Chemical compositions of okra (Hibiscus esculenta L.) seeds and skins

Abstract

Mature okra was obtained from Bilecik in the west region of Turkey in late August 2009 and separately, divided 0 seeds and skins. Moisture contents were immediately measured on arrival. The seeds and skins were shed using hammer mill (Brock Series 2000). The milled samples were dried at room temperature in the laboratory and packed in thick gauge polythene bags. The samples in the polythene bags held at room emperature uniil analyzed. Proximate compositions and mineral contents of the mature okra seeds and skins were separately investiga- ‘ed. Some physical properties of seeds were also evaluated. The seeds, which represent the 28.74 % of mare okra, were mainly composed by protein (28.71%), oll (22.62%), cellulose (48.67%), lignin (17.28%), ash (5.21%) and moisture (9.95%). Meanwhile, the skins of okra were composed by protein (8.30%), oil (4.42%), Cellulose (61.67%), lignin (8.28%), ash (9.93%) and moisture (10.31%). Scanning Electron Microscopy (SEM) images of the samples of grinded okra seeds and skins surface were obtained by using an EVO. 50XVP (Cart Zeiss SMT Ltd.). Chemical compositions were determined by using the Genesis 4000EDX de. tector (EDAX Inc.). The most predominant elements in the seed and skin samples were found to be K, P, Ca Mg. The elements S, Cl Al, Si were also presented in abundant amounts. GC-MS chromatography revealed ‘ that the major fatty acid of seed oil was linoleic acid (49.54%), palmitic acid (28.60%), oleic acid (16.81%). Some chemical properties such as crude protein, crude oil and crude fiber were found important due to nut. tional values. It could be concluded that mature okra skin and seed are a promising source of protein and fat as earlier reported by other researchers. It may therefore be suggested that products from okra seeds could be put into alternative uses in Turkey instead of regeneration purposes alone such as incorporation into weaning or adult foods. The information supplied on the physical characteristics of the okra seed could serve as useful tool in designing processing equipment such as dehulling and cleaning equipment. Antioxidant activi. ties in food plants are essential in this regard because they are active in inhibiting free radical reactions and consequently protect the human body against damage by reactive oxygen species. Thus, further studies are stil needed to study on the antioxidant activities that can identify the mature okra skin and seed for the benefit of mankind.