Writing in Journal of Agricultural and Food Chemistry, the researchers based at the Beijing University of Chemical Technology, report a new method for creating large quantities of fermentation-derived gelatine which they say could, in theory, become a substitute for animal-based gelatine currently used in many food products.
The researchers, led by Jinchun Chen from Beijing University, successfully produced the alternative by genetically engineering yeast cells to produce that same version of the of the gelling agent that humans naturally produce.
Public perception
A report by US-based Global Industry Analysts (GIA) recently highlighted public concerns regarding use of animal-sourced gelatine – and the rise of vegetarian and vegan alternatives – means industry will likely to see a shift away from the use of animal-derived gelatine.
The GIA report noted that the global gelatine market is growing fast, driven by increasing demand for gelatine for food production in developing countries and as a biomaterial in cosmetics.
“Processors are already seeking substitutes for animal-sourced ingredients. While these alternatives meet some gelatine characteristics, none is yet available that matches all the functions such as gelling, binding, thickening, stabilizing, film forming, and aerating properties,” said the GIA.
Practical issues
Gelatine is widely used as a gelling agent in many industries, including pharmaceuticals, cosmetics, and particularly in the food industry, because of its unique properties.
“The current methods of making gelatine involve the extraction of collagen from animal tissue (skin and bone of bovine or porcine) and its conversion to gelatine, which is later isolated by acid, base, or enzymatic extraction methods,” said the researchers.
Chen and his colleagues noted that that from a functional point of view, gelatine produced from animal sources are often mixtures of polypeptides of different sizes and charges – meaning that the products can vary greatly and have severe effects on gel-forming capacity.
In addition, they said that animal-sourced gelatine will always carry a risk of associated infectious diseases, such as bovine spongiform encephalopathy, and can also cause immune hypersensitivity when consumed by humans.
Useful alternative?
“On the contrary, production of human gelatine in a microbial expression system may eliminate the aforementioned problems because the size and charge of human gelatine can be easily controlled,” said Chen and his team.
“Moreover, scaling up production of the desired product by DNA manipulation and bioengineering-related techniques in microbial expression system is feasible … These advantages of recombinant gelatine have attracted increasing interest from research and industrial circles,” they added.
By inserting human gelatine genes into the yeast strain Pichia pastoris, using genetic engineering techniques, the cells are then able to produce the ‘human’ form quickly and efficiently.
Chen and his team also noted that the human-yeast gelatine is more stable than animal-based gelatine, which can have a high variability from batch to batch – meaning the new method may offer greater quality control on the production line.
Source: Journal of Agricultural and Food Chemistry
Volume 59, Issue 13, Pages 7127–7134, doi: 10.1021/jf200778r
“New Strategy for Expression of Recombinant Hydroxylated Human-Derived Gelatin in Pichia pastoris KM71”
Authors: H. Duan, S. Umar, R. Xiong, J. Chen