Development Of Infant Formula Milk With Hydrolyzing Cow Milk Protein By Exogenous Enzyme

Human milk is the natural ideal food for infants. In special case, cow milk seems to be the best alternative food for infants because it is affluent in nutrient. There are some important differences of protein construction between human milk and cow milk. Cow milk protein is not easily digested and absorbed. Part of infants are sensitive to it. The proportion of casein and whey in the current infant formula is adjusted through adding a large of desalted whey powder. But the indigestible and irritable constitutions are still active. Hydrolyzing the cow milk protein by protease can improve its digestibility of casein and the irritability of casein and P-lactoglobulrn. The hydrolysate was used for raw material to produce the infant formula milk.The market research often infant formula powders had been made. The protein contents of all infant formula powders are accorded with their label. They are between 11% and 14%, reach GB10766-1997.The whey contents are from 33% to 35%, less than 60%, far from GB10766-1997. Their amino acid component and content are nearly equal to human milk. Only Cys is evidently less than human milk. Met is a little more. The grosses of Cys and Met are approach to human milk.Taking the hydrolysis degree, state, color and bitter extent as assessing indexes, the experiment had screened hydrolysis enzyme from Trypsin, Alcalase. Neutrase. A.S.1.398 and papain. Trypsin was be chosen as the target enzyme because it has the strongest ability to hydrolyze cow milk protein and give its hydrolysate the best sensory score.The optimum hydrolysis temperature, enzyme dosage and hydrolysis time were determined by single factor design. The hydrolysis degree of cow milk protein could reach 4% on the conditions of temperature of 40 C, enzyme dosage of 1200-1400u/g protein and time of 40~50 minutes.The cow milk hydrolysate by Trypsin tasted bitter. The bitterness of hydrolysate was obviously reduced by heating, but not completely eliminated. 0.8% of 1-cyclodextrin was used as the screening agent to effectively embed bitterness.The infant formula milk was produced by mixing the modified cow milk, lactose, vegetable oil and b-cyclodextrin, fortified with DHA, AA, nucleotide, taurine and L-camitine. The mixture was homogenized under the press of 20Mpa and canned.In the optimum formula: there are 1.65% of protein, 3.46% of fat and 7.4% of carbohydrate. The proportion of unsaturated fatty acid and saturated fatty acid is 1.499. 46.24% of quantity of heat was provided by fat and 90.5% of carbohydrate was provided bylactose. The linoleic acid content was 0.93g/100mL.The amino acid analysis of infant formula milk had been operated. In addition to Cys. the content of other amino acids are higher or a little higher than that of human milk. Amino acid model was nearly equal to that of human milk. So it was easily digested for infants.The sensory value of infant formula milk showed that it had the pure aroma of cow milk and light vegetable oil smell, ivory-white, equal texture, without clot and deposition. The microbiological examination was up to grade.Postgraduate: Chen Hui Major: Food Science Supervisor: Prof. Huo Guicheng...