Lupin flour (Lupinus spp.)

Lupin flour is mainly derived from Lupinus albus, L. angustifolius and L. luteus. It is available as “whole” flour (from hulled and ground seeds), partially defatted (from mechanical pressing) or as a high-protein ingredient (concentrates/isolates). It is naturally gluten-free and is suitable for use in bakery products, snacks and plant-based “alternatives”.

Lupin ( Lupinus albus L.) is a plant belonging to the Fabaceae family which grows in the Mediterranean regions. The genus Lupinus includes about 200 species, but the most known species are

• Lupinus albus L.
• Lupinus angustifolius L.

Lupin (Lupine) (Lupinus spp.)
The Term “lupin” covers several cultivated species for food, chiefly Lupinus albus (white lupin), L. angustifolius (blue/australian lupin), and L. luteus (yellow lupin). Commercial forms include dry seeds for soaking and cooking, brined ready-to-eat seeds, flours and protein concentrates, flakes or grits for bakery and snacks, and functional ingredients for plant-based products.

Caloric value (seeds, dry)
About 350–400 kcal per 100 g (typical ≈ 371 kcal/100 g; varies with species, moisture, dehulling, and debittering).

Average composition (dry seeds, per 100 g)
Protein: ~36–40 g with a favorable essential amino acid profile, sometimes limiting in methionine and cysteine.
Fat: ~6–12 g, predominantly MUFA and PUFA.
Available carbohydrates: generally ≤10 g, very low starch with non-starch polysaccharides prevailing.
Total fiber: ~25–35 g with high water-holding capacity.
Minerals: K, Mg, P, Fe, Zn, Mn; Se may vary by soil and species.
Vitamins: B-group (thiamine, riboflavin, niacin, folates) depending on variety and processing.
Phytochemicals and antinutrients: quinolizidine alkaloids (for example lupanine), phytates, protease inhibitors, and raffinose–stachyose family oligosaccharides.

Fatty acid profile (lupin oil, % of total fat)
MUFA (generally favorable): oleic ~40–55%.
PUFA (beneficial yet to be balanced): linoleic ~25–40%, with smaller ALA.
SFA (to moderate): palmitic + stearic ~8–12%.
The Presence of tocopherols and phytosterols, together with moderate PUFA, supports fair oxidative stability versus many other legumes.

Sensory and technological properties
Flavor Is mild with legume and occasional grassy notes; persistent bitterness indicates insufficient alkaloid reduction.
Lupin Proteins exhibit useful emulsifying, foaming, and water/fat-binding properties for sauces, spreads, and bakery.
Flour Can improve water retention and softness in bakery, though high inclusion may weaken gluten networks in wheat doughs.
Light Roasting or controlled lactic fermentations can reduce oligosaccharides and “beany” notes, improving digestibility and acceptance.

Debittering, alkaloid safety, and process aspects
Quinolizidine Alkaloids drive bitterness and, at high levels, adverse effects; food supply chains favor “sweet” low-alkaloid varieties plus soaking, repeated washings, and cooking to reduce them to safe levels.
Brined Snack Lupins often carry higher sodium due to the brine and call for moderation in sensitive individuals.
Effective Debittering depends on pH, time, temperature, and water exchange, while limiting nutrient losses.

Food applications
Lupin Flour And intermediates serve as protein- and fiber-rich ingredients in breads, bakery, enriched dry pasta, bars, and extruded snacks.
Protein Concentrates/isolates support emulsions and aerated structures, enabling partial substitution of eggs or dairy in vegan formulations.
Cooked Or Brined Seeds are consumed as snacks or added to salads and cold dishes; their firm texture suits ready-to-eat uses.
Plant-Based Applications leverage protein functionality for burgers, patties, and dairy/meat analogues.

Nutrition and health
Lupin Is naturally gluten-free and pairs high protein density with abundant fiber, aiding satiety and glycemic management.
MUFA/PUFA Provide a favorable lipid profile within balanced diets, with modest SFA.
Oligosaccharides May cause bloating in sensitive individuals; soaking, cooking, and fermentation reduce their impact.
Cross-Reactivity Can occur in people allergic to peanut or other legumes; cautious introduction is advisable in at-risk profiles.
Typical Serving: ~30–50 g drained brined seeds as a snack, or ~10–30 g of flour in home recipes.

Allergens and safety
Lupin Is a regulated allergen in the European Union and several other jurisdictions, with documented IgE-mediated reactions potentially severe.
Risk Management includes varietal selection, validated debittering, prevention of cross-contact in facilities processing other legumes, and clear labeling of intentional or incidental presence.
Gluten-Free Status does not remove other allergy risks; products should carry required advisories.

Quality and specifications (typical topics)
Dry Seeds: controlled moisture, absence of bitter/defective seeds, compliant microbiology, alkaloids within internal safety targets.
Flours And Proteins: moisture typically ≤10%, defined protein yield and solubility index, controlled protease inhibitor activity, clean color/aroma without oxidative notes.
Oil And Lipids: low peroxide and anisidine indices, compliant FA profile, tocopherols and phytosterols as quality markers.
Residues And Contaminants: pesticides and heavy metals within legal limits; mycotoxins mitigated via proper drying and storage.

Storage and shelf life
Dry Seeds: cool, dry, dark, airtight to limit oxidation and infestation; barrier packaging extends life.
Flours And Concentrates: low humidity, protective atmosphere, moderate temperatures; lipids, though modest, can oxidize over time.
Brined Seeds: keep covered by brine; refrigerate after opening and consume within the indicated period.

Troubleshooting
Persistent Bitterness: indicates insufficient debittering; repeat soaking and water exchange or blend with certified sweet batches.
Dense Or Crumbly Doughs: suggest excessive lupin flour or inadequate hydration; increase water, add a natural emulsifier, or reduce inclusion.
Pronounced Beany Notes: mitigate via light roasting, controlled fermentation, and label-coherent natural flavoring.
Emulsion Break: improve soluble protein fraction, optimize pH and ionic strength, or apply mild heat treatment.

Sustainability and supply chain
Lupin Is an N-fixing legume that improves soil fertility and reduces nitrogen fertilizer needs, supporting positive crop rotations.
Traceable Chains—especially low-alkaloid varieties—deliver consistent quality and lower waste; organic options are available in many growing regions.
Industrial Demand Is growing in Europe and Oceania due to high protein yield and technological versatility.

Conclusion
Lupin Combines high-quality protein, abundant fiber, and valuable techno-functionality, offering concrete opportunities in bakery, snacks, and plant-based categories. Rigorous alkaloid management, allergen prevention, and tight process control allow producers to realize its nutritional and sensory potential while upholding safety and quality.

Mini-glossary of lipid acronyms (English)
MUFA — MonoUnsaturated Fatty Acids: Generally favorable for cardiometabolic profile (e.g., oleic acid).
PUFA — PolyUnsaturated Fatty Acids: Include omega-3 and omega-6; beneficial, but keep a balanced omega-6:omega-3 ratio.
SFA — Saturated Fatty Acids: To moderate; impact depends on overall diet and the replacement nutrient.
ALA/EPA/DHA (omega-3) — Alpha-linolenic acid / Eicosapentaenoic acid / Docosahexaenoic acid: Support heart and brain health, with stronger evidence for EPA/DHA.
TFA — Trans Fatty Acids: To avoid; associated with increased cardiovascular risk.
MCT — Medium-Chain Triglycerides: Rapidly absorbed; useful in specific contexts, but still count toward total calories.

Studies

Its seeds have high protein content, are used in food, cosmetics and pharmaceuticals, contain 36-52% protein, 30-40% fiber and 5-20% essential oils, as well as oleic and linoleic acids, isoflavonoids, zeaxanthin, thiamin, riboflavin and niacin (1),

Data from this study demonstrate that a plant-based vaccine from a genetically engineered plant, the narrow-leafed lupin (Lupinus angustifolius L.), can promote a protective immune response and attenuate experimental asthma, suggesting that plant-based vaccines may be potentially therapeutic for protection against allergic diseases (2).

Lupine seeds are very low in isoflavones, and lupine protein isolates are essentially free of isoflavones and may provide a useful alternative for people wishing to replace animal with plant-based protein for cardiovascular disease prevention. This initial study indicates that lupin, although lacking isoflavones, has cholesterol-lowering activity similar to that of other leguminous proteins in an established animal model. Furthermore, cholesterol reduction appears to be associated with stimulation of LDL receptors by a well-defined protein component of lupin seeds, as demonstrated by in vitro studies (3).

In a study on the effect of lupin protein on circulating cholesterol in plasma and lipoproteins of hypercholesterolemic subjects, a slight lowering of LDL cholesterol concentration was found in hypercholesterolemic subjects, without alteration of HDL cholesterol. No effects or minor effects of lupin protein on circulating glucose, homocysteine, and plasma amino acids were observed (4).

Lupine studies

References___________________________________________________________________

(1) Andor B, Danciu C, Alexa E, Zupko I, Hogea E, Cioca A, Coricovac D, Pinzaru I, Pătrașcu JM, Mioc M, Cristina RT, Soica C, Dehelean C. Germinated and Ungerminated Seeds Extract from Two Lupinus Species: Biological Compounds Characterization and In Vitro and In Vivo Evaluations. Evid Based Complement Alternat Med. 2016;2016:7638542. doi: 10.1155/2016/7638542.

Abstract. In recent years, nutraceuticals attracted a great amount of attention in the biomedical research due to their significant contribution as natural agents for prevention of various health issues. Ethanolic extracts from the ungerminated and germinated seeds of Lupinus albus L. and Lupinus angustifolius L. were analyzed for the content in isoflavones (genistein) and cinnamic acid derivatives. Additionally, the extracts were evaluated for antimicrobial, antiproliferative, and anti-inflammatory properties, using in vitro and in vivo tests. Germination proved to be a method of choice in increasing the amount of genistein and cinnamic acid derivatives in both Lupinus albus L. and Lupinus angustifolius L. seeds. Biological evaluation of all vegetal extracts revealed a weak therapeutic potential for both ungerminated and germinated seeds.

(2) Smart V, Foster PS, Rothenberg ME, Higgins TJ, Hogan SP. A plant-based allergy vaccine suppresses experimental asthma via an IFN-gamma and CD4+CD45RBlow T cell-dependent mechanism. J Immunol. 2003 Aug 15;171(4):2116-26. doi: 10.4049/jimmunol.171.4.2116. 

Abstract. Allergic asthma is currently considered a chronic airway inflammatory disorder associated with the presence of activated CD4(+) Th2-type lymphocytes, eosinophils, and mast cells. Interestingly, therapeutic strategies based on immune deviation and suppression have been shown to successfully attenuate the development of the asthma phenotype. In this investigation, we have for the first time used a genetically modified (GM) plant, narrow leaf lupin (Lupinus angustifolius L.), expressing a gene for a potential allergen (sunflower seed albumin) (SSA-lupin) to examine whether a GM plant/food-based vaccine strategy can be used to suppress the development of experimental asthma. We show that oral consumption of SSA-lupin promoted the induction of an Ag-specific IgG2a Ab response. Furthermore, we demonstrate that the plant-based vaccine attenuated the induction of delayed-type hypersensitivity responses and pathological features of experimental asthma (mucus hypersecretion, eosinophilic inflammation, and enhanced bronchial reactivity (airways hyperreactivity). The suppression of experimental asthma by SSA-lupin was associated with the production of CD4(+) T cell-derived IFN-gamma and IL-10. Furthermore, we show that the specific inhibition of experimental asthma was mediated via CD4(+)CD45RB(low) regulatory T cells and IFN-gamma. Thus, our data demonstrate that a GM plant-based vaccine can promote a protective immune response and attenuate experimental asthma, suggesting that plant-based vaccines may be potentially therapeutic for the protection against allergic diseases.

(3) Sirtori CR, Lovati MR, Manzoni C, Castiglioni S, Duranti M, Magni C, Morandi S, D'Agostina A, Arnoldi A. Proteins of white lupin seed, a naturally isoflavone-poor legume, reduce cholesterolemia in rats and increase LDL receptor activity in HepG2 cells. J Nutr. 2004 Jan;134(1):18-23. doi: 10.1093/jn/134.1.18.

Abstract. White lupin (Lupinus albus, L.), a widely cultivated crop that has been consumed for many years in Western Europe, may provide a useful alternative for individuals wishing to substitute animal with plant proteins for cardiovascular disease prevention. Lupin seeds have a very low content of isoflavones, and lupin protein isolates are essentially isoflavone free. In rats fed a casein-based cholesterol + cholic acid diet, a relatively low daily intake (50 mg/d by gavage for 2 wk) of total lupin protein extract reduced plasma total and VLDL + LDL cholesterol concentrations by 21 and 30%, respectively (both P<0.001). In an attempt to elucidate the lipid-lowering mechanism, LDL receptor activity was evaluated in a human hepatoma cell line (HepG2). In this model, the lupin total protein extract was essentially inactive, whereas one purified minor protein component, conglutin gamma, had a remarkable upregulatory effect, with maximal increases of 53 and 21% (both P<0.05) for LDL uptake and degradation, respectively. This initial study indicates that lupin, although isoflavone free, has hypocholesterolemic activity similar to that of other leguminous proteins in an established animal model. Further, the cholesterol reduction appears to be associated with stimulation of LDL receptors by a well-defined protein component of the lupin seeds as demonstrated by in vitro studies.

(4) Weisse K, Brandsch C, Zernsdorf B, Nkengfack Nembongwe GS, Hofmann K, Eder K, Stangl GI. Lupin protein compared to casein lowers the LDL cholesterol:HDL cholesterol-ratio of hypercholesterolemic adults. Eur J Nutr. 2010 Mar;49(2):65-71. doi: 10.1007/s00394-009-0049-3.

Abstract. Background: Lupin protein had hypocholesterolemic effects in laboratory animals. However, the effect in humans has not been elucidated till now. Aim of the study: To investigate the effect of lupin protein on circulating cholesterol in plasma and lipoproteins of hypercholesterolemic subjects. Subjects and methods: A randomised, double-blind, placebo-controlled, parallel trial (23 females and 20 males completed the trial) was conducted to compare the effects of lupin protein versus casein as control protein on plasma lipids and amino acids. Thirty-five grams of the test protein were consumed daily for 6 weeks. Results: Both lupin protein and casein resulted in a reduction of circulating plasma cholesterol (-0.50 +/- 0.64 and -0.47 +/- 0.79 mM; P < 0.05) from baseline to week 6. The reduction of plasma cholesterol was mainly caused by a reduction of LDL cholesterol in the lupin protein group (-0.31 +/- 0.46 mM; P < 0.05), while in the casein group HDL cholesterol significantly declined (-0.17 +/- 0.15 mM; P < 0.05). Comparing the lupin protein group with the casein group yielded a difference in the net changes from baseline to week 6 in the LDL:HDL cholesterol-ratio of -0.24 (95% CI: -0.007, -0.479; P < 0.05). No significant differences in net changes were observed for plasma concentrations of triglycerides, glucose, homocysteine, taurine and most of the amino acids. Conclusions: Lupin protein compared to casein slightly lowered the concentration of LDL cholesterol in hypercholesterolemic subjects, without altering HDL cholesterol. No or minor effects of lupin protein were observed on circulating glucose, homocysteine and plasma amino acids.