November 2018 Punch PDF

ARTICLE
6. Mold control: The key challenge in corn storage is to effectively safeguard corn from mold growth
and preserve its quality throughout the storage period. Mold growth is a serious concern as it is one of the main
reasons for the deterioration of corn quality during storage. Corn is an excellent source of nutrients for mold
growth. Mold growth reduces the nutritional value of corn as the mold consumes the nutrients and decreases
the energy content in them. Mold also produce toxic metabolites known as mycotoxins which have an adverse
effect on the animals’ health and performance. Mycotoxin content in moldy corn would always be higher and
at the same time moldy corn is not suitable for feed production. Following are most important factors for mold
growth-
• Oxygen • Temperature • Substrate
• Moisture • Time
Moisture content and storage temperature
are two major factors affecting corn quality during
storage. Mold requires moisture to grow. Therefore,
corn with high moisture content stimulates rapid
germination of mold spores and its proliferation in
the corn. The optimal moisture level differs from one
feed mill to another, depending on parameters such
as storage temperature and duration. The corn
moisture level during storage in India can vary from
11% to 14%.
Storage temperature plays another critical role
in affecting the corn quality during storage. Mold
growth occurs within a broad temperature range
from freezing to 45°C. Generally, higher storage
temperatures encourage mold growth which
accelerates the deterioration of corn quality. Fusarium, Aspergillus and Penicillium are three common mold
species found in corn storage.
It is critical to also consider relative humidity (RH) in the silos during corn storage. When RH is low, the
air picks can pick up moisture from the corn surfaces as it passes through the corn mass. However, when RH
is high or closer to saturation (RH = 100%), corn can take up moisture from the air. Thus, increasing the corn
moisture content and making it more susceptible to mold growth.
Conclusion: It is insufficient just to have optimum storage conditions in the silos as it is also important to
treat the corn such that they are well protected from mold growth. The storage conditions can differ from time
to time, such as an increase in temperature in the afternoons or during summer seasons, or a rise in RH during
rainy days. These can all lead to accelerated mold growth.
Grain Treatment Program with the use of organic acids is a potential method to offer maximum protection
of the corn against mold growth. Blend of organic acids is a very effective mold inhibitor that has a considerable
inhibitory effect on the mold counts in treated corn samples. Corn with high moisture can be stored if treated
with blend of organic acids.
References: 1. Fink-Gremmels, J. Animal Feed Contamination: Effects on Livestock and Food Safety. UK:
Woodhead Publishing.
2. Zain, M.E. (2011). Impact of mycotoxins on humans and animals. Journal of Saudi Chemical Society. 15
(2): 129-144.
3. Rocha, M.E.B.D., Freire, F.D.C.O., Maia, F.E.F., Guedes, M.I.F. and Rondina, D. (2014). Mycotoxins and
their effects on human and animal health. 36 (1): 159 – 165.
4. All About Feed, http://www.allaboutfeed.net/Mycotoxins/Regulations/, accessed 8 June 2017.
5. European Commision (2006). Commision Recommendation of 17 August 2006 on the presence of
deoxynivalenol, zearalenone, ochratoxin A, T-2 and HT-2 and fumonisins in products intended for animal
feeding. Official Journal of the European Union.
6. Abrigo, D. and Ho, J. (2013). Is corn eating away your profit?. Asian Feed Magazine, July/August 2013
issue.
82 November, 2018