are a total of 17 million chemical compounds on the market, including as many as 100,000 that are produced on a large industrial scale. A lot of these compounds enter the environment and have to be analysed.
Titration Solutions #8: Conductometric Titration: Practical Solutions for Locating the Equivalence Point
It was in 1930 when I. M. Kolthoff wrote his review article “Conductometric Titrations” in which he highlighted the need for implementing conductometry in more applications than was the case at that time. Offering advantages to analytical chemists compared with other titrimetric procedures, conductometry is currently widely used in many applications including, but not limited to, pharmaceutical analysis.
The presence of excessive water in plastics adversely affects the performance of polymeric goods which is why water determination is of crucial importance. This article describes the accurate and straightforward determination of the water content using the Karl Fischer Oven Method in ten different plastic types that are not amenable to direct Karl Fischer titration.
For the production of milk and dairy products, the water content plays an important role, technologically as well as economically. Therefore, national and international laws and agreements protect and regulate the definition of products and the production processes in dairy technology. Determining the water content in milk and milk products can be easily achieved with Karl Fischer (KF) titration.