Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Edible coatings will be the packaging of the future

05.09.2006
The growing demand by consumers for healthier and more ecological foods has driven researchers to develop new systems of packaging that prolong the useful life of the products and that are, at the same time, recyclable. Protection is currently carried out with a mixture of synthetic chemical compounds that are not completely biodegradable. One of the most popular alternatives in the last few years is the edible coating – a transparent film that covers the food item and acts as a barrier to humidity and oxygen. Moreover, these films can be used as a host for additives in the conservation of the properties of the product or simply in order to improve its appearance.

This was the subject of the PhD thesis by Navarre chemist, Javier Osés Fernández, at the Public University of Navarre. In the research, various edible coatings were analysed – all based on proteins extracted from milk serum (whey protein isolate or WPI), mesquite gum and starch - with the objective of evaluating their possible food applications.

The PhD, entitled “Development, characterisation and applications for foodstuffs of edible coatings based on milk serum proteins, starch and mesquite gum”.

Mesquite gum, an efficacious and cheap solution

... more about:
»Conservation »PhD »WPI »humidity »mesquite

To test the efficacy of the edible coatings compared to synthetic packaging, Javier Osés prepared a number of samples of milk serum protein films, of mesquite gum and of starch, and stored them for six months at different humidity levels.

The first conclusion from the study is that, depending on the type of plastifier used, the mechanical properties change with the passage of time. Thus, those films with sorbitol plastifier underwent variation in their mechanical properties, i.e. their flexibility; while those containing glycerol did not alter their composition. Once the ideal plastifier for the coating was determined, it was observed that, in order to improve malleability, it was necessary to introduce a lot of glycerol. However, using high quantities of plastifier in a coating results in an increase in its permeability to water vapour, and its applications are thus very limited. In order to set this deficiency off, mesquite gum was incorporated into the milk serum protein. This is a polysaccharide that grows in dry and semi-arid regions of the north of Mexico. The result is a compound film that is resistant and that maintains suitable mechanical properties. The use of mesquite gum is an economical and efficacious alternative with a promising future, not only for food conservation, but it could also become an economic resource for indigenous peoples, currently marginalized, as well as having the effect of reducing the desertisation of the soil.

The edible coating of fruit is currently the best-known example of the application. However, it is a packaging system particularly efficacious for conserving foodstuffs that are high in polysaturated fatty acids, susceptible to oxidation, such as nuts, meat and certain fish such as salmon.

In his PhD, Javier Osés evaluated to what extent the edible films which he had developed were able to protect fatty foods. To this end, he used a model foodstuff – sunflower oil. In a first stage, trials were carried out with WPI coatings. Results showed that the protection capacity of the film depended on the amount of plastifier in the film, on its thickness and on the relative humidity of storage of the foodstuff. Thus, the most efficient WPI films were those of greater thickness, with less amount of plastifier and that had been exposed to low relative humidity.

The second stage involved a similar experiment, but with films made of starch, known to be an efficient barrier to oxygen, and with which trials were undertaken. In this case, the thickness of the film did not influence the protector effect on the oil, but it was shown that starch films are more effective in ambiences with high relative humidity.

The final part of the PhD outlined the application of edible coatings with WPI on chicken breasts. The aim was to analyse the effect on their aspect and their properties. At the same time, the experiment was used to incorporate nisine, an antioxidant agent that penetrates the foodstuff little by little and thus offers an ongoing protection. The idea was to extend the conservation time for a chicken breast would go from the current 7 days to 15, but the results were negative. However, a very interesting line of research was opened as it has been shown that the coating formed a second skin on the breast and onto which various additives, such as antimicrobians, can be added

Despite the fact that the coatings did not manage to reduce microbian evolution, it has been shown that the WPI forms a film on chicken breasts which is homogeneous, transparent, has good adhesion and is not easily perceived by the naked eye.

The future of packaging

Currently, the three systems of conservation most used by the food industry are vacuum packing, nitrogen sweeping and aluminium foil. The Pamplona research chemist holds that WPI films are the packaging of the future, although the commercial exploitation of the application is yet to materialize. There are many possibilities – on the one hand, they will prolong the useful life of foodstuffs in a healthy way and, on the other, they will be very beneficial for the environment given that they will reduce the use of plastics.

Despite the advantages presented by the experts, there exists a number of obstacles to the full development of this alternative system. The main one is that of cost. As edible coatings are still in the research stage, enterprises do not have the technology needed to apply the system. For the moment, its current use is restricted to products with high added-value. This is why, amongst the most immediate projects of the research team from the Food Technology Area at the University, is the application of edible films to turrón (sweet nougat), in order to eliminate the aluminium foil currently used to protect it and so that the product would have only one protective coating. This project is still in the study phase.

Irati Kortabitarte | alfa
Further information:
http://www.basqueresearch.com

Further reports about: Conservation PhD WPI humidity mesquite

More articles from Life Sciences:

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

nachricht Antimicrobial substances identified in Komodo dragon blood
23.02.2017 | American Chemical Society

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

NASA eyes Pineapple Express soaking California

24.02.2017 | Earth Sciences

New gene for atrazine resistance identified in waterhemp

24.02.2017 | Agricultural and Forestry Science

New Mechanisms of Gene Inactivation may prevent Aging and Cancer

24.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>