Preservatives are included in feed and raw materials to prevent the spoilage caused by microorganisms and, thanks to it, they preserve the nutritional value and maintain the physicochemical properties of the substrates.

Organic acids, such as propionic, are bacteriostatic and fungistatic compounds widely used to preserve feed whose efficacy lasts for less than 2 months. Formaldehyde has also been widely used to eliminate Salmonella from feeds and raw materials but has many side effects on animals and manipulators and has already been limited by several regulations globally. Lastly, cimenol ring is an active molcule from plant extracts with bactericidal and fungicidal activities that can preserve feed and whose efficacy lasts for at least 6 months.

OBJECTIVES

• To determine the capacity of cimenol ring to preserve ground corn and compound feed through the elimination of the microorganisms that usually contaminate these substrates.
• To compare the efficacy of the cimenol ring with preservatives based on organic acids and formaldehyde.

 EXPERIMENTAL DESIGN

The efficacy of the three preservative was evaluated 24 hours and 7 days after their application through analyzing the reduction of the presence of several microorganisms in two substrates, ground corn and compound feed.

MATERIALS AND METHODS

The sterilized substrates before the start of the trial were contaminated with two known concentrations of each microorganism: 10³ CFU/g (moderate contamination) and 10⁶ CFU/g (high contamination).

Preservatives

• Cimenol ring + citric acid: natural product (0.5 kg/t)
• Product 1: formaldehyde + propionic acid (2 l/t)
• Product 2: propionic acid + ammonia propionate + propandiol (1 l/t)

Microorganisms

• Aspergillus
• Clostridium
• coli
• Salmonella

The reduction of microorganisms was calculated for each product from the difference in colony forming units per gram (CFU/g) with a control substratum that was contaminated and received no preservative.

CFU/g evaluation was conducted three times for each substratum, microorganism, and contamination. Results show the averages of the three evaluations.

RESULTS

Cimenol ring obtained higher reductions against all the microorganisms, in all the substrates and against all the tested concentrations, whether at 24 hours or 7 days (see the tables below).

CONCLUSIONS

Cimenol ring proved to be a much more efficient preservative than others based on organic acids and formaldehyde, at a lower dose, since it eliminated more than 85% Aspergillus, more than 96% Clostridium, and more than 96% E. coli and Salmonella. Its efficacy at a low dose allows to reduce costs and increase benefits, which as a positive economic impact.

Besides, cimenol ring is a completely natural product whose effect lasts for long periods and is useful for long-term stored materials, it is not corrosive, nor dangerous for animals and/or manipulators, differently from organic acids and formaldehyde.

Cimenol ring with citric acid are marketed by Biovet S.A. under the name Alquermold® Natural, available in premix and liquid.