Öz
The research was carried out in order to determine the chemical properties of yoghurt, whose production has increased in Istanbul in recent years, during the storage period and the presence of additives, and to reveal the quality characteristics of the yoghurt produced.
In Istanbul region, 10 different brands and 10 samples of each brand were brought to the laboratory with their original packages, which were offered for sale in packages of 500-1500 g with a full-fat yoghurt label. The samples brought to the laboratory were kept at +4 °C and analyzed within 24 hours. On the 1st day of storage, samples were examined for the presence of gelatin, starch and peroxidase, and on the 1st, 7th and 14th days of storage for their chemical properties (fat, protein, acidity [1.a%] and non-fat dry matter).
The analysis results of the samples were evaluated during the storage period, especially considering the criteria specified in the Turkish Food Codex (TFC). It was determined that all of the samples were suitable in terms of protein amounts, starch and peroxidase test results. On the other hand, all of the samples in terms of fat amounts, 10% of the samples 1st and 7th days of the storage in terms of acidity (1.a%) values were not appropriate. However, it was determined that 90% of the samples did not comply with the relevant criterion in terms of the amount of non-fat dry matter specified in TS 1330. In addition, it has been concluded that 20% of the samples contain gelatin, which is prohibited according to TFC, and that there is no statistically significant difference between the chemical properties of the samples containing gelatin and samples that do not contain it during storage.
As a result, it has been determined that yoghurts produced by some dairy enterprises do not comply with legal chemical criteria and / or contain gelatin. It is important to carry out the relevant controls routinely and take precautions for the production of yoghurt with superior and legal qualities.