If we were to tell you that you could lower your cholesterol and your risk of heart disease – by eating bread, would you be up for it?
It sounds too good to be true, doesn’t it? But maybe it isn’t. We’re trying to make it possible using gene technology and plant breeding techniques to develop new superior wheat varieties.
Why is cholesterol such an issue? Cholesterol is an essential type of fat that is carried in the blood. It’s vital to healthy cell function and hormone regulation, among other things, but too much of it in our bloodstream can be a bad thing – damaging our arteries and leading to heart disease. In fact, the World Health Organisation has estimated that raised cholesterol is estimated to cause 2.6 million deaths annually.
It’s no wonder our scientists have been researching foods to help lower the prevalence of cholesterol related illnesses in the community. And it looks like we’re on to something.
We know that barley and oat grains contain high levels of a soluble fibre called betaglucan (1-3 ,1-4 betaglucan), which can reduce cholesterol reabsorption in the gut. This leads to healthier blood cholesterol levels, lowering the risk of heart disease. Unfortunately, wheat (which is one of the most commonly consumed grains in the world) has low levels of betaglucan and it has a slightly different structure to the oat and barley betaglucan, which makes it insoluble.
So at the moment, it’s not possible to get cholesterol-lowering benefits from breads unless they have added barley or oat flour. This affects the taste and texture of the bread, which is why people generally prefer bread that’s made wholly from wheat flour. What we want is a bread that maximises the health benefits without sacrificing the flavour and texture that consumers want.
We now know why betaglucan in barley and oats is soluble but in wheat it’s not – and it’s to do with tiny differences between the enzymes that work in barley and oats compared with the one working in wheat to create the betaglucan. In ground breaking research just published, we’ve discovered that just one amino acid (the building blocks of enzymes) difference in the enzyme that forms betaglucan can change the structure and make it more soluble. By changing that one amino acid in the wheat enzyme we should be able to make wheat with more soluble betaglucan and cholesterol lowering properties.
In a proof of principle experiment, we used gene technology to take the gene that makes betaglucan in oats and expressed it in wheat grain. This showed we can simultaneously increase the amount of betaglucan and change its structure making it as soluble as barley betaglucan. We did this in trials using genetically modified plants, a great tool to gain knowledge. We’re using them as a small-scale means to test what’s possible and understand exactly what we need to look for when we get to the next stage which doesn’t involve genetic modification.
The trial wheat plants were grown in a controlled field trial (approved by the Office of the Gene Technology Regulator) to get enough grain to evaluate the suitability for bread-making and potential health benefits such as lowering the level of cholesterol reabsorption. If this is successful, we plan to use conventional breeding techniques to develop a wheat for public consumption. This is more difficult and will take a while longer but we think it’s possible.
This blog was originally published on the Total Wellbeing Diet website.
Fans of intermittent fasting programs – think the 5:2 diet – often find they have success with weight loss, so today we are taking a look at the pros and cons of this kind of diet.
While fasting technically refers to not consuming any food or liquid at all, intermittent ‘fasting’ diets, like the 5:2 diet, do involve very minimal calorific intake on the fasting days – we’re talking around 2000 kilojoules all day, compared to the daily recommended intake of around 10,000 for men and 8,700 for women. These diets run on the premise that you fast for 2 days of the week and consume as many kilojoules as you like on the non-fasting days.
While 5:2 is the most popular configuration, others find they have more success following a 4:3 or 6:1 ratio of non-fasting to fasting days.
The surprising news is, studies are suggesting these diets are successful in achieving weight loss. Even more surprising, Dr Manny Noakes, Research Director of our Food and Nutrition Flagship, says research is revealing people don’t eat more than they usually would on the non-fasting days – which was what many experts expected to see.
The research is still limited, but Dr Noakes says animal studies have been optimistic. Some of these animal studies have shown intermittent fasting can fend off illnesses including cancer, diabetes, heart disease and neurodegenerative disorders and may improve insulin sensitivity.
Dr Noakes says she herself would not discourage someone following such a diet that was seeing success, though she cautions there is still a lot to learn before it gets the seal of approval.
“If people who are overweight have struggled to lose weight following other diets, and they find this works for them, then that is great. Weight loss, particularly belly fat, has many health benefits – visceral fat is involved in disrupting blood-sugar regulation and is associated with high cholesterol levels. It’s also a risk factor for developing Type 2 diabetes and heart disease.”
On the flipside, Dr Noakes says what we don’t yet know about intermittent fasting is what these diets mean for long term health.
If the person is simply losing weight because they are effectively cutting a lot of kilojoules from their weekly intake, but they are still eating poorly, then I’d have to argue they still need to address their eating habits for longer term health gain.
She says while restricting your kilojoule intake is a guaranteed way to lose weight, cutting back indiscriminately can lead to an unbalanced, unhealthy diet, and recommends a more balanced approach. “It’s important not to cut key food groups including dairy, grains and cereals – you’ll be missing out on some important nutrients essential for good health.”
To summarise the pros and cons:
ON THE PRO SIDE:
- Loss of body fat/ weight for overweight people is of health benefit in general.
- Early research shows contrary to what scientists expected to see, people do not consume more kilojoules on the non-fasting days.
- Intermittent fasting diets seem to be as effective as calorie restricted diets for weight loss.
- There is early research to suggest it is effective in curbing cravings.
- It provides an easier weight loss plan than standard kilojoule restricting diets – there is no weighing or ‘forbidden’ foods to worry about – on the fasting day, the limited calories will be accounted for very quickly and there are no restrictions on non-fasting days.
ON THE CON SIDE:
- Fasting diets don’t change the way you eat – there is no evidence at this stage that suggests people eat healthier food than they did prior to starting the diet. While maintaining a healthy body weight is important for good health; a nutritious diet offers important vitamin and minerals.
- There is limited research on the long term effectiveness – or any long term health issues related to intermittent fasting.
- This lack of research means we don’t know who the diet works for and who it might not – for example, what medications or illnesses it may interact badly with.
- Unlike diets that make healthy lifestyle changes – like the Total Wellbeing Diet – fasting diets do not provide advice on how to eat for optimal health, in a way that is sustainable in the long run.
This article was written by Lucie Van den Berg and first appeared in the Herald Sun.
What came first – the chicken with the switched off allergen gene, or the allergy-free egg? Our scientists have been working with Deakin University to develop an egg that doesn’t cause allergic reactions, and it’s all about changing the chicken.
In a world first, the team has also created synthetic versions of all four egg white proteins in the lab.
Our own Dr Tim Doran, and Deakin University’s Associate Professor Cenk Suphioglu, said it was one of the first critical steps towards developing allergy-free eggs to make life easier for people with allergies and improve the safety of medications made with eggs, such as flu vaccines.
There are 40 proteins in egg white, but four major allergens that cause the majority of reactions.
Almost 9 per cent of Victorian infants have an egg allergy at 12 months of age, which can lead to dermatitis, asthma, vomiting or gut irritation.
Dr Doran, who has a daughter with such an allergy, said they were used in such a wide range of foods and products, including cosmetics and medication.
Associate Professor Suphioglu said they created all four versions of egg white proteins in the lab and switched off the allergenic response in one protein, which is responsible for the majority of allergies.
“We have developed the synthetic versions of the allergens, which are more pure and standardised than the natural extract, which would be useful for both skin-prick testing and immunotherapy,” he said.
Immunotherapy aims to give people tiny amounts of the allergen in a controlled medical setting to induce desensitisation or tolerance.
The advantage of switching off the allergenic part of the egg white protein would be that the patient would be less likely to have a dangerous allergic reaction during treatment.
Together with PhD candidate Pathum Dhanapala, the scientist’s ultimate aim is to modify the proteins in egg whites to produce chickens that lay allergy-free eggs.
Professor Mimi Tang, from the Murdoch Childrens Research Institute and Royal Children’s Hospital, said the synthetic protein could one day be useful in immunotherapy trials for allergies, but it was very early to be talking about clinical applications of the research.
“I think the major barriers to overcome with this product for it to be useful is to determine if it can be used to modulate immune responses and induce desensitisation or tolerance,” Prof Tang said.
The research is published in the journal Molecular Immunology.
By Chris Gerbing
The poor old sea cucumber doesn’t fare very well in the oceanic food chain. They’re slow-moving, (cu)cumbersome creatures that are considered a delicacy by us humans… and they even cop the brunt of Nemo’s swim up comedy routine. But they’re also an important source of income for many coastal communities around the world, particularly in the South Pacific. This is why they need to be rotated (but we’ll get to that in a bit).
Sea cucumbers, when processed and dried, are turned into bêche-de-mer, which is considered a delicacy in Chinese culture. Demand for bêche-de-mer has increased markedly in the last few decades.
The ugly cousins of the star fish are part of the benthic family of marine organisms. These bottom dwelling creatures are slow and sluggish and literally cannot move quickly enough to save themselves. That combined with their easy accessibility and high value means that sea cucumber fisheries around the world are easily overfished and many fisheries have collapsed.
In Australia, the Queensland east coast bêche-de-mer fishery is perhaps Queensland’s oldest, with harvesting starting in the mid-nineteenth century and continuing up until the beginning of WWII. A revival of the fishery did not occur until the late 1980s. With this resurgence new management systems were introduced to protect the fishery. Since then various management strategies have been implemented to align with management acts and regulations that influence this fishery.
The modern Australian bêche-de-mer fishery provides to the livelihoods of fishers from coastal communities in northern Queensland. It is typical of many small scale fisheries in Queensland and Australia in that it is difficult to do a detailed stock assessment, and hence there have been few undertaken.
This is where the rotating sea cucumbers might start to make sense.
Management agencies and industry have attempted to mitigate risk to sea cucumber populations by introducing rotational fishing zones that limit the catch, spread the activity and improve the overall sustainability of the fishery. A management strategy that humans have used on land for centuries, rotational harvesting has been less commonly applied to marine resources.
This strategy has been applied in the Australian east coast fishery and seen the creation of 154 fishing zones that can be fished for single 15 day periods every three years. Essentially, the zones are rotated…but the effectiveness of this strategy needed testing.
Research published this week by a CSIRO research team has shown that there are clear advantages to a spatial rotation harvest strategy. Using a quantitative modeling approach, the team showed that rotating the harvest zone improves the biological and economic performance of the fishery. They also found that lengthening the rotations out to six years can be helpful too.
The greatest benefit of rotational harvesting was measured for the slowest growing slugs in the sea, and also for the tastiest, who suffer under high fishing intensity.
This finding has applications for sea cucumber fisheries across Australian waters, as well as regional fisheries in South Pacific countries and south-east Asia. There are also global applications, particularly in other fisheries like abalone, geoduck clams and sea urchins that can be susceptible to overfishing.
There is potential for expansion of the Australian sea cucumber fishery in terms of both volume and value of products by spreading the fishery effort widely. We cannot say however if this will lead to sea cucumbers appearing on many local menus any time soon. But in the meantime, please keep your sea cucumbers rotating!
By John Smith
Next week Australia’s beef industry gathers in Rockhampton for their triennial shindig, the industry’s biggest — Beef Australia 2015. Over 85 000 people involved in all aspects of the industry will be there. From farmers and truckers, to agribusiness CEOs and scientists, all will share their ideas on improving the industry, an industry valued at about $6b in exports and a similar amount in domestic consumption.
Being ideas people, our scientists will be among the crowd. They’ll be sharing what we’re working on, and laying out the opportunities for farmers and others. We’ll show how science can be used for a more productive, profitable and sustainable industry.
We’ve been helping the beef industry for as long as we’ve been around. Many of our advances go to show how innovative our farmers are, ready to take on new practices and technologies.
In one end, and out the other: Dung beetles, cow burps, and gut microbes.
Where to start? Perhaps at the end? Did you know we’re the one’s who brought in dung beetles to Australia to deal with, well, the dung? Indeed, and that’s why you’re sucking in air right now and not pesky bush flies.
At the other end we’re helping understand methane emissions from burping cattle, which along with sheep accounts for about 10% of Australia’s greenhouse gas emissions. Using some innovative techniques, including the use of lasers, we can measure the emissions from cattle in different environments and on different diets. We recently figured out the cattle in northern Australia on certain grasses emit about 30% less methane than previously estimated, so we’ve worded up the IPCC to correct the record on Australia’s emission estimates.
We’re also investigating end to end to understand the mechanisms involved with methane production, such as gut microbiota, and looking to the likes of Australia’s grass eating marsupials for ways to help reduce greenhouse gas emissions and improve conversion of feed to meat.
Bovine 2.0: Breeding for the wide brown land
Early in our days it was recognised that the predominant European Bos taurus cattle breeds weren’t really suited to conditions in northern Australia. Heat, ticks and other parasites took their toll. We crossbred the Bos taurus cattle with Bos indicus cattle, from Texas, to produce some improvements in tolerance to the tough conditions. Though many weren’t impressed with us “mongrelising” their European breeds, their minds were changed when our new crossbreeds survived the 1930 drought. Overall, out breeding programs have brought in an estimated $8 billion to the industry.
We teamed up with international partners in the early 2000s to sequence the bovine genome. This genetic research has gone into both BREEDPLAN, Australia’s National Beef Genetic Evaluation Scheme, and GeneSTAR, a test for a range of genetic markers associated with meat quality and desired production traits.
Don’t hurt a cow, man: Cow welfare
We identified a genetic marker for ‘hornlessness’. Horns are a big problem for industry. Horns hurt handlers and other cattle and removing them is hard on both animals and farmers. A poll gene test is now helping farmers select cattle that are much more likely to breed hornless offspring providing both production and welfare benefits.
We also continue to help the industry meet high standards of animal welfare by providing objective assessments of new pain relief options and mitigating the impact of long distance transport both on land and at sea.
McDaisy: taste and tenderness assessments
Of course all of this great performing cattle isn’t much good if it doesn’t taste good so researchers, including our scientists, worked with Meat & Livestock Australia to develop Meat Standards Australia – an objective assessment of meat for eating quality that takes the guess work out of choosing a great cut of meat, be it at the supermarket or restaurant.
Speaking of delicious, we’ve investigated ways of using High Pressure Processing to tenderise otherwise low-value cuts that also provides three times the normal shelf-life. This continues a long tradition of post-farm gate research for the cattle industry. We previously worked on refrigerated and frozen meats for long distance shipping, opening and expanding many export markets.
Mad cow, sane science: Defence against microbes
Along with our research into cold storage, our food safety scientists are using an enhanced understanding of food borne bacteria such as E. coli to ensure continued access to export markets such as the US without elaborate import testing regimes.
Meanwhile, north of Australia we’re helping keep serious biosecurity threats like foot and mouth disease at bay by working with South-East Asian countries to improve their surveillance and response to diseases that could damage our cattle industry and greatly hinder market access. Similarly, in Australia, we’re helping industry and government prepare for the next disease incursion.
As you can see, there is plenty of great Aussie ingenuity that goes into creating some of the most sustainable and salivatory beef in the world. So next time you’re chewing over a beef burger, take some time to ruminate on the contributions we’ve made to the beef industry in the last 90 years.
Anzac Day is a time for honouring our soldiers, eating Anzac bikkies and enjoying a couple of cold bevies while watching the Footy. For Australian wheat farmers, Anzac Day also marks the important start to the sowing season, with late April through to May having long been accepted as the optimal time for sowing wheat in Australia.
But now our research is questioning this common logic. In fact, a team of our scientists in the Agriculture team are now recommending sowing earlier; any time from early April onward.
They’ve been trialling early sowing around southern Australia, and the results were staggering. By including early sown wheat in cropping programs, yield was increased by an average 13-47 per cent across all regions.
Why would sowing earlier lead to higher yields?
Rainfall is critical for the establishment of the mid to fast growing wheat varieties currently popular with Australian farmers and autumn’s historically good sowing rainfall allows the flowering of cereal crops to occur at the best possible time. This is vital to yield and, subsequently, a farmer’s profit.
But a changing climate, declining autumn rains and more extreme spring weather means that conventional sowing times are no longer ideal. Farmers waiting until Anzac Day to sow may miss the best opportunity to get the highest yield.
So we’ve been looking at ways to do things differently.
While our grain researchers were pondering the challenge of maximising farm water efficiency, (research that won them a Eureka prize in 2014) they began considering crop-sowing strategies that would use the increasing summer and early autumn rainfall to establish wheat crops earlier. After all, the idea is to get as much of the wheat crop as possible to flower during the optimal period.
And it’s not enough for farmers to just start sowing their crops earlier because the early sowing of currently popular varieties of fast-maturing wheat presents a different problem: fast maturing wheat, matures, well… fast. This makes the risk of frost damage occurring during flowering stage likely, as fast maturing wheat sown in early autumn will flower right about the time night air starts dropping below a frosty two degrees Celsius.
Frost damage reduces grain quality and yield, so to navigate this challenge the team of researchers needed a solution. The answer is the rarely used, slow-maturing ‘winter wheat’ which can account for this issue.
Farming is an art and knowing the optimal flowering window is key to getting the best yield. So it isn’t enough for farmers to start sowing in early April, for the best results we recommend combining crops – beginning with winter wheat sowing in early April, and then staggering regularly used mid to fast maturing crops at ten day intervals.
This is great news for farmers: not only do they produce a bigger yield of wheat and improve their farm’s sustainability and profitability, but with the pressure off to sow their entire allocation around April 25, they may even find time to take part in the dawn service and watch the Anzac day clash!
You can read more about Dr Hunt’s research here: Optimising grain yield and grazing potential of crops across Australia’s high rainfall zone: a simulation analysis
This research is funded by the Grains Research and Development Corporation (GRDC)
By Dr Narelle Fegan and Dr Andrew Leis
Keeping our food safe
The recent outbreak of hepatitis A, which is thought to be associated with the consumption of frozen berries, has highlighted food safety concerns and sparked debates around country of origin labelling and testing of imported foods. Ensuring the safety of our food supply can be a complex process that involves maintaining good hygienic practices in the production and handling of foods at all stages between the farm and consumption.
With some foods, we can reduce the risk of foodborne illness through a heating process, which includes practices like cooking, canning and pasteurisation. However, with fresh produce (such as leafy green and fruits), a heating step is less desirable – we have to rely more on hygienic production to deliver a safe food product. There are quality assurance schemes in place to ensure that fresh produce is grown, harvested, packed and transported to limit contamination by foodborne pathogens.
These schemes rely on people involved in all parts of the production chain following the procedures outlined, to deliver a product that is safe to consume. Such quality assurance schemes operate across the globe and imported products are required to meet the same hygienic standards as food produced in the importing country.
Can testing of food ensure it is safe to eat?
Microbiological testing of foods is only one aspect of quality assurance schemes designed to help keep our food safe. Scientific evidence and history tells us that testing of products for pathogens is not an efficient way of determining if food has been contaminated.
This is particularly true of pathogens that occur very rarely in food (such as hepatitis A) as only a very small amount of the food will be contaminated, and we can’t guarantee we will sample the portion of food where contamination occurs. The difficulties associated with pathogen testing of foods include:
- Contamination is not evenly distributed within the food and only certain portions of the food may contain the pathogen.
- Testing for foodborne viruses destroys the portion of food that is tested.
- Because the food is destroyed during testing, not all of the food can be tested as there would be nothing left for us to eat. Only some of the food can be tested – but sampling plans have been developed to try and maximise the chances of detecting foodborne pathogens.
- Testing methods for foodborne viruses in particular can be difficult to perform, as we have to try and isolate viruses and their genetic material from foods which are often very complex in nature (containing fats, sugars and salts, which can all make it more difficult to detect pathogens).
For these reasons testing of food is only one part of quality assurance schemes, with more attention focusing on hygienic production to limit the opportunities of food becoming contaminated with pathogens.
Why would frozen berries be at risk of carrying hepatitis A?
Freezing is a highly effective and convenient way to increase the shelf-life of foods, and unlike heat-based sterilisation techniques, it preserves most of the nutritional value of the food (some components, like vitamins, are quickly destroyed by heat). Freezing not only prolongs shelf life but also allows us to enjoy very seasonal products, such as berries, at any time of the year.
Preservation of viruses and bacteria during freezing is affected by the rate of freezing and the amounts of sugars and other molecules nearby that help to slow the growth of ice crystals. In a household freezer, water freezes quite slowly – consider the time it takes to freeze water in ice cube trays. Slow freezing favours the formation of ice crystals. As the crystals grow in size, they can kill some bacteria and viruses. On the other hand, high local concentrations of sugars and other molecules can protect the microorganisms from damage.
Frozen berries are generally safe to eat, and have only occasionally been involved in foodborne outbreaks. Hepatitis A virus infection as a result of eating contaminated food (not just berries) is also very rare, particularly in Australia where on average only five cases a year are associated with food consumption in Australia. This is very small compared to other foodborne pathogens in Australia such as Norovirus, where an estimated 276,000 cases a year are associated with food and bacteria, or Campylobacter where 179,000 cases are associated with the consumption of food.
What can we do to ensure the food we eat is safe?
It is not possible to ensure safety by testing a final product. Therefore, systems based on hazard analysis and identification of critical control points have been developed and adopted by governments and food producers through food regulations, industry guidelines and quality assurance schemes. However, human error through poor planning or poor execution can lead to one or more failures along the supply chain. The best thing we can do to ensure the food we eat is safe is to foster a culture of food safety. This means better educating all those involved in the food industry, as well as governments and consumers, so that they understand the safety risks associated with the production, manufacture and consumption of foods.Food safety needs to be seen as an investment, not a cost.
For more information, visit our website.