Development And Pilot Design Of Hypoallergenic Whey Protein Product

Milk is one of the eight categories of foods causing food allergies.However,it's also the main protein source especially for infants.It was reported that 8%of young children and 2%of adults were allergic to cow milk.At present,enzymatic hydrolysis is the main way to produce the hypoallergenic dairy product,which has many advantages such as mild conditions,simple process,mature technology,strong feasibility.Whey protein in is the essential raw material for infant formula.Therefore,study on hypoallergenic whey protein can ensure allergic people to consume safely but also develop key technology for hypoallergenic products.The present research was composed of four parts including establishment of hydrolyzing whey protein by protease,identification and allergenicity evualtion of hydrolyzate from whey and pilot scale experiments of hydrolyzed whey protein powder.The main research results and conclusions are described as follows.1.Four kinds of commonly used proteases in laboratory were selected by using the single factor experiment.Among them,the best one was alcalase and optimum conditions was evaluated by method of Response surface with parameters of 51.27?,7.16%(E/S),pH9.30 and 5.67h.2.The molecular weight of whey protein hydrolyzate was detected by both of Tricine-SDS-PAGE and High Performance Size Exclusion Chromatography.Moreover,Ability binding changes of IgG/IgE to hydrolyzed whey protein by using indirect competitive ELISA.Finally,residual allergenic epitopes from whey were identified by using HPLC-MS/MS.The results were shown that the molecular weight of hydrolysate was less than 5kDa and the antigenic aliblity decreased to the lowert level when the time last for 5.67h as well as the IgE ability.In addition,the binding ability of IgG/IgE to a-lactalbumin reduced to 1/500 compared with intact allergen,while binding ability of IgG/IgE to ?-lactoglobulin decreased to 1/787.5 and 1/983,respectively.Meanwhile,10 allergenic epitopes still existed in tht hydrolysate which were AA13?26,AA93?102,AA47?58 in a-La and AA1?16,AA21?40,AA41?60,AA85?96,AA139?156,AA72?86,AA92?106 in p-Lg.3.Allergenicity of hydrolyzed whey was assessed by using animal model and the results showed that the levels of specific IgGi and IgE in the serum,histamine level of plasma,and the levels of IL-4,IL-5 and IL-13 secreted from spleen cell of are significantly reduced in experiment group compared with the control group.All data indicated that the allergenicity of hydrolyzed whey has decreaed after hydrolyzing.4 Pilot process for producing hydrolyzed whey were designed and 300 g of whey protein was hydrolyzed according to the techinique procedure.The content of protein and amino acid of hydrolyzed whey were detected by the Kjeldahl apparatus and amino acid analyzer withwhey is 63.1%and(62.1 + 4.4)g/100g which were In addition,by comparison with formula milk,the results showed that molecular weight of the hydrolyzed whey was below 5kDa and the indirect competitive ELISA indicated that the antigenicity of the hydrolyzed whey was similar with commercial partially hydrolyzed formula milk.