Micronutrients & recovery
Heat processing, particularly sterilization at high temperatures (110-120°C), can negatively impact protein quality by causing Maillard reactions that destroy essential amino acids like Lysine, Methionine, and Cysteine, thereby lowering the PDCAAS.
Be aware that ultra-high temperature (UHT) or sterilized milk products have lower protein quality scores (PDCAAS) compared to pasteurized milk. This is due to high heat destroying essential amino acids like Lysine. For general adult consumption, this difference may be negligible if total protein intake is high, but for infant formulas or specific medical nutrition, pasteurized options may offer better amino acid availability.
Milk sterilization (at 110-120°C, 20-30 min) also causes a decline in protein quality, due to a decrease in Lys, Met and Cys... PDCAAS for sterilized semi-skimmed milk was 34 % whereas it was much higher for pasteurized semi-skimmed milk (76 %).
Why this rating
The paper provides specific data points comparing sterilized vs. pasteurized milk PDCAAS, supported by references to chemical mechanisms.
Source
Protein quality evaluation twenty years after the introduction of the protein digestibility corrected amino acid score method
Joyce I. Boye et al. · British Journal Of Nutrition · 2012
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