Researchers from the Department of Food Science at the University of Wisconsin used the Alcalase enzyme (from Bacillus licheniformis) to produce hydrolysed collagen peptides derived from bovine gelatin. The new protein reportedly binds to the surface of ice in the ice cream, and prevents the growth of ice crystals.
“One of the major advantages of collagen-derived antifreeze peptides is that unlike other natural anti-freeze proteins, the antifreeze activities of collagen peptides are not destroyed by thermal treatments,” wrote ShaoYun Wang and Srinivasan Damodaran in the Journal of Agricultural and Food Chemistry.
The research taps into ongoing innovation in ice cream formulation. Only recently Unilever was granted EU novel foods approval for the ingredient ice structuring Protein (ISP), used in ice cream to reduce fat content and improve stability.
The ISP ingredient, already used in products markets such as the US, Australia and Mexico, can reportedly help reduce the fat and calorie content of products by up to 50 percent. Its ability to improve the stability of ice cream also allows for a higher fruit content, an improved taste, better structure and slower melting, claims Unilever.
Damodaran reported initial advances in this field in 2008. The new study details the partial characterisation of ice-structuring collagen peptides derived from Alcalase (from Bacillus licheniformis) hydrolysis of bovine gelatin provided by St. Louis Food Ingredients.
The peptides were able to “inhibit recrystallisation of ice in frozen ice cream mix as well as in frozen sucrose solutions in a manner similar to natural antifreeze proteins”, wrote the researchers, with the optimal performance noted for collagen peptide fractions in the molecular mass range of 600-2700 Da.
Specifically, cationic collagen peptides with molecular mass ranging from 1600-2400 Da were more effective than the anionic peptides in inhibiting ice crystal growth.
“Although isolation and structural characterization of collagen peptides showing high antifreeze activity remain to be studied, it is likely that the mechanism of inhibition of ice recrystallisation by these collagen peptides might be similar to that of the snow flea antifreeze protein,” wrote the researchers.
According to a Euromonitor study companies in the ice cream market need sensitivity to changing regional tastes, exotic flavour mixes, labelling and packaging to be successful in attacking Western Europe's stagnant ice cream market
Sales of ice cream decreased by 0.4 per cent to US$20.3bn in 2004 in the region, according to Euromonitor. Processors are focusing on introducing unusual flavors and premium brands to hold on to their market shares.
Source: Journal of Agricultural and Food Chemistry
Published online ahead of print, Article ASAP, doi: 10.1021/jf900524y
"Ice-Structuring Peptides Derived from Bovine Collagen"
Authors: S.Y. Wang, S. Damodaran