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Extraction of Non-Protein Amino Acids from Cyanobacteria for Liquid Chromatography-Tandem Mass Spectrometry Analysis
Published on: December 9, 2022
Available versus digestible dietary amino acids
Shane M Rutherfurd1, Paul J Moughan
1Riddet Institute, Massey University, Palmerston North, New Zealand. S.M.Rutherfurd@massey.ac.nz
The British Journal of Nutrition
|October 31, 2012
Summary
True ileal digestible amino acids may not accurately predict available amino acids in processed foods. Specific analytical methods are needed for lysine, methionine, and cysteine due to processing-induced changes.
Area of Science:
- Animal Nutrition
- Food Chemistry
- Analytical Chemistry
Background:
- Available amino acids are crucial for protein synthesis, absorbed from the gut.
- True ileal digestible amino acids measure unabsorbed amino acids at the ileum.
- Accurate amino acid analysis is vital for predicting nutritional availability.
Purpose of the Study:
- To evaluate the accuracy of true ileal digestible amino acid estimates in processed foods.
- To identify challenges in analyzing specific amino acids like lysine, methionine, and cysteine.
- To highlight the need for specialized analytical strategies for processed foodstuffs.
Main Methods:
- Assessing the impact of heat processing on amino acid availability.
- Investigating the reaction of lysine, methionine, and cysteine during processing and analysis.
- Comparing standard analysis with newer methods like the guanidination assay for lysine.
Main Results:
- Heat processing can create unavailable lysine derivatives that revert during analysis, overestimating available lysine.
- Methionine and cysteine can oxidize to forms (methionine sulphone, cysteic acid) that lead to overestimation if present initially.
- The true ileal digestible reactive lysine assay offers accurate lysine determination in processed foods.
Conclusions:
- True ileal digestibility estimates may not reliably predict available amino acid content in processed foods.
- Standard analytical methods can lead to inaccuracies for specific amino acids.
- Specialized analytical approaches are necessary to accurately determine available amino acids in processed foods.
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