Nutrient contents of kale ( Brassica oleraceae L. var. acephala DC.)

• Published in: Food chemistry Vol. 96; no. 4; pp. 572 - 579
• Main Authors: Ayaz, Faik A., Glew, Robert H., Millson, M., Huang, H.S., Chuang, L.T., Sanz, Carlos, Hayırlıoglu-Ayaz, S.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-06-2006; Elsevier
• Subjects: Acid; Amino acid; amino acid composition; aspartic acid; Biological and medical sciences; Black cabbage; Brassica oleracea; Brassica oleraceae var. acephala; citric acid; Fatty acid; fatty acid composition; food analysis; food composition; Food industries; fructose; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; glucose; glutamic acid; Kale; leaves; linoleic acid; lysine; malic acid; Mineral; omega-3 fatty acids; omega-6 fatty acids; seed oils; sucrose; Sugar; Mineral; Acid; Amino acid; Fatty acid; Black cabbage; Kale; Brassica oleraceae var. acephala; Sugar; Vegetables; Lipids; Fatty acids; Inorganic element; Brassica oleracea var. acephala; Cruciferae; Dicotyledones; Angiospermae; Nutrient; Spermatophyta; Cabbage
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2005.03.011

Fructose, glucose and sucrose, as the major soluble sugars and citric and malic acids, as the major organic acids, were identified and determined in kale (
Brassica oleraceae L. var.
acephala DC., black cabbage) leaves. Fructose was the predominant sugar (2011 mg
100 g
−1 dry wt) identified, followed by glucose (1056 mg
100 g
−1 dry wt) and sucrose (894 mg
100 g
−1 dry wt). The contents of citric and malic acids were at 2213 and 151 mg
100 g
−1 dry wt in the leaves. The 16:0, 18:2
n
−
6 and 18:3
n
−
3 fatty acids were the most abundant fatty acids in the leaves. Considering the level of these fatty acids, 18:3
n
−
3 was found to be the highest (85.3 μg
g
−1 dry wt), contributing 54.0% of the total fatty acid content. Linoleic acid (18:2
n
−
6), being the second most abundant fatty acid was present at 18.6 μg
g
−1 dry wt, contributing 11.8% of the total fatty acid content. In the seed oil of kale, 22:1
n
−
9 was the most abundant fatty acid (4198 μg
g
−1 dry wt, 45.7%), with 18:2
n
−
6 (1199 μg
g
−1 dry wt, 12.3%) and 18:1
n
−
9 (1408 μg
g
−1 dry wt, 14.8%) being the second next most abundant fatty acids. The most abundant amino acid was glutamic acid (Glu) which was present at 33.2 mg
g
−1 dry wt. Aspartic acid, which was the second most abundant amino acid, was present at 27.6 mg
g
−1 dry wt and accounted for 10.2% of the total amino acid content of kale leaf. The amino acid content was assessed by comparing the percentages of the essential amino acids in kale leaf versus those of a World Health Organization (WHO) standard protein. The protein of kale leaf compares well with that of the WHO standard. Only one amino acid, lysine, had a score that fell below 100%; the lysine score of kale leaf was 95%. This study attempts to contribute to knowledge of the nutritional properties of the plant. These results may be useful for the evaluation of dietary information.