Study on developing a high quality chinese paocai by inoculated compound lactic acid bacteria

• Main Author: 吳宜臻
• Other Authors: 李益榮
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/54976218220565283083

碩士 === 國立嘉義大學 === 食品科學系研究所 === 99 === This study aimed to develop a fermented cabbage paocai with low nitrite content. Experiments were divided into five stages: First, find the optimal brine salting conditions, the optimal innoculum and the optimal amount of spices added. Second, to proceed compound lactic acid bacteria fermentation test. In this test, there are three kinds of lactic acid bacteria being used, listed as the following: Lactobacillus acidophilus CCRC 14079、Leuconostoc mesenteroides subsp. CCRC 12580 and Lactobacillus plantarum subsp. CCRC 10069. And the test also operated with different ginger content and salinity of pickle solution. The paocai in this test took three days fermented under 15℃. After the paocai preparation, an analysis of its pH, titratable acidity, textural properties, turbidity, nitrite content and sensory evaluation, which serving as the quality of paocai, was carried out. Then, the quality attributes of paocai were used as criteria to find the optimal formulation for compound lactic acid bacteria used in cabbage paocai preparation. The third stage was to compare physical and chemical properties of paocai naturally fermented, optimal compound bacteria fermented paocai and commercial paocai collected from local market. The fourth stage was to find the optimal formulation for seasoning test of optimal compound bacteria of paocai. Finally, to compare total lactic acid bacteria count of different sources of paocai to explore the degree of fermentation the paocai collected from local market or fermented in lab. The results showed that the optinum condition of brine salted cabbage preparation was saline concentration (9 %), ratio of cabbage to saline (1:8), and brine salting time (5 hr), respectively. The dehydration rate of cabbage was 22.35 % under this condition. Then the optinum amount of lactic acid bacteria inoculation was 20 % (v/w) that of dehydrated cabbage. And then, the addition volume of ginger was set from 0 to 12 %. The optimum formulation of compound lactic acid bacteria fermented test was: when Lactobacillus acidophilus CCRC 14079 was 58.3 %, and Leuconostoc mesenteroides subsp. CCRC 12580 was 41.7 %. Ginger adding proportion was 9.42 %, and salinity of pickle solution was 0.56 % . The pH of paocai fermented under this condition was 3.95, titratable acidity was 0.28 g/100 mL, crispiness was 21.61g, tubidity of pickle solution was 243.83 NTU, and the content of nitrite was 1.995 ppm. Sensory score of fragrancy and overall preference was 6 and 5.86 under a nine point hedonic scale, respectively. There was no significant differences found between properties of fermented cabbage paocai prepared in confirm test and that of theoretical result, except the crispiness of paocai. Comparison of chemophysical properties of various paocai showed that the nitrite content of naturally fermented paocai was 2.21 times more than optimal compound bacteria-fermented paocai. The nitrite content of commercial paocai collected from local market was lower because of its relatively lower degree of fermentation. On the part of texture, optimal compound bacteria of paocai had greatest performance, and significantly better than paocai collected from local market. The result of seasoning test suggested that, while sugar and vinegar was added into pickle solution, optimum addition amount of sugar and vinegar was 110 mg/mL and 75 μL/mL, respectively. And there were no significant differences found between sensory preference of seasoned paocai and paocai collected from local market. Total count of lactic acid bacteria of optimal compound bacteria-fermented paocai was found more than 108 cfu/g, and that of the seasoning-treated paocai decreased in a log value, nevertheless, paocai collected from local market had only 104~105 cfu/g of total lactic acid bacteria count. These result showed that optimal compound bacteria-fermented paocai in this study has potential to develop into commercial products.