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As a result of work carried out by a butcher from Mindelheim and scientists from the Fraunhofer-Gesellschaft applied research organisation, tasty sausage varieties containing on 2-3 per cent fat are now a reality. And the almost fat-free sausage is starting to make its way onto the refrigerated shelves of German shops.
Mindelheim master butcher Josef Pointner originally hit on the idea of a low-fat sausage. "Low-fat products for varieties such as ham sausage, Leberkâse (a German meat loaf specialty), or salami, or Weisswurst (Bavarian veal sausage), have never been available until now. But I was only partially successful in producing these sausage varieties."
Fraunhofer scientists were able to help. They found that the trick is to replace the fat in the sausage by proteins. For this to work, however, the proteins in the meat need to become more closely cross-linked. In other words, they must unfold their structure in such a way as to bind as much water as possible.
"Everything depends on the cutter, a bowl that revolves around a set of sharp rotating knives. All the ingredients are combined in this bowl: lean meat, spices and ice. In conventional cutters, the knives can reach peak temperatures of up to 75°C. This causes denaturation of the proteins, which then form unwanted small lumps in the sausage-meat and partly lose their ability to bind water," explains Peter Eisner of the Fraunhofer Institute for process engineering and packaging.
Nevertheless, a series of tests were carried out at the Institute's own sausage plant to achieve the ideal fat content and the right consistency of the sausage-meat.
"The secret is to monitor the temperature and to keep on cooling the cutter knives and the sausage-meat. Perfect timing is the crucial factor here. Just one moment too late, and the knives will get hot," added Eisner.
Fraunhofer and Pointner hold the patent for this manufacturing process, but because of a confidential agreement signed with an industry partner were unable to provide eFood with any extra technical detail about what is involved (Fig.1).
Crisp wieners, succulent ham sausage and suchlike are very popular in Germany, where about 1.5 million t/y of sausages and meat products are consumed.
Two-thirds of these are hot or cold boiled sausages. But these varieties usually contain a great deal of fat to ensure that they have the right consistency and taste good. Varieties sold until now as low-fat sausage may contain as much as 20 per cent fat. Even very lean poultry-meat sausage is fatter by comparison.
Which is why Ulrich Buller, professor and senior vice president of research planning at the Fraunhofer-Gesellschaft, is keen to highlight the importance of the new VielLeicht low-fat sausages: "Fraunhofer know-how has gone into this low-fat sausage. Our scientists are researching to benefit real people. In this case they have co-operated with a small enterprise to develop lean sausage varieties for health-conscious consumers."
Good for prostates too
Buller's emphasis on the health benefits of lean sausage meat is being borne out by the latest research from the Fred Hutchison Cancer Research Centre in Seattle, US, too.
It is well established that men who eat a diet low in fat and red meat but high in vegetables and lean protein and who drink alcohol in moderation are doing their hearts a favour. However, this new study shows that such a heart-healthy diet may also be good for the prostate.
Specifically, such a diet significantly decreases the risk of symptomatic benign prostatic hyperplasia (BPH). This condition is associated with frequent and painful urination that affects about half of all men by the time they reach 50 and nearly all men by age 70.
The researchers, lead by Alan Kristal, have published their findings online in the American Journal of Epidemiology. They found that a high-fat diet increased the risk of benign enlargement of the prostate by 31 per cent, and that daily consumption of red meat increased the risk by 38 per cent.
The study also found that eating four or more servings of vegetables daily was associated with a 32 per cent reduction in risk, consuming high amounts of lean protein (about 20 per cent of daily calorie intake) was associated with a 15 per cent risk reduction, and that regular, moderate alcohol consumption (no more than two drinks a day) was associated with a 38 per cent decline in BPH risk.
"It is known that obesity increases the risk of BPH. The dietary pattern that is associated with obesity among men in the US is high fat consumption. The results of this study clearly show a link between a high-fat diet and increased risk of BPH," said Kristal, member and associate head of the Cancer Prevention Programme in the Public Health Sciences Division at the Hutchinson Centre.
Prostate enlargement puts pressure on the urethra, which makes it difficult to empty the bladder completely, which in turn results in the frequent urge to urinate. BPH is also associated with constant contraction of the prostate gland's smooth-muscle tissue, which also puts pressure on the urethra.
The mechanisms behind excess fat intake and increased risk of BPH are not clearly established, but likely factors include chronic inflammation and changes in steroid hormones.
"We don't really know how it's working but it's pretty clear that eating a high amount of fat - and it doesn't appear to matter what kind of fat - increases the risk of BPH," Kristal said.
The study found small, incremental increases in BPH risk as fat intake increased, with the most substantial risk - more than 30 per cent - among men who got about 40 per cent of their calories from fat.
High fat intake increases the body's overall inflammatory response and it also increases levels of circulating hormones such as estrogens and androgens, he said, both of which may affect prostate tissue.
In contrast, a low fat, high vegetable and moderate alcohol consumption pattern is associated with less obesity, lower circulating estrogens and androgens and less stimulation of the sympathetic nervous system.
"It is possible that these physiological effects moderate both the hormonally regulated prostate growth and heightened smooth-muscle tone that cause BPH," the authors wrote.
The mechanism by which moderate alcohol consumption appears to protect against BPH may be due to its effects on the production and metabolism of testosterone, Kristal said. Moderate alcohol use lowers circulating hormones and decreases muscle tone of the prostate.
Few studies to date have examined dietary patterns and BPH risk, and most have been small and have collected very limited data.
For the current study, Kristal and colleagues assessed diet, supplement use and alcohol consumption in 4770 men for seven years, 876 of whom developed symptomatic BPH.
They collected the data in the context of a larger randomised clinical trial that aimed to determine whether finasteride, a drug used to treat BPH, would also prevent prostate cancer.
The men involved in this analysis, all 55 and older, participated in the placebo arm of the finasteride trial. All were free of BPH symptoms at the start of the study and received annual screening for signs of prostate enlargement.
"Being able to study men in the placebo arm who weren't taking finasteride allowed us to look at factors other than finasteride to predict BPH risk," Kristal said.
The study found no evidence that specific supplements, such as antioxidants, zinc or calcium, were associated with reduced risk.