Salt Reduction in a Model High-Salt Akawi Cheese: Effects on Bacterial Activity, pH, Moisture, Potential Bioactive Peptides, Amino Acids, and Growth of Human Colon Cells

J Food Sci. 2016 Apr;81(4):H991-H1000. doi: 10.1111/1750-3841.13260. Epub 2016 Feb 26.

Abstract

This study evaluated the effects of sodium chloride reduction and its substitution with potassium chloride on Akawi cheese during storage for 30 d at 4 °C. Survival of probiotic bacteria (Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium longum) and starter bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus), angiotensin-converting enzyme-inhibitory and antioxidant activities, and concentrations of standard amino acids as affected by storage in different brine solutions (10% NaCl, 7.5% NaCl, 7.5% NaCl+KCl [1:1], 5% NaCl, and 5% NaCl+KCl [1:1]) were investigated. Furthermore, viability of human colon cells and human colon cancer cells as affected by the extract showing improved peptide profiles, highest release of amino acids and antioxidant activity (that is, from cheese brined in 7.5% NaCl+KCl) was evaluated. Significant increase was observed in survival of probiotic bacteria in cheeses with low salt after 30 d. Calcium content decreased slightly during storage in all cheeses brined in various solutions. Further, no significant changes were observed in ACE-inhibitory activity and antioxidant activity of cheeses during storage. Interestingly, concentrations of 4 essential amino acids (phenylalanine, tryptophan, valine, and leucine) increased significantly during storage in brine solutions containing 7.5% total salt. Low concentration of cheese extract (100 μg/mL) significantly improved the growth of normal human colon cells, and reduced the growth of human colon cancer cells. Overall, the study revealed that cheese extracts from reduced-NaCl brine improved the growth of human colon cells, and the release of essential amino acids, but did not affect the activities of potential bioactive peptides.

Keywords: Akawi cheese; Caco-2 cell line; bioactive peptides; human colon cell line; salt reduction.

MeSH terms

  • Amino Acids / metabolism*
  • Antioxidants / pharmacology
  • Bacteria / drug effects*
  • Bacteria / growth & development
  • Bacteria / metabolism
  • Bifidobacterium / drug effects
  • Bifidobacterium / growth & development
  • Bifidobacterium / metabolism
  • Caco-2 Cells
  • Cell Line, Tumor
  • Cheese / analysis*
  • Cheese / microbiology
  • Colon / drug effects*
  • Colonic Neoplasms / diet therapy
  • Colonic Neoplasms / drug therapy
  • Food Storage / methods
  • Humans
  • Lactobacillus / drug effects
  • Lactobacillus / growth & development
  • Lactobacillus / metabolism
  • Peptides / pharmacology*
  • Peptidyl-Dipeptidase A / metabolism
  • Potassium Chloride / pharmacology*
  • Probiotics
  • Salts
  • Sodium / administration & dosage
  • Sodium / pharmacology
  • Sodium Chloride / administration & dosage
  • Sodium Chloride / pharmacology*
  • Sodium Chloride, Dietary / administration & dosage
  • Sodium Chloride, Dietary / pharmacology
  • Streptococcus thermophilus / drug effects
  • Streptococcus thermophilus / growth & development
  • Streptococcus thermophilus / metabolism

Substances

  • Amino Acids
  • Antioxidants
  • Peptides
  • Salts
  • Sodium Chloride, Dietary
  • brine
  • Sodium Chloride
  • Potassium Chloride
  • Sodium
  • Peptidyl-Dipeptidase A