Recently I have become fond of a very special legume, and not as a spoon dish but as a simple snack or aperitif. I’m talking about lupins, a really nutritious, healthy legume that doesn’t necessarily have to be eaten in a stew. Let’s talk about its cultivation, nutritional properties and characteristics of this not so well known legume.

WHERE DO LUPINS COME FROM?

When we speak of lupins or also called lupines or lupines, we can be referring to three or rather four species of the genus Lupinus that vary in the color of their flower and therefore are known in a vulgar way as white, blue and yellow lupins being the names scientists L. albus , L. angustifolius and L. luteus respectively. They are of Mediterranean origin, and according to the species from some other place. The white lupine from the Balkans, the yellow from Spain and the blue from the Mediterranean basin without specifying where, although it could be from the Middle East. In fact in English lupine is called Egyptian lupine .

There is another one of Andean origin called Lupinus mutabilis that also has a blue flower. These 4 species have been used as a forage species for livestock for millennia and their seed for human and animal consumption as well. It was a great protein contribution for the cattle.

The species most used for consumption in Europe has been Lupinus albus , the white lupine .

There are other species, many species of the genus Lupinus , all of them legumes. Specifically, 626 species of the genus are currently described out of a total of 1229 according to The Plant List. The rest are synonyms or plants that have not yet been evaluated.

ARE LUPINS “POOR” LEGUMES?

Historically yes. They were considered of low quality. Don Juan Manuel already told us in the fourteenth century in his tales of “El Conde Lucanor.”

About what happened to a man who, out of poverty and want of something else, ate lupins.

In a conversation between Count Lucanor and his adviser Patronio, the latter tells him a story of two men who had been very wealthy. One of them reached a state of poverty such that eating lupins remembered the times of wealth, without stopping eating them even if they were bitter, they tasted bad and he had to get rid of the shells.

When he turned around, he saw another man who was eating the shells that he left behind, and when he asked him why he was eating them, he told him that he had been even richer than him but that now, being so poor, he was full of rejoicing at power. eat the shells he threw away. This comforted the first man, seeing that there was someone even worse than him. He reflected and strove to regain his wealth that he would later achieve. The “moral” of this little story:  Never faint because of poverty, because you will see others poorer than you. Here you can read the original story.

And the fact that a literary work from the Middle Ages such as “El Conde Lucanor” refers to lupins as food for the poor, bitter, with a bad taste and with a hard shell, puts this legume in a very bad place.

WHAT GOOD ARE LUPINS IF THEY ARE SO BAD?

Coming back to the present, it has never been considered a good quality legume. It is a bit rough, with tough meat and even tougher skin, with a bitter taste (we will see this later). In addition, in monogastric mammals they cause flatulence (although we already know this from other legumes). The social disadvantage must also be mentioned, right? Be that as it may, it has never been very prominent.

1. It has been used and continues to be used as a forage legume for livestock feed, although it was not highly recommended due to a small alkaloid problem.
2. As an ornamental plant Have you ever seen the lupine flower? They are very attractive flowers, which are grouped in apical clusters of yellow, blue … according to the species, as we have seen.
3. Like green manures . There are historical references to its use as green manure in the Mediterranean centuries before the 19th century. And there is evidence of its cultivation for 2400 years. Being a nitrifying plant, it is perfectly suitable to be cultivated as a natural fertilizer since it meets the necessary requirements to be an exceptional green manure:

• • Grows well in poor soils
  • It does not compete with the main crop. This is crucial.
  • Consume little water.
  • Its vegetative part is prominent. It generates a good amount of green mass (it is what is interesting as green manure).
  • It is of annual growth and relatively fast as herbaceous.
  • It has a root system that expands and deepens with some ease.

And this is where the importance of legumes as green manure is wielded. Why are they so good? In short: They fix nitrogen , so necessary for plant nutrition .

In addition, they achieve a mobilization of phosphorus in the soil, improve its structure thanks to its root system and it is very good for crop rotations in the sanitation of weeds and diseases in cereal areas.

So they can’t be eaten? Are they not worth as food? Let’s go step by step.

LEGUMES ARE HEALTHY. FOR US AND FOR THE GROUND.

Legumes have been said many times to be healthy. Chickpeas, beans, beans, lentils, peas, broad beans … All these plants are legumes. Pod plants that give us really healthy nutritional properties. Its protein content of high nutritional value , make this family of plants a base that every food pyramid should have.

In fact, the Mediterranean diet is often based on the consumption of legumes. Low fat and high protein value. Another thing is that the stew dishes have in addition to the legume, half chopped pork and we raise the cholesterol. But that is no longer a problem for the legume in question. Legumes can be eaten more often without so many meat dressings.

HOW DO LEGUMES BENEFIT THE SOIL?

If you are not involved in the world of agriculture, it may not sound like it, but you should know that legumes are great nitrogen fixers in the soil . They are considered plants that provide nitrogen, just the opposite of the rest of the garden crops. Therefore, in crop rotations , one or two legumes always come into play.

Because they let the soil rest, because in reality, rather than consuming nutrients from the soil, it provides them! Recall that nitrogen is one of the main macroelements of plant nutrition (NPK: nitrogen, phosphorus and potassium) and is the fundamental basis for the growth of almost all plants, but legumes are the exception to the norm. Instead of being nitrogen consumers, the overall balance in their development as a plant is that they contribute more nitrogen to the soil than they consume.

IT’S TIME TO TALK ABOUT THE ALKALOIDS OF LUPINS

There are many questions around lupins. Are lupins fattening? What are lupins good for? They are healthy? What are the benefits of lupins for the body? We are going to answer this with facts and numbers.

One of the main reasons why lupine has not led the legume scene, both for consumption and for forage, is its content in toxic alkaloids that subtract practically all the nutritional value of this plant. The bitter taste of lupins is due precisely to this alkaloid content. Mainly they are lupanin , lupinin and sparteine .

In various media it is said that lupins can cause a disease called lathyrism . This is not true since lathyrism is produced by excessive intake of pea grass or pea flour, another legume that has an amino acid known as ODAP. The problem is that grass pea ( Lathyrus sativus ) and lupine are often confused . In fact, if we look carefully on the internet, lupine is also called almorta in some places and one plant has nothing to do with the other.

THE KEY IS IN THE NEW VARIETIES

From what Don Juan Manuel said in his stories more than 700 years ago to what is currently grown, something has changed. First, varieties and cultivars today allow you to remove much of the bitterness, that is, reducing considerably its content in alkaloids , thanks to the selection of genotypes that produce trace amounts of these compounds.

The total alkaloid content in white lupine varieties has been reduced in the process of domestication and genetic improvement and does not currently exceed 0.02% (Prusinski, 2015).

In any case, all these bitter alkaloids can be removed by various treatments widely applied in the kitchen, such as fermentation , soaking or cooking . In fact, it is very interesting to go to the etymology of common names because they tell us many things:

The common name known as chocho, according to the RAE, comes from the Mozarabic  šóš, and this from the Latin salsus “salty”, precisely because it is prepared in this way to remove the bitterness. The lupins or lupines are soaked in salted water for a few hours to remove the bitterness, that is, to remove the alkaloids present.

PROPERTIES AND BENEFITS OF LUPINS

Once we have clarified the “toxic” part of the lupins, we are going to see their properties. Modern varieties, the so-called sweet lupins , are being evaluated from a nutritional point of view with surprising results and very interesting derived benefits.

All the data below is taken from the following 2017 study ( White Lupine (Lupinus albus L.) – Nutritional and Health Values ​​in Human Nutrition – a Review ), which is nothing more than a meta-study (compilation of various studies) on lupins, for their nutritional properties discovered or rather, rediscovered.

At first we can consider lupins as a very, very healthy food.

NUTRITIONAL CHARACTERISTICS OF LUPINS

• Fat content of around 8%. Being mostly high quality fatty acids (unsaturated) .
• High content of insoluble fiber with the benefits that this entails for the intestinal tract.
• Food considered low calorie. Approximately 100 kcal / 100 g
• They have a low glycemic index , making it a recommended food for people with diabetes. There is even talk of the potential beneficial effects of certain compounds such as β-conglutins for the treatment of diabetes as this study shows . Eye to the word potentials; It is important. It is not a categorical study in its claims. Only subsequent studies and successive scientific advances will be able to demonstrate this reliably. Let’s say they establish a line of investigation in this regard.
• High protein value since it contains high amounts of the 9 essential amino acids that we must incorporate into the diet. Between 33-38% are proteins.
• Its Omega 6 / Omega 3 acid ratio is exceptional. The n-6 / n-3 ratio is 2.11.
• They lack gluten so they are suitable for coeliacs.
• It stands out in minerals such as potassium, manganese and magnesium, iron and calcium and sodium.

In addition, the study mentions: «A diet high in lupine protein has an effect on a significant decrease in blood cholesterol , including LDL (the bad one we all say) and also the level of triglycerides and glucose in addition to decreasing blood pressure (Arnoldi 2005; Nowicka et al. 2006). »

With this social wave of healthy eating, we are recovering food that we had left parked, either because of fashion, or because the food industry has offered us new things … whatever, but lupins are seeing a rebound in demand and therefore in production. We just have to go to FAO data and we will see a truly surprising rebound in the last 10 years of the cultivation of this legume in Europe. Is this rebound due to higher production for livestock feed? It may be, but we want to think that there may also be part of the demand for human consumption.

WHAT CAN BE DONE WITH LUPINS

You can make things like lupine hummus, sautéed lupins, and even eat them as a pickled snack that is already sold in supermarkets and stores. We can even pickle them by doing the soaking and washing operations to remove the bitterness and eliminate the alkaloids. Stews can be made and cooked with them and if lupine flour is obtained, it can be used for cakes, lupine breads etc.

LUPINE CULTIVATION

If we have convinced you of the properties and you want to include lupins in your diet or in your garden as an ornamental, or in your garden as green manure, now we will tell you how they are grown and what their agronomic needs are. And if you are not going to eat them, you can always look for purely ornamental seeds of the genus Lupinus because there are real beauties selected for the sole purpose of decoration. Here is an example.

TEMPERATURE AND LIGHT

It needs direct light or it can be given in semi-shady conditions. In productive crops it is clear that it is in full sun. It supports non-continuous frosts that do not exceed -2ºC . In varieties that are not resistant to cold, we must avoid frost, especially in those crops grown in autumn.

SOIL CHARACTERISTICS

Taking into account that it is used as green manure, we deduce that the lupine does not demand too much from the soil . It grows well in poor soils and does not need additional nitrogen fertilization. It’s only going to have a couple of slightly limiting factors. The pH and texture of the soil.

• The first is the pH since it prefers acidic . Around 6, even neutral (7) although it can support ridiculously low pHs for most plants, below 5. It does not support well limestone , basic soils with a high amount of calcium carbonates.
• The second limiting factor is the structure of the soil. It does not support compact or heavy soils. It must have good drainage and be light in texture to promote deep root development and not rot due to root suffocation. Therefore, sandy or loamy.

The lupine consists of a main root that can easily reach great depths and contains nodules of bacteria of the genus Rhizobium sp . which are those that help the incorporation of atmospheric nitrogen into the soil.

SOIL PREPARATION AND PLANTING

It is advisable to carry out a deep tillage of the lupine to thin the soil before sowing. An elevation and a cultivator pass to loosen the soil. A total turning of the soil profile is not necessary.

It is not a plant that requires protection in the seedbed. In fact the transplant hurts it, and being relatively rustic it is advisable to do direct sowing .

Sowing is done depending on the climate:

• In temperate climates where winters are not very severe, it can be sown in October .
• In harsher winters , it is usually planted at the end of February, when spring begins to dawn. The production and quality of the seed is lower.

Harvesting, therefore, will influence according to the time of sowing. In the autumn plantings of benign climates, in June they will be practically for the harvest. In cold climates, it won’t be possible until after the summer.

The sowing doses vary according to the species, but in white lupine ( Lupinus albus ) it is established at about 120 kg / ha on a medium to broadcast basis. In the other two species it drops considerably to about 50-70 kg / ha.

IRRIGATION

It is tolerant to drought but if it is to be grown for productive purposes, watering is needed especially in the flowering periods . In March April if sown in October. In summer if it is sown in March. Depending on the climate this varies. Although it requires some irrigation at specific times, it is not a plant that needs very high rainfall regimes during the year (250-500 l / m² per year). It can be cultivated in both rainfed and irrigated systems .

SUBSCRIBER IN LUPINE CULTIVATION

Nitrogenous fertilizer is not really necessary for what we have already seen as it is a nitrifying plant. It does not require this contribution or very little. But, like irrigation, if it is grown for productive purposes, it would be necessary to fertilize it taking care of the other 2 macronutrients. Phosphorus and potassium in their P2O5 and K2O forms. We must not forget the contribution of sulfur or even amino acids. There are commercial formulations with amino acid contributions for legumes in formulations of AA (6%) and NPK 2-5-5 for example. But there are many formulations even with 0 nitrogen. They are also valid.

PESTS AND DISEASES OF LUPINS

It does not have excessive problems. In fact, the function of the aforementioned alkaloids is precisely a defense mechanism of the plant against the ingestion of herbivores and certain pests such as aphids, thrips etc. Hence it is so rustic. They can suffer from cryptogamic diseases such as Fusarium or Botrytis but it is not common. Perhaps if it occurs in slightly more humid climates than it should or due to excessive watering. In a normal crop, they shouldn’t appear.

References:

1. Janusz, P. (2017). White lupine (Lupinus albus L.) – nutritional and health values ​​in human nutrition – a review. Czech Journal of Food Sciences ,  35 (2), 95-105.
2. Naruszewicz, M., Nowicka, G., Kosiewicz Latoszek, L., Arnoldi, A., & Sirtori, C. (2007). Lupine protein (Lupinus albus) intake decrease blood pressure and other cardiovascular risk factors in smokers. A pilot study. In  European Nutrition Conference  (Vol. 51, No. Suppl. 1, pp. 273-273). Karger.
3. Lima-Cabello E, Alché V, Foley RC, Andrikopoulos S, Morahan G, Singh KB, Alché JD, Jimenez-Lopez JC *. Νarrow-leafed lupine (Lupinus angustifolius L.) β-conglutin proteins modulate the insulin signaling pathway as potential type 2 diabetes treatment and inflammatory-related disease amelioration. MOLECULAR NUTRITION & FOOD RESEARCH 2016 Dec 24.
4. Azcoytia, C (2012). History of the almorta or the poison that arrived after the Spanish Civil War. Place of publication: https://www.historiacocina.com/es/historia-de-la-almorta