Method for preparing concentrated high-protein yogurt before fermentation

A method for preparing concentrated high-protein yogurt, comprising:

• (A)
• heating a high-protein base material at pH of 6.6 to 6.8 and at a temperature of 80° C. to 95° C. for 10 to 30 minutes, wherein the base material has a decalcification rate 32.9% to 44.0%;
• cooling to 40° C. to 45° C.,
• adding 0.05% to 0.2% (w/w) of a starter,
• fermenting at 40° C. to 45° C. until the pH drops to a value of 4.9;
• and
• incubating at 0° C. to 8° C. for 12 to 36 hours to obtain the high-protein yogurt;
• or,
• (B)
• heating the high-protein base material at pH of 6.6 to 6.8 and a temperature of 80° C. to 95° C. for 10 to 30 minutes, wherein the base material comprises a decalcification rate of 32.9%;
• cooling to 40° C. to 45° C.,
• adding 0.05% to 0.2% (w/w) of a starter, and
• fermenting at 40° C. to 45° C. until the pH drops to a value of 5.0;
• and
• incubating at 0° C. to 8° C. for 12 to 36 hours to obtain the high-protein yogurt;
• wherein the starter comprises Lactobacillus bulgaricus and Streptococcus thermophilus, with a viable bacteria count ratio being (2:1) to (1:2);
• wherein protein concentration in the high-protein yogurt obtained by the method is 7 mass % to 15 mass %;
• and
• wherein the high-protein base material is prepared by:
• (a) spray-drying a concentrate of milk protein concentrate (MPC) or micellar casein concentrate (MCC) to obtain MPC or MCC powder,
• (b) redissolving the MPC or MCC powder in skim milk or water until a protein content thereof is 7% to 15%,
• (c) stirring for 20 to 40 minutes,
• (d) homogenizing at 20 mPa to 30 mPa in cycles for 2 to 4 times, and
• (e) performing decalcification treatment to obtain the high-protein base material with the decalcification rate of 32.9% to 44.0%.