The main objective of the project is to make high performance gelatins from alternative sources or from blends of commercial gelatins and gelatins from alternative sources. These gelatins from alternative sources will be studied and compared to commercial gelatins. The structural properties are to be related to functional properties. This information will be used to broaden the use of gelatins by:
- Study the formation and structure of different mammalian and fish gelatin gels.
- Study functional properties of different mammalian and fish gelatins.
- Evaluate the structure-function relationship of gelatins by comparing structural and functional data and by using the latest methodologies in the area.
- Making and evaluating blends of the new gelatins and commercial gelatins.
- Modelling of functional properties.
State of progress
The work started officially the 1st of September 1997 and is on schedule. The main work has been done in Task 1 as planned in Annex I.
The work has started on 12 different samples of gelatin from fish (cod, megrim and tilapia) and mammalian from beef and pig (hides and bones). The gelatins are also differentiated by the production process that is either alkali or acidic and also if the gelatins are high molecular weight (HMW) or low (LMW). These gelatins give a wide range of different properties. The structural and functional measurements are performed according to the plan set out in Annex I as well as all supporting analysis. The gelatins were first prepared at the laboratories of four different partners and then send to each participant. Now the samples are analysed and measured with the methodologies as mentioned above, first in their natural state and then later were factors such as pH, ionic strength, concentration and temperature are varied.
The result indicate that the HMW gelatins develop higher amount of helices during cooling of the gelatin solutions. Molecular weight seems also to be single most important factor in viscosity as HMW gelatins give higher viscosity of solutions. The amino acid compositions seems also to be most important factor that influence the gel formation (Tg) and melting (Tm) temperatures of the gelatins. The fish gelatins from cold water have very low Tg and Tm and are also very low in hydroxyproline and proline content but mammalian gelatins have the highest values. Within the same type of gelatin the HMW gelatins have higher Tg and Tm than LMW gelatins.
V. Future actions
The plan of Annex I will be followed with minor changes that have been agreed at project meetings and concerns division of work and more detailed work-plan.
There are several reasons for the need for gelatin from alternative sources especially in Europe as the largest companies in commercial gelatin production are found there. The world wide supply of gelatin is between 200-250 thousand tons per year and the global demand for gelatins has been estimated to increase 3% per annum. However, the consumption of meat is decreasing in Europe as well as there is an increased demand for pig skins for other uses which has resulted in decreased availability of raw material for gelatin production. But there are also opportunities to compensate for the loss as there are a great volumes of under-utilised by-products or waste material specially in the fish industry, i.e. fish skins and bones that could be used to produce gelatin instead of going to waste or low prised by-products.
Description of work
The project is divided into three tasks. In Task 1, the variation in the structure and function of gelatins from different origins are studied with fundamental and empirical methods. Main emphasis is on the study of functional properties of the new gelatins (e.g. fish gelatins) and to relate them to their structural properties studied and finally to compare the results to commercial gelatins. The relationship between structural properties and functional properties is necessary to take into account in order to explain the performance of different gelatins. Also if predictions are to be made of the performance of gelatins in various applications. This type of work has only been done to a small extent on gelatin for historical reasons as gelatin production started without considering such relations of properties. The new gelatins can be looked upon as new biopolymers that need to be characterised thoroughly and for example 50 man years have been used for similar work on gellan gum the past years as that was thought necessary to characterise the new biopolymer to be able to put it on the market. One can argue that the same arguments count for the new gelatins.
In Task 2, gelatin blends of the new and commercial gelatins will be prepared and evaluated. Functional performance of the blends are of special interest and their possible application as well as potential exploitation. In the third Task, modelling of structural and functional properties will be performed based on the results from the project in order to explain our findings and to be able to predict performances of gelatins in various applications.
Measurements on structural properties are performed on gelatin in solution to study coil-helix transitions and gelation i.e. sol-gel transition, both rate and quantity with methods such as optical rotation measurements, atomic force microscopy, interfacial studies with drop volume technique and intrinsic viscosity measurements. Other measurements related to structure are performed like amino acid analysis, molecular weight and weight distribution, isoelectric points and more. Functional properties measured will mainly be theological i.e. viscosity and viscoelastic properties but also foaming ability, film forming and wetting. Performance of blends of novel gelatins and commercial gelatins will be measured and evaluated and their potential application explored. Finally both structural and statistical models will be constructed in order to explain the behaviour of different gelatins and to predict their performances in various applications and blends.
Funding SchemeCSC - Cost-sharing contracts
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