# Functional Yogurt: Types and Health Benefits
## 2 Functional Yogurt Types
### Fortified/Added Functional Ingredient  
With the addition of various materials to yogurt, production can enhance the nutritional and functional properties [93,108]. These components can include plants, fruits, vegetables, grains, and dairy products or their bioactive contents [41,110]. These fortified materials can enhance the protein, carbohydrate, fat, vitamin, and mineral contents of the product [94]. In addition, they can also affect the physicochemical, textural, and sensory characteristics of the products [98,109,113]. Various fruits, vegetables, and grains are among the most common fortified foods added to yogurt [115,118]. The study by [PERSON] et al. aimed to demonstrate the physicochemical properties of yogurt samples with different probiotic bacterial combinations and leek addition [99]. The results revealed that increasing the lipid content generally led to increases in the antioxidant capacity and acidity. However, this addition also affected the yogurt texture. In some samples, the use of various probiotics influenced acidity and probiotic viability. Some combinations increased antioxidant activity, whereas others improved digestibility and stability. The inclusion of the leek also enhanced the texture of this group. While probiotics partially balanced these effects, overall negative impacts on stability, digestibility, and antioxidant capacity were observed. Fruits, pure fruit, seed, peel, pulp, and flour are also used as ingredients in the production of functional yogurt [40,95,103,117]. A recent study investigated the effects of adding banana pulp to yogurt produced with _Levilactobacillus brevis_ on the physicochemical, textural, and sensory properties of the product [100]. With the addition of banana pulp, the moisture content decreased, whereas the percentage of dry matter increased. The waterholding capacity significantly increased, and the degree of syneresis decreased. The samples containing uripe banana pulp had greater preferences after 15 days of cold storage. Substances classified as nutraceuticals can also be added to yogurt [96,102]. In a study investigating the effects of adding microencapsulated vitamin D to yogurt [101], the results demonstrated that the flavor score of yogurts supplemented with vitamin D was greater than that of the control yogurt, although the difference was not statistically significant. When the textures of the yogurts were compared, the yogurt with vitamin D received higher scores. In terms of overall acceptability, yogurt supplemented with added vitamin D was found to be more favorable by participants. Another study aimed to investigate the effects of various components known to potentially improve the gut microbiota and intestinal barrier functions when added to yogurt [132]. Commercially available powders of L-glutamine, quercetin, slippery elm bark, marshallow root, \(N\)-acetyl-D-glucosamine (NAG), licorice root, maitake mushroom, and zinc orotate were incorporated into yogurt. It is hypothesized that the addition of these components to yogurt could reduce intestinal issues and provide benefits. According to the pH results, the addition of L-glutamine significantly increased pH values, whereas quercetin, slippery elm bark, marshallow root, NAG, zinc orotate, maitake mushroom, and licorice root did not affect the yogurt's pH values. The titration acidity (TA) results revealed that yogurt samples containing L-glutamine and NAG had significantly lower TA values than the control yogurt, whereas the other components generally presented similar TA values. In terms of syneresis, yogurt samples containing slippery elm bark exhibited less syneresis compared to a control yogurt, while other components did not show significant differences. Similarly, the viscosity results showed that marshallow root, L-glutamine, NAG, slippery elm bark, zinc orotate, licorice root, and quercetin did not exhibit a significantly different viscosity compared to control samples, whereas maitake mushroom samples showed significantly lower viscosity.