Abstract
The objective of this work was to obtain information on Amaranthus greggii S. Wats., related to its nutritional value, its agricultural application as leaf vegetable and for animal consumption. The following variables were analyzed: dampness, ashes, protein, mineral, ethereal extract (fat), brute fiber, oxalic acid, nitrates and carbohydrates.
Introduction
One of the species of the genus Amaranthus whose study is of a high interest due to its economical and nutritional value, has been identified botanically as Amaranthus greggii S. Wats. The excellent qualities of some annual amaranth as vegetables, owing to their nutritional value and pleasant taste, have also been determined (Castañeda et al., 1987).
Experimental Area
The green material of amaranth was dried in a stove with air forced to 60 °C until stable, and was then ground and dehydrated. Different types of chemical assays were carried out: dampness, ashes by calcination in muffle at 550 °C (Pearson, 1976), proteins by the Kjeldahl method (N x 6,25) (Skoog, West and Holler, 1995); Ca and Mg by complexmetric (Hamerly et al., 1984), P and Fe by colorimetry (Jackson, 1964), ethereal extract (extraction by Soxhlet), gross fiber and oxalate following (AOAC 1984), nitrate by colorimetry (Cataldo et al., 1975) and carbohydrates (according to difference).
Results and Discussion
The chemical composition determined on dried basis of leaves of A. greggii, is detailed on Table 1; the data were compared with the data obtained by Cattaneo et al. (1994) and Arellano et al. (1992) for A. mantegazzianus and spinach.
Table 1.
Proximal Chemical Composition of the tested A. greggii, confronted with A.mantegazzianus and spinach.
It was observed that A. greggii leaves have a protein content similar to spinach and A. mantegazzianus has values which surpass other types of amaranth (Rawate,1983).
The relatively high value of ashes denotes important contents of minerals, having an outstanding content of calcium and magnesium in A. greggii, which surpasses spinach and A. mantegazzianus, although inferior to the ones found by Rawate. Comparing the value of the content of iron with other amaranths, it was observed that its content is high, the values were similar to A. mantegazzianus and superior to spinach (Castañeda et al.,1987). The percentages of phosphorus found in the foliage during the analysis were near the ones mentioned by Troiani et al. (1992).
The results obtained for nitrate and oxalate in A. greggii compared with the results obtained by Gomez et al. (1986) and Arellano et al. (1992) for A. mantegazzianus and spinach are shown in Table 2; the values are below the ones considered as toxic (Avila et al., 1987).
Table 2.
Antinutrients of the tested A. greggii, confronted with A. Mantegazzianus and spinach.
The analysis performed on Amaranthus greggii show similar values to the blanks which allows us to infer that this species is another alternative to the human diet.
References and Notes
- Association of Official Analytical Chemmists. Official Methods of Analysis of the AOAC; The Association: Washington, D.C., 1984. [Google Scholar]
- Castañeda, C.L.; Suárez, R.G.; Valdez, L.A. Evaluation of Amaranth as vegetable in comparison with spinach. Col. Nac. of Amaranth.; Mexico, 1987; pp. 150–158. [Google Scholar]
- Hamerly, J.; Marracini, J.; Piagentini, R. Course on Analytical Chemistry; El Ateneo: Bs. As, 1984; p. 1006. [Google Scholar]
- Rawate, Prabhu D. Amaranth (Pigweed): a Crop to Help Solve the World Protein Shortage. Environmentally Sound Agriculture; 1983; pp. 287–298. [Google Scholar]
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