What are the factors influencing the stability of vitamin C in acerola cherries in yogurt?

Vitamin C belongs to the exogenous antioxidants, proper supplementation of some exogenous antioxidants is a guarantee to be able to maintain a healthy state on a regular basis. In addition to its antioxidant effects, vitamin C is also known to promote growth and development, enhance immunity, promote iron absorption, and prevent colds and flu in outdoorsy people.
Acerola cherries, commonly known as West Indian cherries, are rich in vitamin C, of which the mass fraction of vitamin C is as high as 1,215 to 3,024 mg/kg, making them an excellent natural source of vitamin C.
In the Chinese dairy market, it is rare to see yogurt fortified with vitamin C. Sucrose added to yogurt to neutralize the sour taste has a protective effect on vitamin C. In addition, the lower the pH, the more stable vitamin C is.
This paper investigates the stability of vitamin C in acerola cherries in yogurt with the aim of providing ideas for the development of nutrient-fortified and clean-labeled products.
Effect of different packaging forms on vitamin C in yogurt
Due to the different oxygen and light transmission rates of the three packaging forms, the post-cooked yogurt was divided into different packaging forms and stored in the light at a low temperature of 2～6℃ for 2O days for the determination of vitamin C content, and the results are shown in Table 1:

As can be seen from Table 1, the loss of vitamin C content in glass and PE bottles was small, while the loss of vitamin C in black and white film bags reached 30.77%. It may be due to the higher oxygen permeability of the black and white film bags that vitamin C is easily inactivated by oxidation.
Effect of different storage temperatures on vitamin C in yogurt
In order to verify the effect of temperature on the stability of vitamin C, the post-cooked yogurt was divided into PE bottles and placed in 2-6℃ and room temperature conditions (20-30℃) for the determination of vitamin C mass fraction, and the results are shown in Table 2.

As can be seen from Table 2, the loss of vitamin C in yogurt under low temperature conditions from 2 to 6°C was smaller 15.38%, and under ambient conditions, the loss of vitamin C amounted to 84.25%, indicating that the ambient conditions (20-30°C ) have a greater effect on the stability of vitamin C. Stability of vitamin C in shelf-life yogurt
The yogurt was dispensed in PE bottles and placed in a refrigerator at 2~6°C for 21 d. The vitamin C mass fraction was examined every 3 days, and the results are shown in Fig. 1.

 

As can be seen in Fig. 1, the vitamin C content of yogurt decreases with the increase in storage time, and the loss of vitamin C was 18.25% on the 21st day.
Summarization

The study showed that the loss of vitamin C in yogurt with acerola cherry powder during shelf life was 18.25%. The best stability of vitamin C was found in yogurt packed in glass and PE bottles with a loss rate of 7.69% and 15.38%, respectively, and in black and white film with a loss rate of 30.77%.
The storage temperature has a greater impact on the stability of vitamin C. The loss rate of vitamin C reaches 84.25% at room temperature, and the color changes.
Therefore, when developing yogurt containing vitamin C, packaging forms with lower oxygen permeability such as glass and PE bottles should be considered. After purchasing yogurt products, consumers should store them in a refrigerator at 2 to 6°C to avoid loss of nutrients.