Open access peer-reviewed chapter

Harmony (QHV): Practical Experiences with an Additional Sensory Criterion for the Quality Assessment of the Grade “Extra Virgin Olive Oil”

Written By

Dietrich Oberg

Submitted: 20 December 2021 Reviewed: 01 February 2022 Published: 25 April 2022

DOI: 10.5772/intechopen.102994

From the Edited Volume

Olive Cultivation

Edited by Taner Yonar

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Well over 100 laboratories and tester groups worldwide check about 2,4 Mio tons of olive oil according to the Reg. (EWG) 2568/91 in its actual version or according to the method COI/T20 Doc.No.15. Pursuant to the regulation around 50% is EVOO. In order to evaluate these versatile typical sensory characteristics, the additional criterion “Quantified Harmony Value” (QHV) was developed. The QHV assessment is evaluated for all EVOO with special focus on the mass market. The method is based on the relationship of smell to taste and the interplay with the attributes such as bitter and pungent, on the cleanliness of all attributes and flavor, on the evaluation of complexity and persistency. All these findings play an important role in olive oil competitions—organized exclusively for a small number of premium products. But the higher the quality, the lower the quantity. Therefore, large quantities of EVOO need as well objective differentiations. But for the largest share of EVOO produced for millions of consumers, there are officially no distinguishing criteria. The additional criteria QHV close this gap and make it objectively possible to discriminate all oils in the EVOO category at commercial level. The study at hand explains the relevant method and shows the positive development of the last 10 years using the example of the importing country Germany.


  • grade extra virgin
  • harmony criteri0n
  • method
  • profiling
  • experiences
  • commercial benefits

1. Introduction

Regardless of the quantities harvested, the average percentage of virgin olive oil of the highest category (EVOO) in the three main producing countries, Spain, Italy, and Greece, is estimated at about 50% per year [EC Statistics, 1998]. The remainder has chemical or sensory defects that, depending on their intensity, must be classified as virgin olive oil (VOO), ordinary virgin olive oil (OVOO), or lampante virgin olive oil (LVOO) according to EEC-Regulation 2568/91 or International Olive Council (IOC) Standard. Olive oil is one of the most controlled vegetable oils in the world. Nevertheless, the EU classified olive oil as one of the most adulterated food products, although it is subject to a number of EC regulations [1].

Olive oil is one of the few fruit oils, along with avocado oil and palm oil. Most vegetable oils known to us are seed oils. The olive fruit goes through many important steps on its way “from tree to bottle” that can affect its quality. The fruit itself belongs to a range of well over 500 different varieties. They differ in the size of the fruit, size and type of leaves, ripening, kernel/pulp ratio, amount of oil, unusual minor components, and among other things, especially in taste. Some varieties are used only as table olives, others for both purposes, but most are processed into oil. In the plantations, the olive trees are planted traditionally, intensively, and super intensively. The spacing between trees has decreased from 7.50 × 7.50 m (traditional) to 3.50 × 3.50 m (intensive) to trellis-like cultivation as in the case of wine (super intensive). The main reasons for this type of cultivation are an improvement in yield and the use of harvesting machinery. Harvesting is the most expensive part. The most important factor for a good-quality oil is the right time of harvesting or the optimal ripeness of the fruit. After harvesting, the quality of the fruit can only decrease, as fermentative degradation processes begin immediately after harvesting. Picking the olives by hand is often the only way to harvest the fruit, as the cultivated areas make it impossible to use harvesting machines. It is important that the fruit is not damaged during harvesting, and the waiting time before pressing or extraction in the decanter should not exceed 24–48 hours. Pressing requirements range from high quantities of olives in a correspondingly short time to achieving a particular quality—regardless of quantity—with pressing temperatures or conditions during extraction in the decanter, high polyphenol content, and excellent aroma and flavor.

Ultimately, each of the above processing steps results in a wide range of different qualities in terms of aroma (smell and taste), complexity, nutritional composition, and oxidation stability.

When the oil is ready for marketing, each producer follows his own way of marketing. Depending on the size of the crop, some producers handle storage, bottling, labeling, and marketing themselves. For other producers, local cooperatives handle the larger quantities of oil. In many cases, there are buyers, brokers, and sellers who sell or buy large quantities to large bottling companies in the producing countries. These producing and bottling companies work for large food chains in Europe and around the world. Up to 80% of EVOO is sold as so-called “private labels” in discount stores and large grocery chains, at least in Europe (Figure 1). However, where large volumes are marketed, the trade tries to buy the oils at a minimum price. Inevitably, quality can suffer as a result, especially for EVOO grades marketed as part of so-called borderline oils. These include really bad tasting and sometimes slightly defective oils, which consequently would have to be officially retested to get clarity for the classification.

Figure 1.

80% of EVOO is sold as “private label” to supermarkets and discounter chains.

1.1 The classification is something like a basic division of the total amount of olive oil

The views of market participants and consumers must be differentiated, with the question of supply and demand and the requirements for quality and price in the foreground. In the various countries, the share of olive oils in the different categories varies greatly. There are countries where on average 80% EVOO and only 20% VOO and OO are consumed. In other countries, it is even only 30% EVOO and 70% virgin olive oil, refined olive oil, and olive pomace oil. The classification is carried out by the legislator within the framework of a marketing regulation. The classification is based on the data of chemical and sensory analysis (Figure 2). Although the technology of oil extraction (pressing, malaxation [2], decantation), the climatic conditions, and the possibilities of chemical analysis have changed considerably in the last 30 years, there have been only minor adjustments to the legal regulations in this respect—especially with regard to the chemical control parameters. The classification is granted on the basis of the 1991 regulations in force, if the chemical analysis (officially 27 parameters) meets the requirements and the sensory test in the so-called panel test (PT) have been passed. The PT is performed by a regional, national, EC, or IOC accredited official panel of 8–12 trained olive oil tasters. It is used to verify conformity with the requirements of Regulation (EC) 2568/91, as amended [1]. Before receiving EC approval, panels must be accredited according to EN ISO 17025 (2018) and require approval by national authorities [3] and subsequently by the European Commission. The methodology and range of requirements for sensory evaluation are also defined by the International Olive Council (IOC) [4].

Figure 2.

IOC/EC-organoleptic criteria for olive oil classification [4].

Based on the panel test, the classification of the olive oil is done without prejudice to possible unauthorized material changes of the oil such as thermal posttreatment (adulteration), which cannot be detected in the panel test [5]. The aim of the panel test is the qualitative detection of negative attributes as well as positive attributes such as fruitiness (plus green-fruity or ripe-fruity), bitterness and pungency, and their quantification. The individual results of the panelists are statistically evaluated in order to obtain a sensory result that is valid and as objective as possible.

According to the currently valid criteria of the Regulation, samples that show a median for the negative attributes of “0” and also show a low fruitiness of only around 1.2 are already classified as “extra virgin.” Olive oils with a fruitiness intensity of more than 5 until 7 or 8 receive the same classification. In the case of sensory defects, a distinction is also made according to the intensity of the defects. If the median for a sensory defect is between 2.5 and 3.4 in intensity, the oil still belongs to the VOO category. But if it is a rancid defect, the oil becomes the grade lampante virgin olive oil (LVOO) in a couple of weeks or months. Generally, the consumer cannot tell from the name “virgin” that this oil has a defect such as fusty or rancid. The consumer thinks more of a lower quality than of a real defect or a bad taste without being aware of the risk of spoilage. According to the current food regulations in the EC, such foodstuffs have to be labeled accordingly. In our eyes, this is a weakness of the IOC Method No. T20, No. 14/2021 or Reg. (EEC) 2568/91 in its current version, that all olive oils classified as EVOO (on an annual average more than 1.2 million tons) belong to the highest quality segment in the sense of the regulation. EVOO is not a consumer product such as pasta, milk, or potatoes; it is a food ingredient and can in many ways turn cold, hot, or warm dishes into a delicious (and nutritious) experience or even spoil in case of a sensory error. Due to its unique organoleptic properties, it requires a more objective overall assessment, including differentiation in quality that is more recognizable to the consumer, in addition to its classification.

1.2 The trade needs a reliable benchmark for determining quality in the EVOO range

An adequate approach in order to achieve more differentiation in the category of EVOO, it was found in olive oil competitions organized mainly for premium olive oils. These competitions are not subject to any official regulation but are initiatives of national associations and organizers such as the IOC for the Mario Solinas Competition [6]. In the new test sheet for this competition, the parameter harmony has to be evaluated three times (olfactive, retronasal/gustatory, and global). With all due respect to olive oil competitions, it should be noted that the IOC holds a demanding annual competition for practically less than 2% of the EVOO produced worldwide. In these kinds of competitions, the producers are awarded with gold and silver medals, certificates, and recommendations. The result is valuable top-quality oils, tasty delicacies with a high content of healthy fatty substances [7]. But because not all olives of a producer can be picked in one day and because nature does not wait for olives to ripen continuously, in most cases, only smaller quantities of these high-value oils are available to about 15–20% of the somewhat better-off consumers. These awards are only given for exceptional commitment on the part of the producers, which work with extraordinary engagement down to the last detail. Accidentally, for the remaining rest of 98% (!) of the EVOO, no qualitative distinction is foreseen although even these oils have different, more or less characteristic flavors.

Unfortunately, the consumer’s knowledge of olive oil is not very common. Generally the consumer is unable to differentiate between terms such as varieties [8], cold-extracted, virgin or extra virgin, acid values. This is exploited by the trade in many countries and tolerated or supported by the legislator. Below the top qualities, there is no differentiation any more apart from mainly emotional arguments. Especially in this more affordable but very important mass market segment—which means for 80% of the consumer—a better differentiation is needed. It would help more consumers to gain confidence in a somewhat more expensive but recommendable oil.

The trade is dominated by price competition that often ignores quality aspects. For example, the 2015 IGO study [9] showed that out of 70 rather cheap samples from 15 different EU countries intentionally labeled as Extra Virgin, only 41.4% (29/70) could be confirmed as EVOO. 58.6% (41/70) had to be downgraded to the VOO category. The origin of the samples was reported as 58% EU blend, 23% Spanish blend, and 9% Italian blend.

Unlike food from certain countries such as honey or wine, olive oils from one country can be blended with oils from other countries within the EU and marketed as EU-Blends. The publication “EU-Blend” on the label is obligatory in such cases as well as all other origins from EVOO. The consumer must pay close attention to labels, including the brand name, as it is now mandatory to provide information on the label about the actual origin of the oil. Despite the wealth of information, many consumers lose their bearings and trust their personal shopping source more.

Regardless of this fact, we still assume that a not insignificant percentage of the oils sold worldwide as EVOO actually belong more to the VOO category due to sensory deficiencies. Some manufacturing companies simply refer to this type of EVOO as “borderline” EVOO. A practice that unfortunately cannot be ruled out is that olive oils with slight sensory defects are blended with extra virgin olive oils in such a way that the defects are very difficult to detect in a panel test. This means that for this type of EVOO in different panel tests (PT) different results such as VOO or EVOO can arise. The unofficial trade-declaration “borderline” depends on the requests of local stakeholders and the willingness of some suppliers, especially in those countries where the food control for olive oil is not yet so developed.


2. Material and methods

2.1 The panel test and the additional criteria harmony (QHV)

The German Olive Oil Panel (DOP), established in 1999 as a “virtual” panel [10] with the approval and support of the IOC, addressed the issue of different qualities within the EVOO category. The DOP was recognized by the IOC from 2001 to 2005 [11]. Since 2007, the DOP has been accredited according to EN ISO/IEC 17025 [3]. From 2011 to 2021, it is recognized by the German authorities, the European Commission, and the IOC [12].

The IOC has defined several guidelines and instructions for organoleptic assessment, which are continuously adapted. They include methodological aspects such as the necessary number of tasters (8–12), the basic vocabulary, the use of the profile sheet, test glasses, booth, etc. All details are described in depth in the IOC standards T20 No.14/2021 [4] and Reg. (EC) 2568/91 in their current version [1].

As mentioned in Chapter 1.2 of the introduction, the Panel test (PT) result in the European Union and third countries is only used to classify whether the oil is “extra virgin,” “virgin” (“ordinary”), or “lampante.” This study is concentrating on those samples only which gained the classification extra virgin.

The idea to extend the official sensory evaluation of olive oil was developed in the DOP by the panel leader Dieter Oberg already in 2003 in order to further differentiate the quality within the highest category “extra virgin.” For this purpose, it was necessary to extend the sensory test and as a consequence as well the profile sheet. A further parameter “harmony” was added at the end of the sheet analogous to the testing in many olive oils competitions. The official criteria defects, fruitiness, bitterness, and pungency remain unchanged. The tester follows the Reg. of EC/IOC for the result for the classification. But then it has to be decided for one additional but very important parameter “harmony” (QHV) in the same session.

The new QHV method [13] shows a mark in the middle of the additional line on the profile sheet (Figures 3 and 4), which indicates the mark “5” to the taster. Around this mark is a standard quality in the sense of an average quality or the cheapest offer often found in German supermarkets and discounters. A quality without sensory defects, but with a decent average in terms of character, flavor, or pleasant persistence, for example. Only 15–30% of the EVOO in the world reach values of more than 5.5 in the harmony scale. Values of more than 7 are only achieved by qualities, which are in a range of premium products. On the left side from the value “5” between 3.5 and 4.5, one finds oils with a sensory profile, which is “not sufficient” until “bad”—depending on if a panel did not decide for a median of defect. Many of the so-called borderline oils are further left around 2.8–3.8. Oils with a recognizable sensory defect are only rated around 3 and, depending on the intensity of the defect, even lower or 0. Finally, it is the PSV who can along the results of the panel test decide if a median for a defect is reached and then will set the factor harmony to “0.” In the training of tasters, the new criterion of harmony attempts to distinguish the fruitiness of an oil not only as present or absent, ripe or green. Now, for example, the differences between the olfactory impression (clean, clear, or less) and the subsequent taste impression (harmonious or strange, unexpectedly good in the sense of the relevant criteria or not) are additionally included in the quantified result for harmony. The tasters are asked as well to recognize particular aromas in olive oils. Aromas appear to the taster as the scent of a large bouquet of flowers or as clearly recognizable individual aromas of certain leaves, fruits, vegetables, or spices. Beyond this, the persistence and mouthfeel of the sensory impression create an overall impression in the taster, which is then translated numerically. This requires a special training of the tasters, as they are not limited any more to the official criteria such as fruity-bitter-pungent but can recognize additional sensory characteristic aspects of an oil, similar to wine. There are more than 500 olive varieties [8] grown in different ways in more than 20 countries. The goal is to produce oils with a certain sensory profile, even below the premium class. Only the additional criteria of harmony can fulfill this ambition.

Figure 3.

Excerpt from the profile sheet with additional line for harmony evaluation.

Figure 4.

Rough division of the red curve (enlarged) of Figure 3.

2.2 Methodology and practice

The official methodology for determining the QHV value includes four steps, which are described below and can be trained and performed using the feature-benefit formula in Figure 5. The feature-benefit diagram is a path on the way to the decision for a certain value for the taster’s QHV. The taster is referred to all four additional sensory characteristics (A–D) to be evaluated, can roughly tick the differently strong or less strong expression of the individual criteria, and thus arrive at a quantified overall result, which will be sent to the PSV.

  • A. Relation between olfactory impressions (odor) and gustatory impressions (taste): The first impression of the fruitiness via nose is the basic for purity and diversity of elements, which includes already the intensity. It feeds expectations for a similar retronasal impression. The second impression via palate (retronasal) can match the impression (plus/minus) or the taster has an unexpected impression with positive or negative olfactive elements.

  • B. Degree of purity and harmony/balance of the positive attributes (fruity, bitter, pungent):

    This balance increases if at the end bitterness and pungency are in a balanced relation to the fruitiness—preferably with a long persistency. Less balance means if bitterness or pungency is too dominant, and the positive impression of the fruitiness is more or less disturbed. The decision for the intensity of bitterness and/or pungency needs time.

  • C. Diversity, purity, and intensity of aromas and the harmony/balance between them:

    A sample can offer more positively a diversity of aromas in different intensities or just one single aroma—also in a lower intensity. A sample gives more negatively the impression of not clearly to defined aromas and/or aromas, which have not a perfect purity or not clear to defined aromas. Some aromas can be detected retronasal only.

  • D. Complexity of flavor, persistency, and texture of the positive impression:

    Complexity increases with the number/intensities of aromas and the flavor.

    A long and pleasant persistency of the flavor is positive.

    A more long texture is more positive than a short texture.

Figure 5.

Feature/benefit chart as an aid to getting started with the decision way for the additional QHV.

A rough description of an example: The tester decides for A with +, for B with +, for C with -, for D with ±. In the “Quantification” column of this theoretical sample, the tester first might decide mentally on the range “around 5” and then his final score 4.8. He enters this result on the profile sheet and passes it on to the PSV. Admittedly, a tester’s decision for a QHV quality “not sufficient, “upper standard,“ or “very good“ is as exact as a decision for the intensity of fruitiness or a defect. Ultimately, homogeneity in a panel for all attributes must be intensively practiced for a non-scaled line. Since so-called “outliers” can be eliminated by the PSV (see QHV methodology), the QHV evaluation with the median is as accurate as the official panel test. All the factors to be evaluated are well known to the international olive oil experts and tasters. Only the aroma designations may differ from tester to tester and from country to country, because not all aromas are common to every tester. Regardless, however, an individual aroma or aroma bouquet can be recognized by the tester in each country, as well as the evaluation of clarity and flavor. But even better, if the tasters stay longer in the panel, the continuous training and practice allow the summary of all mentioned criteria on one additional line (Figures 3 and 4) at the end of the official profile sheet. This means that the taster makes his evaluation in one operation first for the classification according to Reg. (EEC) 2568/91 in its current version (or the corresponding IOC standard) and then finally his decision for the value for the QHV (method DOP-2007-2).

The idea of this additional parameter harmony is to assign oils with the classification EVOO to additionally defined quality groups (Figure 6). This additional quality criterion is not regulated by law. However, the trade now has the possibility to select oils according to the requirements of the market in terms of price and quality.

Figure 6.

Definition of QHV quality levels for the different grades of EVOO with the method DOP-2007-2.

The unofficial assessment of QHV in the panel test should not be mandatory, but it should be an important option for the trade. Basically, the quality of an olive oil does not remain constant, but deteriorates slightly over the course of 18 months due to decreasing fruitiness and freshness. This and the fact that in the mass market new batches have to be compiled again and again during the year due to the large quantities require constant sensory control also on the basis of specifications from the trade. These specifications must not be utopian, but must be based on realistic values depending on the season.

The QHV methodology also includes the following guidelines [13]:

  • The valid median must have a robust coefficient of variation (CVr) below 10%.

  • Single results that exceed from the median by 1.5 or more have to be eliminated by the PSV. In case of a panel with eight tasters, only at least six from eight tasters need to have a valid result for the median of the QHV.

  • Suggestion of including the control of the Z-Score for the QHV in connection with the results of the PT for every taster.

  • The PSV is as well able to moderate single results of the QHV only.

  • In case a valid median of a defect is reached, the harmony value is set to zero (0) by the PSV.

  • The repeatability


3. Results and discussion

3.1 Global experiences of the previous 10 years

The application of this new criterion in sensory analysis since 2011 has led to a clearly recognizable improvement in the quality of olive oils on the German-speaking market as the figures from the IGO/DOP do prove. Every year, the DOP tests about 1000 samples according to this scheme, including harmony. Figure 7 illustrates that at the beginning in 2011, only 26% of the EVOO were rated >5.0–10 on the scale (from “higher standard” to “excellent”). By 2020, this figure had already risen to 75.6%. A measurable success for quality and thus for consumer protection. The trend from 2013 to 2020 in particular shows the remarkable way with a significant decrease in very poor qualities (QHV between 3.1 and 4.4) and also in the range of 4.5–5.0 (“lower standard”). The standard quality originally ranged from 4.5 to 5.4, but since more than 50% of all samples were in this segment, the standard quality was divided into lower (4.5–5.0) and upper standard (5.1–5.4). As a result, traders with their supporters focused only on the upper standard quality. The columns also show a remarkable increase in the range of 5.5–6.4 (QHV “good quality”) for the first wave of 2017, which seems remarkable as 2017 was a difficult year in terms of harvest in different producing countries.

Figure 7.

QHV results 2011–.2021(%) in Germany (source: IGO/DOP), n = 7500, results 2021 preliminary).

The QHV value is still unofficial and not part of the regulation, but it is firmly established in practice in German-speaking countries and is slowly gaining more and more acceptance among other importing and supporting companies. In the first years, the introduction process of the QHV was somewhat tough. Since 2011, the method has been presented to the professional public in further workshops and congresses [14, 15, 16] and backed up with initial figures. In countries with strong trade groups such as Germany, Austria, Switzerland, and others, the trade began to take an interest in the QHV, as media such as TV and the press—partly justified—were constantly looking for points of attack to devalue the olive oil quality at supermarket chains and discounters. The Information Office Olive Oil [17] in Germany (IGO) has therefore organized seminars at almost all relevant food companies since 2005, in which the QHV was explained as an important additional parameter. In the first years, the trade was content with at least reaching the level of >4.5 (standard quality) on the QHV scale. After a few years, the next level followed with 5.0—5.4 (upper standard). This was certainly due to the fact that the national control medium Stiftung Warentest considered the QHV as a co-decisive criterion in their comparative tests for the quality of an olive oil. This has also led to interest in this type of assessment on the part of bottlers, traders, and producers. At the request of the trade, introductory seminars were also held in the producer countries by the IGO. This led to further quality improvements in the trade, as now the quality became measurable with the help of the QHV method, which has also been accredited by the official German inspection body (DAkkS) since 2015. Now the trade is able to demand specified sensory quality requirements (intensities of fruity, bitter, spicy plus QHV) from its suppliers. However, due to the annually fluctuating characteristics of olive oils and the natural decrease of the individual intensities, the requirements have to be redefined every year or adapted to the annual rhythm by neutral experts.

Of course, thought was given to including the QHV on the label. However, for various reasons, this was not done and the responsibility was left to the trade. On the one hand, the label for EVOO is already very extensive due to numerous legal requirements. Since the QHV would entail an additional need for explanation for the consumer and it is also only used in a few countries, this idea had to be abandoned for the time being.

But in addition the type of fruitiness—green, green/ripe, or ripe fruitiness—became also part of the EC/IOC regulation in the framework of the panel test. Our investigations showed that these differences also had an impact on the assessment of the QHV. The graphic (Figure 8) shows an example from Greek oils in 2018: EVOO with green flavor received QHV scores in the range of 5.6–6.4 (very good) due to aroma richness and more intense fruitiness. For oils with green and ripe taste, i.e., from fruits with advanced ripeness, most QHV scores were between 5.1 and 6.4 (upper standard to very good). Oils with a more mature taste from ripe harvested fruits mostly reached QHV values of 4.5–5.4 (standard), partly because the fruit intensity is milder and the aromas are sweeter. In the latter EVOO, the polyphenol values are already significantly lower, which, among other parameters, also affects the stability of the oil. Due to natural conditions—ripening is a continuous process—harvesting times have been moved forward somewhat in some countries to increase the proportion of green or green/ripe olives. This is also in order to gain more green aromas, a higher nutritional value, and as a consequence, a slightly higher QHV value.

Figure 8.

Type of fruitiness and relevance for the QHV, grün = green; grün-reif = green-ripe; reif = ripe, source: 2018, n = 157 Greek samples, IGO [10].

3.2 Experiences from production countries for fruitiness and QHV

The effect of the QHV also opens the consumer’s senses for special characteristics of blended and country-specific oils—and that also for more affordable oils in the so-called mass market. To this end, we have broken down certain parts of the DOP test results of the last 7 years country by country to show differences and improvements. *The reader may pay attention to the fact that the calibration of the intensity of fruitiness in the DOP panel has changed 2021 to a slightly higher level. This step was initiated and practiced by a modified method in the framework of an IOC workshop and started in year 2021, but the process for the DOP panel has not yet been finalized.

Spain is the largest producing country in the world with an average of 1.2–1.4 Mio t. But only around 50% of this quantity is officially EVOO [18]. In addition, in the 2016/17 campaign, there was a big change in the development of fruitiness in Spain (Figures 9a and b). With an earlier harvest start since 2016 for the important varieties Picual and Hojiblanca, it became possible to bottle EVOO with at least green/ripe fruitiness even after 12 months for the mass market. This resulted in average fruit intensities of 4.1–5.0 (IOC/EC method) also in the second half of the year instead of only 3.5–4.0 as in previous years. This was also expressed in a QHV value that was more than 50% in the range of 5.5–6.4 (good) from 2018 to 2020. The graphs (Figures 9a and b) also show that the significant calibration correction for fruitiness has practically no influence on the evaluation of the QHV. Most of the samples consist of different mixtures of the Picual and Hojiblanca varieties and show a stable continuity of quality thanks to skillful blending.

Figure 9.

(9a) Fruitiness rating Spain, 2015–2021 (%), n = 65–265, (9b) QHV rating Spain, 2015–2021 (%), n = 65–265. Source: IGO/DOP.

Italy is home to a wide range of olive varieties with very different aroma profiles. In addition to individual other varieties, Coratina, Ogliarola, Arbosana, Carolea from the southern regions of Puglia and Calabria are mainly used in rather affordable oils due to sufficient quantities. These varieties already had a high QHV level since 2015 with values between 5.5 and 7.4 (good to very good) and were able to maintain this quality over the 5 years as far as climatic conditions allowed. This also shows a very stable QHV level over the entire period (Figures 10a and b).

Figure 10.

(10a) Fruitiness rating Italy, −2015-2021 (%), n = 50–76, (10b) QHV rating Italy, 2015–2021, (%) n = 50–76. Source: IGO/DOP.

In contrast to the above named countries, Greece, the third largest producing country, is characterized by many smaller farmers. In recent years, small cooperatives have been established to pool more knowledge about the harvest, quality, and what is happening in the markets. Throughout Greece, Koroneiki is the most important variety, accounting for 70% of the fruits grown. However, the variety can grow very differently due to climatic and soil differences between the north, the Peloponnese, and the island of Crete. The more the farmers work according to a certain predetermined strategy, the more consistent and better the quality will be. It can be seen that the intensity of fruitiness has increased significantly since 2016 to around 5.0 (year 2021 is different because of the new calibration). This was accompanied by a yearly increase in QHV up to the 5.5–6.4 level (good) or at least to the 5.1–5.4 level (upper standard), while QHV scores below this level continuously decreased (Figures 11a and b).

Figure 11.

(11a) Fruitiness rating Greece, 2015–2021(%) n = 95–166, (11b) QHV rating Greece, 2015–2021 (%), n = 95–166. Source: IGO/DOP.

EU Blends (EVOO from different EU producing countries, n = 130–363) also show a clear change in quality after 2015. The intensity of fruitiness (Figure 12a) increased continuously from 3.5–4.0 to 4.1–4.5 over the last 5 years. With the higher intensity, the character of the fruitiness also changed. Instead of predominantly ripe fruitiness as in 2015 and earlier, more oil was obtained from green to green-ripe olives, which in turn brought more intense flavors and thus also had a positive effect on the QHV (Figure 12b). While the QHV value 5.1–5.4 (upper standard) remained constant at a level of just over 30%, the value 5.5–6.4 (good) practically doubled from 16.2% to 35.4%.

Figure 12.

(12a) Fruitiness rating EU blend 2015–2021, (%), (12b) QHV rating EU blend 2015–2021 (%). Source: IGO/DOP.

Correspondingly, the value 4.5–5.0 (lower standard) dropped from 34.1–18%. EU blends are often the “price entry quality” for many nationally active traders.

The origin from the yearly up to 1000 DOP samples is roughly 20% Greek oil, 10% Italian, 30% from Spain, and 40% EU Blend. The figures for 2021 are not yet complete. In connection with all the above results, equally excellent EVOO were tested, some of which also won prizes in international competitions. These results have not been broken down by country, but they have a negligible impact on the above results, as they only account for 5–7% of the total number of samples per year. Values above 8.5–9, even up to 10, are extremely rare. But as already mentioned: “The higher the quality, the lower the quantity available in the trade”—therefore only a few oils can reach this segment.

Samples from other countries such as Portugal, Tunisia, Turkey, Croatia, Slovenia, and Palestine were also evaluated, but the number of samples per country was not sufficient for serious statistics.


4. Conclusion

The results for the individual production countries, as well as for all samples together, undeniably show the way to a quality improvement over a long period of time that was hardly thought possible. This is true not only in German-speaking countries, where during the previous years around 1000 panel tests are conducted annually, but also for production and distribution of some international brands. Last but not least, it was the trade that took up the idea in order to get olive oil out of the headlines of the negative press. After all, olive oil was once in the top group of food products that drew attention to themselves through fraud and adulteration. But the figures on which this study is based speak primarily for Germany, Austria, and Switzerland. In these countries, the control policy of the trade often still goes far beyond the requirements of the government or the European Commission. This also applies to the sensory analysis of olive oil taste, a decisive criterion for the consumer.

With the QHV, the trade received an additional quality parameter that closes the gap between the best classification (EVOO) and measurable quality grades for this classification. The trade—in the meantime also instructed in the QHV method—works out a profile for its various olive oils with expert advisors and passes it on to the producers. These—as well QHV trained—receive thus specifications for the production or blending. This helps the trade to the same extent with the so-called “borderline problem” between the two grades EVOO and VOO. With EVOO there are good and bad ones, with VOO there are always a median of defect with intensities up to 3.5. The QHV would certify a bad EVOO a very low rating and thus inform the buyer accordingly. However, the results also show that it is possible to achieve a certain good quality level with the QHV even with supermarket and discount chains—i.e., with very large quantities. Whether to achieve “upper standard” or “very good” is up to the retailer in each country to decide. But thanks to QHV, the desired level is quantifiable.

The evidence gathered since the QHV presentation in September 2019 to the IOC Expert Group on Sensory Items held in Madrid does not indicate that the QHV method will be adopted globally. However, it may be introduced on a country-by-country basis or applied by nongovernmental bodies at the request of operators. It was found that in some olive oil producing countries, there is a kind of creeping path for improving the field of processing from agriculture via harvesting, malaxation [2] to extraction.

The QHV method was developed with a focus on the transparent presentation of the different qualities of the “extra virgin” grade of this exceptional product olive oil. Since 2011, attempts have been made to show the possibilities of the QHV to the IOC as well [13, 19] in order to start joint international trials that would enable its possible use in other countries. While the Commission in Brussels accepts or nationally tolerates some member countries’ own initiatives—especially against the background of consumer protection with simultaneous proper production—the seemingly unassailable IOC seems to be pursuing its own policy under the protective shield of the UN. The national and economic benefits of olive oil are of undisputed importance in the producing countries. But it should also be transparent in the importing countries and compatible with the qualitative and legal requirements of consumers in their countries.

The QHV provides security in the assessment of EVOO qualities, it creates measurable transparency in the field of marginal oils, it limits the possibilities of fraud and helps in the detection of adulteration. With the QHV, there are fewer complaints and more satisfied customers.



QHVQuantified Harmony Value
EVOOExtra Virgin Olive Oil
VOOVirgin Olive Oil
LVOOLampante Virgin Olive Oil
OOOlive Oil (Refined Olive Oil Plus EVOO)
PTPanel Test
IOCInternational Olive Council
DOPGerman Olive Oil Panel
PSVPanel Supervisor/Panel Leader


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Written By

Dietrich Oberg

Submitted: 20 December 2021 Reviewed: 01 February 2022 Published: 25 April 2022