Overweight world eyes lupins
An urgent need to address the global ‘diabesity’ pandemic highlights the potential for Australian lupin growers and processors – if food technology can deliver a commercial product.
High in protein and fibre with a low glycaemic index, the lupin could be the “next big thing” according to Australian researchers uncovering the legume’s potential as a functional food able to help prevent and manage obesity and diabetes.
Studies at the Centre for Food and Genomic Medicine (CFGM), based at the Western Australian Institute for Medical Research (WAIMR), have shown that the Australian sweet lupin suppresses appetite, reduces the glycaemic load of carbohydrates, improves insulin sensitivity and lowers blood pressure – effects crucial to averting a looming global diabetes crisis.
The pulse languishes as a low-value feed grain, yet its potential for human nutrition is considered to be immense, given the need for high-protein, plant-based products to rebalance modern diets that have become overloaded with sugars and carbohydrates.
The incidence of diabetes has more than doubled worldwide in the past 30 years, with the number of diagnoses expected to jump from 370 million to 500 million by 2030.
The forecast has prompted the United Nations World Health Assembly to call for a 25 per cent reduction in avoidable death from non-communicable diseases, including diabetes, by 2025.
In the Medical Journal of Australia last August, Baker IDI Heart and Diabetes Institute director Professor Paul Zimmet reported that more than 1.5 million people in Australia have diabetes, and two million are pre diabetic.
The looming health predicament underlies CFGM hopes to build support for a national research effort. The CFGM was established in 2006 with $4.5 million seed funding from the WA Government. It brought together scientists from the biotechnology, medical research, agricultural and food technology sectors to tackle ‘diabesity’.
Funding expired 18 months ago but WAIMR’s Dr Carolyn Williams says lobbying will continue for research that can determine how to incorporate lupins into diets through new food products and/or substitutes for existing products.
She says that increasing the dietary intake of both protein and fibre can be difficult because popular low-carbohydrate and high-protein diets have low fibre content.
However, lupins comprise about 40 per cent protein and 30 per cent dietary fibre, have little or no starch and are low in oil – a combination that could create a dietary defence against the obesity, high blood pressure, high cholesterol and insulin insensitivity synonymous with ‘diabesity’.
Introduced to Australian cropping – particularly in WA – to fix soil nitrogen, lupins are predominantly sold as stockfeed but the consumer health market looms as the goal to chase.
Australia is already the world’s largest producer (85 per cent) of narrow-leafed lupin (Lupinus angustifolius), also known as Australian sweet lupin.
WA alone is responsible for 80 per cent of the world’s lupin production and is the major exporter of lupin grain, producing up to one million tonnes each year.
Dr Williams says lupins are an excellent source of bioactive compounds, which render the legume suitable for the functional foods* market. “Our clinical research supports this claim and we are keen to identify the exact components that convey these benefits,” she says.
“Lupins are also gluten-free, have a higher concentration of essential amino acids – particularly lysine – than other pulses, and are a high protein substitute for meat.
“Lupins’ health advantages and prevalence in Australia provide substantial value-adding opportunities for growers and processors, but development of commercially viable food products with high consumer acceptance is paramount,” Dr Williams says.
“[Lupin] flour must be affordable and the products must be appealing and cost-effective to reach the mass market.”
Backed by the GRDC, CFGM scientists have mapped the narrow-leafed lupin genome to understand its genetic blueprint and determine how the legume can be grown more successfully as a healthy human food.
The study findings have also identified candidate genes for agronomic traits such as drought tolerance and disease resistance to improve breeding programs and increase profitable production.
“While lupin is a great break crop, it is not as profitable as canola, but we are confident more growers across Australia would make the shift if they received higher prices driven by increased consumer demand,” Dr Williams says.
“Lupin Foods Australia – a subsidiary of the CBH Group – is keen to focus on lupins for [human] food rather than [stock] feed and to break the nexus between food and feed.”
Dr Carolyn Williams,
0417 432 184
Centre for Food and Genomic Medicine,
* Functional foods are foods that have been fortified with health-promoting additives.
GRDC Project Code UWA00147