|Frost & Sullivan Market Insight||Published: 15 Mar 2002|
by Ivan Fernandez
The drive toward the standardization of sensory evaluation of food came primarily from the need to grade agri-food commodities such as coffee and tea, and other foods such as oils, meats, fish, and so on. This led to the development of professional tasters, inspectors, and consultants. Organoleptic testing - as practiced in the food industry today - involves trained inspectors who assess food on the basis of taste, odor, color, texture, and appearance.
Among the major types of organoleptic testing used are:
Fortunately for consumers, the organoleptic approach is not as imprecise as they assume it to be. Take for instance, the inspection of meat in a slaughter house. Trained veterinarians look for an amazing number of signs of disease or contamination. These include abscesses, inflammation or suppuration, bruising, swelling, emaciation, discoloration, lesions, abnormal odor, urine and fecal contamination, blisters, faulty dressing procedures, improper bleeding procedures, dermatitis, contamination through oils, gases, toxins, adhesions, and specific symptoms related to specific diseases. The thorough examination also involves incisions and examination of internal organs for signs of disease. Their conclusions could lead to trimming of affected portions to salvage as much meat as possible without health risks, or outright rejection of the carcass.
For the organoleptic testing of food ingredients, other parameters such as color, flavor, and mouthfeel are used.
Training in Sensory Evaluation
Whatever the parameters, it is crucial that only trained and experienced investigators perform this form of testing. For instance, training an investigator for the freshness parameter would involve complete familiarization with the food in its most desired state - fresh, uncontaminated, and with the most desirable qualities - followed by familiarization with a range of samples at diminishing stages of freshness. The point where the food sample shows the first signs of decomposition is when a judgement call must be made to reject it. This simulated decomposition under controlled circumstances trains investigators to associate sensory data with specific stages of freshness, and to reach a greater level of certainty as to when food is unacceptable for consumption. This helps refine their evaluation and scoring. New statistical tools and sophisticated computer software make analysis of the scoring data much easier and more consistent today.
The legendary skill of expert wine tasters is perhaps the most romanticized of all organoleptic testing experiences, but behind the hype there is substantial grounding in technique and experience. It is possible for master wine tasters to not only ascertain the variety, quality, and maturity of the wine, but by sensing the sweetness, clarity, intensity of aroma, flavor, color, and ripeness, they can accurately unmask the development of the wine, its connection with similar wines, the growing season it came from, and the style or approach of the winemaker.
Despite the exhaustive training inputs, the confidence that comes from experience, and the support of computer software, serious reservations persist over organoleptic testing. Some of these are:
These reservations are driving some researchers toward the development of devices such as aroma scans and e-tongues, which use sensor arrays to perform the same olfactory and taste analysis, but with the specificity and uniformity which only machines can guarantee. Most of these projects are still far too limited for widespread acceptance in the food industry. The ideal solution would be to use organoleptic testing as one component of a more comprehensive arsenal of tests including chromatography, infrared spectroscopy, microanalysis, microbiological testing, pH testing, moisture and viscosity testing, mold and yeast testing, particle-size testing and so on. Thus, data from organoleptic tests would serve to validate or clarify the findings of other tests.
In all probability, organoleptic testing may never be fully abandoned. After all, despite the several drawbacks, it has its advantages. It is an inexpensive testing method requiring none of the large investments that chemical or microbial testing entail. Conclusions are arrived at rapidly. And most importantly, the assessment instruments - human beings - are readily available. However, the danger of using this method in isolation must be recognized. Only then can the food industry consistently deliver on its crucial promises of food quality and safety.