21 热杀菌工艺设计(中英文).ppt

1、商业无菌包装食品热加工设计,Raymond H. Carroll 商业无菌包装食品培训课程,Copyright 2010 马里兰大学 保留所有权,Thermal Process Design for Commercially Sterile Packaged Foods,Raymond H. Carroll Commercially Sterile Packaged Foods Training Program,Copyright 2010 University of Maryland All Rights Reserved,热力杀菌权威,FDA 定义 科学建立低酸罐头或酸化食品的加热过程的个

2、人或组织。这一过程建立在科学的数据之上，包括罐头的加热数据、致病菌及腐败菌的耐酸性、和相关的热穿透数据。这一权威必须包括热力学专业知识、酸化处理要求、足够的经验和相关的设备。,Process Authority,FDA definition The person or organization that scientifically establishes thermal processes for low-acid canned foods or processing requirements for acidified foods. The processes are based on s

3、cientifically obtained data relating to heat or acid resistance of public health and spoilage bacteria and/or upon data pertaining to heat penetration in canned foods. The process authority must have expert scientific knowledge of thermal and/or acidification processing requirements and have adequat

4、e experience and facilities for making such determinations.,热力杀菌权威,USDA 定义 热力杀菌权威指个人或组织具有密封包装食品的热加工要求的专业知识、具有相关的设备、被指定在本部分履行相关职能。,Process Authority,USDA definition a processing authority is the person(s) or organization(s) having expert knowledge of thermal processing requirements for foods in herme

5、tically sealed containers, having access to facilities for making such determinations, and designated by the establishment to perform certain functions as indicated in this subpart.,热加工权威,食品公司有自己的人员 坎贝尔公司目前有四名 大学教授 Kirk Dolan博士, 密歇根州立大学 工业组织 GMA (formerly NFPA) 国家食品实验室 咨询公司 Dover Brook Associates, I

6、nt. Product Safety Consultants 设备 / 容器供应商 FMC, Silgan 容器公司,Process Authority,Food Companies may employ their own Campbells currently has 4 Some University Professors are PAs Kirk Dolan PhD, Michigan State University Industry Organizations GMA (formerly NFPA) National Food Labs Consulting Companies D

7、over Brook Associates, Int. Product Safety Consultants Equipment / Can suppliers FMC, Silgan Containers,热力杀菌权威,FDA / USDA认可的专家 职责: 开发或监督所有热加工过程 检查加工偏离及处理情况 杀菌锅质量的认可 特殊批代码的核准 设定保温及接种装罐要求，检查结果证明产品,PROCESS AUTHORITIES,Expertise recognized by FDA / USDA Responsibilities: Develop / Authorize all thermal

8、processes Review process deviations / disposition Authorize retort qualifications Approve special batch notes Set requirements for incubation / inoculation packs, review results and approve for production,热加工食品,商业无菌包装食品 液态、液固混合 Aw0.85 非冷冻食品 密封包装 无化学防腐剂 不包括: 酒精饮料 发酵食品,Thermally Processed Foods,Commer

9、cially Sterile Packaged Foods Liquid, Liquid-solid mixAw0.85 Non-refrigerated foods Hermetically sealed packaging No chemical preservatives Does not include: Alcoholic beverages Fermented foods,指数递减时间D值,D = 杀死90%细菌数需要的时间 具体到生物体、媒介及温度 微生物数量的减少 Log 递减 10612D process10-6 (.000006),Decimal Reduction Tim

10、e,D = time to reduce population 1 log (90%) Specific to an organism, media, and temperature Populations of microorganisms are reduced Log reductions 10612D process10-6 (.000006),指数递减时间,Decimal Reduction Time,指数递减时间,Decimal Reduction Time,耐热性,Z = D值按十分之一或十倍变化时，所相应的加热温度的变化 Z = (T2 T1) / (Log D2 Log D1

11、),Thermal Resistance,Z = Temperature change resulting in a 1 log or tenfold change in D value Z = (T2 T1) / (Log D2 Log D1),耐热性,Z值的意义 在任何温度下计算D值 D = D0*10(To T) / Z Example D121 = 0.2 分, Z = 10oC 计算 D101 D101 = (0.2)*10(121-101) / 10 = (0.2)*102 = 20 minutes,Thermal Resistance,Significance of Z valu

12、e Allows for calculation of D at any temperature D = D0*10(To T) / Z Example D121 = 0.2 minutes, Z = 10oC Calculate D101 D100 = (0.2)*10(121-101) / 10 = (0.2)*102 = 20 minutes,致死力,F =某温度条件下杀死一定浓度的细菌所需要的时间 F0 =参照温度条件下所需要的时间 F0 = F12110 = minutes at 121oC, Z=10 F0 = F * 10(T-To)/Z example F=10 minutes

13、, T=111oC F0 = 1 minute,Lethality,F = number of minutes at a temperature F0 =Minutes at a reference temperature F0 = F12110 = minutes at 121oC, Z=10 F0 = F * 10(T-To)/Z example F=10 minutes, T=111oC F0 = 1 minute,加热曲线,完整的杀菌曲线:,Temperature,Real Time,Min,121.1C 250F,Fo 0 + 3 + 7 + 2 + 0 = 12 min,0 3 7

14、 2 0,Product Heating Curve,Integrated Sterilization Value:,Temperature,Real Time,Min,121.1C 250F,Fo 0 + 3 + 7 + 2 + 0 = 12 min,0 3 7 2 0,热加工过程的设计,微生物 输入 D Z - Fo,加热 输入热穿透数据,加工 计算,生物验证,Design of Thermal Processes,Microbiological Input D Z - Fo,Heat Penetration Input,Process Calculation,Biological Con

15、firmation,热穿透实验:热电偶,热电偶设计:,Heat Penetration Tests:Thermocouples,Thermocouple Design:,热穿透,热电偶位置: 热电偶插入罐头内部.,数据获取,缓慢加热,Heat Penetration,Thermocouple Placement: Thermocouple installed in a can.,To data acquisition,Slowest heating Spot,热穿透,传递加热时电偶的位置: 容器的几何中心(GC).,传递,Heat Penetration,Position of thermoc

16、ouple for Conduction Heating: Container geometric center (GC).,Conduction,热穿透,对流加热时电偶的位置: 容器底部上方1英寸,对流,Heat Penetration,Position of thermocouple for Convection Heating: About one inch above the bottom (1” AB) of the container.,Convection,热穿透,传递加热与对流加热的标准曲线 (300 x 407 can):,15 30 45,300 200 100 0,Tim

17、e (min),Temperature (oF),对流,传递,Heat Penetration,Standard Plot of Conduction and Convection Heating (300 x 407 can):,15 30 45,300 200 100 0,Time (min),Temperature (oF),Convection,Conduction,热过程计算,计算方法 一般方法 Plot F/t vs. t, or lethality per unit time vs. time F/t = 10(121-T)/Z Calculate area under curv

18、e = Lethality F0 (minutes),Thermal Process Calculation,Calculation methods General Method Plot F/t vs. t, or lethality per unit time vs. time F/t = 10(121-T)/Z Calculate area under curve = Lethality F0 (minutes),热过程计算,计算方法 Ball 公式法 热致死力的作用 加热曲线的斜率 加热结束后终产品温度与介质温度的差异 更灵活 参考热渗透数据可以: 改变初始温度 改变杀菌锅温度 改变致

19、死力 计算新的加工过程,Thermal Process Calculation,Calculation methods Ball Formula Method Lethality of heating is a function of the slope of heating curve difference between final product temperature and heating medium temperature at end of heating More flexible with heat penetration data can: Change IT (init

20、ial temperature) Change retort temperature Change lethality And calculate a new process,热过程计算,计算方法 每一种方法都需要大量的时间去了解 电脑软件可用于计算加工过程 每种方法都需要修正 由热力杀菌权威指导热加工过程的计算,Thermal Process Calculation,Calculation methods Each method requires a significant amount of time to learn Computer programs are available to

21、calculate processes with either method Modifications to the methods are also available Thermal process calculations should be made or directed by a Process Authority,产品加热曲线,00 30 1:00,121 93 38,Time,Temperature (deg C),Heating & Cooling Medium Temp.,Product IT,Start cycle steam on,Retort CUT,Process

22、 time,End of heating: steam off. Cold water on,Cooling water temperature,Retort up to temp. start timing process,Product Heating Curve,00 30 1:00,121 93 38,Time,Temperature (deg C),Heating & Cooling Medium Temp.,Product IT,Start cycle steam on,Retort CUT,Process time,End of heating: steam off. Cold

23、water on,Cooling water temperature,Retort up to temp. start timing process,接种装罐实验,检查计算过程. 商业产品 加入的微生物 不同条件的加工过程 加工条件 亚致死加工条件 确定微生物残留,Inoculated Test Pack,Used to check calculated process. Product prepared commercially Microorganisms added to product Processed under varying conditions Process conditi

24、ons Sub-lethal process conditions Determine microorganism survival,热加工方式,杀菌锅 (封闭容器内杀菌) 静态式杀菌锅 传递加热 自然对流 转动式杀菌锅 强制对流 二者可以 成组 连续,Types of Thermal Processes,Retort (product sterilized in closed container) Static or still Retorts Conduction heating Natural Convection Agitating retorts Forced convection Static and Agitating retorts can be Batch Continuous,热加工方式,加热介质 蒸汽 蒸汽 / 空气 水 全浸没 喷淋 级联,Types of Thermal Processes,Heating Media Steam Steam / Air Water F