Fate of selected pathogens during the production of raw milk cheese Dr Duncan Craig:

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1 SUGGESTED FSANZ STUDENT PROJECT TOPICS Listed below is a list of project ideas, currently of interest to FSANZ. Please note that students are not limited to the project ideas described below. Students and course coordinators are encouraged to contact FSANZ to discuss other potential project ideas. For further information, contact the Strategic Science officer, Ms Lisa Tengdahl (lisa.tengdahl@foodstandards.gov.au) or the relevant contact officer listed below. To call in Australia, (02) and New Zealand, (04) ). (Note: please dial the relevant country number and if need be reception can transfer you internationally (thus avoiding the international call charge)). FOOD TECHNOLOGY/MICROBIOLOGY Fate of selected pathogens during the production of raw milk cheese With increasing consumer interest in raw milk cheese, there is a need for a better understanding of the fate of low levels of milk-borne pathogens such as Salmonella spp., E. coli, S. Aureus or Listeria monocytogenes which may be present in raw milk and the impact of cheese making steps on their growth and survival. A study would consider a specific milk (e.g. raw cow, goat or sheep milk) and cheese type (e.g. cheddar cheese, blue cheeses or softsurface ripened cheeses) and determine whether these organisms grow, survive and/or become inactivated during the production of the cheese. Survey of ready-to-eat horticulture products An increasing array of ready-to-eat horticulture products is now available to Australian consumers. These include pre-cut salad ingredients, sprouts, pre-prepared salads, etc. In the past year, a range of plant products have been implicated in outbreaks of foodborne illness in Australia and overseas e.g. Salmonella in sprouts and rockmelons. Factors including the raw materials and their production system, post-harvest handling, preparation, packaging and storage influence the microbiological status of these products. A study could examine the microbiological status of selected products at point of sale, as well as determine the impact of production and processing steps on the microbiological status of these products. Cold chain refrigeration temperature survey Maintenance of the cold-chain throughout the storage and distribution of perishable products is important not only for product quality but more importantly, for the microbiological safety of the food product. Generally the growth of pathogenic microorganisms is suppressed at refrigeration temperatures (< 5 o C) with a few exceptions, i.e. Listeria monocytogenes. Fluctuations in temperature during distribution or storage, or indeed a breakdown in the integrity of the cold-chain, particularly during retail display, food service and/or consumer households, can impact on the number of microorganisms present in a food. Published and

2 unpublished data obtained from surveys in Australia and overseas consistently show the refrigerated retail cabinet as a weak link in the cold chain. However, this data is limited (i.e.: a particular food) or out-of-date, whilst data pertaining to other stages of the cold-chain (i.e.: the food service area and consumer households) may be lacking altogether. A study could identify temperatures of retail and food service refrigeration units and domestic refrigerators. Microbiology of specialty eggs A range of exotic processed egg products are being found in the Australian marketplace. These include salted and century eggs and fertilized eggs. Little technical information is available on the processing operations and conditions for these products, and the extent to which microbiological hazards may be reduced or increased during these processing steps. Factors including raw material status, inputs, processing steps, and storage will all influence the microbiological status of these products. A study could define the major steps in the production of these products and examine the fate of selected pathogens during production. Alternatively, a study may involve a survey of their microbiological status at point of sale. Effect of dairy processing technologies on milkborne pathogens In assessing the safety of dairy products, FSANZ has become aware of a range of new technologies that could be used as alternatives to pasteurizations (typically high temperature short time treatment at 72 o C for 15 seconds). These technologies include ultra-high pressure processing, pulsed electric field, ultrasonication, bactofugation, etc. Projects that provide data on the effect of these technologies on pathogens such as Salmonella spp., E.coli, S. aureus, Listeria monocytogenes and B. cereus would assist in determining the capacity of these alternatives technologies to produce safe dairy products. Nanotechnologies for food functionality Mr Dennis Thomas: Dennis.Thomas@foodstandards.govt.nz A number of technologies have been proposed using enhanced processing of existing ingredients and additives to achieve foods with different properties to those using conventional processes. The properties may be of the food matrix (eg clear instead of cloudy emulsion, no need for added emulsifiers, enhanced edible films) or of the food when it is eaten (eg increased or decreased absorption in the stomach). These technologies include nano-emulsification and encapsulation at the nano scale. A possible project would be: to identify and describe near-to-market technologies to outline the expected technological and product outcomes in foods to identify if the use of these technologies could result in reduced public health and safety or in consumers being misled.

3 Natural extracts replacing food additives for functional purposes in food Mr Dennis Thomas: Technological functions in foods (eg thickening, colouring) are achieved through the use of foodstuffs, additives, and processing technologies. As a generalisation foodstuffs, eg flour, do not need explicit permission to be added and are labelled just using their common names; additives on the other hand, including additives derived from foodstuffs, require permission in the Australia New Zealand Food Standards Code before use, and have to be labelled with both their technological function and their name or additive number (if there is one). There is a large amount of research and commercialisation effort in developing extracts (particularly from food sources) that are aimed at meeting the definition of a foodstuff but that (also) provide a technological function. This is in response to some consumers wishes for products that have less additives (and numbers) also commonly referred to as clean labelling. Examples include cornflour, saffron, lemon juice, and more latterly black grape juice extract and rosemary oil. A possible project would be: identify emerging and recently released products and technologies aimed at commercialising ingredients providing technological functions in foods identify if these new products and technologies present any safety issues, and if so define these and compare them with their traditional counterparts identify any controls in place in Europe and USA for this class of ingredient recommend whether or not there is a need for additional controls in Australia and New Zealand. Nanotechnology and Food Dr Paul Brent: Paul.Brent@foodstandards.gov.au The emergence of nanotechnology and its potential application in many fields means governments around the world are considering the potential benefits and risks of nanotechnology. Food is one area where nanotechnology has potential applications, although FSANZ has not yet received any applications to amend the Australia New Zealand Food Standards Code (the Code) to permit any foods developed using nanotechnology. FSANZ, along with food regulators in other countries, are assessing whether their risk assessment processes and regulatory arrangements are adequate for ensuring the safety of foods that may incorporate nanotechnology. (See cfm) Small projects focussing on aspects of nanotechnology could be developed by students in collaboration with FSANZ around one of the following themes: Characterisation and metrology aspects of nanometre scale particles in food. The occurrence of nanometre scale particulates in traditional/conventional foods and estimating nanometre scale particles in the Australian diet.

4 Marketing and acceptance of nanotechnology in the food sector industry and consumer attitudes to the benefits and perceived risk of nanometre scale particles in food. Potential comparison of consumer perceptions and behaviours between different countries. TOXICOLOGY/CHEMICAL SAFETY Compositional analysis of food derived from transgenic or cloned animals Ms Lynda Graf: One of the key components of the safety assessment of genetically modified food is the compositional analysis of the food and its comparison to the conventional counterpart to identify any significant differences. Any identified differences can then be further investigated for their impact on the safety and nutritional adequacy of the food. Most of the work that has been done in this area has focussed on GM plants, and very little information is available on the composition of food products derived from GM or cloned animals. This project would therefore analyse the composition of a food derived from either transgenic or cloned animals (e.g. milk) and compare it to that of an appropriate control to determine if there are any significant differences, and if so to determine what impact such differences may have on the safety and/or nutritional adequacy of the food. The project could also research the general availability of compositional data from foods derived from non-gm animals, as this will be useful information on the typical variation in the food supply. Safety of plant bushfoods Dr Utz Mueller: Utz.Mueller@foodstandards.gov.au Native plants are increasingly being marketed as foods. While many of these foods may be safe for human consumption, there is potential for harm in some cases if the food is not prepared correctly or if an analysis has not been carried out to identify toxins or antinutritional factors. This project could examine one or more bush foods currently on the market and analyse the composition of the food to determine if there are substances present which may potentially cause harm. Alternatively the project could examine a range of currently available plant bushfoods and the data to support their safety. COMMUNICATIONS Effectiveness of food recall public advertising Dr Barbara Butow: Barbara.Butow@foodstandards.gov.au One of FSANZ s responsibilities is to coordinate food recalls on behalf of the Australian States and Territories. A food recall occurs when a product on the market is found to be potentially unsafe, and in most cases, the manufacturer agrees to undertake the recall voluntarily. Food recalls are classed as trade or consumer level depending on the extent of product distribution. When a consumer level recall occurs, a number of different communication strategies are used to notify the public of the specific product, the nature of the problem and where to return the product. The most common forms of communication are newspaper advertising, notification of subscribers to FSANZ information and notification on government agency websites. In some cases, store notices, media releases or press conferences can be used.

5 A study could examine the effectiveness of current food recall communication strategies, and suggest alternative strategies, potentially using emerging communication technologies. REGULATORY ANALYSIS Estimating the cost of Foodborne Illness due to Listeria monocytogenes Jason March: Estimating the cost of foodborne illness due to pathogens like Salmonella spp., Listeria monocytogenes and Campylobacter spp. in food could be an important component of the cost benefit analyses when FSANZ assesses major applications and proposals to introduce or revise food standards. Because of the demanding and complex nature of such estimates we cannot undertake specific studies in support of each assessment that FSANZ undertakes. It becomes necessary to either commission external studies or draw on the previous work and findings of other organisations. In order to facilitate our work, we can benefit from a literature review of the cost of foodborne illness due to Listeria monocytogenes in ready to eat foods. Such a study could identify and collate data provided in published material both in Australia/New Zealand and overseas. It could also provide a bibliography of publications that we can refer to and draw on in the future. If resources and time permit, this study could also report on other possible methods of evaluating the same including health economic analyses on the consequences of Listeria monocytogenes in Raw Milk.