USDA-Sponsored Study Shows Oryzatein® May Improve Shelf Life of Emulsion-Based Food or Cosmetic Products
Published online March 16, 2017 — European Journal of Lipid Science and Technology
Lipid oxidation is a persistent problem in emulsion-based products, driving off-flavors, rancidity, and shortened shelf life. Antioxidants are the usual fix, but consumer demand for cleaner, more natural formulations has narrowed the list of acceptable options. This study set out to evaluate the antioxidant activity of two rice protein concentrates (RPC) in both bulk oil and oil-in-water emulsion systems.
Bulk oils were mixed with either Oryzatein® 70 (RPC1) or Oryzatein® SG-B/N (RPC2) and heated to 180°C. Researchers measured total polar compounds and triacylglycerol polymerization to track lipid oxidation relative to an untreated control.
Emulsions were formulated with RPC1 or RPC2 at 0.5% and 1.0% by weight, then subjected to accelerated oxidation for 8 days at 50°C. Oxidation was tracked through peroxide values, headspace oxygen levels, headspace volatile oxidation products, and fatty acid analysis, each compared against control.
RPC1 offered only minor protection against oxidation, and the effect wasn't significantly different from control.
RPC2 showed a consistent ability to suppress lipid oxidation:
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RPC2 at 1.0% consistently produced lower peroxide values than every other treatment, including control
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RPC2 at both 0.5% and 1.0% consistently produced lower headspace volatile oxidation products than control
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Fatty acids declined across all samples, but the decline was smaller in samples containing 1.0% RPC2.
Oryzatein® SG-B/N (RPC2) shows real promise as a natural antioxidant ingredient, with potential to extend shelf life in emulsified food and cosmetic products — think sauces, gravies, dressings, and lip stains.
Adding Oryzatein® SG-B/N at 1.0% by weight appears to meaningfully suppress lipid oxidation in emulsions — a natural option as consumers grow less accepting of artificial or synthetic ingredients.
Rice protein may offer a natural alternative to synthetic antioxidants like EDTA or BHT — helping brands move toward a cleaner label without sacrificing shelf stability.