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Revista Brasileira de Produtos Agroindustriais, Campina Grande, v.15, n.1, p.81-92, 2013 81 ISSN 1517-8595

EFFECTS OF FEED PROCESSING FOR THE REDUCTION OF

MICROBIOLOGICAL CONTAMINATION IN THE FINAL PRODUCT

Paulo Carteri Coradi1, Adílio Flauzino de Lacerda Filho

2, José Benício Paes Chaves

3,

Evandro de Castro Melo4

ABSTRACT

The objective of the present study is to survey the microbiological indexes and to evaluate the

effects of feed processing in the reduction of present contamination in raw materials and

feedstuffs of a feed mill unit with production capacity of 1,000 ton.day-1, located in the State of

Minas Gerais, at Southwest Brazil. In order to evaluate samples of products samples were

collected from different points of the equipment surfaces and along the flow of feed production.

The Aspergillus candidus (3.7x105), Penicillium duclauxii (4.6x105), the Clostridia perfringens

(1.6x105), Listeria monocytogenes (6.1x103) and Escherichia coli (2.4x103) were the

microbiological contamination most detected on the surface of equipments. Moreover, the

higher contamination indexes (100% of contaminated samples) occurred in the silos of

expedition and trucks of feed transport. Furthermore, during the feed production steps the

microbiological contamination decreased from 5.3x105 to 0.2x101 in the final product. The

microbiological contamination identified in the production flow characterized by the materials,

equipment, machinery used in formulating the feed. Positively, the processing of feed,

especially the pelletizing step, reduced microbiological contamination in the final products.

Keywords: corn, feed, soybean meal, and quality.

EFEITOS DO PROCESSAMENTO DA RAÇÃO NA REDUÇÃO DA CONTAMINAÇÃO

MICROBIOLÓGICA NO PRODUTO FINAL

RESUMO

Neste estudo o objetivo foi realizar um levantamento dos índices de contaminação

microbiológica e avaliar os efeitos das etapas de processamento da ração na redução da

contaminação presente nas matérias-prima e rações processadas de uma fábrica de ração, com

capacidade de produção de 1.000 ton.dia-1

,localizado no Estado de Minas Gerais, Sudoeste do

Brasil. Para a realização deste trabalho coletaram-se amostras de produtos nas superfícies dos

equipamentos e no fluxo de produção da ração. Aspergillus candidus (3.7x105), Penicillium

duclauxii (4.6x105), Clostridia perfringens (1.6x10

5), Listeria monocytogenes (6.1x10

3) e

Escherichia coli (2.4x103) foram os micro-organismos mais identificados na superfície dos

equipamentos. Além disso, os índices mais elevados de contaminação (100% de amostras

contaminadas) ocorreram nos silos de expedição e nos caminhões de transporte da ração.

Acrescenta-se que, durante as etapas de produção da ração, houve diminuição da contaminação

microbiológica de 5.3x105 para 0.2x10

1 no produto final. Ressalta-se que a contaminação

microbiológica identificada no fluxo de produção foi caracterizada pelo conjunto de materiais,

equipamentos e máquinas utilizados na formulação de ração. Positivamente, o processamento

das rações, especialmente a etapa de peletização, tem função importante na redução da

contaminação microbiológica dos produtos finais (0.2x101).

Palavras-chave: milho, ração, farelo de soja e qualidade.

Protocolo 14-2012-14 de 15/06/2012 1 Professor Adjunto I, Doutor, Universidade Federal de Mato Grosso do Sul (UFMS), Campus de Chapadão do Sul,

Chapadão do Sul, MS, [email protected], (67) 3562-6300 2 Professor Associado II, Doutor, Universidade Federal de Viçosa (UFV), Departamento de Engenharia Agrícola, Viçosa,

MG, [email protected], (31) 3899-1872. 3 Professor Titular, Doutor, Universidade Federal de Viçosa (UFV), Departamento de Tecnologia de Alimentos, Viçosa, MG,

[email protected], (31) 3899-1758. 4 Professor Associado I, Doutor, Universidade Federal de Viçosa (UFV), Departamento de Engenharia Agrícola, Viçosa,

MG, [email protected], (31) 3899-1873.

mailto:[email protected]




82 Effects of the feed processing in the reduction of the microbiological contamination on the final product Coradi et al.

Revista Brasileira de Produtos Agroindustriais, Campina Grande, v.15, n.1, p.81-92, 2013

INTRODUCTION

Brazilian agribusinesses had representativeness

in the international trade, with 35% of chicken

production. In the international context Brazil is

the third largest producer of foods balanced for

animals, behind only the United States and

China, and the largest producers at Latin

America with 50% of the production

(Sindirações, 2008). Today for businesses to

survive on the market competition, they must

differentiate themselves by pursuing better

alternatives. The application of quality

improvement concepts allows businesses to

better participate in the dispute for market

share, since both markets and clients are

demanding higher standards for products and

services, stimulating the continuous evolution

of processes (Henson et al., 1999; Unnevehr, et

al., 2000; Maldonado et al; 2005; Coradi et al.,

2010b). Cereal grains and associated by-

products constitute important sources of energy

and protein for all classes of farm livestock,

however, when cereal grains and animal feed

are colonized by fungi and bacteria there is a

significant mycotoxins production risk,

affecting the animals and humans productivity.

Many species of Fusarium, Aspergillus,

Penicillium and Alternaria are not only

recognized plant pathogens but are also sources

of the important mycotoxins of concern in

animal and human health (Tabib, 1981; Henson

et al., 1999; Unnevehr, et al., 2000; Maldonado

et al; 2005). Bacterial contamination of animal

feed is another important point and it must be

controlled, as infection and colonization of

livestock and poultry with these pathogens can

be transmitted later to humans causing human

food-borne illness (Hinton, 2004; Roberts et al.,

1995). Animal feed is thus an important early

link in the “farm-to-fork model” chain of food

safety. Two anaerobic Clostridia sp. are of

major concern in feed, Cl. perfringens and Cl.

botulinum. Cl. perfringens has been linked to

bloating (gastric dilatation) in primates and

necrotic enteritis in poultry (Annett et al.,

2002). Listeria sp. is an invasive

microorganism that has been reported to cause

abortions, encephalitis and septicemia in

ruminants (Veldman, 1995; Annett et al., 2002).

E. coli strains are normal components of animal

and human intestinal microflora, and thus serve

as an indicator of fecal contamination in feed

(Geornaras et al., 2001). Salmonella sp. is

estimated to be the third most common cause of

human food borne illness (Curtain, 1984;

Tauxe, 2002). Despite the importance of plant-

protein as a main ingredient in animal feed,

there are very few studies in the literature that

focus on the prevalence and risk factors for

microbiological contamination of plant protein

in animal feed. Previous studies have verified

the mycobiota formation in final poultry feed

(Diener et al., 1987; Rotter et al., 1996;

Weidenborner, 2001; Eriksen & Pettersson,

2004; Coradi et al., 2011c). Most poultry feeds

are prone to fungal and bacterial growth during

different stages of the manufacturing process.

Thus, the study had as objective to survey and

quantifies the distribution of the

microbiological contamination indexes presents

in the feed mill and to verify the effects of the

processing system in the reduction of the

contamination in the final feed.

MATERIAL AND METHODS

Characterization of the feed processing unit

The experiment was conducted at a poultry feed

facility with capacity of production of 1,000

ton.day-1

located at Minas Gerais State,

Southwest at Brazil. The feed mill includes a

parking area for grain trucks, and also a

weighing system of raw materials by automatic

scale systems. The unloading of bulk products

(corn and soybean meal) are performed in

separated hoppers, while a manual system is

utilized for individual units of sacked raw

materials. The grain pre-cleaning system

consists of an air machine and sieves with a

capacity of 60 ton.h-1

in which light impurities

are removed. The impurities and damaged

grains are separated in the sieves based on

different formats, according to the perforation

standards of the sieves and the quality standards

adopted by the industry. The grain drying is

performed in a continuous flow dryer with a

nominal capacity of 60 ton.h-1

. The product is

transported within the mill by bucket elevators,

belt conveyers and screw augers. Storage units

consist of metallic silos with capacities of 1,200

tons and 2,100 tons. On the corn storage there

are composts with silos of capacities of 200

tons each, and used during the highest harvest

point in the final drying of products. Soybean

meal is stored in cement and metallic silos with

capacities of 350 tons and 100 tons,

respectively. Micro ingredients, including

metionina, lysine, lime, salt, sodium

bicarbonate, premixes, vitamins, and rice,

wheat, and animals meals are stored in an

internal area of the mill. Weighing of these

ingredients is done manually and they are

Effects of the feed processing in the reduction of the microbiological contamination on the final product Coradi et al. 83


mixed in a pre-mixer machine. The ingredient

mixing system is composed of a pre-mixer,

mixers, and a hopper bin, with a capacity for

4,000 kg. The system is operated and controlled

automatically by a computer. Weighing and

addition of ingredients is done in a hopper for

receiving, doser and doser bins, oil (fat) tanks

and a weighing scale. The control system is

automatic and computerized for addition of the

following products: soybean meal, wheat meal,

corn germ, feather, visceral and meat meals and

visceral oils according to the specific feed

recipe. After weighing and the addition of the

ingredients, the products are ground

simultaneously. The grinding system is

composed of hammer mills with a rated power

of 128.0 kW. Pelletization is performed with

pelletizers presenting capacities of 25 tons,

operating at a temperature and pressure of 73ºC

and 75 KPa, respectively. After formation, the

pellets are cooled to remove excess moisture

and heat. The loading system of feed is in bulk,

utilizing hopper bins and storage silos with

capacities of 60 tons. Discharge is done directly

in bulk feed trucks. The entire product

transportation system in the feed mill is

continuous. The grains, soybean meal, and

other meals arrive at the feed mills by means of

bulk trucks. Wheat and rice meals, as well as

other micro ingredients such as premixes and

vitamins are transported to the mill in trucks

suited for transport of sacked feeds. The base

quantities of ingredients used to the poultry

feed formulation is presented in the Table 1.

Table 1. Percentage of ingredients used in the

feed formulation for poultry

Ingredients Quantities of products

(%)

Corn 64.387

Soybean meal 26.994

Animal meals 4.847

Soybean oil 1.554

Limestone 1.035

Salt 0.359

Methionine 0.206

Lysine 0.118

Vitamin-mineral 0.500

Total 100.00

Sampling of the products

In the equipments of weighing of macros and

micros ingredients, hopper, pre-cleaning,

drying, storage silos, auger conveyers, belt

conveyers, buckets elevators, mixer, milling,

pelletizer, cooler, silos of expedition, and truck

to transport of feed were collected swab

samples. The collected of samples was realized

with the passage sterile swab over an area of

100 m2 of equipment surface using the open

mold properly sanitized to demarcate the area.

Each equipment fourth samples were collected

and distributed in different points. After

sampling, the swab was put in a tube and

covered with solution, identified and

conditioned in a special box and sent to

microbiological analysis. A total of 252

samples were collected (88 samples in the flow

corn production, 60 samples in the flow

soybean meal production, and 108 samples in

the flow feed production). Samples of corn and

soybean meal were collected in the receiving

sector (unload truck). In total 70 trucks were

sampled, and in each truck was collected

approximately 15 kg of products distributed in

different points of the mass, and reduced it to 1

kg for analysis. In addition, samples of animal

meals (54 visceral samples, 51 feathers

samples, 57 bone samples, and 44 meat

samples) were collected in the truck unload,

during the running mill. Samples of 1 kg were

collected in the sectors of grinding (40

samples), mixing (40 samples), mash (40

samples), and pellet (40 samples) feed.

Water content

For determination of water content in animal

meals, and feed were performed the weighing

of the capsules, previously cleaned and dried in

an oven at 105 ºC for one hour and cooled in a

desiccator until room temperature. A sample of

5 g was weighed and placed in an oven

preheated to 103 ºC ± 2 ºC until constant weight

(4 hours). After this time, the container was

removed from the oven, cooled in a desiccator

until equilibrium with the ambient temperature,

and held the weight (Brasil, 1993). The water

content of corn (% w.b.) was determined by

indirect method, using the meter moisture

Geole (G-800) after being calibrated with the

official from the oven, set at 103 ºC ± 2 ºC for

24 h. Tests were performed with samples of 50

g in three replicates, according to

recommendations contained in Rule for Seed

Analysis (Brasil, 1992).

Microbiological analyses

The mains fungi of the genus Fusarium sp. (F.

moniliforme, and F. proliferatum) Aspergillus

sp. (A. candidus, and A. flavus) and Penicillium

sp. (P. duclauxii, and P. funiculosum) were



isolated, enumerated and identified. The

samples were diluted in 225 ml of distilled

water, sterilized for dilutions. In each one of the

dilutions, brackets of 0.1 ml were transferred to

Petri plates with the culture middle Ágar Pink

Dicloran of Cloranfenicol Bengala (APDCB)

(Taniwaki, 1996). The colonies grew in room

temperature at 28 ºC ± 1 ºC for 72 hours. After

the incubation period, counting of the colonies

(CFU.g-1) was done (Lacaz et al. 1991). The

fungi identifications were accomplished with a

base in the microscopic aspect of the colonies

with description of the colonies in half Ágar

Czapeck, Ágar Batata Dextrose and Ágar

Extract of Malt (Lacaz et al. 1991). Salmonella

sp. was analyses using the general method

described by the American Public Health

Association American Public Health

Association-APHA (Speck, 1984). The

methodology for sample preparation was the

same as described for the analysis of fungi. The

material was incubated at 370 ºC in a

bacteriological incubator for 18 hours as pre-

enrichment, for the initial isolation of

Salmonella sp. Aliquots of 1 ml pre-enriched

sample were inoculated in Muller Kauffmann

tetrathionate broth (TMK) and incubated at 370

ºC for 18 h for quantification.The black E. coli.

colonies were identified by E.C. tubes with gas

using agar plates and Eosin Methylene Blue-

EMB (35 ºC ± 1 ºC for 24 hours). For Listeria

monocytogenes analyses a serving of 25 grams

of sample was weighed and homogenized in

225 ml of LEB broth (Listeria Enrichment

Broth, UVM formulation, Oxoid) and incubated

at 30 ºC for 24 hours. The 0.1 ml of this

material was transferred into a tube containing

10 ml of Fraser Broth (Oxoid), which was

incubated at 37 ºC for 24 hours. The blackened

Fraser Broths were plated on agar Palcan and

Oxford (both Oxoid), and incubated at 37 ºC for

24 hours. The colonies of Listeria

monocytogenes were transferred to trypticase

soy agar plates supplemented with 0.6% yeast

extract (TSA-YE, both Oxoid) to verify its

purity. The count of Clostridium perfringens

was performed in culture medium base Broth

Trypcase Modified Soybeans-BTMS for one

gram of sample. After, 10 ml of the suspension

material were seeded in the BTMS. The plates

were incubated under anaerobic conditions for

20h at 35-37ºC. All the analysis was performed

in three replicates. The results were analyses by

frequency (%) of samples contaminated, and

the counting by the Colony Forming Units

(CFU.g-1) of bacteria and fungi were calculated

by the number of samples evaluated.

RESULTS AND DISCUSSION

The contamination of raw materials in the

production flow made the process even more

burdensome to industry. In general, fungi

promoted significant damage to feedstuffs, and

among the many important fungi for the poultry

industry are Fusarium sp., Aspergillus sp., and

Penicillium sp. growing prior during field and

after the during storage. These fungi species

affected the quality, altered the physical

conditions of the products and reduced the

nutritional values. However, the

microbiological contamination in the feed mill

often does not occur only by using materials of

low quality, but also by contamination present

on the equipments of the production flow, as

observed in the Tables 2, 3, and 4.

Table 2. Counts of fungi and bacteria species on the equipment surfaces of the feed mill

Types of fungi

and bacteria

Sectors of corn

production

Sectors of soybean

meal production

Sectors of feed

production

(CFU.g-1

) (CFU.g-1

) (CFU.g-1

)

Fusarium moniliforme 1.6x102 1.0x10

1 2.2x10

2

Fusarium proliferatum 1.4x103 1.1x10

1 3.6x10

1

Aspergillus flavus 2.5x104 1.6x10

2 2.8x10

3

Aspergillus candidus 3.7x105 1.7x10

2 4.1x10

4

Penicillium duclauxii 4.6x105 1.2x10

2 5.2x10

4

Penicillium funiculosum 6.2x104 1.4x10

2 3.7x10

4

Clostridia perfringens 1.6x105 2.2x10

3 2.7x10

3

Listeria monocytogenes 1.4x103 3.1x10

2 6.1x10

3

Escherichia coli 2.5x102 1.7x10

1 2.4x10

3

Salmonellas sp. 3.7x102 1.0x10

1 1.2x10

2



Table 3. Frequency of samples fungi contaminated in the flow production of the feed mill

Sampling

Frequencya (%)

F.

moniliforme

F.

proliferatum

A.

flavus

A.

candidus

P.

duclauxii

P.

funiculosum

Cornb

Buckets elevators 4 (33.3) 5 (41.7) 8 (66.7) 7 (58.3) 9 (75.0) 6 (50.0)

Auger conveyers 10 (50.0) 12 (60.0) 14 (70.0) 11 (55.0) 15 (75.0) 7 (35.0)

Belt conveyers 15 (62.5) 16 (66.7) 20 (83.3) 24 (100.0) 18 (75.0) 21 (87.5)

Weighing 4 (100.0) 4 (100.0) 4 (100.0) 4 (100.0) 4 (100.0) 4 (100.0)

Hopper 4 (100.0) 4 (100.0) 4 (100.0) 4 (100.0) 4 (100.0) 4 (100.0)

Pre-cleaning 4 (100.0) 4 (100.0) 4 (100.0) 4 (100.0) 4 (100.0) 4 (100.0)

Drying 1 (75.0) 1 (75.0) 3 (75.0) 3 (75.0) 2 (50.00 3 (75.0)

Storage silos 6 (37.5) 10 (62.5) 14 (87.5) 15 (93.7) 12 (75.0) 11 (68.7)

Soybean mealc


Auger conveyers 2 (12.5) 6 (37.5) 7 (43.7) 5 (31.2) 12 (75.0) 11 (68.7)

Belt conveyers 4 (33.3) 6 (50.0) 5 (41.7) 4 (33.3) 7 (58.3) 6 (50.0)

Weighing 1 (25.0) 1 (25.0) 1 (25.0) 1 (25.0) 2 (50.0) 2 (50.0)

Hopper 0 (0.0) 3 (75.0) 2 (50.0) 1 (25.0) 3 (75.0) 3 (75.0)

Storage silos 1 (25.0) 2 (50.0) 2 (50.0) 1 (25.0) 3 (75.0) 3 (75.0)

Feedd


Auger conveyers 2 (16.7) 4 (33.3) 5 (41.7) 4 (33.3) 7 (58.33) 8 (66.7)

Belt conveyers 2 (25.0) 3 (37.5) 4 (50.0) 6 (75.0) 8 (100.0) 8 (100.0)

Weighing 1 (25.0) 1 (25.0) 2 (50.0) 2 (50.0) 3 (75.0) 2 (50.0)

Grinding 1 (25.0) 1 (25.0) 3 (75.0) 1 (25.0) 3 (75.0) 3 (75.0)

Mixing 0 (0.0) 0 (0.0) 2 (50.0) 3 (75.0) 2 (50.0) 3 (75.0)

Pelletizing 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0) 1 (25.0) 0 (0.0)

Cooling 0 (0.0) 0 (0.0) 0 (0.0) 1 (25.0) 1 (25.0) 2 (50.0)

Expedition silos 4 (16.7) 8 (33.3) 15

(62.5)

17 (70.8) 20 (83.3) 18 (75.0)

Truck 5 (25.0) 4 (20.0) 8 (40.0) 12 (60.0) 16 (80.0) 15 (75.0) aPorcentage of samples in which each fungus and bacteria was present. bNumber of corn samples: total, n = 88; weighing, n = 4; hopper, n = 4; pre-cleaning, n = 4; drying, n = 4; storage silos, n = 16; auger conveyers, n = 20; belt conveyers, n = 24; and buckets elevators, n = 12. cNumber of soybean meal samples: total, n = 60; weighing, n = 4; hopper, n = 4; storage silos, n = 16; auger conveyers, n = 16; belt

conveyers, n = 12; and buckets elevators, n = 8. dNumber of feed samples: total, n = 108; auger conveyers, n = 12; belt conveyers, n = 8; buckets elevators, n = 8; weighing of macros, n = 4; grinding, n = 4, mixing of ingredients, n = 4; pelletizing, n = 4; cooling, n = 4; silos

expedition, n = 24; truck, n = 20.

Under these conditions was verified that

the contamination of the equipments

compromised the quality of other raw materials,

making the economic losses to the industry

even higher. Moreover, the cleaning, washing

and maintenance of the equipments influenced

in the quality of the production system, mainly

in the water content of the products, as well as

the temperature and relative humidity of the

ambient air (Coradi, 2010a). In the evaluation

observed that the fungi development in

environments with relative humidity greater

than 70%, optimal temperatures among 20 and

30ºC, and water content greater than 12%. The

high water content associated with high

temperature in the products interfered in the

operation of the equipments, and during the

time, residual products accumulated on the

surfaces them causing a big focus of

contamination. Tables 2 show the

contamination intensity on the surfaces of

equipments, the Aspergillus candidus (3.7x105)

and Penicillium duclauxii (4.6x105)

predominated among the fungi species, while

Clostridia perfringens (1.6x105), and Listeria

monocytogenes (6.1x103) were the most

observed among the bacteria species

.



Table 4. Frequency of samples bacteria contaminated in the flow production of the feed mill

Samples

Frequencya (%)

Cl.

perfringens

L.

monocytogenes

E.

coli

Salmonellas sp.

Cornb

Buckets elevators 7 (58.3) 5 (41.7) 8 (66.7) 3 (25.0)

Auger conveyers 10 (50.0) 8 (40.0) 9 (45.0) 6 (30.0)

Belt conveyers 22 (91.7) 22 (91.7) 20 (83.3) 8 (33.3)

Weighing 3 (75.0) 3 (75.0) 1 (25.0) 0 (0.0)

Hopper 4 (100.0) 1 (25.0) 0 (0.0) 1 (0.0)

Pre-cleaning 2 (75.0) 2 (50.0) 0 (0.0) 0 (0.0)

Drying 1 (25.0) 0 (0.0) 1 (25.0) 0 (0.0)

Storage silos 8 (50.0) 9 (56.2) 8 (50.0) 3 (18.7)

Soybean mealc


Auger conveyers 10 (62.5) 8 (50.0) 9 (56.2) 5 (31.2)

Belt conveyers 8 (66.7) 7 (58.3) 6 (50.0) 2 (16.7)

Weighing 1 (25.0) 1 (25.0) 0 (0.0) 0 (0.0)

Hopper 4 (100.0) 2 (50.0) 1 (25.0) 1 (25.0)

Storage silos 4 (100.0) 4 (100.0) 3 (75.0) 2 (50.0)

Feedd


Auger conveyers 9 (75.0) 8 (66.7) 10 (83.3) 6 (50.0)

Belt conveyers 7 (87.5) 6 (75.0) 6 (75.0) 4 (50.0)

Weighing 2 (75.0) 1 (25.0) 0 (0.0) 0 (0.0)

Grinding 2 (50.0) 0 (0.0) 0 (0.0) 0 (0.0)

Mixing 2 (50.0) 2 (50.0) 3 (75.0) 2 (50.0)

Pelletizing 0 (0.0) 1 (25.0) 1 (25.0) 0 (0.0)

Cooling 1 (25.0) 2 (50.0) 2 (50.0) 1 (25.0)

Expedition silos 12 (50.0) 13 (54.2) 14 (58.3) 12 (50.0)

Truck 10 (50.0) 9 (45.0) 11 (55.0) 9 (45.0) aPorcentage of samples in which each fungus and bacteria was present. bNumber of corn samples: total, n = 88; weighing, n =

4; hopper, n = 4; pre-cleaning, n = 4; drying, n = 4; storage silos, n = 16; auger conveyers, n = 20; belt conveyers, n = 24; and

buckets elevators, n = 12. cNumber of soybean meal samples: total, n = 60; weighing, n = 4; hopper, n = 4; storage silos, n =

16; auger conveyers, n = 16; belt conveyers, n = 12; and buckets elevators, n = 8. dNumber of feed samples: total, n = 108;

auger conveyers, n = 12; belt conveyers, n = 8; buckets elevators, n = 8; weighing of macros, n = 4; grinding, n = 4, mixing

of ingredients, n = 4; pelletizing, n = 4; cooling, n = 4; silos expedition, n = 24; truck, n = 20.

The presence of the fungi on the

equipments of a feed mill possibilities risks to

mycotoxins production which facilitated also

the action of other deterioration agents, such as

bacteria (Coradi et al., 2011b, 2011c). The

fungi of the Aspergillus sp. produce aflatoxin

levels that high concentration cause

performance losses in the animals. The

Penicillium sp. in the feeding of animals cause

diarrhea, nephritis and gizzard erosion. The

Fusarium sp. produces trichothecenes in high

numbers, and they are potent inhibitors of

eukaryotic protein synthesis. Zearalenone is

also produced by Fusarium sp. and has strong

hyper-estrogenic effects, which result in

impaired fertility, stillbirths in females and a

reduced sperm quality in male animals. The

Fusarium sp., notably Fusarium

verticilliodides, Fusarium proliferatum and

Fusarium nygamai, as well as Alternaria sp. are

responsible to produce the fumonisins levels in

the products. As well the fungi, the bacteria

also can bring serious problems for the poultry

industry (Tables 2, 3, and 4) when presented in

the feeding. Reducing the bacterial

contamination in feed would also decrease

gastric dilatation, necrotic enteritis, and

gangrenous dermatitis by the Clostridia

botulinu; septicemia, abortions, encephalitis,

and eye infections by the Listeria sp.;

septicemia, cellulitis, swollen head, syndrome,

and airsaculitis by the Escherichia coli;

enteritis, diarrhea, and septicemia by the

Salmonella sp. On these conditions, the

identification of critical points in the production

process of according with the growth potential

of each pathogen can be an alternative to

prevent the contamination in the feed final



(Coradi et al., 2009). Table 5, shows the

variations of the water content (among at

10.76% w.b. to 15.50% w.b.) for animal meal

and corn, respectively. The high water content

in the raw materials compromises the quality of

the final diets. The amount of total water

content is the main limiting factor for the

growth of fungi. The water activity higher than

0.65 is required for active fungal metabolism.

Thus, the total water content levels higher than

150 g.kg-1 in cereals are usually required to

keep the fungi alive although large

discrepancies exist between fungi. In addition,

the Aspergillus sp., which is the less demanding

fungus, can grow at low water levels (13%-

18%), while Fusarium sp. needs 170-190 g.kg-1

substrates.

Table 5. Moisture content (% w.b.) of the

products

Sampling Moisture content (% w.b.)

Corn 15.50 + 2.40

Soybean meals 12.14 + 1.80

Animal meals 10.76 + 1.47

Grinding step 11.15 + 1.36

Mixing step 14.30 + 2.21

Mash feed 10.20 + 1.18

Pellet feed 11.20 + 1.31

The animal meals are one of the main

products involved in foodborne infections by

pathogens fungal and bacterial, as well as

physical and mycotoxin contamination. Table 6

was observed the proportion (%) of samples

infected by fungi and bacteria in the flow of

feed production. The high fungal contamination

observed in grain receiving (corn) of the feed

mill was influenced directly by field production

conditions. The growth of mycoflora on crops

is highly dependent on climatic conditions,

rainfall and temperature. A. flavus and

Aspergillus parasiticus grow best and produce

aflatoxin at temperatures greater than 21ºC.

Fungal invasion is enhanced when the crops are

stressed, such as during drought or insect

infestation. Field fungi are characterized by

requirements for a high water content (greater

than 200 g.kg-1

), and thus are vulnerable to

drying post-harvest. Moreover, during grain

storage, when the water activity of the grain

decreases to a range from 0.68 to 0.80, the

Aspergillus sp. and Penicillium sp.

predominate, with minor contributions from

Fusarium sp. However, researchers and

regulatory agencies have paid attention to

Salmonella contamination of livestock and

poultry feed by feed mill. Despite this attention,

a 1981 report by Williams concluded that there

seems to have been little change in the

Salmonella status of ingredients and poultry

feeds over the last 40 years (Williams, 1981). In

1990, the US Food and Drug Administration’s

Center for Veterinary Medicine (CVM)

announced a goal of Salmonella free animal

feed ingredients and final feed. Despite this

goal Salmonella contamination was a

widespread problem in the feed industry and the

control and elimination of Salmonella during

milling procedures has proved difficult (Table

6).

Table 6. Frequency of infected samples by fungi and bacteria in the flow production of the feed

Sampling

Frequencya (%)

Fusarium

sp.

Aspergillus

sp.

Penicillium

sp.

E.

coli

Salmonella

sp.

Cornb 78.57 68.57 87.14 - -

Soybean mealsc 62.50 75.00 81.25 - -

Animal mealsd - - - 64.58 45.83

Grinding stepe 33.33 41.66 50.00 25.00 0.00

Mixing stepe 8.33 50.00 33.33 58.33 41.67

Mash feede 33.33 41.67 50.00 66.67 50.00

Pellet feede 0.00 25.00 33.33 33.33 16.67

aPercentage of samples infected by fungi and bacteria.

bTotal number of samples, n = 70.

cTotal number of samples, n = 70.

dTotal number of samples (viscera, bone, meat, and feathers meals), n = 206.

eTotal number of samples, n = 40.



Reception

Automatic dosage

weighting

Grinding¹

Mixing¹ Pelleting

System of

transport

Microingredients System of

transport

System of

transport

System of

transport

System of

transport

Cooling Expedition of

mash feed¹

Yes

No

Expedition of

pellet feed¹

System of

transport

Pre-cleaning

Hopper

Animal meals¹

Drying

System of

transport

Receiving of

corn¹

System of

transport

System of

transport

Storage

Hopper Receiving

soybean

meal¹

System of

transport

Storage

F = 5.3x105

A = 3.8x103

P = 2.5x104

F = 2.1x103

A = 4.9x105

P = 5.3x104

F = 1.4x103

A = 4.2x104

P = 3.1x103

F = 1.3x101

A = 2.4x102

P = 2.7x102

E = 3.7x103

S = 2.2x102

E = 2.6x104

S = 5.3x103

F = 0.8x101

A = 1.4x102

P = 2.7x102

E = 2.1x102

S = 2.3x101

F = 0.2x101

A = 0.9x102

P = 1.5x102

E = 1.0x101

S = 0.3x101

A = 4.9x105

Figure 1. Diagram of the flow of feed production. ¹Samples collected for microbiological analysis of F

(Fusarium sp.), A (Aspergillus sp.), P (Penicillium sp.), E (Escherichia coli), and S (Salmonellas

sp.).

According to the results (Figure 1), the

presence of Salmonella in the feed was

consequence of the addition of animal protein in

the feed formulation. Similar results were found

by Wagner (2004) while identified 24.7% of feed

samples and 48.4% samples of protein meals

contaminated with Salmonella. The same

contaminating fungi responsible for field and

stored grains were found in the feeds and feed

ingredients, as observed in the Figure 1. The high

incidence of Fusarium in corn is from field. The

presence of damaged kernels, moldy, cracked or



broken, it is probably a function of the large

intensities of rainfall in regions associated with

high temperatures and delayed harvest. The

inadequate regulation of the harvesters is one of

the factors that have helped to increase the defects

in the grains, and therefore contamination during

storage. The presence of Aspergillus sp. and

Penecillium sp. is associated with high water

contents during the period that the products were

stored. The stress field in the product caused by

insects is another possibility that have boosted the

development of fungi during storage. In meal,

especially soybean, were also observed high

levels of contamination, including comparing with

corn. The addition in the feed composition of

ingredients such as meals, minerals, vitamins, and

others decreased the proportion of corn in the total

mixing process, and consequently were reduced

also the fungal and bacterial contamination.

0

1

2

3

4

5

6

7

8

9

Corn Soybean meal Grinding Mixing Mash feed Pellet feed

y 1

03

(CF

U.g

-1)

Fusarium sp.

Aspergillus sp.

Penicillium sp.

Expon. (Fusarium sp.)

Expon. (Aspergillus sp.)

Expon. (Penicillium sp.)

Ce

Ae

Be

AdBf

Cf

Bc Bd

Cc

AaBb

Bc

Cd

Ab

Cb

BaAa

Ca

Figure 2. Comparison and distribution of fungal contamination levels in different stages of the production

flow of the feed. Capital letters with similar meanings in columns and lower case letters with the

same meanings in the lines. y = number of fungal colonies multiplied by 10³.

Significant results were observed between

mash and pelleted feed. There were reductions in

the rates of infection by fungi and bacteria in the

step of pelletizing the pellet with temperatures

above 80 °C. It is worth noting that the

elimination of most bacterial and fungal

contamination in food processing do not eliminate

the possibility that these products are

contaminated the earlier stages of production. The

production of mycotoxins have occurred even in

the raw materials in the field, even during storage

and handling of products at the mill (Coradi et al.,

2011a). As seen in Figures 2 and 3, the presence

of colonies of fungi and bacteria in the feed end,

regardless of type of processing used compromise

the quality and safety of the product when

consumed by animals, since after the rations they

are still being processed remained fifty to one

hundred twenty days stored in silos on farms.

During this period, if the product moisture

content, temperature and relative humidity

favorable the microbial load may enhance the

production of mycotoxins that will directly affect

the animals. In this case the pellet feed and is an

important factor to be considered for ensuring the

safety and quality of products from the feed mill.

As observed in Figure 3 65% and 46% of wheat

flour samples of animal origin were infected by

Eschirichia coli and Salmonella species,

respectively.

Similar results were observed by the Crump

et al. (2002), while affirmed that the Salmonella

sp. contamination in feeds was associated with the

contamination of food producing animals.



0

1

2

3

4

5

6

7

8

9

Animal meals Mixing Mash feed Pellet feed

y 1

02

(CF

U.g

-1)

E. coli

Salmonellas sp.

Expon. (E. coli)

Expon. (Salmonellas sp.)

Bd

Ad

Bc

AbBb Bc

Ba

Aa

Figure 3. Comparison and distribution of rates of bacterial contamination at different stages of the

production flow of the feed. Capital letters with similar meanings in columns and lower case

letters with the same meanings in the lines. y = number of bacteria colonies multiplied by

102.

The cooling of the pellets has been

primarily responsible for the recontamination of

the final product while it not adequate

controlled. In the pelletizing operation, the

humidity and temperature of the pellets

increasing, however, for the preservation of the

feed must be dried at 12% (w.b.) and keep it

with low temperature to eliminate the

possibility the microorganism’s growth. The

temperature and pressure in pelletizing system

is important to guarantee the integrity and

durability of pellets, increasing percentage of

the amount of material intact (90%). However,

the drying and cooling must be efficient to

removal the water above of 12% (w.b.).

Scientifically, the granules (pellets) of larger

sizes are more irregular (whole pellets) and

have a higher percentage of empty space

between products of the finest, so the air is

movement easily through the particles, causing

a drying and cooling more uniform and efficient

when compared with smaller particles.

Analyzing the final pellet feed, the

contamination levels were present in much

smaller particles (approximately 10% of total),

which are water content levels is above of the

standards (16% w.b.) than whole pellets (12%

w.b.).

CONCLUSION

In the real operation conditions, the feed

industry had problems with microbiological

contamination in the various sectors of

production, interfering directly in the final

product quality. In general, the type of

contamination alternate by step to step of the

feed processing, and most of the time it was

punctuated by type of raw material and

processing. In addition, the feed processing

influenced positively in the reduction of

microbiological contamination in the final feed.

Moreover, the microbiological contamination in

the flow of production were characterized by

the set materials, equipment, machinery, rather

than the low quality of ingredients used in

formulating feed. The feed pelletizing reduces

microbiological contamination in final

products, positively. Conclusion that the

identification of critical points in the production

process combined usage of the adequate

cleaning and sanitation processes reduced the

risks of contamination of the feeds.

ACKNOWLEDGEMENTS

The authors would like to thank the

CAPES Foundation (Brazilian Ministry of

Education), Department of the Agricultural



Engineering and Federal University at Viçosa

for its financial support.

BIBLIOGRAFY REFERENCES

Annett, C.B.; Viste, J.R.; Chirino-Trejo, M.;

Classen, H.L.; Middleton, D.M.; Simko, E.

Necrotic enteritis: effect of barley, wheat

and corn diets on proliferation of Clostridia

perfringens type. A. Avian Pathol. v. 31, p.

599-602, 2002.

Brasil. Ministério da Agricultura e Reforma

Agrária. Regras para Análise de Sementes.

Brasília, DF, 1992.

Brasil. Portaria nº. 1428, de 26 de novembro de

1993. Estabelece a necessidade da melhoria

da qualidade de vida decorrente da

utilização de bens, serviços e ambientes

oferecidos à população na área de alimentos.

Diário Oficial, Brasília, nº. 229, p.18415,

1993.

Coradi, P.C.; Lacerda Filho, A.F.; Melo, E.C.

Análise de Perigos e Pontos Críticos de

Controle (APPCC) no processo de

fabricação da ração. Revista Eletrônica

Nutritime, v. 6, p. 1098-1102, 2009.

Coradi, P.C. Avaliação de uma fábrica de

ração para aves: instalações, processos e

produto final. Viçosa: UFV/DEA, 2010a,

191p. (Tese de Doutorado).

Coradi, P.C.; Melo, E.C.; Lacerda Filho, A.F.;

Chaves, J.B.P. Avaliação do Uso de

Ferramentas da Gestão da Qualidade em

Indústria de Ração para Aves. In: A

Engenharia Agrícola e o Desenvolvimento

das Propriedades Familiares. Ed.

Jaboticabal, SP: Jaboticabal: Sociedade

Brasileira de Engenharia Agrícola, 2010b, p.

1-20.

Coradi, P.C.; Lacerda Filho, A.F.; Melo, E.C.

Quality of raw materials from different

regions of Minas Gerais State utilized in

ration industry. Revista Brasileira de

Engenharia Agrícola e Ambiental, v. 15,

p. 424-431, 2011a.

Coradi, P.C.; Lacerda Filho, A.F. de; Melo,

E.C. Avaliação da presença de salmonela

nas farinhas de origem animal provenientes

do estado de Minas Gerais. In: XL

Congresso Brasileiro de Engenharia

Agrícola (CONBEA), 2011b, Cuiabá, MT,

Anais...... Jaboticabal, SP: Sociedade

Brasileira de Engenharia Agrícola (SBEA),

2011b. v. 1. p. 1-4.

Coradi, P.C.; Lacerda Filho, A.F.; Melo, E.C.;

Chaves, J.B.P. Contagem de Colônias de

Fungos em Subprodutos de Origem Animal

Processados no Estado de Minas Gerais. In:

XL Congresso Brasileiro de Engenharia

Agrícola (CONBEA), 2011c, Cuiabá, MT,

Anais....Jaboticabal, SP: Sociedade

Brasileira de Engenharia Agrícola (SBEA),

2011c. v. 1. p. 1-4.

Crump, J.A.; Griffin, P.M.; Angulo, F.J.

Bacterial contamination of animal feed and

its relationship to human foodborne illness.

Clin. Infect. Dis. v. 35, p. 859-865, 2002.

Curtain, L. Economic study of Salmonella

poisoning and control measures in

Canada. Working Paper nº. 11. Agriculture

Canada, Canada Marketing & Economics

Branch Ottawa, 1984.

Diener, U.H. & Davis, N.D. Aflatoxin

production by isolates of Aspergillus flavus.

Phytopathology, v. 56, p. 1390-1393, 1966. Eriksen, G.S.; Pettersson, H. Toxicological

evaluation of trichothecenes in animal feed.

Anim. Feed Sci. Technol. v. 114, p. 205-

239, 2004.

Geornaras, I.; Hastings, J.W.; Van Holy, A.

Genotypic analysis of Escherichia coli

strains from poultry carcasses and their

susceptibilities to antimicrobial agents.

Appl. Environ. Microbiol. v. 67, p. 1940-

1944, 2001.

Henson, S.J.; Holt, G.; Northern, J. Cost and

benefits of implementing HACCP in the UK

dairy processing sector. Food Control, v.

10, p. 99-106, 1999.

Hinton, A.; Cason, J.A.; Ingram, K.D. Tracking

spoilage bacteria in commercial poultry

processing and refrigerated storage of

poultry carcasses. International Journal of

Food Microbiology. v. 91, p. 155-165,

2004.

Lacaz, C.S.; Porto, E.; Martins, J.E.C.

Micologia médica: fungos, actinomicetos e

algas de interesse médico. 8ª ed. Sarvier,

São Paulo, 1991.

Maldonado, E.S.; Henson, S.J.; Caswell, J.A.;

Leos, L.A.; Martinez, P.A.; Aranda, G.;

Cadena, J.A. Cost-benefit analysis of

HACCP implementation in the Mexican

meat industry. Food Control, v. 16; p. 375–

381. 2005.

Roberts, T.; Ahl, A.; McDowell, R. Risk

assessment for foodborne microbiological

hazards. Washington: USDA Miscellaneous

Publication, 1995.

Rotter, B.A.; Prelusky, D.B.; Pestka, J.J.

Toxicology of deoxynivalenol (vomitoxin).

J. Toxicol. Environ. Health, v. 48, p. 1-34.

1996.



Sindirações. Sindicato Nacional da Indústria de

Alimentação Animal. Perfil da Indústria

Brasileira de Rações. São Paulo, 2008.

Speck, M.L. Compedium of methods for the

microbiological examination of Foods,

Washington: APHA/Technical Committee

on Microbiological for Foods. 914p.

Tabib, Z.; Jones, F.T.; Hamilton, P.B.

Microbiological quality of poultry feed and

ingredients. Poultry Sci. v. 60, p. 1392-

1397, 1981.

Taniwaki, M.H. Meios de cultura para

contagem de fungos em alimentos.

Sociedade Brasileira de Ciência e

Tecnologia de Alimentos, v. 30, p. 132-

141, 1996.

Unnevehr, L.J. Food safety issues and fresh

food product exports from less developed

countries. Agric. Econ. v. 3, p. 231-240,

2000.

Veldman, A.; Vahl, H.A.; Borggreve, G.J.;

Fuller, D.C. A survey of the incidence of

Salmonella species and Enterobacteriaceae

in poultry feeds and feed components. Vet.

Rec. v. 136, p. 169-172, 1995.

Wagner, D. Microbiological data summary

from FDA feed commodity surveys. CDC,

Animal Feed Workshop Presentation, 2004.

Weidenborner, M. Encyclopedia of Food

Mycotoxins. Springer-Verlag, Berlin, 2001.

Williams, J.E. Salmonellas in poultry feeds - a

worldwide review. Part I: Introduction.

World’s Poultry Sci. J. v. 37, p. 6-19,

1981.

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