The study, published on-line in the journal Food Chemistry, weighs into the hot topic of acrylamide reduction in fried foods, and supports the efficacy of Novozymes' Acrylaway derived from Aspergillus oryzae, launched last year.
"Asparaginase just right now is commercially available and it is sold today," wrote lead author Franco Pedreschi from Universidad de Santiago de Chile (USACH).
"The enzyme can be reused in other batches which will bring down enzyme dosage per kg final product, and thereby also costs.
"The content of asparaginase in the solution is low meaning that the total protein load of the water will not affect the overall quality of the process waste water."
Acrylamide is a suspected carcinogen that is formed during by heat-induced reaction between sugar and an amino acid called asparagine. Known as the Maillard reaction, this process is responsible for the brown colour and tasty flavour of baked, fried and toasted foods.
The problem was discovered in 2002 by scientists at the Swedish Food Administration.
At the tail-end of 2007 the Confederation of the Food and Drink Industries of the EU (CIAA) included asparaginase in the new version of its Acrylamide Toolbox, a move seen to validation the efforts of companies that have developed commercial solutions using the acrylamide-reducing enzyme.
The latest update included the feasibility of the enzyme asparaginase in production of biscuits on an industrial scale. This is an area that has seen much heated activity this year as both DSM Food Specialities and Novozymes have commercial products aimed at this area.
Both DSM's Preventase and Novozymes' Acrylaway are asparaginases, but they stem from different production strains: Novozymes' from Aspergillus oryzae and DSM's from Aspergillus niger.
The two enzymes are understood to share the same aim - that is, to convert free asparagine into aspartic acid, another animo acid that does not form acrylamide. The nutritional properties are unaffected, and so are the browning and taste aspects.
The new study used Novozymes' Acrylaway for the production of French fries. The potatoes were cut into strips, blanched, dried and partially fried. Control strips were not blanched but dried and partially fried. Both sets of strips were then treated with a 10,000 ASNU/l asparaginase solution and the frying process completed.
Pedereschi, in collaboration with researchers from the University of Aarhus (Denmark), and the Technical University of Denmark, reports that treating the control strips with the solution reduced acrylamide formation by 30 per cent, while the blanched strips contained 60 per cent less acrylamide at the end of the frying process.
"Soaking of blanched potato strips (75 °C, 10 min) in an 10,000 ASNU/l asparaginase solution at 40 degrees Celsius for 20 minute is an effective way to reduce acrylamide formation after frying by reducing the amount of one of its important precursors such as asparagine," wrote the researchers.
Commenting on the research, Thomas Erik Nilsson, global product launch manager for Acrylaway, told FoodNavigator.com: "The issue of acrylamide relates to a range of different food categories, including French fries and this is why the Chilean-Danish study is important.
Novozymes has obtained industrial proof that Acrylaway reduces acrylamide by 50-85 per cent in various food categories, including several baked goods and snacks.
More than two years ago, Novozymes offered samples of Acrylaway and process recommendations to the Chilean-Danish study. The outcome of the study confirms our test results with French fries and underscores Acrylaway as one of the most promising technologies for efficient reduction of acrylamide.
While the Chilean-Danish study was underway, Novozymes was busy improving the economy and the industrial applicability of the acrylamide-reduction process with Acrylaway. We have made major improvements to increase the speed of the process, which I believe will be very well received by the industry.
We believe that Novozymes has the technical solution that reduces acrylamide by 50-60 per cent in the industrial production of French fries. The implementation in the industry has shown that cost-in-use still needs to be fine-tuned. However, we expect to finalize this work together with the industry, so that cost-efficient acrylamide reduction is also possible with French fries."
Source: Food Chemistry (Elsevier)
Published on-line ahead of print, doi: 10.1016/j.foodchem.2007.12.057
"The effect of asparaginase on acrylamide formation in french fries"
Authors: F. Pedreschi, K. Kaack, K. Granby