Reducing food safety risk in pack houses
Industry Best PracticeResearcher Elizabeth Frankish reports on the project she has begun to identify where food safety risks occur in apple production and to develop a code of practice to help growers, packers and others along the supply chain minimise those risks.
Protective clothing is worn to prevent contamination from food handlers.
Apples and pears are rightfully regarded as safe and nutritious to eat but there is a long history of foodborne illness outbreaks involving apples outside Australia. Apple juice has been associated with outbreaks of Salmonella and E. coli O157:H7 for more than 100 years, with wash water often identified as the source of the pathogens, while an outbreak of Listeriosis related to caramel apples in the USA highlighted the potential for apples to carry human pathogens and the possible increased risks along the apple supply chain.
Whole of supply chain approach
The whole supply chain shares food safety hazards, with the customer-interface point of the chain holding the greatest risk. As customers continue to ask “Where does my food come from?” and businesses take advantage of consumer interest in provenance and the power of social media, growers and packers will share a greater load of the risk burden. A through-chain approach to risk management is now expected so all stages in the chain need a sound understanding of their role in minimising risk.
Growers and packers invest significant time and money in applying good agricultural and hygienic practices and ensuring compliance with certified programs such as Freshcare. However, growers are unable to determine the absolute food safety risks that exist either before or after quality assurance measures have been implemented.
As a result, there is also a lack of knowledge about what contribution these early production stages make within the supply chain to the final consumer risk.
If fruit becomes contaminated with pathogens it is difficult to eliminate and value-add operations such as fresh-cut processing, are not guaranteed to reduce pathogens to acceptable levels. Prevention of contamination in the orchard and its amplification at the pack-house is, therefore, critical for consumer safety.
In the modern food industry, there is no room for complacency about microbial hazard prevention and ongoing improvement in food safety.
Keeping orchards and pack-houses clean
Demonstration of adequate risk mitigation of pathogens in the orchard and pack-house is becoming increasingly important for overall supply chain integrity and possible future regulatory controls.
There are many opportunities for the contamination and spread of microbial pathogens in a pack-house. Water, food handlers, equipment contact surfaces and the open environment, where dust, pests and birds can enter, are the most likely sources of microbial hazards. Damage in the orchard from insects and birds, and bruising on fruit, also contribute to microbial loads entering the pack-house and provide opportunities for pathogens to proliferate and contaminate intact fruit.
The likelihood of contamination varies between producers and depends on other conditions including weather, specific agricultural practices, the training level of workers and the level of control of pre-requisite food safety programs such as pest control and equipment and water sanitation. During growth, environmental factors can influence microbial hazards, whereas post-harvest there is potential for a significant level of control over the environment and mitigation of prior contamination.
Food safety code of practice
With this background in mind, the University of Tasmania established a research project to identify microbial hazards in apples and to quantify the risk to human safety from those hazards. The project is supported by the ARC Industrial Transformation Training Centre for Innovative Horticultural Products, APAL and the Fresh Produce Safety Centre.
Our research activities to date highlight the variability in orchard and pack-house food safety controls and growers and pack-house operators have expressed interest in receiving clearer, targeted guidance to help them reduce food safety risks.
To provide the highest level of due diligence in food safety, we will identify the key practices and input controls specific to apples that are required to minimise risks. Then we will develop a guide on how best to apply these risk minimisation controls as a code of practice for the pome fruit industry.
Pack-house equipment provides multiple sites for pathogen harbourage.
Risk assessment decision-support tool
We will quantify the risk of apples getting contaminated with the pathogens Salmonella, Listeriamonocytogenes and E. coli O157:H7. Then, using observations and experiments, we will identify how practices and inputs affect this risk so we can develop a risk assessment model.
The model will be based on survival and growth data for these pathogens and key growing and packing parameters, with the ultimate aim to produce a user-friendly decision-support tool that will allow growers and packers to measure risk in their operations.
As the risk model is developed and refined the variables that have the most effect on risk and the ways to best mitigate that risk through management practices will be identified and their relative importance quantified.
The model will be based on established principles of food safety risk assessment and incorporated into user-friendly computer software. It will make use of both qualitative information gathered from orchard and pack-house field trips and quantitative data, such as storage temperatures and sanitiser levels in wash systems.
The harvest-to-consumption pathway will underpin the decision-support tool and provide a risk ranking for apples out of the pack-house, thus allowing growers and packers to identify and focus on the most important and effective risk mitigation strategies.
The decision-support tool will provide a more objective measurement of sources of microbial food safety risk and allow more consistent application of risk management across the industry, thereby helping industry to demonstrate its reliability in supplying safe product and consistently minimising risk.
The relevance of current microbiological criteria assigned to fruit will be reviewed and growers and packers will be able to adjust and refine their microbial monitoring programs and quality control activities according to their risk ranking.
Through use of the decision-support tool and code of practice, the overarching goals of this research are to:
- Develop the risk assessment skills of growers and their pack-house operational and QA personnel.
- Provide a better understanding of the multiple hurdles needed to ensure food safety control.
- Identify and quantify sources of risk so as to focus effort and resources where they are best able to minimise hazards and mitigate risk.
- Provide a framework for consistency of risk assessment and risk management across the pome fruit industry.
- Open channels of communication on the most effective controls to prevent potential outbreaks or food recalls due to microbial contamination.
Findings from the research and the software tool will be progressively disseminated to industry.
Acknowledgement
Funding and in-kind support is being received for this project from APAL, the ARC Industrial Transformation Training Centre for Innovative Horticultural Products (University of Tasmania) and the ARC Centre for Food Safety in Fresh Produce (University of Sydney).
