**6. MFGM in dairy based functional foods**

As supplementation of MFGM is popularized in IFs, it also gained interest in incorporating dairy products like yoghurt, cheese and dairy beverages. Incorporation of MFGM in skim milk yoghurt from 1 to 4% (w/w) total solids concentration increased the firmness, water holding capacity and adhesiveness. Addition of MFGM also improved the concentration of polar lipids and protein content (including casein) (5.3% MFGM yoghurt *vs* 4.08% control). Below 3% of MFGM solids the gel strength was slightly weaker but increased when added above 3%. Similarly, firmness also decreased when yoghurt has 1% MFGM solid due to prevention of contraction of casein during curd formation.

Overall quality of the MFGM supplemented yoghurt was superior and shows the technological applications like water holding capacity [82]. Cohort study in yoghurt was done by [83], homogenized and unhomogenized set yoghurt were prepared with 4% Lacprodan®PL-20 with addition 0f 0.5% yoghurt culture with final total solids content of 15%. During homogenization, the surface area of the MFGM gets decreased and due to its polarity the affinity between PL and milk protein increases resulting in improved body and texture of the set yoghurt. The authors commented that addition of MFGM in yoghurt prevents the physical defects and improves the health benefits of the product.

Since MFGM is an amphiphilic molecule, it can be used as a stabilizer in dairy products to avoid the usage of artificial stabilizers to improve the quality of the product. Beyond the use of MFGM as a technological ingredient, MFGM was also used to encapsulate the lactic acid bacteria (LAB). Study on interaction between MFGM and LAB revealed that most of the bacteria are located at whey protein-fat interface or trapped in MFGM in the food matrix. Even after ripening, the bacteria are found to be trapped in MFGM [84–86]. This interaction was probably due to the reaction between bacteria and mucin factor of MFGM [87]. These studies clearly depict the encapsulation efficacy of natural ingredient MFGM as an emulsifier for LAB culture, especially in the location of bacteria on the surface of the cheese matrix. Further investigation on microstructure of MFGM material in cheese could be advantageous in improving flavor and color (in blue veined cheese) in cheese for the higher consumer preference.

Most recently, development of oil-in-water food emulsions are being prevalent due to their emulsion stability and protection against the oxidation of lipids. Likewise, MFGM coated lipid systems are studied to mimic the human fat globule to deliver the health benefits notably in IFs. The process involved in coating of MFGM around the triacylglycerol (TAG) through higher pressure homogenization methods [88]. Not only in IFs, these types of emulsions can be used in various products ranging from cheese, cream and dairy beverages irrespective of the consumer age. This concept

of emulsion leads to the production of commercial MFGM –PL (from beta serum or butter serum) coated vegetable oil in IMF called Nuturis®. This novel formula was prepared by mixing bovine PL (0.5 g PL in one liter) from beta serum in the aqueous phase of formula containing other ingredients and heating for 85°C/6 min, followed by homogenization with lipid phase (vegetable oil mixture) in inline mixer to form larger fat droplets coated with phospholipid. The microscopic examination showed that the fat droplet size and the location of cholesterol exposure were more or less similar to the human milk. This regulates the uptake of cholesterol in early childhood that maintains the weight gain and loss similar to the human milk intake [89]. This proves that MFGM and its fractions are important in emulsion formation because of their emulsifying capacity and physical stability due to their complex formation while processing.

In conclusion, deeper knowledge on human milk morphology and characterization of distribution of lipid will lead to develop novel and more innovative technologically significant functional food for the infant nutrition to reduce the incidence of overweight and obesity in early stages of childhood which was considered to be most prominent problem encountered while ingestion of other infant formula with imbalanced concept of nutrition.
