Older people have specific protein needs to retain their muscle mass
Meals help maintain a constant muscle mass.
Age-related muscle loss, or sarcopenia, develops very gradually over several years or even decades, and affects all people from the age of 70-75 years. This is a physiological phenomenon but it is accelerated when the dietary protein intake is no longer sufficient to meet the body’s amino acid requirements. Meals can regulate the balance between the synthesis and degradation of muscle protein, and thus maintain a constant muscle mass. With advancing age, meals become less efficient in reconstituting muscle protein reserves.
As for the mechanisms in play in elderly people, the intestine and liver remove a larger share of dietary amino acids to assure their own functioning, the result being that they are less available to renew the protein reserves in tissues such as muscle. Furthermore, the muscle itself is less sensitive to the anabolic stimulants contained in a meal, and particularly insulin and amino acids.
A satisfactory protein intake is therefore particularly important in the elderly, in terms of both quantity and quality. To ensure maximum efficacy, the amino acid content needs to be adapted and proteins should be rapidly assimilable, such as certain dairy proteins (whey proteins).
The scientists involved in the VEGAGE scientific revitalisation project sought to optimise the nutritional value of an inexpensive and easily prepared standard food product, pasta, and adapt it to the needs of elderly individuals.
Plant proteins are often less digestible that animal proteins. Through a careful choice of protein sources, their respective quantities and appropriate transformation processes, the challenge of this project was therefore to make these proteins more assimilable and with a qualitative amino acid profile (essential amino acids) that could meet the needs of this target population of older people.
The challenge of the project is to make these proteins easily assimilable.
A patent1 was filed concerning the manufacture of legume pasta in which the substitution of durum wheat by legume flour (from, amongst others, lentils, pea, Black Gram, field bean) ranged from a minimum of 35% to 100%. This invention enables modulation of the proportions of legume and wheat flour so as to ensure an appropriate intake of essential amino acids, whichever legume is used. The process retains the standard steps for the manufacture of pasta (hydration, mixing, extrusion, drying) so it does not require any additional equipment. The drying temperatures have been lowered in order to achieve a structuring of proteins that will facilitate rapid digestion.
The most interesting pasta contain 60%-80% legume flour, corresponding to a finished product with a 20% protein content (versus 13% for standard pasta) and a good complementarity of essential amino acids: lysine, threonine and sulphur amino acids, unlike durum wheat pasta that is deficient in lysine.
This project has enabled a clearer understanding of how the composition of a mixed plant product (combination of cereals and legumes) can impact the structure of the protein network and the digestibility of proteins. The expertise thus acquired offers glimpses of new opportunities for the development of new plant products with optimised nutritional value.
1 patent FR3030193 published on 24 June 2016 : procédé de fabrication de pâte destinée à l’alimentation humaine et/ou animale comprenant au moins 35% de légumineuse (manufacturing process for pasta for human and/or animal consumption including at least 35% legume flour).
The PASTALEG project, funded by the French National Research Agency (ANR) laid the foundations for knowledge that could link the process, structure and nutritional properties of legume pasta. To progress further in the design of products adapted to the diet of elderly people, it was necessary to utilise skills in human nutrition so as to better understand the impact of changes to protein structure on the nutritional qualities of the finished product. The Qualiment Carnot Institute provided its own funding for the VEGAGE project (2014-2017).
Indeed, a Carnot Institute can issue calls for internal projects, limited to its own research groups. The projects selected are referred to as "revitalisation projects", as in all cases they comply with an increase in the TRL* of the technologies developed.
*Technology readiness level
The institut Carnot QUALIMENT®
The purpose of the Qualiment® Carnot Institute is to facilitate and promote partnership research and to offer industry access to scientific excellence. Each year, it funds several upstream "revitalisation" projects that are designed to generate results that can be transferred to companies.
Qualiment® can offer private sector actors – SME or major industrial groups – a range of cross-disciplinary skills in the field of food: nutritional and sensory qualities, and the processing and structure of foods.
THE QUALIMENT NETWORK: