title: Effect of technological processing and preservation method on amino acid content and protein quality in kale (Brassica oleracea L. var. acephala) leaves.
abstract: BACKGROUND
  The aim of the investigation was to evaluate the level of amino acids and quality of protein in raw and processed kale leaves.
  
  
  RESULTS
  In all samples the dominant amino acids in g kg⁻¹ raw matter were glutamic acid, aspartic acid and proline. In raw kale leaves the limiting amino acids were lysine, isoleucine and cystine with methionine, and in the remaining products also valine and leucine. Blanched kale leaves contained 88% of the amino acid content in raw leaves, 76% in cooked leaves, and 69-77% and 71-72% of initial levels in frozen and canned products, respectively. In raw, blanched and cooked leaves essential amino acids comprised 44%, 44% and 47%, respectively, of total amino acids; in frozen and canned leaves the proportions were 46% and 44%, respectively. The essential amino acid index was 97 for canned products, 100-109 for frozen leaves, and 117 for raw kale leaves.
  
  
  CONCLUSIONS
  Raw and processed (blanched or cooked) kale leaves are a good source of amino acids.
authors: Department of Raw Materials and Processing of Fruit and Vegetables, Agricultural University of Krakow, 122 Balicka Street, 30-149 Krakow, Poland. a.korus@ur.krakow.pl.
authors: Anna
authors: A
authors: Korus
mesh_terms: D000596:Amino Acids / Q000032:analysis* / Q000737:chemistry; D000601:Amino Acids, Essential / Q000032:analysis* / Q000737:chemistry; D001937:Brassica / Q000737:chemistry*; D003296:Cooking; D005511:Food Handling; D005519:Food Preservation; D061353:Food Storage; D057141:Food, Preserved; D005628:Frozen Foods; D006358:Hot Temperature / Q000009:adverse effects; D006801:Humans; D009753:Nutritive Value; D018515:Plant Leaves / Q000737:chemistry*; D014674:Plant Proteins, Dietary / Q000032:analysis* / Q000737:chemistry; D011044:Poland; D055550:Protein Stability
chemical_list: D000596:Amino Acids; D000601:Amino Acids, Essential; D014674:Plant Proteins, Dietary