Energy utilization of by-products from the soybean oil industry by broiler chickens: acidulated soapstock, lecithin, glycerol and their mixture

Abstract

Acidulated soy soapstock (ASS) and lecithin (LEC) are by-products from processing soy oil (SO) for human consumption, whereas glycerol (GLY) can be obtained through the transesterification of vegetable oils during the production of biodiesel. These are valuable by-products for poultry feeds that have been underutilized in many parts of the world. One study was conducted to estimate the AME n of ASS, LEC, GLY as well as of their mixture (MIX: 85% ASS, 5% LEC and 10% GLY). Two hundred and sixty Cobb 500 female broilers of 20 days of age were housed in steel wire battery cages in a controlled temperature room for broilers. A completely randomized (energy sources x fat inclusion level) factorial design was applied, with 4 replicates of three birds per treatment. Birds were fed a corn-soybean meal control diet without supplemental fat or with the addition of 2, 4, or 6 % of the four energy sources. Total excreta collection was performed from 26 to 28 days. The AME n values of by-products were calculated using regression analysis as well as by the difference method. The average AME n values calculated by regression analysis were : 9,232, 7,502, 5,447 and 8,404, whereas results with the difference method were: 7,951, 6,579, 3,979 and 8,101 kcal/kg for, in both cases for ASS, LEC, GLY and MIX, respectively. It is concluded that these energy sources can be for broilers and that there are significant differences between the methods used to estimate AME n of fats.

Influence of the inclusion of co-products of the soy oil industry in poultry diets on nutrient digestibility, growth performance, and production

“…Similarly, Kim et al (2013) reported no differences in TTAR of N and EE in broilers fed diets that contained 50 g GLYC/kg but GE retention increased with GLYC supplementation. Also, Peña et al (2014) reported that the inclusion of Groesbeck et al (2008) reported that TTAR of GE and N were not affected when up to 60 g GLYC/kg was included in the diet, in agreement with the results reported herein. All this information indicates that the effects of GLYC on nutrient retention are very limited and of little practical interest.…”

“…In the current research, the AME of the fats increased as the level of fat increased, probably because the ratio between the EE contained in the dietary ingredients and that of the supplemental fat was reduced (Irandoust et al, 2012). In this respect, Vieira et al (2002) and Peña et al (2014) reported in broilers that the AME of the experimental ASO source increased by 2.53 and 5.36 MJ/kg, when the level of the oil in the diet increased from 40 to 80 g/kg or from 20 to 60 g/kg, respectively. Aardsma and Parsons (2016) reported also that the TME of SO and maize oil increased by 1.01 and 2.33 MJ/kg, as the level of oil supplementation increased from 50 to 100 g/kg.…”

“…shown that the inclusion of up to 6% of lecithin increases the AME of the diet, by improving dietary fat digestibility (Sibbald et al, 1962, Polin, 1980, Peña et al 2014). …”

“…into the corresponding experimental diets at the expense (wt:wt) of the animal fat. In the formulation of the diets, no attempt was made to equalize the AME n concentration of the diets, as a consequence of differences in energy content of the two fat sources used, because the AME n of the lecithin in laying hen diets is not well established, with values ranging from 27.5 MJ/kg (Peña et al, 2014) to 35.5 MJ/kg . Two batches of experimental diets were manufactured; the first batch was used for the first four feeding periods and the second batch was used for the last three feeding periods.…”

“…Animal fats and oils are commonly used in animal feeds to increase the energy concentration of the diet, supply essential fatty acids, fat soluble vitamins, and antioxidants or improve the technological properties of the feed (Mateos and Sell, 1980b;Jones et al, 1992;Holland et al, 1998;Grobas et al, 1999;Lammers et al, 2008a;Peña et al, 2014). Three lipid co-products resulting from the biodiesel industry namely; glycerin, lecithin and re-esterified oils, have been selected for the purpose of this thesis.…”