Transcript 第三部份 - 東吳微生物學系

第三部份：食品保存與微生物
其他保存方法
Other Preservation Methods
黃顯宗
東吳大學
M202
教學目標
認識其他食品保存方法與微生物之關係
認識發展中的食品保存方法與微生物之關
係
ASEPSIS
避免微生物污染
食物的天然阻隔
 如 組織、表皮、硬殼等
加工的無菌操作
包裝處理
Removal of Microorganisms
Filtration
juice, soft drink, beer, wine, water
Centrifugation
Sedimentation
Washing
High Pressure Processing
Shape, color, and nutrients of most foods
are not affected.
Commercially available in Japan since the
early 1990s.
Reference
Change in inactivation of
Zygosaccharomyces bailii with pressure
http://www.wsu.edu/~gmhyde/433_web_pages/433Thermal-nontherm-procesg/HighHydroPressure.html
MPa
1
Psi
145
kg/cm2
10.19
kg/in2
101945.15
1個標準大氣壓等於101,325 Pa
0.101325 MPa
Control of Listeria in meat by
D value又出現了
high pressure
http://www.amif.org/AMIFResearch/1AMIpressure.pdf#search='High%20Pressure%20listeria'
Response of Bacteria
Mutants resistant to high pressure were
found
Stress response system stimulated
Pulsed Electric Fields, PEF
短暫高電壓的處理
G＋較 G- 耐性強，更不容易殺死
孢子比營養細胞耐性強
Stationary phase比 log phase 耐性強
傷害細胞膜致細胞死亡
與電的強度、處理時間、處理溫度有關
Electrolyzed Oxidizing Water
 是利用稀鹽水加以電解，在陽極產生具pH值
在2～6之間、氧化還原電位 (oxidation
reduction potential, ORP) 為 +1,000 mV以上，
含有效氯並具有殺菌特性之酸性電解水
 酸性電解水，具有殺菌能力
Electrolyzed water
http://www.ewatersystems.com.au/e-water/electrolyzedwater/how-does-it-work/
電解水處理 Listeria 菌
Liu and Su, 2006
處理 E. coli, Salmonella和
Listeria 菌
Venkitanarayanan et al., 1999
Manothermosonication
或稱為Thermoultrasonication
同時結合熱與超音波處理
Effective in reducing the thermal
resistance of enzymes peroxidase,
lipoxygenase and polyphenol oxidase.
Alternative Food Processing
Technologies
Pulsed Light, Oscillating Magnetic Fields,
Ultrasound, X-ray….
FDA
http://vm.cfsan.fda.gov/%7Ecomm/ifttoc.html
PEF處理Listeria菌
Inactivation kinetics of L. innocua
NCTC 11289 at different electric
field strengths. Symbols: ■, 2.0
to 2.1 V/μm; , 2.3 to 2.5 V/μm;
●, 2.7 to 3.0 V/μm; , 3.2 to 3.5
V/μm; ■, 3.6 to 3.9 V/μm. The
pH of the treatment medium was
5, the conductivity was 0.51 S/m
at an inlet temperature of 40°C,
and the pulse length was 3.9 μs.
The inoculum contained 1.4 × 106
CFU/ml. The results are the
means of data from two
experiments, and standard
deviations are indicated by error
bars.
Wouters et al., 1999
使用Phages
如針對Listeria, E. coli, Salmonella等
參考文獻
Bacteriocins
 細菌形成，如乳酸菌
 Protein性質, destroyed by digestive enzymes
 Nontoxic
 Heat stable, storage stability
 No off-flavors or off-odors
 Narrow spectrum of antimicrobial activity
 舉例
 Nisin
 Subtilin, against G+ bacteria, like Nisin
 菌種改良
Bacteriocins-Nisin
http://ans-bv.nl/Admin/mkstats/usage_200310.html
Bacteriocins
Nisin
Subtilin
Natamycin
Tetracyclines