Biofuel co-products as livestock feed - Opportunities and challenges

382Biofuel co-products as livestock feed – Opportunities and challengesTABLE 2Chemical composition of karanj cake (as % of DM)Parameter Kernel (1) EKC (2) SKC (3) Rotary pressed (4)Crude protein 20.5–24.1 24.1–28.7 30.0–34.0 24.6Ether extract 33.2–43.3 6.1–14.2 0.1–2.2 14.0Crude fibre 3.8–4.6 3.9–10.7 5.0–5.6 6.0NFE 24.5–39.7 49.9–56.4 54.3–59.9 –Total ash 2.8–3.5 3.2–7.1 4.4–6.9 5.2NDF – 18.2 18.0–28.2 37.7ADF – 10.6 1.7–20.0 11.3Karanjin – 0.29–0.32 0.01–0.19 –Ca 0.5 0.6–0.8 0.6–0.9 0.74P 0.38 0.48–0.70 0.55–0.61 0.89Notes: EKC = expeller-pressed karanj cake; SKC = solvent-extracted karanj cake; NFE = nitrogen-free extract; ADF = acid-detergent fibre; NDF = neutraldetergentfibre. Sources: (1) Natanam, Kadirvel and Ravi, 1989; Vinay and Kanya, 2008. (2) Gupta et al., 1981; Natanam, Kadirvel and Ravi, 1989; Raviet al., 2000; Prabhu, 2002; Panda, 2004; Soren et al., 2007. (3) Mandal, Banerjee and 1974; Konwar, Banerjee and Mandal, 1984; Konwar and Banerjee,1987; Gupta et al., 1981; Ravi et al., 2000; Prabhu, 2002; Panda, 2004; Soren, 2006. (4) Chandrasekaran, Kadiravel and Viswanathan, 1989.TABLE 3Amino acid composition (g/16 g N) of karanj cakescompared with soybean mealAmino acid SKC (1) EKC (2) SBM (3)Histidine 2.07 5.11 1.13Isoleucine 3.59 5.95 2.56Lysine 5.60 3.34 2.96Leucine 7.72 7.87 3.47Methionine 0.99 1.43 0.62Arginine 4.33 4.62 3.27Phenylalanine 5.22 3.64 2.24Tryptophan 0.61 – 0.60Threonine 2.64 4.13 1.73Valine 5.26 6.44 2.44Aspartic acid 10.92 6.19 –Serine 4.53 3.98 –Glutamic acid 13.45 17.56 –Proline 5.01 2.90 –Glycine 3.85 3.39 3.27Alanine 5.10 2.31 –Cystine 6.06 1.23 0.69Tyrosine 3.67 1.27 1.43Notes: EKC = expeller-pressed karanj cake; SKC = solvent-extractedkaranj cake; SBM = soybean meal. Sources: (1) Mandal and Banerjee,1975. (2) Natanam, Kadirvel and Ravi, 1989. (3) Adapted from Kellemsand Church, 1998.and Viswanathan, 1989) ranges from 6 to 24 percent,while it is 22.0–28.7 in EKC and 30.0–34.0 percent in SKC.The crude fibre (CF) level varies from 3.9 to 5.6 percent.The variation in ether extract (EE) content is mainly due tomethod of oil extraction. Usually, cakes obtained by expellerextraction have a higher EE value (9–14.5 percent), whilelower levels (0.1–2.2 percent) are found in the cake producedby solvent extraction. A summary of various reportsby different workers regarding the chemical composition ofvarious types of karanj cake are presented in Table 2.Amino acid composition is very important in determiningthe protein quality of any cake. Values for 18 aminoacids, including essential amino acids, have been reportedby various workers (Mandal and Banerjee, 1975; Parmar,Sahrawat and Mukherjee, 1976). Mandal and BanerjeeTABLE 4Mineral composition of Karanj cake compared withsoybean mealMineral Seed kernel EKC SKC SBMMacro minerals (as % in DM)Ca 0.51 0.76 0.87 0.38P 0.38 0.48 0.55 0.71Na 0.29 – 0.49 0.48K 0.27 0.23 0.20 0.15Mg 0.47 0.27 – 0.28Trace minerals (ppm)Cu 1.37 1.96 1.97 20.0Fe 3.28 14.32 17.81 150.0Co 0.27 0.09 0.15 0.16Mn 35.78 76.21 70.82 22.0Pb 0.11 0.73 1.00 –Notes: EKC = expeller-pressed karanj cake; SKC = solvent-extractedkaranj cake; SBM = soybean meal. Sources: Natanam, Kadirvel and Ravi,1989; Georgievskii, Annenkov and Samokhin, 1982.(1975) observed that the amino acid composition of karanjcake was almost similar to that of sesame, groundnut cake(except for lysine, which was higher in karanj cake) and soybeanmeal (SBM) (except for methionine, which was lowerin karanj cake). Further, karanj cake was found to be richin cystine. Amino acid values reported by various workersare presented in Table 3. The mineral composition of karanjcake (Natanam, Kadirvel and Ravi, 1989) is presented inTable 4. In comparison with SBM, karanj cake has highercalcium, phosphorus and sodium; however, the concentrationsof copper and iron are very low.Toxic compounds in karanj cakeOn the basis of chemical nature, the toxic compoundsin karanj cake can be grouped into three categories, viz.furanoflavones, tannins and trypsin inhibitors.FuranoflavonesThe furanoflavones present in karanj seed include karanjin,pongamol, pongapin, pongaglabron, kanjone and isopo-