The study, published in Food Hydrocolloids, investigated the effects of heat treatment on the ability of collagen fibre to act as an emulsifying agent.
“The results of this work allowed for the elucidation of some of the effects of the heat treatment and homogenization pressure on the emulsion stability, structure and rheology,” said the authors, led by Rosiane Lopes da Cunha from University of Campinas (UNICAMP), Brazil.
Collagen
Collagen is already used by the food industry as a protein and collagen fibre as a water and fat binder in meat products. But the broader potential of collagen fibre as an emulsifier, obtain from crude collagen and defatted, dried and ground, is a new area of exploration.
da Cunha and her colleagues explained that a number of ingredients obtained from collagen, such as gelatin and collagen fibre, may also have applications for the food industry.
“Collagen fibre is a new ingredient obtained from collagen in its crude form,” wrote the authors. They explained that previous research has suggested that collagen fibre has potential for use in the food industry as a natural, food grade, emulsifier,
The new study investigated the effects of heat treatment on the emulsifying properties of collagen fibre.
Study details
The emulsifying properties of collagen fibre were modified by heat treatment at temperatures ranging from 50 to 85 °C for 20 or 60 minutes. In addition to heat treatment, the influence of pH and the emulsifying process were evaluated on oil-in-water emulsions stabilized by collagen fibre.
da Cunha and her co-workers found that changes in collagen fibre structure from heat treatment were not sufficient to improve its emulsifying properties.
They observed the heating process to decrease protein charge and increase solubility in water, “which probably decreased the oil/protein interactions,” they suggested.
They reported that alkaline emulsions showed greater instability than acid emulsions; explaining that the net charge of collagen fibres is lower at high pH values.
“Acid emulsions produced by high-pressure homogenization showed high stability, with similar droplet size under various conditions of homogenization pressure […] and composition of the heat treated protein,” said the researchers.
The researchers concluded that heat stabilised collagen fibre shows good potential for use as a natural emulsifier for the food industry – mainly in acid products.
Source: Food Hydrocolloids
Published online ahead of print, doi: 10.1016/j.foodhyd.2011.04.006
“Emulsions Stabilized By Heat Treated Collagen Fibers”
Authors: R. de Castro Santana, A.C. Kawazoe Sato, R.L. da Cunha