Food Marketing & Technology - India June 2019 | Page 32

Processing
Fig. 5: Approximately 800 g hazelnuts
of characteristic features of the
sampling seem difficult. Problematic
during the sample preparation are
often the high content of sugars and
the vitamin content. An embrittlement
with liquid nitrogen seems therefore
unavoidable, in order to change the
breaking behavior of the hard candy
and to guarantee the temperature
stability of the vitamins.
Fig. 6: Hazelnuts after 30 seconds grinding in the grinding
vessel made of stainless steel
All this can also be carried out with
the Knife Mill PULVERISETTE 11. A
beforehand conducted embrittlement
in the stainless steel vessel, as well as
only a brief comminution of 20 seconds
at 5,000 rpm, create a finely distributed
powder without a too high application
of energy.
On the trail of mycotoxins
Mycotoxins as metabolites of mildew,
like aspergillus niger or aspergillus
flavus, present a health risk for the
consumer. But also the economic losses,
as well as the possible not identified
An embrittlement with
liquid nitrogen seems
therefore unavoidable,
in order to change the
breaking behavior of
the hard candy and to
guarantee the temperature
stability of the vitamins
Fig. 6: Hazelnuts after 30 seconds grinding in the grinding
vessel made of stainless steel
infestation and the associated spoilage
of the quality due to mildew is
enormous. Especially significant are
the so called aflatoxins, since they are
already carcinogenic in the slightest
amounts. Due to this reason, are the
det e ction limits in the range of a
few μ g/ kg. Especially prone to such
“mildew n e st s” are spices or nuts of
any kind. Based on the f or mation of
nest s in such material samples, the
representative sample preparation for
Food Marketing & Technology
32
June 2019
a laboratory sample r equires a relativel
y large sampl e size. That’s why dur
i ng the tests wit h the Knife Mill
PULVERISETTE 11 approximately 80
0 g hazelnuts were processed. Initially,
the interval mode of 3 x 5 seconds with
4,500 rpm was utilized, and th e n t he
entire sample was homogenized again
for 15 s e conds at 6 ,50 0 rpm.
* Holger Brecht is Sales Engineer with
Fritsch GmbH Milling + Sieving.