When we see a pig, we all tend to think that every part of it can be used: its delicious hams, pork cracklings, chorizo, loins…..including, as the saying goes “even its walk”. However, at CARTIF we know there ir more beyond that: a great variety of by-products and waste generated during the stages prior to the production of all these products.
A similar situation occurs in the sheep sector. Is not only about milk, used for cheese, or meat, such as suckling lamb, but many types of waste also appear throughout the processing stages, such as skins, viscera, or blood, whose treatment entails, apart from its environmental impact, an additional cost for companies.
The cattle sector, in turn, shares common challenges with the previous ones, facing the management of a long list of waste products such as manure, slurry, blood, bones, viscera, and skins, among others.
In the current context where sustainability and circular economy principles are gaining increasing relevance in industrial processes, waste recovery in the meat industry emerges as a key strategy to optimize resources and reduce environmental impact. The activities of the sheep, pig and cattle sectors (which together account for up to 75% of national meat production) offer enormous potential for the full utilization of their waste. In short, we can talk not only about excellent products (milk, cheese, chorizos or hams), but also about good practices by meat companies, closing the production cycle by generating added value through waste recovery. In most cases, these type of waste are managed by external handlers, representing an additional cost for producers. For this reason, all by-products generated in the meat industry require efficient management and call for innovative ideas to turn them into valuable products.
Source:
An analysis of the meat production process, according to Nedgia, estimates that a cow produces 50kg of manure per day, which amounts approximately 18,250kg/year (1). When the cow arrives at the slaughterhouse, approximately 40 to 50% of its weight consists of by-products, such as bones, blood, hide, víscera, inedible fat and rumen content, all of which must be properly managed.In addition to this, processing a cow at the slaughterhouse may require between 500 and 1,000 liters of water (2), which subsequently becomes a wastewater stream that also needs to be treated.
Approximately 40 to 50% of a cow weight consists of by-products
On the other hand, animal hides are already valorized in the textile and footwear industries, but currently, their demand has decreased compared to other fabrics and synthetic leathers. Therefore, efforts are being made to find alternative applications for their utilization. From hides, as well as from bones and cartilage, collagen can be extracted- a product highly sought after by the cosmetics industry due to its many health benefits. Collagen helps create a protective barrier on our skin against external agents, provides firmness and resilience, promotes wound healing, delays the effects of aging and reduce wrinkles, among other benefits (3). Moreover, its use is associated with improvements in the treatment of common diseases such as osteoporosis, arthritis and osteoarhtritis.
According to the Spanish Academy of Nutrition and Dietetics (AEND), from the age of 25, collagen production in a healthy person begins to decline, and it is estimated that by the age of 40, the body produces only half as much collagen as it did during adolescence, with this decrease becoming more pronounced in women after menopause (4). Moreover, one of the reasons why our bones weaken is due to the lack of collagen in the body (5). Many of us remember seeing our grandmothers boiling cow bones to extract collagen, straining the broth for consumption; when refrigerated, this broth would turn into a gelatin rich in collagen. Today, it is possible to replicate this process in the laboratory to obtain concentrated collagen as a nutritional supplement, which requires a purification process that presents various challenges related to obtaining pure collagen, free of fats and other proteins.
Illustration of young skin layers and components
Illustration showing layers and components of aged skin
Regarding blood, this fraction represents approximately 3–7% of the live weight of the animal, depending on the species, and has traditionally been used in the production of food products (such as blood sausages and others). However, it is also possible to use it for obtaining food colorants or for the extraction of hemoglobin and/or protein that can be incorporated into various products for human or animal consumption. Once the blood has been collected and treated, plasma can be separated from hemoglobin, or the entire fraction can be dried to obtain a protein-rich product.
Another meat by-product is the intestines of animals, which are currently used in the production of sausages such as salchichón, blood sausage, chorizo, and regular sausages, among others. However, the utilization of this fraction (and its associated economic value) remains quite limited. For many years, it has been known that intestines are a rich source of heparin, a highly demanded medication worldwide due to its clinical use as an anticoagulant. The process of obtaining highly pure and stable heparin requires a lengthy preparation and laboratory treatment. Numerous challenges must be overcome during its extraction, such as selecting the most appropriate extraction and purification methods. In addition to using resins, there are other methods that allow heparin to be isolated from other compounds (proteins and other contaminants). Furthermore, it is essential to ensure the stability of the active ingredient, which involves evaluating whether it should be kept in solution or subjected to a drying process.
The valorization of waste from the meat industry is surrounded by many uncertainties, but in this sea of questions, CARTIF emerges, with its researchers studying and developing new processes for the treatment of these by-products, generating new knowledge and finding viable and sustainable technological solutions to these challenges, thereby offering added value to the meat industry.
CARTIF is firmly committed to this line of research, supporting companies in the meat sector in valorizing all their waste, including slurry, for transformation into various products — whether food, energy (such as renewable gases), or even agronomic products (such as organic fertilizers).
As we have seen, it is not only the pig from which everything can be used — even, as the saying goes, “its very walk.”
Co-author.
Pedro Acebes. Researcher at Agrifood and Processes Division
Informe trimestral de indicadores económicos marzo 2025. Sector vacuno de carne. Ministerio de Agricultura, pesca y alimentación. Gobierno de España.
Área de precios. Informe semanal de coyuntura. Precios Coyunturales. Semana 5-2025 del 27 de enero al 2 de febrero. Subsecretaría Subdirección general de análisis, coordinación y estadística.
Plan territorial de Ordenación de residuos de Tenerife. Residuos de mataderos, decomisos, subproductos cárnicos y animales muestras.
Universidad Nacional del Nordeste Comunicaciones Científicas y Tecnológicas 2003. Cedrés, José F.
Foods like quinoa (or quinua) and amaranth are consumed for centuries in the Andes regions. An example of this is that in tombs more than 4,000 years old remains of these products are found which consumption is demonstrated by cultures like the Mayans, Aztecs and Incas, thereby leaving an important food legacy linked to the consumption thereof. In countries such as Bolivia, Colombia, Argentina, Mexico and Peru consumption is very common and rooted in the basic diet.
Did you know that one of its main nutrients are proteins?
Proteins are molecules formed by amino acids that are necessary for the growth of the organism and perform bio regulator functions (form enzymes), the body’s defense (antibodies are proteins), homeostatic (collaborate to regulate the body’s pH), among others.
As you can see is very important protein intake to help the proper functioning of the body.
And where you can find it?
Dietary sources include proteins are meat, eggs, legumes, nuts, vegetables and dairy products.
Did you know that our body is unable to synthesize all the amino acids necessary for its correct functioning?
These amino acids are called “essential amino acids” and are ten; valine, leucine, isoleucine, phenylalanine, tryptophan, methionine, threonine, histidine (essential for infants), lysine, arginine (semi essential). For a protein is considered complete should contain all the essential amino acids, which is why the food we eat should contain, but most foods contain some of these, being necessary for it to use mixes of food, which in its set covering the daily intake of these amino acids. Foods that can mention which are complete proteins are meat, fish, soy, spirulina, quinoa and amaranth among others.
Consumption of quinoa and amaranth began in Europe relatively few years ago, attracted by the existing biodiversity in other regions to provide products with high nutritional value. France has a high consumption of quinoa while in Spain has not yet become widespread. One of the groups that increased consumption of these products have, are celiacs because they do not contain gluten and therefore is used as substitutes for the wheat. In Europe and the United States is consumed as whole grains, flakes, general flour, wholemeal toasted amaranth, amaranth popped the popcorn style, pre-gel powders amaranth, oils Amaranth, cereal bars, breads amaranth, tortillas amaranth and corn, among others.
Quinoa is recognized by the World Health Organization as a great source of nutrients and in 2013 was declared the International Year of Quinoa. NASA procures its crew with quinoa for extended space missions, because it is a very nutritious food. Quinoa is not only used for human consumption but serves as fodder for animal feed because of its nutritional value.
Here are some products that have been developed in other countries on the basis of Quinoa and amaranth.
Already exists wide variety of products containing quinoa and amaranth, and we believe this can be expanded much more if we trust in the capabilities of research centers such as CARTIF that are in continuous search for alternative methodologies to help alleviate various problems, they search for new applications for traditional products or obtaining products with high added value of raw materials and agricultural food waste.
Diets are a fashion and they are always changing. Almost without respite, we passed the liquids’ diet, the lingual mesh and many more. And now, it is the gluten’s turn.
It seems that the main guilty of all kind of fat problems is the gluten. But, is it true? For centuries, we have consumed bread, pasta and pastries. However, the ‘devastating’ gluten effects are more recent. We know some people who suffered stomachaches, headaches or other symptoms when they ate bread or derived products. When they asked their doctors, they said them that they were celiac or gluten intolerant, so they must consume a gluten-free diet. We have started to realize that our friends are losing weight with this kind of diet, and we have had the idea to prove it. But, is it so simple? Could you say goodbye to fatness without the gluten? I suspect not.
From the Spanish Celiacs Associations Federation recommend not start a gluten-free diet without having a bowel biopsy showing intolerance to gluten. Celiacs have to stop eating gluten because if they do it, lymphocytes attack the tissue of the intestine, causing the disappearance of the hair of it and having consequently poor absorption of nutrients.
Nutrition experts are cautious and they advise us against eating without gluten, because of the negative effects it could have on our health. Make a gluten-free diet, without professional assistance, can lead to an unbalanced and inadequate diet with more disadvantages than advantages.
Do you know that oats and barley (food with gluten) are high in soluble fiber?
Soluble fiber is formed by compounds which capture much water and are capable of forming viscous gels, help the growth of bacterial flora and decrease and slow the absorption of sugars and fats in food. This contributes to lower cholesterol and glucose blood. Therefore, it is necessary to consume foods such as oats and barley, which also have gluten. Here we only mention fiber, but foods rich in gluten also provide other essential nutrients for humans like proteins, vitamins and essential minerals.
For all these reasons, it is advisable to stay away from the pastries and the precooked and make a healthier lifestyle with a balanced diet. We must try to replace these products with other homemade foods and fewer calories and, as my mother said, eat a bit of everything but without excesses. In addition, it is important to relying on innovation to solve the problems of people with intolerances or special needs.
In CARTIF, we work on several projects in order to replace the use of industrial additives for other natural and animal fats for healthy compounds. These technological contributions work and help us to eat better. You may not have a perfect figure but, undoubtedly, you will be healthier.
Celiac disease is a condition developed by people who are intolerant to gluten and is characterized by an inflammatory reaction, where the immune system mistakenly attacks the intestine as if it were an external aggressor and causes lesions in the mucous affecting nutrients and vitamin absorption. This disease can affect both sexes by equally and can start at any time, from infancy (as soon as cereal grains are introduced into the diet) to adulthood (even when individuals have consumed cereal grains all his life).
The most common symptoms are weight loss, fatigue, nausea, vomiting, diarrhea, stunted growth, anemia, abdominal pain, among others. Although sometimes is more complicated because there are people who do not show any of these symptoms or they may be so atypical that the diagnosis is difficult. This condition is detected by clinical examination, an analytical measuring specific antibodies (transglutaminase and immunoglobulin A) generated in the intestine and an intestinal biopsy that allows a reliable diagnosis.
But what exactly is gluten? The cause of this disease is a set of proteins contained in cereals such as wheat, barley, rye and oats, and products derived from them (white flour, white wheat, graham flour, Triticum, wheat, kamut, spelled, germ wheat, wheat bran, etc.). According to Molina-Rosell, gluten serves to give elasticity to the masses, allowing the products have volume and an elastic and fluffy. So far, the part that almost all know. But what not everyone knows is that it is also used as an additive to give viscosity, thickness or volume to a lot of foods such as sausage (chopped, mortadella, sausage, black pudding, etc.), pates, cheeses, preserved by meat and fish, sauces, coffee substitutes, chocolat and cocoa, roasted or fried nuts with flour and salt, candy, snacks and some ice cream. In resume, a celiac has it really hard to have a varied diet safely.
Fortunately, there are some solutions for not including gluten in many foods. In the case of cereals, they are replaced wheat, barley, rye and oats with corn, rice, millet, quinoa, etc. With this, celiac could safely consume bread, flour, pasta and biscuits. The problem comes when we realize that the price of these products gluten free can be up to 448% higher than foods with gluten! A very simple example, according to 2015 Prices Report: normal bread costs € 2.11 / kg. Gluten-free bread € 9.48 / kg.
The next question is why? The answer is that the process of preparing food without gluten is considerably more complicated. Without the natural “glue” that gluten produces, the masses are liquid and cannot be baked. For this reason is necessary to use other products that help to simulate the characteristics provided by the gluten. Then the hydrocolloids (locust bean gum, guar gum, xanthan gum, agar, pectins and β-glucans), emulsifiers, enzymes or proteins, starch, combined with fats and dairy derivatives are chosen to impart viscoelastic properties.
But, besides in the process of developing gluten free food, should be used exclusively equipment and utensils, or have been properly cleaned previously. Cannot use oils or fryers where previously fried foods that have gluten, nor can use trays that previously contained gluten products. According to the Guide to prepare menus without gluten, throughout the production process should prevent cross-contamination with gluten products because, for a food to be considered gluten free, must comply with the legislation (Regulation 41/2009) and contain less than 20 mg of gluten per kilogram of product.
Quite a challenge for food R&D, which is already working on new processes and systems that can streamline production and achieve a significant decline in the price of gluten free food.
