Conventional and Innovative Processing of Milk for Yogurt Manufacture; Development of Texture and Flavor: A Review

Abstract

Milk and yogurt are important elements of the human diet, due to their high nutritional value and their appealing sensory properties. During milk processing (homogenization, pasteurization) and further yogurt manufacture (fermentation) physicochemical changes occur that affect the flavor and texture of these products while the development of standardized processes contributes to the development of desirable textural and flavor characteristics. The processes that take place during milk processing and yogurt manufacture with conventional industrial methods, as well as with innovative methods currently proposed (ultra-high pressure, ultrasound, microfluidization, pulsed electric fields), and their effect on the texture and flavor of the final conventional or probiotic/prebiotic products will be presented in this review.

Effect of High Pressure Homogenization on Improving the Quality of Milk and Sensory Properties of Yogurt: A Review

“…However, the effect of pressure on the size and distribution of fat globules starts at 50 °C. Below this temperature no changes has occurred due to the stability of the fat particles membrane [1].…”

“…Also, centrifuges are used to separate cream from skim milk and after that pasteurization (usually 72 ° C for 15 seconds), is applied to destroy harmful microorganisms and pathogens. [1], [3].…”

“…Homogenization, through application of pressure, reduces the milk fat globule size and prevents fat separation from the milk [1]. Homogenization decreases the size of milk fat globules by pumping milk at high pressure through a valve.…”

“…During milk processing, homogenization makes physicochemical changes that affect the characteristics of dairy products and develop their texture and flavor [1]. Homogenization is the mechanical process which reduces the size of the fat globules via pressure and decreases the separation of the creamy part of the product.…”

“…Furthermore, homogenization influences the dairy products especially yogurt. The small fat globules made by HPH tend to incorporate into the milk proteins, casein and denatured whey, during acidification and gel formation [1]. The viability of probiotics bacteria is enhanced by increasing the homogenization pressure (100 to 300 Mpa) due to producing peptides and free amino acids which are necessary for their growth and viability during storage [7], [8].…”