2APPEARANCE & COLOUR Sight is used to judge appearance and colour. Appearance = size, shape, surface appearance, presentation e.g. garnish and serving dish.Colour = actual colour, colour change due to cooking, colour added by garnish.Appearance and colour used to judge freshness of food.Certain flavour associated with colours e.g. lemon- yellow, strawberry - red, mint - green, lime - green.We expect certain foods to have a certain appearance & colour e.g. mould ok on Stilton cheese but not on bread.Colour lost in processing is sometime replaced artificially for the consumer.
3FLAVOUR Flavour of food is a mixture of smell, taste and mouth feel. Descriptors:acidic, bitter, bland, creamy, piquant, salty, sharp, smoky, sour, spicy, sweet, tangy, tasteless.
4SMELLSmell (olfactory sense): nasal cavity has receptor cells that detect smell.Intensifies flavour.Can be used to determine if food is fresh, rancid or poisonous.Descriptive words: aromatic, burnt, fresh, fruity, pungent, roasted, smoky, sour, spicy, strong.
5TASTE Detected by receptors called taste buds on the tongue. Substances cannot be tasted until dissolved. Saliva dissolves and controls temp. of food.Processing causes flavour loss which is replaced artificially e.g. monosodium glutamate.Recent molecular and functional data have revealed that, contrary to popular belief, there is no tongue 'map': responsiveness to the five basic modalities — bitter, sour, sweet & salty — is present in all areas of the tongue.
7MOUTH FEELNerves in the skin of the mouth are stimulated by thermal or chemical reactions e.g. coldness of ice cream or burning of chilli.Mouth feel helps us detect the texture of food.
8TEXTURE Refers to consistency and rough or smoothness of the food. It is detected by mouth feel and sight.Variety of textures is important in a meal.Very important in bland foods e.g. Lettuce.Mouth feel of processed foods can be improved using additives e.g. humectants – moistness.Descriptors: brittle, chewy, coarse, crunchy, dry, fibrous, fizzy, flaky, grainy, greasy, lumpy, moist, mushy, powdery, smooth, soft, spongy, sticky.
9SOUND Detected by hearing. Noticed during preparation and eating of food.Certain sounds associated with certain foods e.g. sizzling sausages.Used to determine freshness of food e.g. crunchy vegetables or biscuits.Descriptors: bubbling, crackling, crunchy, fizzy, sizzling, snapping.
10(H.L) SENSORY ANALYSISSensory analysis is a science used to measure, analyse and interpret reactions to food characteristics perceived by the senses of sight, smell, touch, hearing and taste.The 5 senses are involved in sensory analysis.The properties analysed are called organoleptic properties i.e. appearance, aroma, texture, flavour, aftertaste.
11(H.L) USES OF SENSORY ANALYSIS Developing new food products.Evaluating products and dishes.Testing modified dishes
12(H.L) SENSORY ANALYSIS TESTS 3 types of test used. Each test has a different aim.TEST TYPEAIMPreference testWhich product is preferred or is a product acceptableDifference testCan a difference be detectedDescriptive testRank organoleptic properties of a product
13(H.L) CONTROLLING TESTS TO GET ACCURATE RESULTS Timing: mid-morning, mid afternoon - taste sensitivity best.No strongly flavoured foods for at least 30 mins. before tests.Temp. of all samples the same.Equal quantity of each sample.Rinsing water needed.Sample containers identical in size, shape, colour.Coding of samples must not causebias e.g. 1,2,3 or a,b,c, not appropriate.Sequencing must be well planned.
14(H.L) SEQUENCING OPTIONS Random: used for large number of samples.Balanced: used in triangle test. Every possible order occurs an equal number of times ( A=sample, B= control), AAB, ABA, BAA, BBA, BAB, ABB.Using a combination of balanced and random sequencing.
15Paired Preference Test (H.L) PREFERENCE TESTSPaired Preference TestTwo samples presented and testers indicate which they prefer.Hedonic Ranking TestOne or more samples are ranked on a verbal scale (5, 7 or 9 point scale) like a lot, like a little, neither like or dislike, dislike a little, dislike a lot.
16Paired Comparison Test (H.L) DIFFERENCE TESTSSimple Paired TestTwo samples are presented. Tester indicates whether they are the same or different.Paired Comparison TestPaired samples are presented. Testers state the difference between the samples based on one characteristic per pair e.g. which of the pair is sweetest, which of the next pair is saltiest etc. Could be used to detect differences between commercial and home-made products.Triangle Test3 samples presented, 2 of the 3 are identical. Tester has to identify which one is different. Could be used to compare brands, or to see if slight changes made to products can be detected
17(H.L) DESCRIPTIVE TESTS Ranking TestsUsed to sort a choice of foods 2-12 samples in order. Food could be ranked (i) by preference or (ii) according to a particular characteristic, e.g. sweetness, colour etc.Rating testsUsed to find out (i) how much a person likes or dislikes a food or (ii) to compare 2 or more foods for different aspects of quality using a 5,7 or 9 point scale.
18(H.L) PRESENTING RESULTS Results must be presented and analysed to find out what changes are needed in the product.Results can be presented on:a star diagram, a histogram, a pie chart,