Research
Macro partitioning
High-temperature cooking and prolonged storage can decrease protein quality by reducing the bioavailability of essential amino acids, particularly lysine, through the Maillard reaction and protein aggregation.
Avoid charring or overcooking meats and grains. High-temperature methods like grilling or prolonged roasting can chemically alter amino acids (especially lysine), reducing the protein's quality. Moderate cooking is generally better for preserving bioavailability.
GoodRefutesHIGH confidence
Conversely, protein quality decreases when exposing foods to prolonged storage, heat sterilization, and high surface temperatures.
Why this rating
Supported by multiple studies cited in the review regarding lysine glycation and digestibility changes in cooked meats and grains.
Source
Understanding Dietary Protein Quality: Digestible Indispensable Amino Acid Scores and Beyond
Joseph J. Matthews et al. · Journal of Nutrition · 2025
narrative_reviewCited 25×
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