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Truffles in Processed Foods – Truly Valuable or Just Empty Praise?

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Truffles in Processed Foods – Truly Valuable or Just Empty Praise? Powered By Docstoc
					05.09.2013




Truffles in Processed Foods –
Truly Valuable or Just Empty Praise?

Report from a day in the lab


Truffles have been experiencing somewhat of a renaissance in the                                        Tuber magnatum
last several years; ever more processed foods are being sold with
the addition of truffles. Even discount shops are offering truffled
foods, mostly by delicatessens offering specialties for festive occa-
sions. Truffles are known to be one of the most expensive foods; the
Alba white truffle (Tuber magnatum), for example, can cost as much
as 6,000 Euros per kilogram. However, there is also a wide pallet of
inferior grades such as the Chinese black truffle (T. indicum), which
smell and taste less like a truffle, and cost much less (7% thereof)
                                                                                                        Choiromyces venosus
than the Alba or Périgord truffle (T. melanosporum). The use of infe-
rior truffles and falsely declared truffle products is not only a culi-
nary disappointment for consumers, but often, in fact, a criminal
case of consumer fraud and a lucrative business for the defrauders.
The authenticity of the declarations regarding truffles has seldom
been analyzed. However, strict monitoring of truffle products is nec-
essary. The actual analysis of truffles is not particularly difficult; a
microscopic investigation suffices in most cases. Therefore, be-
tween September 2012 und May 2013, ten truffle-labeled products                                         Tuber borchii
from supermarkets were put under the microscope. We wanted to
know whether the content as stated on the packaging was, indeed, in
the truffle product.

Truffle Trivia
The „Guidelines for Fungi and Fungal Products“ [3], published in 2008 by
the Federal Ministry of Food, Agriculture and Consumer Protection (Ger-
many), lists the following types of „truffles“ specified on food content la-                            Tuber melanosporum
bels:

Name as Specified                   Scientific Name                                  Market Price
on List of Ingredients                                                               (€ / kg) [2]
Burgundy Truffle                    Tuber uncinatum Chatin
                                    (also T. aestivum forma unina-
                                    tum)
Chinese (Black)                     Tuber indicum C. & M.                            60 – 200 for T.    Tuber indicum
Truffle                             (including T. himalayense                        indicum
                                    Zhang&Minter; T. sinense Tao &
                                    Liu)
Kalahari Truffle                    Terfezia pfeilli Hennings
Desert Truffle                      Terfezia leonis Tul.
                                    ((synonym T. arenaria (Moris)
                                    Trappe))
Périgord Truffle                    Tuber melanosporum Vitt.                         800 – 3,000
 ADRESSE Schaflandstraße 3/2 70736 Fellbach           E-MAIL Poststelle@cvuas.bwl.de                    Tuber aestivum
 TELEFON +49 711 3426 - 1234                          INTERNET www.cvua-stuttgart.de
 +49 711 3426 - 1727 (Diagnostik)                     ÖFFENTL. VERKEHRSMITTEL S-Bahn S2 und S3
 FAX +49 711 588176 +49 711 3426-1729 (Diagnostik)    Bus 60, 67 und 212 Haltestelle Fellbach Bahnhof
Seite 2 von 9




Name as Specified        Scientific Name                      Market Price
on List of Ingredients                                         (€ / kg) [2]
Piemont Truffle,         Tuber magnatum (Pico) Vitt.          1,500 – 6,000
White Piemont Truf-
fle
Black Truffle*           Tuber indicum C. & M. (including     60 – 200 for T.
(see also Chinese        T. himalayense Zhang&Minter;         indicum
Truffle)                 T. sinense Tao & Liu)
Summer Truffle           Tuber aestivum Vitt.                 400 – 600 for
                         (in a broader sense also in-         T. aestivum,
                         cludes T. bituminatum Berk &         80 – 150 for T.
                         Br., T. macrosporum Vitt., T.        mensentericum
                         mensentericum Vitt.)
White Truffle*           Choiromyces venosus (Fr.) Th.
                         Fr.
                         (Synonym: C. maeandriformis
                         Vitt.)
Winter Truffle           Tuber brumale Vitt                   400 – 600

* There are some differences in the designation of truffle species between
English and German. In the Guideline for Fungi and Fungal Products the
German named „Black truffle“ is exactly the same as the Chinese truffle,
whereas, in English, the Black truffle is understood to be the Périgord truf-
fle. Likewise, the German named “White truffle” is an inferior grade under-
ground fruit, while, in English, the “White truffle” is understood to be the
most expensive Alba truffle.

For truffle products on the market, the term „truffle“ refers predominantly to
the tuber species. The desert truffle (Terfezia) und Mäander truffle
(Choiromyces) have little in common with real truffles, other than the bulb-
ous (tuber) shaped, underground fruit forms; neither their aroma nor their
taste. In addition, all “non-real” truffles are poisonous when eaten raw.


There is no legal obligation in Germany for businesses that sell truffled
food to provide the scientific name of the truffle species used. Unlike in
Switzerland [4] and France [5], there is also no established minimum quanti-
ty of truffles that a product must contain in order to be labeled with such.
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Samples Analyzed and Microscopic Results
                                     Microscopic                  Characteristics of the
                                     Photo                        spores found for the type
                                                                  of truffle [2]
1      Product    Truffle ham                                     Round to ellipsoid; light
       Declared   Truffle                                         yellow to light brown;
       Spores     T. aestivum                                     loose-mesh, net-like,
       found                                                      irregular polygonal. The
                                                                  ornamentation can easily
                                                                  be seen in the methyl
                                                                  blue coloration.
                                                                  1-6, usually 4, spores per
                                                                  Ascus



                                       Ascus with 4 spores from
                                         T. aestivum, 400 x,
                                        dyed with methyl blue
2      Product    Liver paste with                                Ellipsoid; depending on
                  truffles                                        ripeness, light brown to
       Declared   Truffle                                         black, opaque; plump
       Spores     T. indicum                                      spikes whose tips are
       found                                                      often bent. Base of the
                                                                  spikes often wide and
                                                                  partially linked. When
                                                                  touched, sporadic, adja-
                                                                  cent spikes suggest a
                                                                  net pattern.
                                                                  (1) 2-4 (5), usually 4
                                                                  spores per Ascus
                                       Ascus with 3 spores from
                                          T. indicum, 1000 x
3      Product    Boiled ham with                                 See Product Nr. 1
                  truffles
       Declared   Truffle
       Spores     T. aestivum
       found




                                       Ascus with 4 spores from
                                          T. aestivum, 400 x
4      Product    Liverwurst with                                 Elongated ellipsoid; with
                  truffles                                        ripening, from light brown
       Declared   T. melanosporum                                 to black-brown; ripe
Seite 4 von 9




                                      Microscopic                     Characteristics of the
                                      Photo                           spores found for the type
                                                                      of truffle [2]
       Spores     T. melanosporum                                     opaque; short spikes
       found                                                          whose bases are partial-
                                                                      ly connected to one an-
                                                                      other, through which a
                                                                      fine, wavy surface design
                                                                      is created.
                                                                      1-4 (6), usually 3 (4)
                                                                      spores per Ascus



                                        Ascus with 4 spores from
                                        T. melanosporum, 400 x
5      Product    Truffle ravioli                                     Ellipsoid; light yellow to
       Declared   Truffle                                             light brown; narrow retic-
       Spores     T. borchii                                          ulated surface; mesh
       found                                                          size very constant for
                                                                      every single spore.
                                                                      1-4, usually 2-3 spores
                                                                      per Ascus




                                      Asci with 1 and 2 spores from
                                             T. borchii, 400 x
6      Product    Truffle cheese                                      See Product Nr. 1
       Declared   Truffle aroma
       Spores     T. aestivum
       found




                                      Ascus with 3 or 4 spores from
                                      T. aestivum, 400 x, SW Photo
7      Product    Truffle ham                                         See Product Nr. 2
       Declared   2 % Black Truffle
                  (Tuber indicum)
Seite 5 von 9




                                      Microscopic                  Characteristics of the
                                      Photo                        spores found for the type
                                                                   of truffle [2]
       Spores     T. indicum
       found




                                        Ascus with 3 spores from
                                           T. indicum, 1000 x
8      Product    Triangoloni with       No truffle spores seen
                  Porcini and Truf-
                  fles
       Declared   0.0006 % Tuber
                  magnatum Pico
       Spores
       found      None found
9      Product    Truffle bratwurst                                See Product Nr. 1
       Declared   Summer truffle
       Spores     T. aestivum
       found




                                        Ascus with 6 spores from
                                           T. aestivum, 400 x
10     Product    Truffle butter                                   See Product Nr. 2
       Declared   Truffle
       Spores     T. indicum
       found




                                        Ascus with 3 spores from
                                           T. indicum, 400 x
Seite 6 von 9




                                        Microscopic                       Characteristics of the
                                        Photo                             spores found for the type
                                                                          of truffle [2]
                   T. pseudohi-                                           Ellipsoid; light yellow to
                   malayense                                              dark and chestnut brown;
                                                                          slightly transparent, with
                                                                          spiky-net ornamentation,
                                                                          linked with each other at
                                                                          the base; mesh size very
                                                                          constant for every single
                                                                          spore.
                                                                          1-8, usually 4-6 spores
                                                                          per Ascus




                                          Asci with 6 or 7 spores from
                                         T. pseudohimalayense, 400 x


Surprisingly, in one sample of truffled ham (Sample 1), which was only
labeled as „truffle“, T. aestivum (summer truffle) was found. In another
truffled ham, with „2 % black truffle (T. indicum)“ (sample # 7) listed under
the ingredients, only the cheaper T. indicum, as listed in the „Guidlines for
Fungi and Fungal Products, “[3] was confirmed to be contained in the ham.
Nevertheless, the common understanding of „black truffle“ is often con-
fused with the significantly more expensive T. melanosporum (truffe
noire).
A truffled cheese (sample 6) from a cheese counter was labeled only with
„truffle aroma“; however, with the help of just a magnifying glass (10X), we
were able to recognize the typical peridien and gleba of truffles and, under
a microscope, a large number of spores from the T. aestivum. That such a
high quality product was labeled with an “inferior” grade gives the impres-
sion that the seller isn’t knowledgeable about truffles and possibly wanted
to prevent any possible fraud. In a truffled butter (sample #10), in addition
to T. indicum, there was also a similar number of exotic T. pseudohimala-
yense spores found. It is difficult to distinguish between the spores of T.
pseudohimalayense and those of the higher quality bianchetti (T. borchii)
Seite 7 von 9




truffle (T. borchii) using a microscope. However, an ascus of T. pseudo-
himalayense contains 1 – 8, usually 4 – 6 spores, whereas the asci of T.
borchii contain only 1 – 4, usually 2 – 3 spores [1, 2]. In addition, analyses
of the truffle pieces under magnification of 10X revealed that the T. pseu-
dohimalayense peridien are dark brown to black, whereas the T. borchii
has thin-walled, light peridien. The findings regarding T. pseudohimala-
yense are thus unambiguous. These truffles are seldom sold on the mar-
ket, and smell only faintly intensive, according to the literature. In addition
to spores of T. indicum, T. aestivum und Terfezia leptoderma, similar type
spores were found in a truffled liverwurst spread, which was only labeled
as containing the truffle T. aestivum [2].


According to the label on a sample of „Triangoloni“ (sample # 8), the noo-
dle product contained 0.0006% of the expensive Alba truffle (T. magna-
tum). Although it smelled strongly of truffles, we couldn’t spot any spores,
even after several samplings. The mention of the most expensive truffles
may raise the assumption for the consumer that he has purchased a high
quality product, even if a 250 g. package contains only 0.0015 truffles, an
actual market value of only 0.009 Euros. This labeling would not be per-
mitted in some European countries. In Switzerland, for example, a product
that contained less than 1 mass percent of truffles would not be allowed to
be labeled with special reference to its containment of truffles [4].


Summary
Although truffle fraud is generally widespread, it seems to occur fairly sel-
dom in the area of industrially manufactured, ready-made products, prob-
ably because of the easy verifiability. Many truffle products are only la-
beled with the non-specific „truffle“ designation, so that even the use of
inferior grades of truffles doesn’t constitute fraud. In our analyses the truf-
fle products containing labels with specific truffle species were, by and
large, correct. In order to prevent consumer deception via labeling that
also encompasses lesser-grade truffles, some countries - Switzerland, for
example, since 2008 - have prohibited the simple labeling of food products
as containing „truffle“, without specifying the species. A similar regulation
exists in France [5].


The situation with fresh food products is different, as shown in a current
report[2]. Restaurant proprietors, butchers and others who offer truffled
products, as well as consumers who buy truffles on the market, can easily
be tricked and defrauded, either because the retailers are dishonest, or
Seite 8 von 9




because the retailers themselves were deceived by the traders from whom
they purchased the truffles. It is easy to be cheated because one needs a
lot of experience to be able to recognize macroscopic differences among
truffles species. Investigations that provide information regarding the quali-
ty and correct labeling of truffles need to be urgently carried out. Consum-
ers should be protected in view of the huge profits that the swindlers can
gain, and the concomitant financial losses that the consumers thus incur.
In addition to the continued analysis of truffles in processed foods, our
laboratory will soon begin investigating fresh samples from markets, trad-
ers, restaurants and small truffle processing companies.


Literature and Comparative Material
[1] René Flamme: Chinesische Marktpilze und Pilzmärkte (2): Truffle.
Schweizerische Zeitschrift for Pilzkunde / Bulletin Suisse de Mycologie
(SZP/BSM) 2005 (6), 256-7


[2] René Flamme, Thomas Flammer, Peter Reil: Trufflen-Leitfaden zur
Analyse der im Handel vorkommenden Arten (2013). IHW-Verlag, Eching,
ISBN 978-3-930167-77-7


[3] Bundesministerium for Ernährung, Landwirtschaft und Verbraucher-
schutz: Leitsätze for Pilze und Pilzerzeugnisse (2008) (Federal Ministry of
Food, Agriculture and Consumer Protection: Guidelines for Fungi and
Fungal Products)


[4] Verordnung des EDI (des Eidgenössischen Departement des Innern)
über Speisepilze und Hefe (817.022.106) vom 23. November 2005 (Stand
am 1. April 2008)


[5] Décret n° 2012-129 du 30 janvier 2012 relatif à la mise sur le marché
des truffes et des denrées alimentaires en contenant


Peter Reil (Bösingen) und Dr. Jörg Rau (CVUA Stuttgart) have kindly pro-
vided the following material:
- authentic permanent mount of T. melanosporum, T. borchii, T. indicum,
T. brumale and several tubers of fresh T. borchii (Peter Reil)
- two tubers of T. aestivum in brine (Dr. Jörg Rau).
Seite 9 von 9




Photo credits
All photos of the truffle are from Antonio Rodríguez (with friendly permis-
sion), to be found at http://www.trufamania.com
All photos from microscopic specimens are from Dr. Pat Schreiter, CVUA
Stuttgart.


Author
Dr. Pat Schreiter, CVUA Stuttgart.

				
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Description: Truffles have been experiencing somewhat of a renaissance in the last several years; ever more processed foods are being sold with the addition of truffles. Even discount shops are offering truffled foods, mostly by delicatessens offering specialties for festive occasions. Truffles are known to be one of the most expensive foods; the Alba white truffle (Tuber magnatum), for example, can cost as much as 6,000 Euros per kilogram. However, there is also a wide pallet of inferior grades such as the Chinese black truffle (T. indicum), which smell and taste less like a truffle, and cost much less (7% thereof) than the Alba or Périgord truffle (T. melanosporum). The use of inferior truffles and falsely declared truffle products is not only a culinary disappointment for consumers, but often, in fact, a criminal case of consumer fraud and a lucrative business for the defrauders. The authenticity of the declarations regarding truffles has seldom been analyzed. However, strict monitoring of truffle products is necessary. The actual analysis of truffles is not particularly difficult; a microscopic investigation suffices in most cases. Therefore, between September 2012 und May 2013, ten truffle-labeled products from supermarkets were put under the microscope. We wanted to know whether the content as stated on the packaging was, indeed, in the truffle product.