Determination of Acidity in Yogurt According to TS 1330 Standard: Analysis Methods

TS 1330 - Yogurt - Acidity Determination

Yogurt is a fermented dairy product that remains durable for a long time by preventing the growth of many microorganisms thanks to its acidic structure. However, one of the most important factors determining the quality, flavor and shelf life of yogurt is its acidity level. Acidity is also a critical measure to understand whether yogurt has undergone the correct fermentation process. In Turkey, quality control in yogurt production is carried out in accordance with the Turkish Standard TS 1330.

Why is acidity important in yogurt?

The acidity of yogurt is caused by the conversion of milk sugar (lactose) into lactic acid during the fermentation process. This process, carried out by lactic acid bacteria, gives yogurt its distinctive sour taste and consistency. Levels of acidity in yogurt can affect quality and health safety:

Flavor and Texture: High acidity can make yogurt too sour, while low acidity can lead to a bland texture.
Shelf Life: The right acidity level contributes to yogurt being able to be stored for a long time without spoiling.
Microbiological Safety: Acidity prevents the growth of pathogenic microorganisms in yogurt, ensuring safe consumption.

What is TS 1330 Standard?

TS 1330 is a standard prepared by the Turkish Standards Institute (TSE) that determines the quality and properties of yogurt. This standard covers the physical, chemical and microbiological properties of yogurt and sets important criteria to ensure quality control of the production process. The TS 1330 standard includes yogurt content, sensory requirements and yogurt analysis. According to the TS 1330 standard, yogurt to be offered to consumers must meet the following conditions. Determination of acidity in yogurt (in soxhlet-henkel-SH) is based on the following analysis principle:

The sample is thoroughly mixed, 10 g is weighed into a beaker.
Add 10 ml of pure water boiled and cooled to 40°C to the sample and mix well with a glass beaker.
Add 0.5 ml of phenolphthalein solution.
Titrate with 0.25 N sodium hydroxide solution for at least 30 seconds. A persistent slightly pink color should appear.
To find the acidity of 100 g yogurt, the amount of sodium hydroxide used is multiplied by 10 and found as °SH.

% Acidity= SHx0,0225

What should be the acidity ratio in yogurt?

According to the Foodstuffs Regulation and TS 1330 Yogurt Standard, it should be at least 0.8% - 1.6% by mass in terms of lactic acid.
According to the Turkish Food Codex Communiqué on Fermented Milk, this value should be at least 0.6%.

Nano-lab Laboratories Group continues to provide services within the scope of Determination of Acidity in Yogurt. We also provide services on Imitation and Adulteration in Yogurt.

You can follow us on LinkedIn for up-to-date news and posts about our services.

Follow our Instagram account to be informed about our latest blog posts.