The role of organoleptic The role of organoleptic inspection in food inspection in food

qualificationqualification

Food quality components:Food quality components:

Food hygiene propertiesFood hygiene properties Physical propertiesPhysical properties Chemical propertiesChemical properties Packing and labellingPacking and labelling Organoleptic propertiesOrganoleptic properties

Exterior characteristics: surface, colour, Exterior characteristics: surface, colour, packing, shape, formpacking, shape, form

OdourOdour TasteTaste TemperatureTemperature Substance and structureSubstance and structure

OrgansOrgans

eyes, nose, tongue and mouth, fingers, eyes, nose, tongue and mouth, fingers, ears(!)ears(!)

Using the human organs of senses as Using the human organs of senses as measurement tools raises some problems:measurement tools raises some problems: the human organs of senses are liable to the human organs of senses are liable to

sensorial errorssensorial errors the human organs of senses are fatigablethe human organs of senses are fatigable there is a big biological variabilitythere is a big biological variability

some bitter substances could be percepted only in some bitter substances could be percepted only in higher concentration by some peoplehigher concentration by some people

some people are sensitive to the chumestrol-content of some people are sensitive to the chumestrol-content of the carrotthe carrot

Sense of TasteSense of Taste ~6 million receptors on the tongue (dynamic ~6 million receptors on the tongue (dynamic

balance), balance), with aging death>production of receptors → ~1,5-2 with aging death>production of receptors → ~1,5-2 million million

4 basic tastes (sweet, salty, sour, bitter), but there 4 basic tastes (sweet, salty, sour, bitter), but there are some more tastes:are some more tastes: taste generating pain sensation (capsaicine)taste generating pain sensation (capsaicine) taste influencing the sensation of substance characteristics taste influencing the sensation of substance characteristics

(alkaline materials or contractive materials like alum)(alkaline materials or contractive materials like alum) metallic taste (FeSO4×7H2O)metallic taste (FeSO4×7H2O) the “umami” taste (complex taste, the taste of Na-the “umami” taste (complex taste, the taste of Na-

glutamate; it’s salty, sweet, bitter and metallic at the same glutamate; it’s salty, sweet, bitter and metallic at the same timetime))

Haller’s taste catalogue contains 12 basic tastes (for Haller’s taste catalogue contains 12 basic tastes (for example there is taste generating changes in heat example there is taste generating changes in heat perception – menthol)perception – menthol)

Sweet tasteSweet taste

natural (sugars; mollenin – 2000 times natural (sugars; mollenin – 2000 times sweeter than sucrose; miraculum – changes sweeter than sucrose; miraculum – changes the taste effect: makes sweet from sour)the taste effect: makes sweet from sour)

artificial (sugar-alcohols, ketones, esters, artificial (sugar-alcohols, ketones, esters, etc.) – they were developed during the etc.) – they were developed during the research of diabetesresearch of diabetes

Intensity of the sweet taste increases with Intensity of the sweet taste increases with water-solubility.water-solubility.

Making symmetric structure from an Making symmetric structure from an asymmetric, the sweet taste changes into asymmetric, the sweet taste changes into bitterbitter

SourSour, salty, salty taste taste

Sour taste: Sour taste: acidsacids Depends from:Depends from: acid concentration, pH, acid concentration, pH,

dissociation rate, other food components, the dissociation rate, other food components, the buffer effect of salivabuffer effect of saliva

Intensity:Intensity: acetic acid (the least acetic acid (the least intensive)→lactic acid→malic acid→citric acid → intensive)→lactic acid→malic acid→citric acid → tartaric acid (most intensive)tartaric acid (most intensive)

Around the perception threshold Around the perception threshold (0,02g/100cm3) the typical salty (0,02g/100cm3) the typical salty substances (like NaCl) seem to be sweet, substances (like NaCl) seem to be sweet, they appear to be salty only around they appear to be salty only around recognizing threshold (0,08g/100cm3).recognizing threshold (0,08g/100cm3).

Salty taste: salt like materialsSalty taste: salt like materials

substance taste substance taste

MgCl2 salty-bitter K2SO4 sour-bitter

NH4Cl salty-sour BeSO4 sweet-sour

NaHCO3 salty-sweet Pb-acetate sweet (!)

MgSO4 bitter-sweet Salts of heavy metals

metallic

Bitter tasteBitter taste

Substances containing nitrogen, Substances containing nitrogen, anorganic salts, tanning materials, anorganic salts, tanning materials, alkaloids (caffeine, quinine, alkaloids (caffeine, quinine, morphine, nicotine), etcmorphine, nicotine), etc

““Taste blindness”: some people (and Taste blindness”: some people (and monkeys) don’t percept the bitter monkeys) don’t percept the bitter taste.taste.

Factors influencing personal values Factors influencing personal values of taste sensing thresholdof taste sensing threshold

pH of the samplepH of the sample temperature of the sample (no refrigeration temperature!)temperature of the sample (no refrigeration temperature!) clearness of the aroma substanceclearness of the aroma substance the water medium the water medium size of the tongue surfacesize of the tongue surface number of receptors on unit surfacenumber of receptors on unit surface Physical and psychical condition of the judgePhysical and psychical condition of the judge (judge has to (judge has to

know his program 2 days before the inspection – no coffee, know his program 2 days before the inspection – no coffee, smoking, big breakfast at the morning,etc.)smoking, big breakfast at the morning,etc.)

Circumstances of the inspectionCircumstances of the inspection (noise, light, temperature, (noise, light, temperature, colour of the wall, etc.)colour of the wall, etc.)

part of the day (a.m. is the best – between 10-11 hours)part of the day (a.m. is the best – between 10-11 hours) experience of the judge (Can be learned and improved by experience of the judge (Can be learned and improved by

practicing)practicing) method of the inspection (drop-method, spoon-method, method of the inspection (drop-method, spoon-method,

etc.)etc.) other factorsother factors

Sense of SmellSense of Smell Aroma:Aroma: odour (in mouth) + odour (in nose) + odour (in mouth) + odour (in nose) +

tastetaste Scent:Scent: pleasant smell pleasant smell Smell materials: common characteristics are: the Smell materials: common characteristics are: the

–OH, –CO, –COOH or –NH2 group–OH, –CO, –COOH or –NH2 group Factors influencing the sense of smell: Factors influencing the sense of smell:

temperature (optimal: 25-30°C), part of the day temperature (optimal: 25-30°C), part of the day (a.m.), age (20-40 years), sex of the judge (a.m.), age (20-40 years), sex of the judge (female), smoking (no), experience (high)(female), smoking (no), experience (high)

Anomalies of the sense of smell:Anomalies of the sense of smell: hypozmiahypozmia: decreased sense of smell: decreased sense of smell hyperozmia:hyperozmia: hyper sensitivity (women) hyper sensitivity (women) anozmia:anozmia: no sense of smell (above 80 years of age) no sense of smell (above 80 years of age) merozmia:merozmia: no perception of specific smells no perception of specific smells autozmia:autozmia: sensation of smell without smelling substance sensation of smell without smelling substance

Textural characteristicsTextural characteristics

Rheological classification of food:Rheological classification of food: liquidliquid cell tissue structure (vegetables, fruits)cell tissue structure (vegetables, fruits) gel structure (cheese, jelly)gel structure (cheese, jelly) fibre structure (meat and meat fibre structure (meat and meat

products)products) plastic (butter, margarine)plastic (butter, margarine) hard, fragile (cookies, chocolate)hard, fragile (cookies, chocolate) complex (bread)complex (bread)

Choosing the judgesChoosing the judges: examination of : examination of tasting-, smelling- and colour recognizing tasting-, smelling- and colour recognizing

abilitiesabilities Recognizing the tastes: Recognizing the tastes:

SourSour: : citric acidcitric acid BitterBitter: : caffeinecaffeine SaltySalty: : NaClNaCl SweeSweet: t: sucrosesucrose UmamUmami: i: Na-glutamateNa-glutamate MetallicMetallic: : FeSO4×7H2OFeSO4×7H2O distilled waterdistilled water

methods:methods: draught methoddraught method spoon-test (more exact definition of amount)spoon-test (more exact definition of amount) drop-test (3 on the tongue – it’s the best; usually it turns drop-test (3 on the tongue – it’s the best; usually it turns

to ridiculeto ridicule

Recognizing the smells:Recognizing the smells: stable smellstable smell : :ammoniaammonia bitter almond smellbitter almond smell: : benzaldehidebenzaldehide sweat smellsweat smell: : butyric acidbutyric acid VinegarVinegar: : acetic acidacetic acid nail polish smellnail polish smell: : amyl-acetateamyl-acetate hospital smellhospital smell: : phenolphenol VanillaVanilla: : vanillinvanillin butter aromabutter aroma: : DiacetileDiacetile AniseAnise: : anetoleanetole method: put cotton-wool in a bottle, drop 0,5 method: put cotton-wool in a bottle, drop 0,5

cm3 of substance on itcm3 of substance on it

Recognizing the coloursRecognizing the colours

Ishikawa-test (ophthalmologic sight-Ishikawa-test (ophthalmologic sight-test)test)

-10 bottle dilution series of 3 basic -10 bottle dilution series of 3 basic colours (red, yellow, greenish-blue); colours (red, yellow, greenish-blue); should be put in ordershould be put in order

Faults in judgments:Faults in judgments:

perceptionalperceptional: for example attractive packing: for example attractive packing expectional:expectional: positive prejudice positive prejudice habituationhabituation: too high number of samples, : too high number of samples,

with little differenceswith little differences contrast:contrast: too big differences between too big differences between

samplessamples settle:settle: the judge uses the middle values in the judge uses the middle values in

judging by pointsjudging by points tolerant approach:tolerant approach: in case of favourite in case of favourite

productproduct

The perfect judge:The perfect judge:

has to have normal organs of senses, has to have normal organs of senses, healthy, rested, with positive healthy, rested, with positive approach, curious, compliant, approach, curious, compliant, teachable, conscientious, capable, teachable, conscientious, capable, concentrated, calm, well-balanced, concentrated, calm, well-balanced, free from prejudice, critical, self-free from prejudice, critical, self-critical, reliable, disciplined, accurate, critical, reliable, disciplined, accurate, self-confident, unimpressionable, with self-confident, unimpressionable, with good sense of phrasing, qualified good sense of phrasing, qualified

Methods of organoleptic Methods of organoleptic inspectionsinspections

One test:One test: the sample is compared with a standard the sample is compared with a standard sample. First step: examination of the standard sample, sample. First step: examination of the standard sample, then this standard is removed. Second step: examination then this standard is removed. Second step: examination of samples (there are standard samples and samples to of samples (there are standard samples and samples to be examined in the sample series). The judges have to be examined in the sample series). The judges have to differentiate the samples from the standard samples. differentiate the samples from the standard samples. Advantage: the sample series can be examined however Advantage: the sample series can be examined however long. Disadvantage: the samples have to be compared long. Disadvantage: the samples have to be compared with a vision of memory.with a vision of memory.

Duo-trio testDuo-trio test: : Tetrad testTetrad test: 2 kinds of samples in 4 pots signed with : 2 kinds of samples in 4 pots signed with

codes. Aim: which two are the same.codes. Aim: which two are the same. Two from five testTwo from five test: 5 pots: sample N: 5 pots: sample Noo1 is in 2 pots, N1 is in 2 pots, Noo2 in 2 in

3 pots.3 pots. Pair testPair test: there are 2 kinds of this test:: there are 2 kinds of this test:

Differentiation of two samples: is there a difference between Differentiation of two samples: is there a difference between A and B? (The “no difference” answer should be allowed.) A and B? (The “no difference” answer should be allowed.)

Indication of the direction of the difference (Which is more Indication of the direction of the difference (Which is more intensive? Which is better?, etc.)intensive? Which is better?, etc.)

Descriptive organoleptic Descriptive organoleptic inspectionsinspections

The judgment should be made by an expert The judgment should be made by an expert of the specific sample/product. The sample is of the specific sample/product. The sample is compared with standards (Codex compared with standards (Codex Alimentarius, International standards, etc.). Alimentarius, International standards, etc.).

There are two kinds of properties which There are two kinds of properties which should be examined during the comparison:should be examined during the comparison: positive characteristics, which should be presentpositive characteristics, which should be present disqualifying characteristics, which should not be disqualifying characteristics, which should not be

presentpresent The presence/lack of positive and The presence/lack of positive and

disqualifying characteristics should be disqualifying characteristics should be detailed in the result. detailed in the result.

Decision: passed, not passed.Decision: passed, not passed.

Methods for quantitative analysisMethods for quantitative analysis

Extended examination of differences:Extended examination of differences: DescriptionDescription ScaleScale Grading:Grading: the samples are put in order on the samples are put in order on

the basis of a specific property, then a the basis of a specific property, then a grade point is given. grade point is given.

3) 3) Judging by pointsJudging by points: : a) 100 points, point subtraction scale a) 100 points, point subtraction scale b) 5 points, weighting scale (or 20 points scale)b) 5 points, weighting scale (or 20 points scale)

Every property can obtain 5 points, the different Every property can obtain 5 points, the different importance of the properties is weighted with factors importance of the properties is weighted with factors (the factors’ sum has to be 4, so the sum of points(the factors’ sum has to be 4, so the sum of pointsobtained will be 20). obtained will be 20).

Usually 4 properties are examined: appearance, Usually 4 properties are examined: appearance, odour, taste and substanceodour, taste and substance

Other methodsOther methods Matching together a concentration with sensation:Matching together a concentration with sensation: for for

example: comparing a sweetener (saccharin) with example: comparing a sweetener (saccharin) with different sugar-solutions. Result: which concentration different sugar-solutions. Result: which concentration of sugar-solution generated the same sweet taste of sugar-solution generated the same sweet taste perception as saccharin?perception as saccharin?

Pouring method:Pouring method: for example: we pour clear water to for example: we pour clear water to concentrated sugar-solution, and we try to find the concentrated sugar-solution, and we try to find the concentration which generates the same sweet taste concentration which generates the same sweet taste perception as saccharin. If it’s found → we measure perception as saccharin. If it’s found → we measure the sugar-solution’s concentration with refractometry the sugar-solution’s concentration with refractometry → Result: “The sweetener (saccharin) is as sweet as a → Result: “The sweetener (saccharin) is as sweet as a … concentration sugar-solution.”… concentration sugar-solution.”

Consumers’ judgements:Consumers’ judgements: Popularity surveysPopularity surveys Scales:Scales: scale of popularity scale of popularity Observing the consumersObserving the consumers Examination of focus groupsExamination of focus groups