The art of tasting involves a continuous practice in perceiving, analysing and judging the organolpetic properties of a food product. The technique consists of measuring or evaluating different parameters : appearance, texture and combined smell-taste provided by the senses.
Sensorial analysis
It consists of examining and describing the organoleptic properties of cheese by way of the senses.
The sensorial valuation involves a methodology in which the properties needed to evaluate or outline require a sensorial definition and a technical assessment.
A sensorial analysis is carried out in the following way, taking into account the following parameters:
APPEARANCE
Our sense of sight allows us to detect certain properties of the cheese, both in its external appearance (cut, colour, roughness) as well as its internal appearance (holes, cavities, colour, colour of the paste, etc.). By way of the external apperance of the rind, we are able to see cheeses such as :
- Smooth cut and waxy.
- Mould-ripened
- Smear-ripened
- Plaited
- Rind treated (pepper, wine, oil, etc.)
The colour of the rind could be:
- White, characteristic of soft cheeses.
- White mouldy caused by mould.
- Soft yellow like soft cheeses matured in cellars
- Straw coloured as in sheeps' cheese.
- Orangey yellow produced by surface bacteria. Dark brown in smoked cheeses.
- Reddish due to added paprika.
Heterogenous in mature cheeses which have a natural rind and are preserved in a humid atmosphere. Its colour varies from white to greeny-blue with shades of grey and brown.
The shape or form of the cheeses provide multiple geometric shapes such a:
- Cylindrical, smooth and flat
- Crushed cylindrical or disc-shaped
- Normal cylindrical and plaited.
- Tubular or roller shape
- In the shape of a volcano, or rolled like el Tronchón.
- Conical in the shape of a flat teat almost hemispherical: Tetilla.
- Conical, thinner : San Simón.
- In the shape of a chef's hat: Cebreiro.
- Cubic (Mahón-Menorca, Cantabria).
- Spherical in the shape of a serviette.
The size indicates to us the approximate weight which can be:
- Small for cheeses of less than 1 Kg.
- Medium between 1 and 2 Kg.
- Large from 3 Kg.
By the internal apperance:
When the cheese is cut, we start to discover other properties such as the colour of the paste which may be white in goat's cheeses although it is beige coloured in more mature cheeses.
The youngest sheep's cheeses are of an off-white colour, while the mature ones are soft yellow or straw coloured.
The colour of cows' cheeses varies between off-white in the softest ones and orangey-yellow in the more mature ones. The depth of the yellow is greater for animals who feed in pastures.
In blue cheeses, the paste varies between white and off-white with greeny-blue veins which change to dark or light on their maturity.
In semi-hard cheeses with moudly rind, we detect a cream colour which is similar to the rind produced by surface flora. As we get nearer to the centre, this becomes whiter.
In very mature cheeses, the surround may be pronounced and of a dark colour owing to the oxidisation of fat. A brown paste colour indicates a cheese which is hard and aggressive to the palate.
TEXTURE
This plays a very important role when the time comes to perceive flavours. In order to appreciate the texture, we must turn to our visual and listening organs, as well as to our organs of touch with our fingers and in the mouth (tongue, molars and teeth) known as mechanoreceptors and which play a leading part.
When texture is analysed, it refers to the different properties or attributes which we can encompass into several groups:
a) Properties of the surface
On cutting the cheese and by using the senses of sight and touch, we may detect our first impressions with regard to the texture.
Through sight (visual properties)we can observe if there are any breaks or separation in the mass of the cheese. We may findholes to a greater or a lesser degree and even none at all; drops or drops of water or grease; openings (fissures or slits) andgrain (grain stuck together) to a greater or a lesser degree depending on the type of cheese and its production.
The presence of white spots (crystals) is synonymous with very mature cheeses. These are the ones which appear in highly cured hams called tyrosine crystals.
The size, the shape and the number of holes indicate if the cheese has been correctly fermented. Good cheeses have small holes (< 2mm), which are round or slightly flat, shiny, evenly distributed and of a limited number.
If, on the contrary, the holes are large and numerous, this means that undesirable fermentation has occured owing to coliform bacteria or butyric germs. These micro-organisms produce a large amount of holes making the paste spongy and giving it a bitter and unpleasant taste.
The openings or cavities signal a lack of unity in the paste owing to bad acidification, if the curd has become cold and separated, or defective pressing. Likewise, if the cheese is excessively puffed up, this is symptomatic of the presence of butric germs.
The absence of holes is produced when the curd is allowed to acidify with the whey. The creation of a tiny grain and an excessive amount of time in the press also favours this type of texture. This type of cheese, which has no holes, is known as blind cheese.
When the cheese is cut and we gently run our fingers across the cut area, we will detect the degree ofmoisture and of the roughness which is not immediately obvious (at first sight) if we are looking at a young or aged cheese.
b) Mechanical properties
Are those which we detect when we bite the cheese.
Theelasticity is defined as the figure's ability to rapidly recover its inicial shape after being chewed.
The degree of elasticity will be high in pressed paste cheese when the paste has been heated(Gruyere, Emmental) and negligible or very low in acidic paste cheeses, also known as curd cheese.
The firmness is defined as the resistence which the sample shows when pushed out of shape. It is high in hard cheeses (such as Parmesan, mature cheeses) and very low or negligible in fresh cheeses which have a yielding consistency.
The loss of shape is defined as to how easily it loses shape or stretches when the sample is chewed in the mouth and before it breaks up. Cooked cheeses and those with a rubbery texture will do so to a small degree whereas acidic paste cheeses or very aged cheese will easily crumble.
Thecrumbliness is defined as the characteristic of a product to be easily reduced to small pieces. It is to a high degree in very aged cheeses and those of acidic coagulation (Afuega'l Pitu, goat's cheese) and very low in pressed and cooked cheeses (Gruyère, Comté, Emmental).
And finally, the stickiness is defined as what is involved for the tongue to detach a product from the mouth (on the palate and the teeth). It is to a high degree for soft cheeses having a high fat content, and very low in dry cheeses with a low fat content.
c) Geometric characteristics
They are related to the size, shape and nature of the particles perceived when chewing (graininess). These characteristics may be sandy, grainy, fibrous, crystalline, etc.
After we have finished chewing, we can detect a microstructure of grain which may be a rounded type (more or less hard to chew) or an angular type (which produces an audbile crunch on biting). Round grain which is detected can be smooth, floury; grainy or coarse or fibrous like Mozarella.
The crystals are grains which are somewhat large and angular, and sound crunchy.
d) Other characteristics of texture
There exist certain complex or residual sensations which we sometimes detect when tasting. Although these are fairly infrequent, they can give us certain information.
Thesolubility is defined as the sensation which we have when a sample dissolves very quickly in the mouth. The famous Torta del Casar has a high level of solubility in the mouth.
Theimpression of humidity is the degree of moisture which we detect in the sample. For example, a dry sensation is detected in a cheese which needs us to produce a lot of saliva when chewing, and in order for it to disssolve. On the contrary, there are cheeses, especially the fresh ones, which give out a lot of moisture when being chewed.
e) Other descriptions of texture
Certain cheese have specific - although uncommon - sensorial properties, and one sometimes has to resort to the sense of hearing in order to define them.
For example, when we make a paste with saliva and we feel the cheese dissolving in our mouth like a cream cheese (melting); when it dissolves slowly in the mouth before breaking up like French Comté cheese (plastic); if we feel a fibrous sensation like seaweed or celery as in Mozarella (fibrous). Finally we can have a crunchy sensation in the ear when we chew a cheese which iscrystalline, in the case of Parmesan, or a squeaky sensation to the ear as if we were chewing cork or coarse grained sand, this being typical of cooked cheeses such as Gruyère.
f) Overall impression
It serves as a reference point when tasting is over if the taster is able to appreciate the global texture of the cheese.
Certain words are used which precisely define the overall sensation.
Thus a paste which is closed or compact will be the one whose constituents stick strongly together and do not have holes in them.
A paste which is rubbery will be the one whose consistency is plastic and which becomes pliable after a certain amount of force is used.
A cheese which is doughyis one which is both sticky and slightly floury.
COMBINED SMELL-TASTE
It is perhaps the most important part as, by means of it, we can detect smells, aromas, tastes and other sensations, which, when added to the after-taste and the persistence may help us to describe and correctly identify a cheese.
The smell as well as the intensity in which we perceive it when we raise the cheese towards our nose. This can be of a low intensity, such as for fresh cheese or soft cows' cheeses, or very high in the case of blue cheeses and others with damp rinds.
After smelling the cheese and appreciating its intensity, we are able to identify the family to which it belongs:
- Milk products : yoghurt, butter, boiled milk, cream, buttermilk...
- Plant based foods: herb, hay, green wood, vegetables...
- Floral: honey, rose, violet...
- Fruit: citrus fruit, tropical fruit, apple, apricot...
- Roasted aromas: toast, coffee, chocolate...
- Spices: cloves, nutmeg, mint, pepper...
- Animal smells: barns, manure, rennet...
- Aggressive smells: rancid, ammoniac, bitter, soapy, rottem, spicy up ones nose, musty...
The aroma is defined as a group of sensations which we detect retronasally during tasting.
In order to appreciate this, we must chew it for a few seconds whilst holding our breath, and then breathe out gradually through the nose, with our mouth closed, so that the aromas appear in their full itensity : these can be low in soft and semi-pasteurised cheeses, and high in those made of raw milk.
The family of aromas are indentified in the same way as for those of smells.
The basic tastes or elementary tastes are perceived through the organ of taste (the tongue) and are sweet, savoury, acidic and bitter.
In the oral cavity we also perceive sensations which are irritating, aggressive and strange and which are known as trigeminal sensations which produce annoying flavours such as spicy, caustic, burning, refreshing, and aggressive flavours such as acrid, metallic, medicine-like, etc.
The after-flavour or after-taste is a sensation of smell-taste which appears at the end of the tasting, and which is different from sensations which are felt in the mouth during the tasting.
The after-taste can give smells, elementary tastes and other intraoral sensations which are analysed in the same way as for the senses of smell and aroma.
Finally the overwhelming persistence is the duration of the smell and flavour, that is, the amount of time the taste stays in the mouth which can be a short time of less than 3 seconds, a medium amount of time of between 10 and 15 seconds, and a long time which lasts between 10 and 15 seconds.