The determination of bitterness analysis is a form of analysis applied in order to determine the quality criteria in processed meat products, especially roasting, olive oil and pickled olives. In these analyzes, also called Kreiss method, qualitatively bitterness is detected.

The method of determination of bitterness is based on the principle of observing the color formed by the decomposition products in the oil extracted with an organic solvent with a chemical compound solution in acidic medium. In laboratories, determination of bitterness analysis is performed using calibrated instruments and equipment.

In the determination of bitterness in food products, the oils are treated with fluoroglusinol and hydrochloric acid in ether and the bitterness values ​​of the foods are determined by oxidative determination processes. Oxidative acidity of fats and oils is determined by a quantitative evaluation and color changes caused by chemical reagents are evaluated by colorimetric measurements.

The sourness and bitterness values, together with the creis values, are handled with the concentration of the fat and the deterioration stages of food products due to oxidation can be detected earlier. Producer companies have early knowledge about their products with this method. In the light of the information obtained at the end of the laboratory analyzes, it is ensured that the products are healthy and they are used about their lifetime.

Laboratories accredited by domestic and foreign accreditation organizations comply with accepted test methods and test criteria accepted all over the world. It also operates in accordance with the standards published by many domestic and foreign organizations in measurement, analysis, testing and evaluation studies. In this way, laboratories that work with systematic and scientific methods provide more reliable and objective service and their reports are accepted all over the world.

The mentioned laboratories are also working on the determination of bitterness (Kreiss) within the scope of chemical tests.