1、食品品质评价,课程编号10142,课程简介,学分：1.5 学时：36 理论：24 试验：12 本课程包含以下几个方面内容 食品品质评价相关理论、方法和在食品生产、开发中的应用。,课程性质,专业选修课 食品科学类课程的解释、分析和例证； 食品加工类课程的有力补充； 意义 课程对学生知识体系构成的完整性具有重要的意义； 为即将工作的学生提供行业专有技术教育； 为从事研究的学生提供深入学习方向的指导。,内容,食品品质评价简介 食品品质评价理论基础 食品品质评价方法 食品品质评价在食品生产和开发中的应用,学习本门课程所需基础知识,食品科学原理 食品工艺学 食品感官评价有无参加认证培训经历,参考书,Au
2、tomation for Food Engineering Food Quality Quantization and Process Control Handbook of indices of food quality and authenticity针对不同产品有质量评价指标 Instrumentation and sensors for the food industry Rapid and on-line instrumentation for food quality assurance有具体质量检测方法 Rheological Methods in Food Process En
3、gineering有例 Rheology Essentials of Cosmetic and Food Emulsions关注乳化，有例子，对研究方法很关注 Rheology of Fluid and Semisolid Foods Principles and Applications重理论，有方法，还有谈到对感官评价的影响 Woodhead,.Stability and Shelf-Life of Food有案例，有感官评价的应用,1. 食品品质评价简介,食品品质评价含义 主要内容 食品品质评价主要指标,食品品质评价的含义,食品是多种成分组成的复杂体系，具有多种特征，这些特征共同构成了食
4、品的品质。 变现为色、香、味、形和质地等等。 食品品质评价：依据科学系统的方法，对食品外在和内在的特征进行检验分析，并与特定的标准进行比较，作出评价。,食品品质评价考察内容分类,卫生 基于外源、内源污染物的有无和多少对产品的安全性进行评价； 营养 基于基本营养素的种类、多少及配比模式对产品利用的有效性进行评价； 质构 基于产品的流变学特征，利用人体的感觉器官或仪器进行测定，综合分析，评价。,食品品质评价主要指标,卫生 微生物：类菌落总数、大肠菌群，其它致病菌检测； 有毒化学物类：有毒重金属、农药、兽药，有毒添加剂； 杂质类：异物,食品品质评价主要指标,营养 营养素：蛋白质、脂肪和碳水化合物等
5、营养成分平衡性：氨基酸模式，蛋白质利用率等等,食品品质评价主要指标,质构 内在：粘弹性、硬度等等 质地、风味 外在：颜色、透明度等等 新技术及相关问题 机器视觉技术、电子鼻技术和电子舌技术 传感器的灵敏度和选择性、合适的数据分析方法、如何建立起完整的检测数据库,关键问题,标准方法 量化 系统分析,1.1 食品品质:食品工业主要关注点,食品质量对于食品工业和消费者同样重要 消费者的需要：安全、卫生和优质 高质量的产品可以确保在整个链中的任何一个部分都获得利益，保证企业的收益。但产品的任何问题可能导致产品的返回、投诉甚至法律纠纷。产生问题的原因可能是多方面的，包括包装、变味、臭味 、腐败、变色、包
6、装不完整、过期和致病等等。 食品工业必须生产品质复合要求并一致的产品，才能保证产品的竞争力和在市场上获利。,1.2 食品品质评价的两类方法,主观方法 基于人的主观判断。需要评价员对研究目标产品参照定性、定量值给出观点。通常是包含感官（质构、风味、气味、颜色和触觉）方法。 随经训练，但仍存在不稳定的现象。,1.2 食品品质评价的两类方法,客观方法 基于不含人评价观点的观察（科学测试）。 食品品质评价的结果与种植者、加工者和消费者的利益紧密相连，并可用于质量控制。 因此需要客观方法，保证结果一致并耗费低。 可分为两类 物理方法，测定大小、质构、颜色、稠度和不完整性等。 化学方法，测定酶、水分、纤维
7、、pH和酸度等。与营养价值和质量等级相关。 客观方法的优点和适用性 一旦方法建立，不受身体状况和心理因素影响，结果一致性良好； 便于自动化，在工业上具有重要意义,1.3 食品品质量化,量化：信息以数字形式表示 优点：便于自动化 在必要的条件下，量化的性能（有效性、代表性）可以通过与感官、分类或机械和化学特性的测定比较来校正。,图1.1,1.3 食品品质量化,食品品质量化的过程 （1）取样 需预先制定计划，采样量需充分，可能需要相关处理。 （2）数据获取 采集、记录数据并存储以备后续分析 （3）数据处理和分析 关系分析 （4）建立模型 利用输入输出数据建立模型 （5）分类及预测 利用模型对样本进
8、行分类和预测感官、机械和化学特性。验证方法。,1.4 食品质量评价的典型案例问题（自动化评定）,产品变异带来的问题（牛肉） 基因、品种等带来的分割、分类问题 气味的测定（电子鼻） 人体难以适应强度和种类问题 连续油炸食品品质评价（自动控制过程难度大） 产品生产过程的复杂性及产品质量一致性的要求。需要控制水分、油含量和油炸程度等等。过程自动化问题、传热、传质和产品质地问题都需要关注。 工程参数如油入口、出口温度、油流速、入口出口水分，油含量。,部分有关品质、质量的术语,Food handler Any person who directly handles packaged or unpacka
9、ged food, food equipment and utensils, or food contact surfaces and is therefore expected to comply with food hygiene requirements (Codex Alimentarius, 1997). Food hygiene All conditions and measures necessary to ensure the safety and suitability of food at all stages of the food chain (Codex Alimen
10、tarius, 1997). Food safety The assurance that food will not cause harm to the consumer when it is prepared and/or eaten according to its intended use (Codex Alimentarius, 1997). Food suitability Assurance that food is acceptable for human consumption according to its intended use (Codex Alimentarius
11、, 1997).,Grade Category or rank given to different quality requirements for products, processes, or systems having the same functional use (ISO 9000:2000). Hazard A biological, chemical, or physical agent in, or condition of, food with the potential to cause an adverse health effect (Codex Alimentar
12、ius, 1997). A biological, chemical, or physical agent that is reasonably likely to cause illness or injury in the absence of its control (NACMCF, 1997). Hazard analysis The process of collecting and evaluating information on hazards and conditions leading to their presence to decide which are signif
13、icant for food safety and, therefore, should be addressed in the HACCP plan (Codex Alimentarius, 1997). The process of collecting and evaluating information on hazards associated with the food under consideration to decide which are significant and must be addressed in the HACCP plan (NACMCF, 1997).
14、,Hazard analysis critical control point (HACCP) A system that identifies, evaluates, and controls hazards that are significant for food safety (Codex Alimentarius, 1997). A systematic approach to the identification, evaluation, and control of food safety hazards (NACMCF, 1997). HACCP, which is recog
15、nized for its science-based approach, consists of a set of seven principles that have been adopted internationally through the work of the Codex Alimentarius Commission. HACCP plan A document prepared in accordance with the principles of HACCP to ensure control of hazards that are significant for fo
16、od safety in the segment of the food chain under consideration (Codex Alimentarius, 1977). The written document that is based on the principles of HACCP and that delineates the procedures to be followed (NACMCF, 1997).,An HACCP plan is obtained after an HACCP team has carried out the activities requ
17、ired by the seven principles of HACCP. HACCP system The result of the implementation of the HACCP plan (NACMCF, 1997). HACCP team The group of people responsible for developing, implementing, and maintaining the HACCP system (NACMCF, 1997). Histogram A bar chart representing a frequency distribution
18、 of a process variable or product characteristic (ASQ, 1998). A graphic summary of variation in a set of data. It is one of seven tools of quality (QP, 2002). ISO 9000 family of standards A coherent set of four quality management system standards facilitating mutual understanding in national and int
19、ernational trade (ISO 9000:2000).,The standards have been developed by the International Organization for Standardization to assist all types and sizes of organizations to implement and operate effective quality management systems. ISO 9000:2000 Quality management systems Fundamentals and vocabulary
20、 describes fundamentals of quality management systems and specifies and defines the terminology used in these systems. ISO 9001:2000 Quality management systems Requirements specify the requirements for the quality management system of an organization that needs to demonstrate its ability to provide
21、products that meet customer and regulatory requirements, and aims to enhance customer satisfaction. ISO 9004:2000 Quality management systems Guidelines for performance improvements provides guidelines that address the effectiveness and efficiency of quality management systems to improve organization
22、al performance and the satisfaction of customers and other parties. ISO 19011:2002 provides guidance on auditing quality management systems and environmental management systems.,Project Unique process consisting of a set of coordinated and controlled activities with start and finish dates, undertake
23、n to achieve an objective conforming to specific requirements including the constraints of time, cost and resources (ISO 9000:2000). Qualification process Process to demonstrate the ability to fulfil specified requirements (ISO 9000:2000). Quality Degree to which a set of inherent characteristics fu
24、lfils requirements (ISO 9000:2000). The totality of characteristics of a product or service that bear on its ability to satisfy stated and implied needs (ASQ, 1998). Quality assurance (QA) Part of quality management focused on providing confidence that quality requirements will be fulfilled (ISO 900
25、0:2000). All those planned or systematic actions necessary to provide adequate confidence that a product or service will satisfy given needs (ASQ, 1998). All the planned and systematic activities implemented within a quality system that can be demonstrated to provide confidence a product or service
26、will fulfill requirements for quality (QP, 2002). See also: quality control.,Quality audit See: audit. Quality characteristic Inherent characteristic of a product, process or system related to a requirement (ISO 9000:2000). See also: characteristic. Quality control (QC) Part of quality management fo
27、cused on fulfilling quality requirements (ISO 9000:2000). The operational techniques and activities that sustain a quality of product or service that will satisfy given needs; also the use of such techniques and activities. (ASQ, 1998) The operational techniques and activities used to fulfill requir
28、ements for quality (QP, 2002). See also: quality assurance. Quality improvement Part of quality management focused on increasing the ability to fulfill quality requirements (ISO 9000:2000). See also: continual improvement. Quality management Coordinated activities to direct and control an organizati
29、on with regard to quality (ISO 9000:2000).The totality of functions involved in the determination and achievement of quality (ASQ, 1998). See also: total quality management.,Quality management system Management system to direct and control an organization with regard to quality (ISO 9000:2000). A fo
30、rmalized system that documents the structure, responsibilities and procedures required to achieve effective quality management (QP, 2002). Quality manual Document specifying the quality management system of an organization (ISO 9000:2000). Quality objective Something sought, or aimed for, related to
31、 quality (ISO 9000:2000). Quality plan Document specifying which procedures and associated resources shall be applied by whom and when to a specific project, product, process, or contract (ISO 9000:2000) A document or set of documents that describe the standards, quality practices, resources and pro
32、cesses pertinent to a specific product, service or project (QP, 2002). Quality planning Part of quality management focused on setting quality objectives and specifying necessary operational processes and related resources to fulfill the quality objectives (ISO 9000:2000). Quality policy Overall inte
33、ntions and direction of an organization related to quality as formally expressed by top management (ISO 9000:2000). An organizations general statement of its beliefs about quality, how quality will come about, and what is expected to result (QP, 2002).,1.5 食品品质和食品安全的区别,食品品质（质量）相关食品特征满足所有已建立要求的程度 食品安
34、全是有关于可能对人体健康产生危害，致病或伤害的特征或特性要求的满足程度 某些食品质量特征如菌落总数也可作为食品安全的指示，但却不是食品安全的特定指标。 对二者作出区别，目的在于强调某些问题对于安全的重要性。 不符合食品安全需要，必定不符合食品品质（质量）需要；复合食品安全需要，不一定符合其它食品质量要求。 食品工业中，食品安全的原理和实践已经集成到食品质量保证或质量控制中，或者存在于质量管理系统。管理程序同时关注食品质量和食品安全。,1.6 食品品质特征（不含安全特征）,相关标准的一致性 (例如标准化的食品) 总量或净含量 (重量或体积) 成分含量 外观（大小、形状、颜色） 风味 香味 质地
35、黏度 货架期稳定性 作为食品的适用性 有益健康的 掺杂 包装 标签,某些特征包含在食品法规中，不符合一致性、质量、成分和标签声明，被认为是“误说”、“误标”或“欺诈” 。 食品酸败、恶化或分解被认为不符合适用性或有益健康的标准。不会产生问题的外源物质通常也被认为不符合标准。 消费者根据自身的需要同样建立质量标准。,1.7 食品品质系统和程序,像其它工业一样，食品工业使用基本的质量控制程序，更复杂的质量保证程序和质量管理系统。 为满足食品质量，某些食品公司使用ISO 9000 质量管理系统标准。这些程序和系统可能包括食品安全的部分。 例如，GMPs and the HACCP system 可以
36、集成到食品工业、质量管理系统或用于检查、监测原料、产品，成为食品质量控制程序的一部分。,基于T_T_T理论检测冷冻冷藏食品品质的方法.pdf,Unavailable,Production Practices and Quality Assessment of Food Crops. Vol. 3, Quality Handling and Evaluation Auditing in the Food Industry: From Safety and Quality to Environmental and Other Audits Quality in the Peoples Republ
37、ic of China Classroom Assessment: Enhancing the Quality of Teacher Decision Making Total Quality Management Choosing a Quality Control System Statistical Methods for Quality Improvement Total Quality Management in Education Production Practices and Quality Assessment of Food Crops. Vol. 4, Proharves
38、t Treatment and Technology Fruit and Vegetable Processing: Improving Quality,DOE: Response Surface Methods,响应面方法Response surface methods (RSM)是决策相关的主要研究分析方法 (1)对工程化系统输入输出关系作出相对精确地预测 (2)对设计的系统进行调整、优化,品质评价举例,http:/ 我国小麦品种有了品质评价系统 中国农业科学院作物科学研究所与首都师范大学生命科学学院合作完成的“中国小麦品种品质评价体系建立与分子改良技术研究”成果，针对我国食品质量急待提高
39、的实际需要，采用常规方法与分子技术相结合，深入系统研究中国小麦品种的品质评价体系和改良方法。它从食品性状指标蛋白质DNA4个层次研究我国小麦品种品质评价体系，其中20个指标（占42）在中国小麦中最早报道。着重建立了中国面条和北方馒头的标准化实验室制作与评价方法，提出并验证面条小麦的选种指标和分子标记选择体系，国内外尚未见到类似报道。改进面包评价方法，明确饼干小麦的选种指标。这一工作为进一步系统改良中国小麦品质提供了评价体系和理论依据。,品质评价举例,http:/.tw/ec/ecjnlarticleView.aspx?atliid=610136&issueiid=42417&jnliid=1508 采用物性测试仪通过对果酱、酸奶、蜂蜜等粘稠状样品的粘稠度的测量，仪器探头的选择，测试方法参数的比较，建立粘稠状样品质构的测试方法。结果表明，样品的粘稠度可用物性测试仪科学测量，随着粘稠性的不同可选用不同的探头和附件，从而为品质控制、产品研发、标准建立提供测量依据和参考。,
