{
  "abstract": "Background\n\nThis study evaluated the chemical composition, protein secondary structure, crude protein (CP) solubilization, and in-vitro amino acid (AA) digestibility of three Kenyan full-fat soybean (FFSB) samples (S1, S2, S3) with unknown processing histories and compared with Canadian samples: raw FFSB, extruded FFSB at 160.0 °C, and FFSB roasted at 136.7 °C, 151.7 °C, or 154.4 °C. Protein structure was characterized using attenuated total reflectance-Fourier transform infrared spectroscopy. A two-phase in-vitro digestion model was used to determine CP solubilization and AA digestibility. Observed in-vivo standardized ileal digestibility (SID) values from a study using FFSB roasted at 136.7 °C were regressed on corresponding in-vitro AA digestibility values to generate predicted SID values.Results\n\nThermal processing reduced trypsin inhibitor activity (TIA) in Canadian FFSB from 17.42 TIU/mg in raw FFSB to 3.85 TIU/mg in extruded FFSB and to 4.77, 4.59, and 2.30 TIU/mg in samples roasted at 136.7, 151.7, and 154.4 °C, respectively. In contrast, Kenyan Samples 1, 2, and 3 had residual TIA values of 8.00, 6.00, and 12.00 TIU/mg, respectively. Protein secondary structure differed among samples (P < 0.001), with the 136.7 °C-roasted sample having greater aggregated β-sheet and β-turn contents and lower random coil content than most samples. CP solubilization differed among samples at each digestion time point (P < 0.001). At the end of the intestinal phase, processed Canadian samples had greater CP solubilization than raw FFSB but did not differ from one another, whereas Kenyan Samples 2 and 3 were comparable to Canadian raw FFSB. In-vitro AA digestibility differed among samples for all AA (P ≤ 0.001). For mean total AA digestibility, the 154.4 °C and 151.7 °C-roasted sample had the highest digestibility; Kenyan Sample 1 was greater than Samples 2 and 3, and Sample 3 did not differ from raw FFSB. The regression model showed agreement at the mean level but larger prediction errors for lysine, aspartic acid, and proline, indicating AA-specific limitations.Conclusions\n\nOverall, processing conditions and ingredient origin influenced FFSB quality, with roasting at 151.7-154.4 °C producing favorable structural and digestibility responses. The variability observed among Kenyan samples highlights the need for routine quality assessment of commercial FFSB before feed formulation.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada.",
    "Department of Animal Sciences, Pwani University, Kilifi, Kenya.",
    "Department of Animal Production, University of Nairobi, Nairobi, Kenya.",
    "Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada. ekiarie@uoguelph.ca."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Felix M Njeri"
    },
    {
      "affs": [
        0
      ],
      "name": "Adriana Leticia Ciola"
    },
    {
      "affs": [
        0
      ],
      "name": "Lonita A Manoa"
    },
    {
      "affs": [
        1
      ],
      "name": "Munene Kithama"
    },
    {
      "affs": [
        2
      ],
      "name": "Joyce G Maina"
    },
    {
      "affs": [
        2
      ],
      "name": "Charles K Gachuiri"
    },
    {
      "affs": [
        0
      ],
      "name": "Lee-Anne Huber"
    },
    {
      "affs": [
        3
      ],
      "name": "Elijah G Kiarie"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/evgrj65q73azw.bib",
  "cited_by": 0,
  "doi": "10.1186/s40104-026-01512-w",
  "fulltext_url": "https://europepmc.org/articles/PMC13726081",
  "id": "evgrj65q73azw",
  "issns": [
    "1674-9782",
    "2049-1891"
  ],
  "landing_url": "https://europepmc.org/article/MED/42968187",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Research"
    ],
    [
      "openalex",
      "1103|Animal Nutrition and Physiology"
    ]
  ],
  "openalex": "W7225050701",
  "pdf_url": "https://europepmc.org/articles/PMC13726081?pdf=render",
  "pmcid": "PMC13726081",
  "pmid": "42968187",
  "published": "2026-11-02",
  "publisher": "BMC",
  "ris": "https://research.draconitic.com/paper/evgrj65q73azw.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T15:20:53Z",
      "native_id": "MED:42968187",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42968187"
    },
    {
      "first_seen": "2026-11-05T12:22:29Z",
      "native_id": "PMC13726081",
      "source": "pmc",
      "url": "https://doi.org/10.1186/s40104-026-01512-w"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "openalex:1103|Animal Nutrition and Physiology",
      "subfield": "zoology-behaviour"
    }
  ],
  "title": "Full-fat soybean origin and thermal processing affect protein secondary structure, in vitro digestion kinetics, and predicted standardized ileal amino acid digestibility in broiler chickens.",
  "title_text": "Full-fat soybean origin and thermal processing affect protein secondary structure, in vitro digestion kinetics, and predicted standardized ileal amino acid digestibility in broiler chickens.",
  "type": "peer-reviewed",
  "updated_at": "2026-11-05T12:22:29Z",
  "url": "https://research.draconitic.com/paper/evgrj65q73azw",
  "venue": "Journal of animal science and biotechnology",
  "versions": []
}