What is lipoxygenase?

What is lipoxygenase?

What is lipoxygenase?


LOX stands for lipoxygenase, an enzyme naturally present in wheat and some other grains. It catalyzes oxidation of carotenoids (color pigments like lutein) and vitamin E (tocopherols) — meaning that during dough mixing and early fermentation, much of the yellow-gold color and antioxidant activity can be lost. It also oxidizes polyunsaturated fatty acids and produces hydroperoxides. It’s highest concentration is in the germ

low-LOX grains are varieties that naturally have reduced or null lipoxygenase activity, preserving:

  • More natural color (richer golden crumb)
  • Higher antioxidant retention
  • Better nutritional quality (especially vitamin E and carotenoids)

Lower LOX plus richer antioxidant compounds (like lutein, ferulic acid, phenolics) creates natural color and nutrient stability.

Grain Comparison: LOX Activity and Nutrient Preservation

Grain / Type

Typical LOX Activity

Effect on Color (Carotenoids)

Effect on Vitamin E (Tocopherols)

Notes / Best Uses

Durum wheat (Triticum turgidum var. durum)

Very Low

Excellent color retention (bright golden hue)

Minimal oxidation of tocopherols

Ideal for golden breads, pasta, flatbreads. Excellent for blending.

Hard white wheat (T. aestivum)

Low–Moderate

Retains light creamy color; mild LOX bleaching

Retains most vitamin E

Great for artisan loaves with lighter crumb; excellent nutritional balance.

Soft white wheat

Low

Retains natural creamy tone

Good antioxidant retention

Works well for pastries, lighter sandwich breads.

Spelt (T. spelta)

Moderate–Low

Slight bleaching but generally stable

Good tocopherol preservation

Nutty flavor; lower gluten strength but good nutrient retention.

Rye (Secale cereale)

Moderate (different enzyme profile)

Naturally darker color masks oxidation

Good stability

Ferments well; nutrient-dense; beneficial in blends.

Barley (Hordeum vulgare)

Varies by cultivar (some LOX-deficient)

Good carotenoid retention, especially in LOX-null varieties

Good vitamin E stability

Excellent for nutrition-focused blending.

Oats (Avena sativa)

Low overall

Minimal impact on color

Strong antioxidant capacity (avenanthramides)

Excellent for boosting nutritional density in blends.

Hard red wheat (T. aestivum)

High

Loses yellow pigment quickly during mixing

Greater tocopherol oxidation

Rich flavor but higher LOX — more pigment and nutrient loss unless freshly milled and gently mixed.

Einkorn (T. monococcum)

Very Low

Excellent carotenoid retention

Excellent stability

Best color + nutrient stability of all wheats


 

Einkorn (Triticum monococcum)

  • LOX Activity: Very low -> significantly lower than modern bread wheats (T. aestivum).
  • Research findings:
    • Studies (e.g., Hidalgo et al., J. Cereal Sci., 2016; Leenhardt et al., J. Agric. Food Chem., 2006) show einkorn’s LOX enzyme levels are naturally suppressed, which helps retain its rich golden-yellow pigment (lutein).
  • Implication: Einkorn holds color and antioxidants extremely well; ideal for nutrient-dense golden loaves.

 

Emmer (Triticum dicoccum)

  • LOX Activity:  Low–moderate, depending on variety.
  • Findings:
    • Emmer has slightly higher LOX than einkorn, but lower than modern red and white wheats.
    • Retains color and antioxidants relatively well during dough development.
    • Nutrient profile (especially tocopherols, lutein, magnesium) remains robust.

 

Spelt (Triticum spelta)

  • LOX Activity: Moderate–Low (similar to emmer).
  • LOX present but often offset by higher antioxidant compounds (like phenolics).
  • Retains creamy color, less bleaching than modern wheats.

 

Khorasan (Kamut® / Triticum turgidum ssp. turanicum)

  • LOX Activity: Low -> similar to durum (its close relative).
  • Findings:
    • Rich yellow color from high lutein content is preserved well.
    • Low LOX helps protect carotenoids and vitamin E.


Ancient grains tend to have lower LOX, because

  • Modern bread wheats (T. aestivum) were bred for yield and baking performance, not for enzyme suppression — leading to higher LOX.
  • Ancient grains (einkorn, emmer, spelt, khorasan, durum) retain older genetic variants (often Lpx-B1.1 null or less expressed), meaning less pigment oxidation.


Rye (Secale cereale) is a grass grown extensively as a grain. It is a member of the wheat tribe (Triticeae) which includes cereals wheat and barley. Hence, rye is not wheat, but a related cereal grain

    • It’s structure depends more on starch gelation, acidity control and pentosans
    • It has a low LOX activity, but its oxidative strengthening from LOX plays a smaller role
    • For rye, acidity (pH drop during fermentation) is far more important than enzymatic oxidation.

 

At Silo and Stone, we use high quality organic fresh-milled wheat (einkorn, spelt, khorasan, soft and hard white), as well as rye to create a balanced whole wheat loaf with increased flavor depth, grain diversity and subtle fiber complexity.

 

For those that want a scientific read:

Lipoxygenases (LOXs): Will turning off this genetic switch help safeguard the flavor and nutritional quality of stored lipid-rich staple foods?

Wheat lipoxygenase activity induces greater loss of carotenoids than vitamin E during breadmaking