Studies On The Processing Technology About Acidic High Protein Dairy Of Fruits

The products of fruits dairy have become one trend of dairy industry. In our country, the productions of these dairy products still were in beginning as some problems. The stability is one of the most prominent problems, which can be solved through adding stabilizers and improving technology. The facts of influencing stability and esthetic quality of the products have been studied in this paper. The main results were summarized as follows:1. The additions of orange juice and organ acid had destroied the stability of milk and the protein had been precipitated.2. The stabilizers and emulsions can help to improve the stability of products; the optimum using rate of CMC-Na and PGA was 3:4 in orde to restrict the precipitation of milk; and considering the negative effect of CMC-Na to the sense of mouthful of products, the optimum rate of CMC-Na and PGA should be 2:3. There was not linear relationship between the stability of products and the increase of stabilizer. 0.02% of sucrose esters of fatty acids and 0.06% of distilled monoglycoride have effect to restrict the separation of products.3. The technology has distinct influence on the stability of milk of orange juice. The pasteurization of milk should use ultrahigh temperature (UHT); the orange and acid shoud been added after the mixtures had been cooled to 30 癈 so to avoid the coacervation of proteins. The raw milk shoud be homogenized so to improve quality of product and avoid separation of milk fat and the mixtures did not be homogenized, which no effect to improve the stability of product.4. The optimum formula of milk of orange juice has been screened through the second orthogonal rotating experiment design. The optimum formula was as follow: 11.5% of orange juice; 0.17% organ acid;3% of white sugar; 0.17% of stabilizer(CMC-Na:PGA=2:3); 0.24% of phosphate(sodium polyphosphate: sodium pyrophosphate = 1:1); 0.02% of sucrose esters of fatty acids, 0.06% of distilled monoglycoride; 76.42% of milk; 8% of wate; 0.64% of skim milk powder.5. The foundation of production of stirred orange juice-yoghurt is the processing of set yoghurt. The optimum formula of stirred orange juice-yoghurt was as follow: 60% of milk; 1.6% of skim milk power;8% of white sugar; 12% of orange juice; 18% of water; 0.3% of CMC-Na; 0.1% of PGA; and the optimum processing was as follow: the raw milk was pasteurized under 90 for 7min; the raw milk was homogenized under 30 , 10Mpa ;and incubated under 38 for 4.5h.6. The yoghurt beverage of orange juice-tianjiuniang and the stirred strawberry yoghurt was researched under the works of abover. The result showed: the optimum formula of the yoghurt beverage of orange-tianjiuniang was as follow: 0.375% of CMC-Na; 0.125% of PGA; 55% of milk;6.15% of white sugar ; 15.28% of water; 15.28% of tianjiuniang and 7.69% orange juice. The set yoghurt was produced and then the yoghurt beverage of orange-tianjiuniang was produced through adding stabilizers (stabilizers, water and white sugar) and homogenizing the mixture under lOMpa.The optimum formul of the stirred strawberry yoghurt was 4%(CMC-Na: PGA=3:1) of stabilizers and 20-25% of strawberry.