Food authentication

1 Post-doc and 2 PhD positions

Would you like to join our research group? Currently we are searching 1 post-doc and 2 PhD students for different research lines:

  • PhD on Food authenticity: find new analytical strategies to identify authentic foods and prevent food fraud. In this PhD, state-of-the art analytical determinations combined with data processing by chemometrics (fingerprinting/omics) will be applied.  See here text call and application procedure 

(c) alswart – Fotolia

  • PhD on Lipids in animal feeding: study ways of re-valorizing of fat by-products as animal feed ingredients and their effects on meat composition, quality and stability. This PhD is a part of a collaborative project with companies in which new feed ingredients are being developed. See here text call and application procedure
Baby chicken having a meal

© Ljupco Smokovski 2007

 

We are at the… Food Integrity 2017

food_integrity_logo-500We are at the Food Integrity Conference 2017, in Parma, Italy (May, 9-10th, 2017). We are presenting our latest results on our research on olive oil authentication within the Autenfood project (ACCIO-Generalitat de Catalunya/FEDER, INNOAPAT RIS3CAT Community), and on the Characterization and standardization of fat by-products used in feeds.

 

We are at the….CAC2016!

Aceite de olivaWe are at the CAC2016: Chemometrics in Analytical Chemistry, that is take place in Barcelona, June 6th-10th, 2016.

We have presented a part of our results on the detection of virgin olive oil adulteration with other vegetable oils. This study belongs to our reserach line on Food characterization and authentication. IMG_20160607_104510

We are at…. I Workshop INSA-UB

Workshop_anual_INSAThe Olive Oil Universe is a workshop organized at the Torribera Food Campus by researchers from INSA-UB. 

In this Workshop we will be presenting the results of our last project on Food authentication. The project (titled “Acylglycerol fingerprinting of olive oil for fraud prevention” and leaded by Stefania Vichi PhD and Alba Tres PhD) is a preliminary study to find analytical tools to detect olive oil adulteration with seed oils. It has been funded by the FRI-2013 program of the INSA-UB.

The aim of the FRI program is to foster young INSA-UB researchers and to promote the collaboration between different research groups of the Institute.

INSA

Searching tools towards avoiding fraud in Iberian Ham!

Within our research area on food authentication, we are conducting a research project to find new analytical tools to answer the question: Is it trully Bellota Iberian ham (from pigs fed acorns)? Food products with added-value are susceptible to fraud, so having tools to detect fraud reduces fraud possibilites increasing the protection of consumers.

This week, an article describing the firsts results of this project has been published:

Authentication of Iberian dry-cured ham: New approaches by polymorphic fingerprint and ultrahigh resolution mass spectrometry

Bayes L, Tres A, Vichi S, Calvet MT, Cuevas-Diarte MA, Codony R, Boatella J, Caixach J, Ueno, S, Guardiola F.
Food Control, 2016, 60: 370-377

DOI: 10.1016/j.foodcont.2015.07.047

The journal offers it for free until October 14th, 2015. Click here to get it!!

This work presents new approaches to detect food fraud. The work deals with the problem from a multidisciplinary point of view. Thus, several crystallographic and analytical methods rarely applied to food authentication were assayed. In addition, these techniques were combined with chemometrics, using in some cases the state-of-the-art chemometric strategy in food authentication, which relies on finding a pattern in the raw analytical signal characteristic of the authentic product (fingerprint).
As a model to assay these new techniques for food authentication, we used two categories of Iberian dry-cured ham (Cebo and Bellota). With this model, the differential scanning calorimetry (DSC) thermograms of the lipid fraction provided fingerprints able to discriminate between both categories. Several crystallographic techniques (synchrotron radiation and laboratory-scale X-ray diffraction, and thermo-optical polarized microscopy) were used to characterize the crystallization, transformation and melting processes recorded by the DSC thermograms. The triacylglycerol composition determined by ultrahigh resolution mass spectrometry (UHRMS) was also able to discriminate between both categories. Thus, these determinations, in combination with chemometrics, may prove extremely useful to authenticate many foods containing high to moderate amounts of lipids, such as foods of animal origin.

Hazelnuts: nutrition and health claims

foto catala Hazelnut is a product frequently consumed as part of our Mediterranean diet. Direct consumption is common, but hazelnuts are also consumed as food ingredient in a wide variety of products (chocolates, ice-creams, cocoa & hazelnut spreads, cakes, pastries and cookies, and even in meat products) or for cooking preparation (salads, gravies, etc.). This diversity of applications is due to their particular sensory properties, very appreciated by the consumer.  But it is also important to take into account its nutritive value, fact that justifies its consumption according to international recommendations and dietary guides. Hazelnut nutritional value must be focused first on its energetic value (about 120 kcal/20 grams portion), which is mainly due to the high fat % of this nut (50-65%). However, it is also remarkable its good supply of other nutrients, such as 6% carbohydrates and 14% proteins. A 20 grams portion also provides 1,6 grams of dietary fibre, and relevant amounts of some vitamins and mineral elements: 8% vitamin B1 RDA; 7% folic acid RDA; 10% magnesium RDA (RDA, recommended dietary allowances).

But we would like to focus the attention in the fat fraction of hazelnut, since it is a major component and supplies a high amount of some fatty acids that are relevant for human nutrition and health. Hazelnuts from Catalonia (one of the major producer regions in the world) show a mean value of 60% fat, being the main part unsaturated fatty acids. From the total fatty acid fraction, 78% are monounsaturated, 14% polyunsaturated and only 7,5% saturated. According to the EU regulations (1, 2), these fatty acid values allow stating some “nutrition” and “health” claims. Possible “nutrition claims” for these hazelnuts would be: 1) High monounsaturated fat; and 2) High unsaturated fat. Accordingly, possible “Health claims” would be: Replacing saturated fats with unsaturated fats in the diet contributes to the maintenance of normal blood cholesterol levels (monounsaturated and polyunsaturated fatty acids are unsaturated fats).

As for the other plant oils and fats, there is a certain variability affecting the % total fat in the hazelnuts, as well as its fatty acid composition. This variability is mainly depending on the productive factors. Several studies carried out by our research group show that the factors related to the geographical origin of hazelnut (environmental and growing conditions) have a significant effect on hazelnut fatty acid composition while the cultivar has much less effect (3, 4). In contrast, some other components of fat, such as alpha-tocopherol (vitamin E, 30-47 mg alpha-tocopherol/100 g oil) have little variability due to the cultivar or the geographical origin. Moreover, we found that the harvest year has a huge influence in almost all these composition factors.

grafic avellanes engThe figure below shows the fatty acid composition (Palmitic, Oleic and Linoleic acids) of 4 hazelnut cultivars (Tonda Romana, Pauetet, Gironell and Negret). It can be seen that those growing in a mountain area (Falset) show always a higher % oleic acid and lower % linoleic acid compared to those growing in the near to the sea (Reus),regardless to the cultivar. Mean value for % linoleic acid (including the four cultivars) was 9,8% in Falset and 17,2% in Reus. In contrast, no significant differences were found between the values of the four cultivars cultivated in the same geographical area.

By Prof Rafael Codony

LITERATURE

1-COMMISSION REGULATION (EU) No 116/2010 of 9 February 2010 modifying REGULATION (EC) No 1924/2006 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 20 December 2006 on nutrition and health claims made on foods.

2-COMMISSION REGULATION (EU) No 432/2012 of 16 May 2012 establishing a list of permitted health claims made on foods, other than those referring to the reduction of disease risk and to children’s development and health.

3-Parcerisa, J.; Boatella, J.; Codony, R.; Farran, A.; García, J.; López, A.; Rafecas, M.; Romero, A. Influence of variety and geographical origin on the lipid fraction of hazelnuts (Coryllus avellana L.) from Spain: I. Fatty acid composition . Food Chemistry 48, 411-414. 1993.

4-Parcerisa, J.; Boatella, J.; Codony, R.; Rafecas, M.; Castellote, A.; García, J.; López, A.; Romero, A. Comparison of fatty acid and Triacylglycerol compositions of different Hazelnut varieties (Corylus avellana L.) cultivated in Catalonia (Spain) . Journal of Agricultural and Food Chemistry  43, 13-16. 1995.

Oils or fats?

The term fat is a generic term used to describe any greasy substance that is not soluble in water. This includes a wide range of products, from edible oils, common in our kitchens, to lubricants for mechanical uses. From a nutritional point of view, this term must be used with care, since these two non-equivalent terms (oil, fat) are used to designate fatty substances in food and feed.

mantega fonentoliva parcialment solidThe term “fat” refers to the substances formed by 100% liposoluble materials (not water soluble materials) and that have a semi solid aspect at room temperature (20ºC), such as lard or cocoa butter. Instead, the term “oil” includes those materials which also are completely liposoluble, but are liquid at room temperature, such as olive oil or sunflower.

But it is clear that this concept is relative, since it depends on temperature. For instance, we all know that when we heat the lard in the pan, it melts and becomes liquid. In the same way,in winter in cold climates  olive oil completely or partially solidifies. This case of olive oil raises an interesting question: why olive oil is often partially solidified when cooled down? The explanation is that oils and fats are not homogeneous materials. Actually they are composed of more than 95% of what are called triglycerides (molecules that contain 3 fatty acids attached to a glycerol). But in an oil or fat there is a great variety of triglycerides, originated by the various combinations of the different fatty acids that are in the oil or fat. In a simplified way, we could say that olive oil has triglycerides containing 3 unsaturated fatty acids (such as oleic) but also triglycerides containing 1, 2 or even 3 saturated fatty acids (such as palmitic). The consequence is that the triglyceride with 3 oleic acids melts at lower temperature (or in other words, it is liquid at room temperature), while that with 3 palmitic acids melts at a higher temperature (in other words, it is semi solid at room temperature). In between there are many other combinations of fatty acids in triglycerides, each melting at a different temperature. This explains why at a certain temperature, an oil or fat can be partially liquid and partially solid. Thus, we could say that the liquid or solid aspect of an oil or fat depends on its composition in different triglycerides. This variable composition not only has an impact on the melting temperature, but also in its oxidability and nutritional value.

On the other hand, the minor fraction of oils and fats (between 1 and 5%) is usually named non-glyceridic or unsaponifiable. It contains nutritional compounds of interest, such as fat-soluble vitamins (A, D and E) and sterols (cholesterol in animal fats and oils, and various phytosterols in vegetable oils and fats). In virgin olive oil there also are some polyphenolic compounds that have shown antioxidant effects and preventive or modulating properties in atherosclerosis, diabetes and cancer among others. This has implied that the EU has authorized in its regulations (Regulation No 432/2012) a health claim for labeling or advertising of olive oils that contain polyphenols above a certain concentration (5 mg of hydroxytyrosol per 20 grams of oil).

By Rafael Codony, PhD

COMMISSION REGULATION (EU) No 432/2012 of 16 May 2012 establishing a list of permitted health claims made on foods, other than those referring to the reduction of disease risk and to children’s development and health. Official Journal of the European Union, L136/1.