Quality attributes

The pursuit of product quality over the last few decades has been intense in many companies around the world, but in many sectors of industry, reliability is considered to be the most important quality attribute of the product (Kehoe, 1996). As consumers become more aware than ever of quality, their expectations for reliability are also increasing. Even equipment without obvious safety concerns can have important reliability implications. Most products can, therefore, benefit from the use of sound reliability techniques (Burns, 1994). Reliability prediction, in turn, has the benefit that it gives a quantifiable estimate of the likely reliability that can be assessed to see if this is appropriate for the market (Stephenson and Wallace, 1996). 

Ion exchange and carbon adsorption are unrelated technologies, and often have different objectives. They are however oftentimes used in compliment to achieve high water quality attributes. 

This chapter defines qnality as meeting consumer or customer requirements a product as such has no qnality, but it has physical properties reflected in attributes that can be perceived as qnality after consumption or use. Quality attributes can be defined as characteristics of a product or production process that are observable (by... 

Typical attributes for evaluating food quality are safety, shelf life, color, taste, flavor, texture, health, and convenience. The level of a quality attribute is determined by levels of physical, microbial, physiological, chemical, and biochemical food processes, product composition, and applied technological conditions. For example, a combination of enzyme-degrading colorants, compositions and concentrations of pigments, and food structure properties contribute to a certain color level perceived by consumers. Depending on the match of expectation and experience, certain attributes will or will not be perceived as quality. ... 

While quality was formerly achieved by inspection of final products, it is accomplished now by prevention through controlling critical steps in the production processes along the agri-food chain. Hazard analysis critical control points (HACCP) represent a typical example of such a preventive approach. Although this concept was developed primarily to assure food safety, the basic principle is also applicable to assuring non-safety quality attributes such as color, flavor, and nutritional value. " This section translates the HACCP principles into a critical quality control point (CQP) concept that can be part of a system to assure food quality. 

We have described the CQP concept from a techno-managerial perspective which means that we explicitly pay attention to the roles of both the food and human systems that constitute a food quality management system. The principle beyond the CQP concept is that one need only to control those steps in the process that are critical toward decay of the quality attributes. CQPs must be monitored, documented, and validated in such a way that the system is able to assure a certain quality level. 

This part concerns the actual quality control system by which the critical product and process parameters that impact final quality attributes are monitored and corrected in the production process. CQP monitoring systems can be based on the principle of a control circle as explained in Section 7.1.3. The following principles must be followed ... 

Typical questions that need to be answered are whether the CQP-based system is well designed (validity), whether activities (procedures, instructions, completion of registration forms) related to the monitoring system are executed properly (verification), and whether conditions (checking temperatures, concentrations, and other quality attributes) of processes are really achieved (production process verification). 

Luzuriaga, D.A., Balaban, M.O., and Yeralan, S., Analysis of visual quality attributes of white shrimp by machine vision, J. Food Sci., 62, 113, 1997. 

Role of pectin methylesterase in tomato fruit ripening and quality attributes of processed tomato juice... 

Effect of Reduced PME on Quality Attributes of Processed Juice Fruits from transgenic 3781 and wild-type Rutgers were processed by cold break, hot... 

To measure the scalability of a process, one needs to define the critical quality attributes and to understand the chemistry and processes involved in order to find the limits of acceptability of these critical attributes, and thus, the limits of the scalability of a process. For a chemical process to be functional at large scale it should also be operationally simple, safe and straightforward. 

Investigating coextrusion of com meal and WPI, Onwulata et al. (2003b) found that the melt temperature of the extmdate was more of an indicator of physical properties than specific mechanical energy. Quality attributes such as breaking strength, color, and expansion index were related to melt temperature measured at the die. 

The FDA defines validation as establishing documented evidence which provides a high degree of assurance that a specific process will consistently produce a product meeting its predetermined specifications and quality attributes . Various approaches may be used to fulfill this requirement. 

This chapter will describe the use of nuclear magnetic resonance and magnetic resonance imaging to characterize the quality attributes of foods and for use in process optimization, shelf-life determination and component migration. 

Figure 26, shown earlier, is a simple form of input mapping called table lookup. A more complicated inference mechanism is illustrated in Fig. 30. Here we see a simple example from a fluidized catalytic cracking unit in which multiple product quality attributes can be explained by multiple operating parameters (Ramesh et al., 1992).

The literature lists numerous examples of polymorphism i.e., the existence of several crystal forms of a given chemical that exhibit different physical properties [7]. The conversion of one polymorph to another may cause a significant change in the physical properties of the drug and in critical quality attributes of drug products. 

The most important objective in developing a freeze-dried product is to assure that critical quality attributes are met initially and throughout the shelf life... 

Sterility, freedom from pyrogens, and acceptably low level of extraneous particulate matter are critical quality attributes of all injectable products. Additional critical quality attributes depend on the clinical use of the product. For example, for IV, IM, and SC routes, isotonicity and physiological pH (7.4) are always desirable in order to minimize potential irritation upon injection. Other factors may preclude this, however. If the required dose of drug must be administered in a small volume, it may not be feasible to formulate an isotonic solution. Likewise, solubility or stability considerations may preclude formulation at physiological pH. This explains why formulation pH for injectable drugs varies from about pH 2 to about pH 11. 

Stommel J, Abbott JA, Saftner RA and Camp MJ. 2005. Sensory and objective quality attributes of (3-carotene and lycopene-rich tomato fruit. J Am Soc Hort Sci 130 244—251. 

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