Wet brewers’ spent grains and wet brewers’ spent yeast: problems associated with their usage and suggested solutions: a case study of the Ejisu-Juaben Municipality of Ghana

M Boateng, D B Okai, Y O Frimpong and Y Y Zeebone

Department of Animal Science, Faculty of Agriculture, College of Agriculture and Natural Resources, KNUST, Kumasi-Ghana
mickyboat@gmail.com

Abstract

A survey was conducted to obtain information on the acquisition, usage and problems associated with the use of wet brewers’ spent grains (WBSG) and wet brewers’ spent yeast (WBSY), in the Ejisu-Juaben Municipality of the Ashanti Region of Ghana and also to suggest possible solutions to the problems. Semi-structured questionnaires were administered to 20 pig farmers from the Ejisu-Juaben Pig farmers and Processors Association (EJPFPA). Questions asked were related to the demographic characteristics of the respondents, the systems by which pig farms were managed, feeds and feeding, usage of WBSG and WBSY and the problems associated with the use of the 2 brewery by-products. Results obtained from the survey were coded into similar views after which they were analysed using the descriptive statistics described by the Statistical Package for Social Sciences (SPSS version 16.0).

All the respondents fed WBSG to their pigs whilst only 35% of them fed WBSY. The 65% of the respondents who were not feeding WBSY stated short shelf life, tedious processing and health related issues as the reasons behind their stance. Majority of the farmers indicated that their main constraint in the use of WBSG and WBSY was the cost of transporting the products from the breweries to their farms. Fifty-five (55) percent of the farmers reported cases of spoilage in the usage of WBSG whilst all the users of WBSY (35% of respondents) did not encounter any such problems. Availability of WBSG was also one of the constraints associated with the use of WBSG. It was concluded that cost of transporting is the main problem associated with the usage of the 2 products. Rapid deterioration, availability, tedious processing and health related issues were identified as some of the problems associated with the use of the 2 brewery by-products. Finding alternatives which are readily available and less expensive within the Municipality, and the use of simple, less tedious on-farm processing techniques like sun-drying and ensiling were some of the other interventions that may help reduce the problems associated with the use of these products.

Keywords: agro-industrial by-products, brewery by-products, feed, mould, pig farming

Introduction

Livestock production constitutes a very important component of agriculture in developing countries (Otte and Knips 2005). Cost of producing livestock, especially non-ruminants, has become high due mainly to the high cost of conventional feed ingredients which are mostly imported. Earlier, Okai et al (2001) had indicated that, the major cost item in producing monogastric farm animals like pigs is feed which hovers between 60 and 70% of the total operating cost. It has been established that the high cost of conventional feed ingredients is partly due to their high demand which has arisen from the competition between humans, industries and animals (Sogbesan and Ugwumba 2008; Ani et al 2013). Furthermore, the increase in demand for grains as raw materials in biofuel production, according to von Braun (2007) has led to unprecedented rates of increase in prices of grains and has thus threatened the use of grains in livestock enterprises. For these reasons, a host of nutritionists have channelled their efforts into finding cheaper alternatives to conventional feed ingredients (Okai et al 2013).

Non-conventional feed resources (NCFR) which include agro-industrial by-products (AIBP), according to Atuahene et al (2000), Amoah et al (2013) and Darkwa et al (2013) represent a vast animal feed resource, which have not been adequately exploited and are far cheaper compared to conventional feed resources. Erukainure et al (2010) explained that some of the by-products produced by industries, may eventually become pollutants if they are not channeled into useful forms such as animal feed. Furthermore, Ha et al (1996) indicated that the cost involved in disposing of waste by-products by industries are so high that they drastically reduce the profit margins of industries. Thus, a better approach to this problem is the usage of these by-products or industrial wastes as feed resources by farmers who still ponder over ways of reducing there operating costs so as to maximize their profit margins.

In Ghana, some common by-products which are used by pig farmers are wet brewers’ spent grains (WBSG) and wet brewers’ spent yeast (WBSY). These feed ingredients which are produced after brewing several kinds of beverages, according to Okai et al (1998), are some of the most common by-products which are used extensively in feeding pig,s especially those in places very close to breweries. Like most NCFR and AIBP, the usage of WBSG and WBSY is hindered by several factors and thus animals fed these feed materials may not attain their optimum growth potential. It will therefore be important if proper remedies are found to address these issues. Thus this study was carried out to ascertain the constraints associated with the use of WBSG and WBSY by pig farmers in the Ejisu-Juaben Municipality in the Ashanti Region of Ghana and also to suggest some possible solutions to these problems.

Materials and Methods

Location of study

A survey was conducted in the Ejisu-Juaben Municipality which is located in the central part of the Ashanti Region to find the problems farmers face in the use of WBSG and WBSY. The Municipality occupies a land area of 637.2 km² and forms about a tenth of the Region (Ghana Statistical Service 2008). The Ejisu-Juaben Municipality (EJM) is bounded by the Kwabre, Afigya-Sekyere, Asante Akyem North, Asante Akyem South and Bosomtwi Districts, and the Kumasi Metropolis (Ghana Statistical Service 2008). Agriculture is the major employer of most of the inhabitants of the Municipality, contributing to 61.5% of the total work-force (EJMA 2012). Like most municipalities in Ghana, commerce and services are gradually infiltrating into EJM as about 30% of its inhabitants are employed by these sectors (EJMA 2012). 

Data collection      

Before the study, a preliminary survey was undertaken in the Municipality and places visited were the offices of the Ministry of Food and Agriculture (MoFA) and Ejisu-Juaben Pig Farmers and Processors Association (EJPFPA). Also some pig farms were visited.

Semi-structured questionnaires were then administered to 20 pig farmers who were all members of the EJPFPA. Questions asked were those pertaining to the respondents’ demography, stock size, the systems of management, sources of feed and feed ingredients, types of non-conventional feeds used, and acquisition, usage and problems associated with the use of WBSG and WBSY.

Data analysis

Data collected were coded into groups of similar views before being analyzed with the descriptive statistics described by SPSS Version 16.0. (2007). The results were presented in tables using frequencies and percentages.

Results and Discussion

Demographic characteristics of respondents

Demographic characteristics of farmers such as their age and education levels have been described as an important tool in determining the amount of physical work a farmer can do and how quick they can adopt innovation (Idowu et al 2012; Awunyo-Vitor et al 2013). As shown in Table 1, most of the respondents (80%) were between the ages of 20 and 49. This is an indication that most of them were still in their productive years and can cope with the work associated with raising pigs. These results are similar to those reported earlier by Frimpong (2010) and Mohammed (2010) where 76 and 78% of pig farmers respectively were between the ages of 20 and 49. It was also observed from the survey that, majority (75%) of the respondents had received formal education. Only a quarter of the farmers interviewed had not received any form of formal education. Contrary to these findings, majority (67%) of the pig farmers interviewed in the Northern Region had not acquired formal education (Afari 2012). These findings corroborate with those of the Ghana Statistical Services (GSS 2008) which indicated that the majority (80.6%) of adults in the Ashanti Region have had a form of formal education compared to the Northern Region which had only 28% of its adults acquiring some form of formal education.

It can also be inferred from Table 1 that operators of the pig production enterprises in the EJM are predominantly (80%) owners of the enterprise. Akuffo (2008) and Asumang-Owusu (2014) reported similar figures and concluded that pig farming is a profitable and sustainable venture and also serves as a tool for poverty alleviation. Mohammed (2010) however indicated that, most people operated their own farms since that was the best way to maximize their profits and reduce chances of being swindled by employees.

Stock size, management and feeding

As shown in Table 2, 30% of the respondents had stock sizes within the range of 1 and 50, 25% of them had 51 to 100 and another 25% had stock sizes within the ranges of 151 and 200. The remaining 20% of farmers interviewed had more than 200 pig. Unlike the Tamale Metropolis in the Northern region where majority of the farmers (82.5%) had less than 50 pigs (Afari 2012), majority of the respondents (70%) in the EJM had more than 50 pigs. This confirms the report made by the Obuasi Municipal Assembly (OMA 2012) and Ministry of Food and Agriculture (MoFA 2013) that pig farming is growing faster in the Ashanti Region compared to several other regions in Ghana.

Majority of respondents (95%) raised pigs under the intensive system of production. Only one farmer (5%) practiced the semi-intensive system (Table 2). Managing pigs under the intensive system is said to be easier and relatively little space is required to raise a large number of pigs compared to other systems of production (Rere 1999). Also, pigs are relatively safe from predators and thieves. Ingesting of human excreta, by extensively managed or free ranging pigs, which can lead to worm infestation in pigs can also be avoided. It has also been suggested that the system of production practiced in the EJM is influenced by the rainfall distribution pattern which allows for all year cropping. Thus when pigs are kept on the extensive system, farmers may incur coststhrough the payment of compensation for crops which pigs may destroy. Afari (2012) however noted that the majority of the pig farmers in the Tamale Metropolis practiced the semi-intensive system of production during the long dry harmattan period when very few farmers are still involved in crop farming. Stuart (2009) also explained that pigs kept intensively largely consume household and agricultural scraps and can therefore be seen as highly resource efficient. This may justify why the majority of the respondents practiced the intensive system.

Eighty-five percent (85%) of respondents practiced wet feeding, 5% practiced dry feeding and the remaining 10% practiced both dry and wet feeding. The high percentage of pig farmers that practiced wet feeding may be due to the fact that dry feeding increases the incidence of respiratory-related diseases in pigs (Reese et al 2002). In an earlier work in EJM, Frimpong (2010) reported that about 80% of pig farmers interviewed in the Municipality practiced wet feeding.

Usage of WBSG and WBSY and problems associated with their usage

All the farmers interviewed (100%) used WBSG (Table 3). It can however be observed from Table 3 that only 35% of the farmers interviewed used WBSY. The farmers who did not use WBSY indicated that the addition of the product to the diet of pigs normally increased the incidence of diarrhoea, especially in the piglets. Also, tedious processing and fast deterioration rates were some of the reasons behind the low usage of WBSY. The WBSG and WBSY used by respondents were obtained from a local large scale brewery.

Expenditure on WBSG and WBSY

The cost of the WBSG was dependent on the weight of the product that a truck could carry. Farmers however indicated that they paid a minimum of GH¢ 25 up to a maximum of GH¢ 40 for a truckload of WBSG. The WBSY was however given to farmers for free on request after paying for WBSG. Much of the cost incurred in obtaining WBSG and WBSY was attributed to the transportation of the product from the brewery to the farm. Since the association had a truck which transported mainly feed ingredients at a cost for farmers, most of the members of the association used this truck in transporting the WBSG. The respondents indicated that, they paid between GH¢ 100 and 150 for transporting a truckload of WBSG. Most of the farmers (70%) therefore intimated that, the transportation cost was their major problem in using both brewery by-products. In a similar study involving respondents from the Afigya-Kwabre District Pig Farmers Association (AKDPFA), Boateng et al (in press) indicated that pig farmers even paid more in transporting WBSG and WBSY. These authors indicated that pig farmers paid between GH₵ 200 to GH₵ 260, which is more than 500% of the cost of the products, as transportation cost and attributed the huge transportation cost to the fact that farmers hire commercial vehicles to cart the WBSG and WBSY to their farms.

Storage of WBSG and WBSY

Table 3 indicates that, majority of the farmers (60%) stored the WBSG in pits, about a third of the farmers (35%) stored their WBSG under shade whilst only 5% of them kept theirs in the open. Otchere-Anane (2005) and Tetteh (2005) explained that open storage of WBSG is better than storage under shade since the latter contributes to the formation of a relatively humid atmosphere which speeds up the proliferation and activity of moulds and some facultative bacteria such as E. coli, Klebsiella sp. and Proteus sp. All the respondents who used WBSY indicated that they stored their WBSY in 1000L tanks. According to Anim-Ofori (2014) and Boateng et al (in press), storage of WBSY in 1000L tanks is a common practice by pig farmers in the Kwabre-East and Afigya-Kwabre Districts respectively.

Spoilage of WBSG and WBSY

Some 45% of the respondents interviewed indicated that they recorded no spoilage of WBSG but majority of them (55%) indicated that they encountered spoilage (Table 4). Boateng et al (in press) working on the problems pig farmers encounter with the use of WBSG and WBSY reported that about 65% of farmers interviewed in the Afigya-Kwabre District indicated that spoilage of the products is one of the major problems they face. Out of the 11 farmers who encountered spoilage, 9 (81.8%) of them indicated that spoilage was based on the extent of mould growth whilst the remaining 18.2% indicated that spoilage was based on the change in the colour of the WBSG. According to some 81.8% of the farmers who encountered WBSG spoilage, the quantity of WBSG that got spoilt was less than 10% of the total consignment obtained whilst the rest of them indicated that they lost about 11 to 20% of the WBSG through spoilage. It is noteworthy that, about a third (36.4%) of the farmers encountering spoilage of WBSG fed the supposedly spoilt product to the pigs whilst most of them (63.6%) discarded it. Moulds are known to have adverse effects on production and the health of farm animals (Adams et al 1993). It has also been observed that feeding mould infested feed may reduce the digestibility and palatability of the feed. Also, moulds are known to produce mycotoxins which may even be carcinogenic to animals and humans (Adams et al 1993). Furthermore, it has been observed that moulds may depress animals’ resistance to metabolic and infectious diseases (Adams et al 1993; Marković et al 2005).

All the farmers who used WBSY however indicated that they did not encounter problems with spoilage. This contradicts with what had been reported by Boateng et al (in press), that majority of WBSY users (71.4%) encountered problems with spoilage. It must however be stated that, the respondents who were not feeding WBSY to their pigs indicated that, they ceased using WBSY because of its high deterioration rate; the energy required to heat it to prevent deterioration; the tedious work involved in heating it and the fact that most piglets had diarrhoea upon the consumption of diets containing WBSY.

Availability of WBSG

Some thirty percent (30%) of the respondents stated that the availability of WBSG was also a problem. This problem can be attributed to the fact that only one brewery serve almost all the farmers in the Ashanti Region (Okai 1998).

Suggested solutions to the problems

Some possible solutions to some of the problems faced by pig farmers in the use of WBSG and WBSY include the following:

Transportation and availability of WBSG and WBSY

Farmers who are not so close to the brewery should find some other alternatives to WBSG and WBSY. Westendorf et al (1999) for example indicated that the use of by-products from brewery should be limited to farms that are very close to these breweries since most brewery products are bulky, contain a lot of water and thus are costly to transport. Furthermore, the fact that most inhabitants of EJM are engaged in crop-based agriculture (MoFA 2013) means that, there are several AIBP that can be obtained and used as feed ingredients for pigs.

Spoilage and storage

Several strategies have been proposed for the processing of WBSG and WBSY into forms that do not deteriorate easily. Amoah et al (2013) opined that WBSG can be ensiled in polyethylene bags. Furthermore, sun drying has been suggested to be a cheaper way of processing WBSG (Amoah et al 2013). It has also been suggested that, mixing watery ingredients like WBSY with dry ingredients like rice bran or wheat bran and then drying may help to reduce its rate of deterioration (El-Shafey et al 2004). Again, Crawshaw (2004) stated that, when there is mould growth on feed ingredients such as WBSG, mould or toxin inhibitors or binders can be added to the diet to reduce the harmful effects caused by the ingestion of such contaminated feeds. Prompt usage of highly perishable feed ingredients have also been suggested by Wyss (1997).

Tedious processing of WBSG and WBSY

 Birhan (2014) stated that, farmer associations can set up processing plants that will concentrate on the processing of ingredients which are deemed too difficult or tedious to process. It has also been suggested by Birhan (2014) that, stakeholders in the animal production industry such as animal farmers and nutritionists conduct studies aimed at characterizing the nutrient profiles of non-conventional feed ingredients like WBSG and WBSY so that farmers may know the levels of these ingredients which are acceptable in the diets of different categories of farm animals. Furthermore knowledge of the composition of some of these ingredients can help in dealing with the levels of anti-nutrients in them.     

Conclusion

• It can be concluded from this study that the cost of transporting WBSG and WBSY is the major problem faced by pig farmers in the use of the two ingredients. Other constraints in the usage of WBSG and WBSY include availability, tedious processing, health related issues and rapid deterioration. The interventions suggested, if adhered to by farmers would go a long way in ensure a more effective use of these by-products and thus help in reducing the production cost and the cost of pork. These interventions may also help in increasing profit margins of local pig farmers.

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Received 25 December 2014; Accepted 26 December 2014; Published 1 January 2015

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