| Author | Arparat Huttasan |
| Call Number | AIT Thesis no.FB-07-11 |
| Subject(s) | Rice wines--Thailand
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Food Engineering and Bioprocess Technology, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. FB-07-11 |
| Abstract | Thai rice wine (Sato) was produced from glutinous rice (Kor-Khor 6 variety) with 3 different degree of milling(0%,10% and 15%), and fermented using two kind of starter (Pure microorganism and Loog-Pang (mixed of herbs and steamed rice)). The aim of this study was to use E-nose to discriminate rice wine in different factors such as three degree milling of rice, two types of starters and fermentation time. For rice wine from 10% degree of milling and pure microorganism, it was analyzed at 10, 15, and 20 days to study changing of rice wine quality within three different fermentation times. Three main aroma compounds namely ethyl acetate, ethyl butyrate, and 1 -hexanol were analyzed by GC, E-nose and sensory evaluation. One of them was Ethyl acetate that can indicated contamination of acetobactor in rice wine and Ethyl acetate can be detected by human sensory at above 12 mg/l but it becomes an undesired flavor if it reaches a high concentration. . Microbial test was also conducted to check contamination of acetobactor that was main producer by ethyl acetate. Result revealed that degree of milling of rice, and type of starter affected to quality of rice wine based on aroma compounds. Electronic nose can classify 100% degree of correct classification when applied to Principal Component Analysis (PCA) and Canonical Discriminate Analysis (CDA) plot. Main aroma compounds in rice wine were detected by GC and decreased when increased with degree of milling of rice.Based on different of mechanism of each microorganism contained in Loog-Pang the production of aroma compound in rice wine that had less than using pure microorganism as starter was affected. GC results were also supported differential of rice wine samples which discriminated by electronic nose and showed quantitative and qualitative of compound which E-nose can not showed. Microbial technique was used to advocate the result from GC but the result was not similar. The higher contamination of acetobactor in rice wine using Loog-Pang as starter was low in concentration of ethyl acetate compare to the rice wine using pure microorganism as starter. It might be the pure yeast also can produce ethyl acetate while Loog-Pang may not contain this microorganism. For sensory analysis, the results show less of percent of classification when compare to E-nose. Percent of liking presented the highest at rice wine which made from optimum degree of milling rice at 10% and followed by 0%, and 15%, respectively.The patterns of sensor response from electronic nose were used to predict ethyl acetate values by artificial neuron networks (ANN).The best result was observed by a recurrent networks type III (output layer fed back into input layer) and standard net type I (every layer is connected or linked the immediately layer) with R² (correlative coefficient) between actual and predicted was 0.9912 and 0.9793, respectively. The development of neuron network models can be used for grading quality of rice wine in term of ethyl acetate concentration into five groups for classification less than 100% and three groups for classification of 100%. |
| Year | 2007 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. FB-07-11 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Food Engineering and Bioprocess Technology (FB) |
| Chairperson(s) | Athapol Noomhorm; |
| Examination Committee(s) | Rakshit, Sudip Kumar;Jayasuriya, Hemantha P; |
| Scholarship Donor(s) | RTG Fellowship; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2007 |