Origins and Nature of Sensory and other Performance Attributes in Foods

Abstract

Each quality food individually must “perform” in accordance with a whole host of quality criteria. Food components and ingredients, once consumed, are involved in physiological processes, which may impact health, either for good or bad. However, even before a food is swallowed, the human organism responds to the sensory stimuli which characterise that foods. Many food components act as sensory stimuli. The first three sections of the current chapter therefore describe the perceptions that result from a food interacting with a consumer’s special senses. Three key sensory properties of foods are introduced from an objective, value-neutral point of view. These are the appearance, texture and flavour of foods. Since the current part of the book is designed to provide a focus on foods rather than on the consumer, affective aspects are dealt with in Part 3. Affective aspects of the sensory perception and evaluation of foods involves many different motivational factors, of which expectations are especially important. Food components, and the manner in which they are arranged in a particular food, also determine the performance of a food in a slightly different, but equally important, context. This is to do with the suitability of a raw material for different food technologies, and of a finished food product for different storage and distribution systems. All food processing is designed in some way to render some edible material more fit for some particular purpose, one of the most common goals in food processing being the extension of shelf life. The domestic preparation and cooking of foods generates different quality requirements, particularly on the selection of raw materials, than does industrial manufacturing. Other aspects of fitness for purpose include use context and convenience, although these tend to be more susceptible to individual consumer perspectives. Nevertheless, there are aspects of so-called appropriateness-in-use which are relatively untouched by subjective considerations. Pasteurised milk in the UK is commonly used both as a beverage and for pouring over breakfast cereals, and the appropriateness of both of these contexts is generally acknowledged. However, there will be some people, who would consider one or the other, or both, of these uses as inappropriate. On the other hand, once it is accepted that milk and dairy products are suitable items for human consumption, milk, as a liquid, is clearly used differently from butter, or cheese. Homing in on the cheese offer, clearly, different types of cheese differ in terms of their suitability for different types of application. Some cheeses are soft and can be spread on bread, but cannot be sliced; others are sliceable but not spreadable; yet others are crumbly and cannot readily be used in either of these applications. Some cheeses perform well in cooked dishes, others do not. Another way of looking at the concept of fitness for purpose is in relation to different stakeholders in food supply chains. Whilst the producer and consumer will share certain requirements, they will differ in others. For example, commercial growers of peas will plant varieties that mature simultaneously, as this will facilitate harvest. In contrast, the domestic gardener is likely to require continuity of supply, and will therefore select varieties of pea with extended cropping seasons.