This is a summary report of Solanic's 1st International Vegetable versus Animal Protein Debate held at the Grand Hotel Krasnapolsky in Amsterdam, the Netherlands on 11 May 2007.
Solanic is the new Avebe subsidiary that uses breakthrough technology to extract high-performance proteins from potatoes.
AVEBE is a leading supplier of potato starch.
Animal or vegetable origin does not determine the value of proteins. Regardless of their origin, there are only high quality and low quality proteins for the human diet, scientists conclude. Potato proteins are generally ranked among the high quality proteins. Apart from dietary value, functionality and stability during food processing are also important. Proteins isolated with newly developed mild separation technology of AVEBE/Solanic perform remarkably well, the company claims. The product launch of Solanic’s potato proteins is announced for the autumn of this year.
“The mild separation technology of AVEBE/Solanic is an example of how rewarding science can be”, prof.dr.ir. Rudy Rabbinge of Wageningen University, the Netherlands, states. “Today’s starch production results in high energy and water consumption and a lot of waste material. A new separation process not only reduces energy and water consumption dramatically, it also changes a waste product into a promising vegetable protein.
At Solanic, potato juice passes pre-treatment and adsorption steps. After this the production flow divides into two separate product flows. There is a high molecular fraction, containing mainly the protein Patatin. This results in a dry food ingredient. The low molecular fraction ends up as a liquid product that mainly contains a protein fraction comprising the Protease Inhibitors present in potato. Question is: what are the potentials and possibilities of these proteins as food ingredients?”
Prof.dr.ir. Gertjan Schaafsma of Schaafsma Advisory Services, the Netherlands comments on that, comparing potato protein with other protein sources: “In the first place, I would like to remark that the present recommendations of minimum human protein intake now should be regarded as too low for at least certain categories of people. Elderly and athletes could benefit from higher protein intake with regard to maintaining their muscle mass. Apart from that, the role of proteins in weight management shouldn’t be underestimated. Proteins stimulate satiation and satiety. And we know that high quality proteins contribute to the proper functioning of the intestine, where seventy percent of the immune system is determined.”
Protein quality
Schaafsma subsequently addresses protein quality. What is the amino acid content of the protein? What is the digestibility of amino acids in the protein? Are there any anti-nutritional factors involved? How does the protein contribute to the ‘fortification’ of amino acid patterns of inferior proteins, for instance in wheat? “On such quality issues, potato protein scores even better than soy protein, which is regarded as one of the best vegetable proteins. In fact, the origin of protein, be it vegetable or animal, is not even what matters. What counts is the quality of the protein, period.”
Prof.dr. Daniel Tomé of AgroParisTech/INRA, France, points at the fact that more scientific knowledge is available on animal protein. “Some aspects of the proteins remain to be determined, like the extend of low allergy properties. But in general, we know that cereals are limiting in the indispensable amino acid Lysine and legumes are limiting in Methionine and Cysteine, whereas animal proteins have no limiting in amino acids. But we also know, that the differences between the various vegetable protein sources are quite large. Some don’t live up to animal protein quality standards and others do. In my view, amino acids in proteins are not the most important issue anymore, as the diet in the West covers the necessary intake. When it comes to the quality of proteins, their specific role in energy homeostasis and health related consequences is an important issue for further investigation.”
Dedicated production
It is on this specific role of potato protein that prof.dr.ir. Harry Gruppen of Wageningen University, the Netherlands, focuses. For a long time, the potato was not a likely source of protein, he explains. The protein content in potatoes is only one to two per cent. “Potato juice, as a waste product of starch production, has the same low protein content. For a long time, this protein content was regarded as not commercially interesting. But it is the protein content in dry matter of at least 27%, that changes matters.”
A further interesting fact isthat, in contrast to traditional isolation methods for potato protein, the new mild separation technology enables to isolate soluble proteins from potatoes, whereas proteins from cereals and legumes are normally insoluble. This gives potato proteins benefits over other plant proteins. “And, as opposed to soy, this solubility of extracted protein covers the whole pH-range, including pH-values of food applications. Furthermore, purified potato protein has good foaming and emulsifying properties. Next to this, they exhibit bio-functional properties”, Gruppen states.
As to these last properties, potato protein holds the promise of ‘selective inactivation’. Gruppen: “The protein fraction in potatoes is present as 30-40% Patatin and 50-55% Protease Inhibitors. Applications focusing on Protease Inhibitors - blocking certain enzymes – are possible. On the other hand, when Protease inhibition is an unwanted feature, it is quite easy to get rid of half of the Protease Inhibitors by heating the product up to 60°C. The temperature range allows this without seriously damaging the solubility. In other words: potato protein in principle enables dedicated production for dedicated applications.”
Stability
Where Gruppen looks at the protein and reasons from there towards applications, dr. Aard de Jong of TNO Quality of Life, the Netherlands, works the other way round. He focuses on the desired functionalities of proteins in food and food processing, like water binding capacity, viscosity, gelation, foam formation and emulsification. And is the protein stable to for instance heat and acid in real food production processes with their complex interaction patterns? De Jong: “Cost is always an issue. Apart from that, the market potential of potato proteins will be defined by solubility – which appears to be good - , stability and functionality. Also, the possibility to use potato proteins as a whole or fractionate is of importance.”
Before addressing these issues, dr.ir. Marco Giuseppin, CTO of Solanic, the Netherlands, reflects on the remarks of professor Rabbinge on sustainability. “The new mild separation technology for the isolation of potato proteins replaces heat coagulation, invented in the 1970-ies. Mild processing leads to a 30% reduction in energy consumption. Water consumption drops considerably. Furthermore, the protein yield per hectare of potatoes is one of the best, with 500 to 1,000 kg as compared to 12 kg for veal.” Obviously, turning a low value fraction - until now only used for production of animal feed - into a high value food ingredient is also a favourable aspect for sustainability.
Having said this, Giuseppin elaborates on what De Jong mentions as a major issue: stability. “Potato protein isolated by heat coagulation is highly unstable and insoluble. The role of the separation process is accentuated by the fact that clean separation in a few steps results in stable proteins.”
Market launch
Giuseppin sums up other favourable characteristics: “Extremely high solubility, excellent gelling and foaming capacity if wanted. Our potato protein equals or surpasses all other animal or vegetable protein sources in functionality.
As for nutritional properties, it scores very high too, with for instance low allergenicity as interesting feature.”
An important issue regarding the production process is that the Solanic approach results in two major fractions. Giuseppin: “Each has its own specific field of application. Our process is the result of several years of hard work. We now have a robust process for large scale protein production aimed at high added value food applications. Product development with customers in the dairy, bakery and meat areas is in full swing, but still confidential. Shortly, the market will get the opportunity to meet the results.” The first commercial applications are expected in the autumn of this year at the Fi Europe in London.
Protein debate
“Launching customers are enthusiastic about Solanic’s potato protein, we hope the academic world will react likewise”, CEO Okke Koo of AVEBE explains in his opening words of the First International Vegetable versus Animal Protein Debate.
Click here to read FLEXNEWS' interview with Solanic’s representative director, Frank Goovaerts: "Avebe's Solanic Innovates with Unique Food Ingredients, Potato Proteins".