A Formula Developed For Imitation Human For Preterm And Its Asorption Assessment

Human milk is the natural ideal food for infants. Human milk is also regarded as the most ideal food for preterm infants. As breast milk substitutes, product from cow milk seems to be the best alternative food for infant. Cow milk is rich in nutrients, but there are some important differences of protein construction between human milk and cow milk. Cow milk protein is not easily digested and absorbed. Parts of the premature infants are sensitive to it. The proportion of casein and whey in most of the current infant formula is adjusted through adding a large of desalted whey powder. But the indigestible and irritable constitutions are still active, and not simulation breast milk in real sense. The digestibility and nutrient of the fat are different because of the form of the fatty acid. Owing to the different fatty acid sort, the milk fat is digested and assimilated much harder than the breast milk. As the level of the unsaturated fatty acid of the preterm breast milk is higher than cow milk, the digestibility of the breast milk is higher about 20%. The preterm infants have higher demand of lactose than infants, but they are lack of lactose enzyme internal due to short of adequate palace growth time, making hydrolysis of lactose become a hard problem.In the subject, no matter accorded with protein requirements for preterm infant and the proportion of casein and whey, but also realized the amino acid modal humanization, achieving breastfeeding of amino acid really. Cream, soybean oil, coconut oil and sunflower oil were formulated for imitating fatty acids of mother's dairy according to the structure of fatty acids in breast milk for preterm, using MATLAB established mathematical model, making content of fat in preterm formula and fatty acid as like as the breast milk, to improve digestibility of fat. Adding lactose enzyme improved the problem of digestion, reseaching hydrolysis conditions of lactose enzyme, and effect of hydrolysis in the animal body. The experiment and conclusions were obtained as follows:1) Using GC-MS analyzed structure of fatty acid in cream and 7 kinds of vegetable oil, soybean oil, coconut oil, sunflower oil and cream were formulated according to the content of palmitic acid (C16:0), oleic acid (C18:1), linoleic acid (C18:2), MCT (C 12:0) in breast milk for preterm, through MATLAB software calculated extent of adding:sunflower oil 30%-40%, soybean oil 10%-20%, coconut oil 10%-20%, cream 30%-40%. Using D-optimal in Design Expert 7.1.3 designed experiment, the best proportion of mix oils was confirmed:sunflower oil 35%, soybean oil 15%, coconut oil 17%, cream 33%, and obtained digestibility influence of four kinds oil. The theoretical value of fat digestion was 75.38%.2) The single factor experiment and the perpendicular experiment were used to ascertain the optimum hydrolysis conditions of lactose enzyme:additives 90 U/g, temperature 40℃, hydrolysis time 3h, pH 6.5. In these conditions, the hydrolysis degree was 50.43%.3) All amino acids were satisfied according to the amino acid modal of humanization, the digestibility of formula of amino acid breastfeeding was significantly improved by in vitro mimic digestion, the digestion was about 82%.4) The 3 groups of animals digest experiment were used to evaluate the digestibility of fat, protein and lactose. The result showed that the digestibility of preterm formula of our experiment was significantly better than infant formula from local market and control group in the 3 forms (p<0.05). The digestibility of fat was 76.33%(4h), was much close to the theoretical value. The digestibility of protein was 80.65%(4h), was extraordinary similar to vitro mimic digestion. The hydrolysis degree of lactose was 92.52%(4h), significantly improved.Innovate points:1) Using MATLAB software established mathematical model and D-optimal designed experiment, the proportion of mix oils were determined, according to the structure of fatty acids in breast milk for preterm.2) The optimum hydrolysis conditions of lactose enzyme in preterm formula was ascertained.