Meat quality is usually defined by compositional quality (lean to fat ratio) and palatability factors such as visual appearance, odour, firmness, juiciness, tenderness and flavour. The nutritional quality of meat is objective yet ″eating″ quality is extremely subjective, as perceived by the human eye. Visual identity Quality meat visual evaluation is associated with the ability of colour, marbling, and water-holding. Marbling is small streaks of fat found inside the muscle and can be seen in the slicing of meat. Marbling has a positive effect on meat taste and juiciness. Meat should have a normal colour, consistent throughout the whole cut. Beef, lamb, and pork will have marbling all over the meat as well. Smell One other quality factor is scent. The item should smell as normal. This will be distinct for each species ( i.e. beef, pork , chicken) but within the species should only vary slightly. Any meat that smells stinky or weird should be avoided. Strength Meat should look firm and not soft. It should be firm when handling the retail kit but not harsh. It should give under pressure, but not be soft indeed. Prudence The juiciness relies on how much water a cooked meat product maintains. Juiciness increases the flavor and aroma, helps soften meat-making chewing easier and stimulating the production of saliva in the mouth. Juiciness is determined by water retention and the lipid content. Marbling around edges and fat helps to hold in water. Losses in water are due to losses of evaporation and drip. Meat aging can increase the retention of water and thus increase the juiciness. Tenderness Has been attributed to multiple factors, such as the age of the animal, gender or the position of the muscle. A significant way of tenderizing meat is through ageing. The carcasses are aged by holding them for longer periods of time after slaughter and initial chilling at refrigeration temperatures. Saveur Smell and flavouring are combined to establish the feeling that the customer has when feeding. These perceptions are based on the smell via the nose and on salty , sweet, sour and bitter sensations on the tongue. Taste of meat is influenced by species type, nutrition, method of cooking, and method of preservation (e.g. smoked or cured).