Globally, soybeans are grown to meet the needs for animal and human nutrition, oil extraction, and use in multiple industrial applications. Decades of soybean research, innovative farming methods, and the use of higher yielding resistant seed varieties have led to increased crop yields. Globally, soybean producers have utilized enhanced processing methods to produce nutritious high-quality meal and extracted oil for use in animal feed and within the food industry. Soybeans contain highly digestible proteins and are processed using various mechanical and chemical techniques to produce high quality animal feed ingredients. Defatted soybean meal (DSM) is usually prepared by the solvent extraction process of soybeans, whereby almost all oil content is removed. When oil is not extracted, full-fat soybean meal (FFSBM) is created. This form provides an excellent source of dietary energy by retaining the lipid component and is very useful in animal feeds by reducing the need for adding exogeneous lipids. However, some anti-nutritional factors (ANF) are present in FFSBM if not properly heat treated before inclusion in the finished feed. These ANF adversely affect the internal organ function and overall growth performance of the animal. Among these ANF, protease inhibitors are most important, but can be readily destroyed with optimal thermal processing. However, if the process protocols are not followed precisely, excessive heat treatment may occur, resulting in both reduced protein quality and amino acid bioavailability in the meal. Conversely, insufficient heat treatment may result in the retention of some ANF in the meal. Thermally resistant ANF can be greatly reduced in the bean and meal when dietary enzyme supplementation is included in the finished feed. This approach is cost-effective and most commonly utilized commercially. After processing, the soybean meal quality is often measured using in vitro methods performed at commercial analytical laboratories to assess the nitrogen solubility index (NSI), protein dispersibility index (PDI), urease activity (UA), and protein solubility in potassium hydroxide. Once properly processed, FFSBM or DSM can be utilized optimally in the diets of poultry and aquaculture to enhance the economic viability, animal nutrition, production performance, and the quality and nutritional value of the meat and/or eggs produced.

On a global scale, the poultry industry expands its wings in terms of meat and egg production to the masses. However, this industry itself requires a sustainable and permanent supply of different inputs, one of which is poultry feed and nutrition. Soybean is a versatile protein that is offered to poultry in different inclusion rates in commercial diets after being processed using various thermal and mechanical processing methods. Conventional commercial soybean meal is usually prepared by the extraction of oil from whole soybeans using solvents, producing a meal that has approximately 1% crude fat. Without oil extraction, full-fat soybean (FFSBM) is produced, and it is an excellent source of dietary energy and protein for poultry with a nutritional profile of 38–40% protein and 18–20% crude fat, on average. FFSBM has less crude protein (CP) than solvent-extracted soybean meal (SE SBM) but higher metabolizable energy due to higher fat content. Alternatively, extruded expeller processing produces defatted soybean meal containing approximately 6–7% crude fat. Studies have demonstrated that FFSBM can be used in poultry diets to improve poultry nutrition, performance, and quality of the poultry meat and eggs produced. This review aims to evaluate the nutrition and use of meals prepared from conventional and high-oleic soybeans using various feed processing methods.

High-oleic (HO) soybean may serve as a value-added feed ingredient to enrich poultry meat due to its fatty acid content. However, the amino acid (AA) nutrient digestibility of soybean meal (SBM) made from these soybeans has yet to be determined. The objective of this study was to determine apparent ileal AA digestibility (AID) and standardized ileal AA digestibility (SID) of high-oleic full-fat (HO-FF) SBM compared to normal oleic full-fat (NO-FF), normal oleic extruded expeller (NO-EE), and solvent-extracted SBM (SE-SBM) in broilers. A nitrogen-free basal diet (NFD) was fed to 1 treatment group with 10 chicks/cage to determine basal endogenous losses (BEL). Titanium dioxide was used as an inert marker. The test diets contained 57.5% of the basal NFD and 42.5% of 1 of the 4 soybean sources. A total of 272 Ross-708 male broilers were placed in 40 battery cages with 5 treatments and 8 replicates per treatment. A common starter diet was provided to all the chickens for 14 d. Experimental diets were provided as a mash for 9 d before sample collection. Chickens were euthanized with CO₂ on d 23, and contents of the distal ileum were collected, frozen, and freeze-dried. The BEL were similar to the values found in the literature. At d 23, broilers fed the SE-SBM had the highest body weight gain and best FCR compared to chickens fed the HO-FF and NO-FF treatments (P < 0.001). Broilers fed the SE-SBM and NO-EE experimental diets had (P < 0.001) higher apparent ileal AA digestibility and AA SID than broilers fed the HO-FF and NO-FF treatments. In conclusion, the SID of AA from HO-FF is similar to the digestibilities of other full-fat soybeans found in the literature and is lower than that of NO-EE and SE-SBM.

High oleic (HO) soybeans may serve as a value-added feed ingredient; providing amino acids and estimating their dietary energy value for broilers is essential. In this study, we determined the apparent metabolizable energy (AME), AME corrected for zero nitrogen retention (AMEn), digestibility, and nitrogen (N) retention of HO full-fat (HO-FF) soybean as compared to solvent-extracted soybean meal (SE-SBM), normal oleic full-fat (NO-FF) and extruded expeller (NO-EE) soybean. A total of 240 Ross-708 male broilers were selected, with 8 replicates per treatment and 6 chicks per cage. The AME and AMEn were estimated using the difference method with a 30% inclusion of test ingredients using a corn-soy reference diet with partial and total excreta collection. The index method with partial excreta collection used titanium dioxide as an inert marker. The same starter diet was provided for all birds for 14 d, followed by the reference and assay diets for the next 6 adaptation days. Total excreta were collected twice a day for 3 d. The AME and AMEn values determined for the HO-FF and NO-FF were higher (P < 0.001) than the NO-EE and SE-SBM. The AME of SE-SBM and NO-EE were similar with both methods, but the AMEn of SE-SBM was lower than the NO-EE only with the partial collection method. The agreement between AME and AMEn values determined by partial and total excreta collection analysis was 98%. Data from the total excreta collection method yielded higher AME and AMEn values (P < 0.001) than those from the partial collection method. In summary, HO-FF and NO-FF soybean meals had similar AME and AMEn values. The HO-FF soybean had 39 and 24% higher AME and AMEn than SE-SBM. Hence, high oleic full-fat soybean meal could serve as a valuable alternative feed ingredient to conventional SE-SBM meals in broiler diets, providing additional energy while providing amino acids and more oleic acid to enrich poultry meat products.

The effects of high oleic oil full-fat (HO-FF) soybean meal (SBM) on broiler meat quality could lead to value-added food products. This experiment evaluated the effects of dietary normal oleic extruded expelled (NO-EE), normal oleic full-fat (NO-FF), or HO-FF SBM on live performance, carcass and parts yield, and breast fatty acid composition. Diets were formulated to be isoenergetic and isonitrogenous. A total of 540 Ross-708 male broilers were raised on floor pens with 18 broilers/pen and 10 replicates/treatment. Data were analyzed in a completely randomized design. Chickens were fed with a starter (0-14 d), grower (15-35 d), or a finisher diet (36-47 d) up to 47 d. Chickens were weighed at 7, 14, 35, and 47 d. At 48 d, 4 broilers per pen were processed. Breast samples were collected and evaluated for quality and fatty acid content. Broilers fed diets with NO-EE were heavier (P < 0.05) than chickens fed diets with full-fat SBM (NO-FF and HO-FF) at d 7, 14, 35 while feed conversion ratio (FCR) of NO-EE was best (P < 0.05) at 7 and 47 d. Carcass yield was also higher for broilers fed NO-EE than the other treatments. Diet did not affect parts yield, breast meat color, cooking, drip loss, white stripping, or SM quality parameters. More breast fillets without wooden breast (score 1) were observed (P < 0.05) for NO-FF than the other 2 treatments. The breast meat fatty acid profile (g fatty acid/100 g of all fatty acids) was significantly affected (P < 0.001) by diet. Broilers fed the HO-FF SBM diet had 54 to 86% more oleic acid, 72.5% to 2.2 times less linoleic acid, and reduced stearic and palmitic acid levels in the breast meat than NO-FF and NO-EE. In conclusion, feeding HO-FF to broilers enriched the oleic acid content of their breast meat while reducing the saturated fatty acid content relative to the NO-FF and NO-EE treatment groups.

Soybeans (Glycine max) are a preferred source of plant-based proteins and oil in various applications in foods and feeds. When soybean is converted to soybean meal (SBM), the quality is determined by the protein content and its digestibility. Protein digestibility is reduced by anti-nutritional factors like trypsin inhibitors (TI) and processing. The abundant genetic variations in soybean germplasm affect the quantitative trait of protein content. This study analysed the effect of location and planting dates on genetically identical soybeans grown in North Carolina (NC) and then compared the nutritional traits to similar commonly grown soybean varieties in other locations in the USA. The soybeans were analysed using NIRS and wet chemistry. It was found that soybean protein content ranged from 38.14% to 44.92% among the different varieties grown in three different locations in NC. Similarly, TI levels ranged between 28.22 and 33.11 mg g−1 among these varieties. The same varieties, when planted as either a full season or double crop, had different TI levels and were also impacted by planting location. However, there were no significant differences in the TI levels between the varieties and planting seasons. Furthermore, no significant difference in protein content among the varieties within the planting dates was found. Compared to soybeans grown in other parts of the USA, the average crude protein (CP) content was similar to those grown in Arkansas and Minnesota. The TI levels were significantly higher than those grown in Ohio, similar to that of Arkansas, and significantly lower than that of Minnesota.