Effect of thermal processing methods on the proximate composition, gross energy, minerals and ricin content of undecorticated castor oil seed (<i>Ricinus communis</i>)

Abstract

The nutritive value of raw and thermal processed castor oil seed (Ricinus communis) was investigated using the following parameters; proximate composition, gross energy, mineral constituents and ricin content. Three thermal processing methods; toasting, boiling and soaking-and-boiling were used in the processing of the seed as a way of improving its nutritive value. The three methods achieved a drastic reduction in the ricin levels. Toasting, boiling and soaking-and-boiling reduced ricin level by 93.05%, 94.84% and 97.76% respectively. Apart from Iron and potassium the thermal processing methods significantly (P<0.05) reduced the levels of all other measured constituents. Toasting, as a processing method, achieved a higher proximate components (apart from crude protein and crude fibre), gross energy, mineral and ricin content than boiling and soaking-and-boiling methods. However, the higher level of ricin retained and the lower level of crude protein of toasted seed, make it the least preferred among the thermal processing methods, while soaking-and boiling that gave the least level of ricin and high level of crude protein is to be more preferred.

Performance of layers fed toasted, boiled or boiled and soaked castor oil seed meal (R. Communis)

“…This result shows that birds on T 3 were poor converters of feed to dozen of egg, this might be due to the high residue of ricin in the toasted meal. Nsa (2008) reported decrease in egg production as ricin content in laying birds diet increased. The improved performance of the birds on diets containing other test ingredients other than toasted seed meal, suggested enhanced nutritive value which encouraged better utilization by laying birds and could be attributed to the better detoxification of the meal (table II), similar observations were recorded by Udedibie and Mba (1994); Amaefule and Obioha (1998);Finks et al (1992); Ukachukwu and Anugwa (1995); Nsa et al (2010) for pigeon pea, pigeon pea, cowpea, soybean and castor oil seed respectively.…”

“…However, Values obtained from all the treatment methods were higher than the 21.80, 22.50 and 22.39 percent crude protein levels reported for raw kidney bean, lima bean and pigeon pea respectively (Oyenuga, 1968;Okorie et al, 1985;Apata and Ologhobo, 1994;Ukachukwu and Obioha, 1997;Ukotebi, 2002). Nsa and Ukachukwu (2009) have shown that the crude protein value of castor oil seed meal ranks with those of green seed, bambara, groundnut seed, Mucuna cochinenensis, Milletia obanensis, but lower than that of groundnut and soybean seed meal which is the richest in crude protein value among the legume species (Ene-Obong and Carnovale, 1992;Apata and Ologhobo, 1994). This indicates that all the treatment methods retain adequate protein level as a good concentrate source for livestock feeds.…”

“…The crude protein content of the toasted meal (24.55 %) was significantly (p<0.05) lower than both boiled seed meal (28.33 %) and boiled-and-soaked seed meal (26.43 %). The lower level of crude protein in toasted meal could be attributed to the dry heat which quickens the denaturation, complex bond forming with other nutrients especially carbohydrate and subsequent solubilisation of protein due to excessive heat treatment (Nsa, 2008). However, Values obtained from all the treatment methods were higher than the 21.80, 22.50 and 22.39 percent crude protein levels reported for raw kidney bean, lima bean and pigeon pea respectively (Oyenuga, 1968;Okorie et al, 1985;Apata and Ologhobo, 1994;Ukachukwu and Obioha, 1997;Ukotebi, 2002).…”

“…In Nigeria, castor oil bean is distributed in a number of the Southern States including Nsukka, Awka, Anambra, Bendel, Imo and Cross River States (Okorie et al, 1985 andRehman, 1999). The raw seed is high in protein 32.80 to 40.00 % (Okorie et al, 1985;Nsa and Ukachukwu, 2009), with an ideal amino acid profile that is moderately high in cystine, methionione, tryptophan and isoleucine (Harnold, 2002).…”

Pengaruh Waktu Perebusan Terhadap Kandungan Proksimat, Mineral Dan Kadar Gosipol Tepung Biji Kapas

“…Testa biji memiliki kandungan serat yang tinggi, kehilangan itu berarti merupakan penurunan kandungan serat kasar. Hal serupa telah dilaporkan oleh Nsa 19 . Sementara hasil penelitian Udensi, et.al 20 menyebutkan bahwa perlakuan perendaman yang diikuti dengan perebusan tidak memberikan pengaruh, kecuali pada perendaman selama 24 jam yang diikuti perebusan selama 90 menit memberikan hasil serat kasar paling rendah dibandingkan perlakuan lain, namun meningkatkan kandungan karbohidrat pada kacang kara benguk.…”