Quality and consumer acceptability 343 of colours with more than 100 million receptors (Meilgaard It is however highly efficient in the detection of spoilage, Irs or taint and often more sensitive and accurate than many sophisticated instruments. When cutting a piece of meat or fish, the level of freshness can be assessed by smell. Jorgensen et al.(1988)has shown a strong relationship between the detection of malodorous volatiles and the spoilage of chilled fish during shelf-life as detected by a pool of trained people 12.2.3 Flavour Flavour is possibly the essential sensory component used to measure the quality of chilled products. If the flavour is undesirable or does not correspond to expectations, the product will be rejected. Flavour is defined as the sum of perceptions perceived in the mouth in the back of the throat and the nose via the retro-nasal route(Piggott 1988). Flavour includes the primary tastes(salty, sweet, acidic and bitter) caused by soluble substances, sensation factors such as astringency, heat or cooling effects and the aroma perception caused by volatile lbstances. Quality criteria associated with flavour relate to the expression of an expected flavour and the intensity of it. 12.2. 4 Texture Texture can be defined as the sensory perception on the physical structure of a food product. During the handling and preparation of food, texture properties can be measured by visual evaluation and touch to identify its overall quality. A hard cheese over matured will look dry with a sensation of mouthdrying and roughness in the mouth. Cheese makers use an agreed methodology to define the quality of cheese in relation to its texture characteristics exture is a complex area of the evaluation of sensory quality, as described and classified in reviews by Bourne(1982) or Civille and Liska(1975). There are three different texture characteristics 1. The mechanical dimension is related to the reaction of the food to stress such as hardness, firmness, cohesiveness or chewiness, as measured by the muscles of the hand, fingers, lips, tongue or jaw. 2. The geometrical dimension is related to the arrangement of the physical components of a product such as size, shape, fibrousness, particles or lumps 3. The surface dimension is related to the moisture and fat content of a product and how they are released during a chewing process A large part of enjoying a meat product involves its texture quality and consumers are well aware of words such as tenderness chewiness or toughnes Slaughtering methods and storage conditions have an influence on the texture quality of fresh fish as described by Love(1988). For pastry-based products such as quiche or pizza, texture is the criterion that influences and therefore bestreceptors, versus millions of colours with more than 100 million receptors (Meilgaard et al. 1987). It is however highly efficient in the detection of spoilage, off-odours or taint and often more sensitive and accurate than many sophisticated instruments. When cutting a piece of meat or fish, the level of freshness can be assessed by smell. Jorgensen et al. (1988) has shown a strong relationship between the detection of malodorous volatiles and the spoilage of chilled fish during shelf-life as detected by a pool of trained people. 12.2.3 Flavour Flavour is possibly the essential sensory component used to measure the quality of chilled products. If the flavour is undesirable or does not correspond to expectations, the product will be rejected. Flavour is defined as the sum of perceptions perceived in the mouth in the back of the throat and the nose via the retro-nasal route (Piggott 1988). Flavour includes the primary tastes (salty, sweet, acidic and bitter) caused by soluble substances, sensation factors such as astringency, heat or cooling effects and the aroma perception caused by volatile substances. Quality criteria associated with flavour relate to the expression of an expected flavour and the intensity of it. 12.2.4 Texture Texture can be defined as the sensory perception on the physical structure of a food product. During the handling and preparation of food, texture properties can be measured by visual evaluation and touch to identify its overall quality. A hard cheese over matured will look dry with a sensation of mouthdrying and roughness in the mouth. Cheese makers use an agreed methodology to define the quality of cheese in relation to its texture characteristics. Texture is a complex area of the evaluation of sensory quality, as described and classified in reviews by Bourne (1982) or Civille and Liska (1975). There are three different texture characteristics. 1. The mechanical dimension is related to the reaction of the food to stress, such as hardness, firmness, cohesiveness or chewiness, as measured by the muscles of the hand, fingers, lips, tongue or jaw. 2. The geometrical dimension is related to the arrangement of the physical components of a product such as size, shape, fibrousness, particles or lumps. 3. The surface dimension is related to the moisture and fat content of a product and how they are released during a chewing process. A large part of enjoying a meat product involves its texture quality and consumers are well aware of words such as tenderness, chewiness or toughness. Slaughtering methods and storage conditions have an influence on the texture quality of fresh fish as described by Love (1988). For pastry-based products such as quiche or pizza, texture is the criterion that influences and therefore best Quality and consumer acceptability 343