1 Introduction to Food Quality

1.1 Definitions of Quality

In marketing, sales and the advertising industries “quality” refers to desirable attributes associated with a product or service (Bremner 2000). The business and manufacturing industries, describe quality as “a measure of excellence or a state of being free from defects, deficiencies and significant variations” or ““the totality of features and characteristics of a product or service that bears on its ability to satisfy stated or implied needs” (BusinessDictionary 2015). Quality is discussed frequently in terms achieving consumer expectations, needs and their wants (Botta 1995). Several descriptions for food quality are listed in the Table below.

Establishing product specifications and their measurement is essential for monitoring quality (Bremner 2000). Such principles were adopted in food safety work in the 1960s that led to product specifications for food additives by JECFA (Food and Agriculture Organization of the United Nations 2013). As discussed in Chap. 3, internationally accepted standards of quality are available from the two major organizations, Codex Alimentarius Commission and the International Organizations of Standardizations (ISO).

1.2 Food Quality Attributes

The number quality dimensions currently being studied by food researchers is large (Bremner 2000). A recent survey showed over 7506 articles in the ISI web of science database featuring the phrase “food quality” in the title and nearly 300 reviews (March 2015). Allied terms included phrases such as “total quality management”, quality control, and also quality assurance. Some current ideas surrounding the concept of food quality are considered below.

Quality foods will be affordable, wholesome, and safe in-line with the stated values and objectives of the Agri-food industry (Chap. 2). Food quality can be described also in relation to five dimensions related to sensory characteristics, functional properties, nutritional quality, storage-life and safety (SFNSS) – see Fig. 5.1 and Table 5.1.

Fig. 5.1
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The hierarchical approach to food quality. The diagram shows quality as a general concept and as a defined product standard / specification with an approved method for testing (Adapted from Bremner 2000)

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Table 5.1 General definitions of quality
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Broadly speaking, sensory quality refers to appearance, texture, sound, taste and flavor of foods. Functional properties refer to the ability of some foods to support optimum health. Nutritional quality is dependent on the concentrations and bioavailability of vitamins, minerals, and certain beneficial non-nutrient components; the presence of toxic or anti-nutritional factors in foods also falls under the heading of nutritional quality. Storage life is determined by issues, which affect freshness, acceptability. Safety quality can be discussed in terms of an absence of microbiological, biological, and chemical, physical hazards for foods (Fig. 5.2).

Fig. 5.2
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Dimensions of food quality related to sensory, functional, nutritional, storage life and safety (SFNSS) characteristics

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Individual SFNSS quality characteristics (Fig. 5.2) are interrelated. As an example, storage-life covers a time beyond which there is an unacceptable loss of food safety or sensory quality. All quality dimensions are important but perhaps food safety is the predominant quality attribute (Botta 1995). Few would be happy with unwholesome food. Wider quality attributes. e.g. freshness quality; availability, convenience, and price quality seem to be derivatives of the SFNSS quality.

2 Food Sensory Quality

2.1 Sensory Characteristics

Sensory quality can be evaluated via the human senses. The appearance of food is probably the foremost attribute perceived by consumers that affects purchasing decisions (Moskowitz et al. 2012). It is also well known that the color, hue, and shape determines consumer acceptance of fresh fruits and vegetables (Barrett et al. 2010). Sensory properties such as taste, smell and texture contribute to food preferences, and hedonic ratings – but so far there is no evidence that it affects net food intake or general eating habits (Sorensen et al. 2003). However, some evidence suggests that high glycemic index foods and those high in fat content can produce behaviour characteristic of food addiction and cravings. (Schulte et al. 2015). Finally, an understanding of sensory properties is essential for new food product development (Lyon et al. 1992).

Food sensory evaluation is a multidisciplinary discipline, requiring a knowledge of food science, human physiology, and psychology (Lawless and Heymann 2010). Sensory evaluation can be performed using inanimate instruments or human test subjects. Considerable effort is often needed to establish correlations between human test results and those obtained using instrumental methods of sensory analysis.

Trained wine tasters can differentiate closely related products and may differentiate wines from different regions. Almost everyone can tell when a food contains too much or insufficient amounts of salt or when a tomato is ripened. Obviously, individuals will differ in their personal preferences and so some subjectivity is unavoidable. Nevertheless, factory personnel and sensory panel members can be trained to recognize specific elements of food quality. As an example, fresh produce can be hand-sorted by trained personnel as part of process-lines so that bad or damaged products are excluded. Actually, there are many similar examples of the use of human sensory evaluation as a basis for industrial processing.

Attributes such as nutritional quality seem not to be overtly perceptible to the humans senses. Nevertheless, there are visual cues for nutritional quality such as ripening which is detectable.

2.2 Appearance

Many different characteristics add to or subtract from quality as perceived by the consumer. Examples include the brownness of a piecrust, the shape of a pickle, the wholeness of a product such as canned pineapple, for which the price decreases as the size changes from rings to chunks-same product, different shape. As noted previously, the list of factors which contribute to the appearance of food include, size, shape, surface texture, gloss, presence of dirt, blemishes, imperfections, indentations and the overall color. Appearance is determined by visual perception.

Color is perhaps the most recognizable of a food’s visual attributes and one of the first levels of quality evaluations by the consumer. Color indicates freshness or spoilage of products such as fruits, and vegetables. It may also indicate the strength of a product as in the case of coffee and tea or completeness of cooking, as in the case of French fries or meats. For a food technologist, color can indicate many quality factors. The color of chocolate can give clues as to how it has been stored, and the color of a batter changes with density and can indicate an error in mixing. If too much oxygen is present in a package of dried foods such as tomatoes, a bleached color results.

2.3 Texture

The texture of food is felt by the tongue, palate, teeth, and even the fingers. Texture can be an indicator of freshness in many foods. With aging, many fruits and vegetables experience a breakdown of cell components resulting in a softer, soggy product that indicates low quality and spoilage. Other products, such as crackers and pretzels, must be protected from moisture gain by packaging in order not to soften.

Viscosity and consistency are characteristics that can have both visual and textural quality attributes. Syrups are visually more appealing if thicker, yet this increased viscosity also adds appeal to the feel of the syrup on the food. In some foods, such as ketchup, thickness is a major advertising and marketing feature.

2.4 Flavor

Flavor is a combination of taste and smell but is also influenced by a textural composite of sensations referred to as “mouth feel.” Some foods, such as sauces or gravy that are thicker will often be judged to have the fuller or richer flavor. This perception may be either purely psychological or real. The change in texture may actually affect the volatility or solubility of a flavor compound, increasing the flavor intensity.

Color can also influence the perceived flavor in foods. Taste tests have been done in which the colors of fruit sherbets had been altered but the flavors were not changed. Only 43% of the flavors in the altered samples were identified correctly whereas just under 70% of the unaltered samples received correct responses. One tester even commented on how easy one sample was to identify because there were pieces of cherry in it. He actually tasted a sample of pineapple sherbet (with pieces of pineapple) that had been colored red!

Although color and texture have an effect, flavor is mainly controlled by the mixture of tastes (salt, sour, bitter, and sweet) and the numerous combinations of compounds that are responsible for aroma. The flavor of food is very complex and has not been completely described for many foods. Flavor measurement is largely subjective and thereby very difficult to measure. Differences of opinion on flavors and their contribution to quality result because of this. People have wide ranges of sensitivity to detect different tastes and odors and even when these are detected, individuals differ in their preference. The cultural and biological differences in people make flavor measurement quite difficult.

Some food companies utilize a method of flavor analysis developed in 1948 by Messrs. Sjostrom and Cairncross of Arthur D. Little, Inc. in Cambridge, Massachusetts. “The Flavor Profile” method is based on the concept that flavor consists of identifiable taste, odor, and chemical feeling factors (sensations in the mouth and throat, such as pepper bite) plus an underlying complex of sensory impressions not separately identifiable.

Trained panelists are needed for this method and they are selected based on their abilities to discriminate odor and flavor differences and communicate their perceptions. The panelists must take a series of tests to determine their abilities to notice flavor and odor differences and to identify basic tastes, rank, intensities, and identify common odorants.

After the panelists are selected, they must go through a training period of approximately 60h and 100h of practice sessions. The time of training varies depending on whether the panel will be testing any food or beverage or testing a specific food. Training for a single type of product requires less time. The training generally covers the nature of taste and smell, basic requirements for panel work, and techniques and procedures for reproducible odor and taste work. The development of sensory terminology through exercises and reference standards is also stressed. As the panelists advance, more difficult products are used and flavor situations of a more complex nature are covered. Interpretation and utilization of panel data are covered also.

When the panel is in operation, a quiet, well-lighted, odor-free environment removed from external distractions must be provided. All samples must be presented to the panel under identical conditions and should be analyzed and scored in an identical manner at the same time. A product’s aroma is analyzed first, followed by the flavor, and finally the aftertaste.

Each panel has a leader and four or more members. The leader conducts a product orientation before the panel does the testing. In the orientation, the objectives of the product are outlined and samples to be tested are introduced with similar products to establish a framework for comparison. At this time, the panel will establish a list of character notes for the sample such as vanillin, peppermint, chalky, or buttery. Reference materials will also be chosen (pure compounds that display particular flavor and aroma notes). The panel then decides the best way to present and examine the samples. During the test, each panel member evaluates the sample independently using standardized Flavor Profile techniques and records the findings on a blank sheet. The panel leader, who is also a member of the panel, now has each panelist present his or her findings, records them, and leads a panel discussion to reach a consensus on each component of the description. The final profile may take three to five sessions and after this, the panel leader interprets and reports the results.

The components of the Flavor Profile method are:

  1. 1.

    Determine an overall impression of aroma and flavor, called amplitude. Amplitude measures balance (blend) and body (fullness) of flavor and aroma in the product. It is scored on a point system from 0 to 3 (in 1/2-point increments) with 0 representing no blend or fullness and 3 representing a high degree of blending and fullness.

  2. 2.

    Identification of perceptible aroma and flavor notes. These are called character notes and are objective rather than subjective (i.e., a note may be described as “vanilla“ but not “good”). These include aromatics, basic tastes, and chemical sensations or feeling factors (cool, burn).

  3. 3.

    Intensity of each character note. The degree to which each character note is perceived is “intensity” and the scale is constant over all product categories. The point system such as the one used with amplitude is used, with 0 representing “not present” and 3 being “strong.”

  4. 4.

    Order in which these character notes are perceived. The “order of appearance” is determined through standardized techniques for tasting and smelling because order of appearance will be influenced by the location of taste buds on the tongue, volatility of the components, and texture of the product.

  5. 5.

    Aftertaste. Aftertaste can include tastes, aromatics, and/or sensations. It is an important part of the flavor of a product. The sensations are noted at a specific time after tasting has been completed, usually 1 min. If aftertaste is a major factor, intensity ratings may be given. When color or texture is important to the product’s description, it is also noted in the panel session.

When all data are collected and analyzed, a final test report, including complete identification of the sample(s) and the objectives and duration of the study is given. The methods used to prepare the product, the reference standards used, a summary of the amplitude ratings, and major character notes with their intensities are given. The presence of any off-notes should be mentioned and the order of appearance and aftertaste noted. Any observations of visual and textural qualities are important and should be described.

Another method is The Profile Attribute Analysis (PAA), which is an objective method of sensory analysis that uses an extensively trained panel to numerically describe the complete sensory experience through profile attributes. These are a limited set of characteristics that, when properly selected and defined, provide a complete description of the sensory characteristics of a sample with little descriptive information lost. PAA is based on the Flavor Profile Method in concept and implementation but by limiting the number of profile attributes the panelist measures, it is possible to evaluate four or more samples per session as compared with one per Flavor Profile session.

PAA relies on numerical measures to describe differences among samples, and “Flavor Maps” can be used to display summary statistics.

3 Sensory Evaluation

Because of differences in people’s sensitivity, perceptions, and preferences, it is virtually impossible to create a food that everyone would choose as his or her favorite. The food scientist does have some methods of testing foods to get a consensus of what a majority of the prospective consumers will accept and therefore desire to purchase.

Testing product quality using human subjects is called sensory evaluation or sensory analysis. According to the IFT approved definition, sensory evaluation is “the scientific method used to evoke, measure, analyze and interpret responses to products perceived through the senses of sight, smell touch, taste and heating” (Lawless and Heymann 2010). This highly interesting area which blends psychology, biology, food science and statistics has grown enormously in the past 50 years to become an indispensable part of food product development and consumer science. Experts in sensory evaluation can be accessed on a commercial basis with laboratory facilities located in many of the State Universities, e.g. Washington State University and also Michigan State University. Most food science degree programs may offer training in this area.

There are three classes of sensory evaluation procedures; (i) discrimination tests or difference test are designed to establish when one product is different from a second product in some way, (ii) descriptive testing enables a determination of how much difference there is between products and, (iii) affective testing determines how well a product is liked by the consumer (Fig. 5.3).

Fig. 5.3
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Main sensory evaluation methods. (Adapted from Walker 2004)

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The idea behind sensory evaluation is that product characteristics can be evaluated objectively using the five human senses of sight, smell, touch, taste and hearing. Depending on the type of test, both untrained and trained persons may be used for sensory analysis with the former yielding data that is more representative of the general consumer. A brief outline of this highly specialized area of food science is provided below but the interested reader should refer to one of the many excellent textbooks devoted entirely to this area. (Kemp et al. 2009; Kilcast 2010; Lawless and Heymann 2010; Moskowitz et al. 2006; Stone et al. 2012).

3.1 Discrimination Tests

A discrimination text (difference text) is used to establish whether two products differ in some way. There are three sub-categories of difference tests depending on sample attributes and set of subsidiary information available (Table 5.2).

Table 5.2 Sensory evaluation facilities at Washington State University
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The duo test or paired-comparison test is applicable in situations where there is a simple well-defined attribute of interest (e.g. sweetness). A test subject is presented with two samples (AB, BA, AA, or BB) from which they must pick the sample with a stronger attribute (e.g. sweeter sample). Duo- trio testing is appropriate where there is no simple test attribute but where there is a reference standard available. For duo-trio testing, a subject is presented with the reference sample first, followed by a pair of food (AB) stimuli. The object of the duo-trio test is to pick the sample (A or B) most similar to the reference sample.

In the triangle-test (Fig. 5.5) a test subject is given three samples two of which are identical and asked to identify the odd sample. Assuming little or no difference between products, the “odd” sample would be identified correctly in 50% of instances or alternatively, only 50% of participants would identify the odd sample in any given trial. If the proportion of participants identifying the odd sample is different from 50% by a significant margin, it could be concluded that there was a detectable difference in the samples. The triangle procedure may be used to establish whether a particular product formulation is as acceptable as another is. Another use for difference tests is a situation in which a change in formulation is desired to reduce production costs.

3.2 Descriptive Testing

Descriptive testing refers to a series of related methods that evolved independently starting from the 1940s. The common feature of descriptive testing appears to be use of trained panelist. The aim of descriptive testing procedures is to evaluate products characteristics according to a pre-agreed intensity scale. A listing of some of the major descriptive tests (Table 5.3) and a detailed account of each is available (Lawless and Heymann 2010; Stone et al. 2012). Some descriptive testing, e.g. flavor and texture profiling are qualitative but QDA translates product attributes to numerical scales which can then be subjected to conventional analysis (Fig. 5.4).

Table 5.3 Descriptive analysis methods
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Fig. 5.4
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A spider chart showing effect of diet on flavor descriptors for African tilapia fed varying amounts of corn gluten feed (CGF), corn gluten meal (CGM) or cord distillers grain soluble (CDGS) (Wu et al. 1996)

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Arguably, QDA is the most widely applied format for descriptive testing (Table 5.3). Skipping through the developmental aspects, the main elements of QDA are described as, (a) panel selection and training, (b) development and agreement of the sensory descriptors by panel members, (c) testing of products against the agreed descriptors and scales, and (d) robust statistical analysis typically involving ANOVA testing. The results of QDA is often presented in the familiar spider web plots, cobweb or radar plot (Fig. 5.4).

3.3 Affective Testing

Affective testing (hedonic testing) is intended to determine consumer acceptability and relative preferences for different products. The “acceptance” test usually requires a large number of individuals who represent the target group of potential consumers. For example, if you were testing a flavored cereal advertised by a cartoon character, you would use a panel of children. A gourmet-frozen entree would require a more mature panel. The panel here requires little training and is usually given a score sheet (Fig. 5.5) which rates different sensory attributes (appearance, odor, texture and flavor) from “excellent” to “inedible.” Products may be scored using a “hedonic rating,” which uses a numerical score of 9 for “excellent” and a score of 1 for “inedible.” A mathematical average can now be determined for the food’s acceptability. (Kemp et al. 2009; Kilcast 2010; Lawless and Heymann 2010; Moskowitz et al. 2006).

Fig. 5.5
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Triangle test score sheet

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4 Instrumental Sensory Analysis

4.1 Objective Analysis of Food Quality

Instrumental methods of analysis can be deployed that provide surrogate measures of sensory quality. For instance, chemical odorants that determine the flavor and smell of foods can be measured using a gas chromatograph. Most dissolved chemicals can be measured instrumentally – to provide an index related to taste. Various physical attributes of foods, which affect their texture, can be measured using viscometers and rheological instruments.

Human testing can be costly for industry. Therefore, a lot of research is being conducted to develop instrumental methods for assessing food quality that could replace human sensory analysis. Methods that compare sensory and instrumental analysis of quality dealt with fatty foods (Waltking and Goetz 1983), apple cider and juice (Williams et al. 1983). Other reports deal with quality attributes for wine (Rapp 1998), cheese (Foegeding and Drake 2007), snack foods (Paula and Conti-Silva 2014), meat, lamb and poultry (American Meat Science Association 2015; Oltra et al. 2015; Luckett et al. 2014) and crispy foods (Roudaut et al. 2002). In the rest of this section, we describe some of the main instrumental method for assessing a range of food quality attributes (Otles 2008; Sliwinska et al. 2014).

4.2 Colorimetry of Foods

The color of liquid foodstuffs can be determined using colorimeters, which are instruments that measure light absorbance or transmittance when a sample is illuminated with visible radiation. When using transparent liquids, the degree of absorbance is related to color but such instruments are not routinely used for color measurement. For turbid samples, we can measure the transmittance or turbidity of a sample according to the degree of light transmitted. The major limitation associated with colorimetry is the need for transparent liquid foods devoid of particles of all types.

The color of solid foods can be readily measured using a reflector-meter. According to the tristimulus principle, the color of any object can be determined in terms of degree of by which the three primary colors (red, blue, green light) are reflected. The color of a solid object is measured according the XYZ scale, using values for X (red), Y (green) and Z (blue). The CIE color scheme was invented by the International Commission on Illumination (CIE; from the French, Commission Internationale de l’Eclairage) to try to mimic how humans perceive color via the rods and cones. The CIE color system is the basis for the reflector-meter, which is one of most popular instruments for measuring the color of solid foods, e.g. the Minolta Konica reflector-meter. The CIE L*a*b* and Hunter Lab. systems are the two alternative trismulus systems for measuring the color of solid objects (HunterLab 2008; 2012). The Hunter Lab reflectometer provides three numbers according to a degree of red-green (a) scale, (b) yellow-green scale and (L) lightness-darkness scale. A recent survey of the types of instrumentation employed for color measurement in the meat industry found that the majority of reports from the United States and the EU tended to employ a Minolta Konica reflector-meter, or Hunter Lab instruments (Tapp III et al. 2011). A recent development which seems likely grow in prominence is the use of Computer based vision and robotic systems for color measurement and for high-throughput sorting of food samples (Vyawahare et al. 2013).

4.3 Texture Monitoring Instruments

Food texture can be measured in a number of ways. Generally speaking, however, texture is the measure of resistance to force. Examples of the different forces are numerous. “Compression” is tested on foods that, when squeezed, remain in one piece, for example, bread. “Cutting’‘ is a force that goes through the food, thus dividing it, for example, an apple. A force applied away from a material resulting in tearing or pulling apart is termed “tensile strength,“ for example, donuts or breads. A force where one part of the food passes another is “shearing,” as in the chewing of some candies and gum. When grading some foods, such as beefsteak, all of these factors can come into play. This branch of study is called food rheology.

Historically, the food technologist had many empirical tools to measure texture and control quality during processing. These include the “consistometer” for viscosity, the “squeeze-tester” for softness of bread, the “penetrometer” or “tenderometer” for tenderness in raw beef or baked goods or spreadability in margarine, and the “succulometer” which measures succulence by squeezing juice out of food. A range of many different types of equipment needed to measure various texture attributes can be found in the following reference (Kramer and Szczesniak 1973).

Modern commercial “all-in-one” texture analyzers can be fitted with a range of probes and accessories in order that one instrument may be used to measure multiple texture parameters. Examples of commercially available texture analyzers for use in the food industry settings include the TA.XTPlus texture analyzer from Stable Micro Systems Ltd. and distributed in North America by Texture Technologies (Texture technologies 2015). Two other instruments, the Texture Analyzer-TMS-PRO (Food Technology Corporation Ltd), and CT3 Texture analyzer (Brookfield Engineering Laboratories Inc 2015) are also widely used for a range of solid food product groups for a variety of technologically relevant measurements (Table 5.4).

Table 5.4 Applications of modern texture analyzers
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As noted above, the texture of solid foods may be measured in a variety of ways but the technique called texture profile analysis (TPA) is deserving of special mention. Prior to the development of TPA in the 1960’s several instruments had to be deployed when measuring different texture attributes; for instance, Kramer and Szczesniak 1973 (p. 101) listed 40 or more in-house instruments for measuring food textures. The essence of TPA is the application of two successive compression forces to a solid food whilst measuring the structural resistance to deformation. Many textural attributes may be calculated based on the force-distance trace obtained from two-fold compression data. The TPA data provides information on a host of textural attributes e.g. hardness, cohesiveness, elasticity etc. (Fig. 5.6).

Fig. 5.6
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A typical texture profile analysis derived from double sample compression (Courtesy, Stable Micro Systems, Ltd). Product characteristics are defined as Hardness = Maximum force at peak-1; Cohesiveness = Area peak-2/Area peak-1 or Area 5/Area 4; Springiness = Ratio of a product’s original height. Distance 2/Distance 1 or Time 2/Time 1; Gumminess = Hardness x Cohesiveness = Hardness x (Area peak-2/Area peak-1); Chewiness (solids) = Hardness x Cohesiveness x Springiness; Resilience = Peak-1 (Area 4/Area 3)

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According to some accounts, TPA methods were first developed by Dr. Alina Surmacka Szczesniak, a sensory food scientist, then working at General Foods. The technique introduced five principal textural characteristics for solid foods (hardness, cohesiveness, adhesiveness, viscosity, and elasticity) as well as three other derived parameters (brittleness, chewiness, and gumminess) and how these could be measured using what was essentially one texture analysis machine (Friedman et al. 1963). Later TPA was adapted to the commercially available Instron Universal Testing machine by Professor Dr. Malcolm Bourne (Cornell University). TPA is currently one of the most common forms of texture analysis (Chen and Opara 2013; Rosenthal 2010).

4.4 Electronic Noses

In the mid-1980s, researchers at Britain’s Warwick University used work done by the U.S. military in developing polymers that could conduct electricity to help planes evade enemy radar, and applied it to the development of the first electric nose (Mielle 1996). In their 1982 article which appeared in “Nature” magazine, Krishna Persaud and George Dodd patterned their new device on the mammalian olfaction system (Persaud and Dodd 1982). They realized that the human olfaction system contains many millions of sensory cells but that these could be separated into relatively few classes; according to current estimates there may be 1000 different genes coding for different odor receptors but 70% of these genes are non-functional meaning that there are approximately 200 different types of odor receptors.

On the other hand estimates for the number of different odors detected by humans range from 10,000 to one trillion. How then is the human nose able to distinguish between thousands of different smells? In olfaction, the 200 different receptors cells respond to vastly higher numbers of smell compounds perhaps depending on which sub-groups are stimulated, and the order in which these sensory cells become stimulated; one possible analogy is that many tunes may be composed using a fixed number of musical notes. The electric nose works on similar principles to detect very large numbers of odorants according to the overall patterns of responses generated via limited numbers of sensors. Advance statistical methods, are used to aid pattern recognition such as principal component analysis (PCA) and artificial neural networks (ANN).

According to current predictions electronic noses may find increasing applications in relation to food quality assessment, food spoilage detection, fermentation monitoring, biomedical applications and environmental monitoring (Gutierrez and Horrillo 2014; Loutfi et al. 2015). In medicine, for example, ailments such as diabetes and some liver and kidney diseases cause the production of certain odors that appear in the breath. Because the machines are more precise than the human nose in finding the specific odor components, scientists see its use as a diagnostic tool increasing in the future.

In the food industry, electronic noses could be used to detect specific aromas indicating spoilage, off quality, or use of a particular additive. This “technology of the future” is being used now in a number of applications and wherever the same component is being tested for in many samples, it is very useful. The use of this technology along with flavor panels gives the food scientist an additional tool to ensure a consistent, safe, high-quality food supply.

5 Processed foods quality and health

Economic experts propose that public health should be included as one measure for processed foods quality in addition to elements summarized in Fig 5.2 (food safety, sensory, functional, storage life). Moreover, the environment, climate change, and globalization are quality-related challenges facing the food processing industry. A central concern is the nutrition transition from traditional diets towards more ultra-processed foods that are known to be linked with some chronic diseases (Martinez-Perez et al. 2021). It is reasoned that, external oversight and regulations (e.g. labelling and taxation of added sugar) are needed to discourage unhealthy ultra-processed food products (Smith et al. 2011; Baum 2013; Qaim 2017; Hall 2018; Pedroza-Tobias et al. 2021). Some of these controversies are discussed in the sections on adult food literacy (Chap. 6) and ultra-processed foods (Chap. 11, Sect. 5) with the focus on food science and nutrition science.