Comparison of amino acid profiles of milk, yogurt and Turkish kefir


GUZEL-SEYDIM Z. B. , Seydim A. C. , GREENE A.

MILCHWISSENSCHAFT-MILK SCIENCE INTERNATIONAL, cilt.58, ss.158-160, 2003 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 58
  • Basım Tarihi: 2003
  • Dergi Adı: MILCHWISSENSCHAFT-MILK SCIENCE INTERNATIONAL
  • Sayfa Sayıları: ss.158-160

Özet

Kefir is a fermented dairy product that is produced by culture of lactic acid bacteria and yeast contained in kefir grains. During fermentation of milk, the amino acid profile changes as a result of microbial growth. The amino acid profile of kefir is important nutritionally because this product has demonstrated antimutagenic properties. Previous researchers have indicated that milk proteins and especially those with high concentrations of sulfur amino acids are important for anticarcinogenicity. In this project, three different methods of determining amino acid concentrations were used. An acid hydrolysis method for total amino acids, a basic method for tryptophan and a performic acid oxidation for cysteine and methionine were used for determinations in samples of milk, yogurt and kefir. Results indicate that only very slight differences in amino acid profiles occurred among the 3 different products. Kefir had higher amounts of threonine (p<0.05), serine (p>0.05), alanine (p>0.05), lysine (p>0.05), and ammonia (p>0.05) than milk or yogurt. Methionine and cysteine amino acids were not significantly different among 3 samples.