Black Beans

Overview

Black beans provide plant protein, polyphenols, and prebiotic fibre. Soaking and cooking under optimal conditions (about 60°C and pH 6.0) can substantially reduce phytate and improve mineral bioavailability [1]. Black beans are polyphenol-rich legumes that support gut health within diverse plant-forward dietary patterns [2].

Key Nutritional Highlights

• Lysine-rich plant protein (~5.4 g per 100 g) with methionine/cysteine as limiting amino acids; pair with grains for complementarity [2].
• Polyphenol- and fibre-containing legume supporting prebiotic intake and gut microbiome diversity.
• Non-heme iron source where vitamin C co-ingestion can markedly improve absorption [3].
• Soaking and sprouting reduce phytates and can improve zinc and iron bioavailability [1].

Food Context

Synergies

• Pair with grains for complete amino acid profile; grain–legume complementarity improves essential amino-acid coverage.
• Pair with vitamin C-rich foods to enhance non-heme iron absorption [3].
• Soaking and sprouting reduce phytates in legumes and grains, improving mineral bioavailability [1].

Preparation

• Soak at about 60°C (warm water) with pH ~6.0 (lemon/vinegar) for optimal phytate reduction; endogenous phytase activity peaks near these conditions [1].
• Soak 12–24 hours, then cook thoroughly to reduce phytates and improve mineral bioavailability.

Essential Amino Acid Profile

Black Beans provide a strong plant protein source but are not a complete protein.

Notable amino acids:

• Lysine

Limiting amino acids:

• Methionine and cysteine (DIAAS ~65–70)

Protein pairing strategy:

Black Beans are rich in lysine but relatively low in sulfur-containing amino acids. Combining with grains such as rice, oats, or barley helps create a more balanced essential amino acid profile.

Recipes

1 recipe containing this food

Black Bean & Sweet Potato Vegetable Chilli

A fibre-rich bean and vegetable chilli with warming spices and slow carbohydrates for steady energy and satiety.

Nutrient Tables (per 100 g)

Core nutrients

Nutrient	Amount per 100 g	% RDA per 100 g
Energy	85 kcal	—
Protein	5.4 g	—
Total fat	0 g	—
Saturated fat	0 g	—
Carbohydrates	15.4 g	—
Fibre	3.8 g	—

Key micronutrients

Nutrient	Amount per 100 g	% RDA per 100 g
Iron	1.1 mg	6.2%
Calcium	31 mg	3.1%

Reference intakes: US Dietary Reference Intakes for adults (19–50 years; using the higher of male/female values where they differ).

Data provenance (core / micronutrient panel): USDA FoodData Central, BLACK BEANS, FDC ID 2075490, API, per 100 g edible portion, last checked 2026-03-14

Substances

Substances in this food: editorial (Overview / literature) plus analytical (nutrition table).

20 substances in this food

Cu²⁺

Copper

Cofactor in redox enzymes; dopamine β-hydroxylase; iron metabolism interplay

Histidine

Essential AA; precursor to histamine; roles in enzyme active sites

Fe²⁺

Iron

Oxygen transport; dopamine synthesis (tyrosine hydroxylase cofactor)

Isoleucine

Essential BCAA; energy metabolism; complements leucine/valine

Leucine

Essential BCAA; mTOR signaling; protein synthesis; cognitive load support

Lysine

Essential AA; limiting in many cereals; complements legumes

Mg²⁺

Magnesium

Enzymatic cofactor (>300 reactions); neurotransmitters; mitochondria; redox balance

Mn²⁺

Manganese

Cofactor for MnSOD (SOD2); mitochondrial antioxidant defense

Methionine

Essential AA; precursor to SAMe via methylation cycle

Phenylalanine

Essential AA; precursor to tyrosine → catecholamines

PO₄³⁻

Phosphorus (Phosphate)

Structural phosphate in ATP, phosphocreatine, phospholipids, DNA/RNA, and signalling

K⁺

Potassium

Electrolyte for nerve transmission, muscle function, and blood pressure regulation

Threonine

Essential AA; structural proteins; mucin production

Tryptophan

Serotonin/melatonin precursor; NAD+ pathway substrate; LAT1 transport dynamics

Valine

Essential BCAA; supports protein balance and neurotransmitter transport competition

Vitamin B1 (Thiamine)

Mitochondrial glucose metabolism; ATP synthesis; rapid turnover in CNS

Vitamin B6 (Pyridoxine → PLP)

PLP cofactor for neurotransmitter synthesis; relies on brain PDXK activation

Vitamin B9 (Folate; 5-MTHF)

One-carbon metabolism; methylation; homocysteine recycling

Zn²⁺

Zinc

Cofactor in neurotransmission and antioxidant enzymes; dopamine modulation

Ca²⁺

Calcium

Bone health; neurotransmission; interacts with vitamin D and K2

References

[1] Soaking and sprouting reduce phytates and can improve zinc and iron bioavailability. Greiner & Konietzny 1999. Purification and characterization of a phytate-degrading enzyme from germinated oat (Avena sativa)

[2] Black beans are polyphenol-rich legumes that support gut health within diverse plant-forward dietary patterns. Mariotti & Gardner 2019. Dietary Protein and Amino Acids in Vegetarian Diets—A Review

[3] Pair with vitamin C-rich foods to enhance non-heme iron absorption. Hallberg & Brune 1989. Iron absorption in man: ascorbic acid and dose-dependent inhibition by phytate