03682nas|a2200241 a 450000500170000000800410001703500150005810000260007324500710009926000670017030000220023749000270025950001520028650200570043852026210049565000120311670000390312870000450316770000470321271000570325981000590331685600650337520260817162802.0071022s2006    th uu|m rtt   0|  a1eng d  a.b118329880 aAtcharaporn Khoomtong10aAntioxidant fortification of soya milk using extracted isoflavones  aPathum Thani, Thailand :bAsian Institute of Technology,c2006  a80 leaves :bill.1 aThesis ;vno. FB-06-06  aA thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development  aThesis (M.Sc.) - Asian Institute of Technology, 2006  aThe objective of this work was fortification of soy milk with the products extracted from soya. Whole grain Non-GM and GM soybeans were investigated for optimization of isoflavones extraction using non-toxic solvent ethanol and their antioxidant, antibacterial activities. Sensory evaluation of this product of fresh soymilk fortification with isoflavone stored with shelf life of 15 days was also studied.  The best concentration of ethanol solvent (a food grade solvent) for extraction of isoflavone from Non-GM and GM soybean at a level of 40°'0. A photodiode array detector High-Performance Liquid Chromatography (HPLC) was used for analysis. Antioxidant activity of isoflavones extracted was measured using 2,2-Diphenyl-l-picryl-hydrazyl (DPPH) free radical method. The antioxidant property of isoflavone was very good. The highest and lowest activity of isoflavone extracted from Non-GM soybeans was 98.62±0.127°.'0 and 94.11°'0, respectively. The antioxidant activity from isoflavone extracted of GM soybeans was 92% and did not show significant (p>0.05) change with concentration of isoflavone in the range tested.  The isoflavone extracted from both of soybean, Non-GM and GM soybean were found to be the most effective antibacterial fraction for both of Gram positive bacteria, Bacillus subtilis and Bacillus cereus and Gram negative bacteria, E culi.  Sensory evaluation showed significant (p<0.05) differences between the different concentration of isoflavone extracted from Non-GM soybean fortified in Non- GM soymilk and isoflavone extracted from GM soybean fortified in GM soymilk. Non-GM soymilk samples were more preferred than the GM soymilk samples. However as they were not the same variety the difference may not necessarily be due to genetic modification. The difference might he became of difference in variety. On the basis of DPPH radical scavenging activites, the DPPH radical scavenging activites of isoflavones slightly decreased in soymilk after fortification to different level.  Soymilk fortified with 1.00 %w/v isoflavone extracted, from both Non-GM and GM showed low value of total plate count during storage. This shows that w1th high concentration of IF extension of shelf life of soymilk is possible. The isoflavone extracted from both of soybean, Non-GM and GM soybean when for used fortification of soymilk were found not to inhibit eflectives both of Gram positive bacteria, Bacillus subtilis and Bacillus cereus and the Gram negative bacteria, F. cull. This might be due to loss of isoflavone after processing from soybean to soymilk or due to the low concentrations used. 0aSoymilk1 aRakshit, Sudip Kumar,eChairperson0 aAthapol Noomhorm,eExamination Committee1 aJayasuriya, H.P.W.,eExamination Committee2 aRoyal Thai Government Fellowship,eScholarship Donor2 aAsian Institute of Technology.tThesis ;vno. FB-06-06  3Full-Textuhttp://203.159.5.9/ait-thesis/detail.php?q=B09868