title: Protection of sunflower seed and sunflower meal protein with malic acid and heat: effects on in vitro ruminal fermentation and methane production.
abstract: BACKGROUND
  Combined malic acid-heat treatments of protein supplements have been shown to reduce ruminal protein degradation, but there is no information on their possible influence on ruminal fermentation and methane emissions. This study aimed to investigate the effects of the treatment of sunflower meal (SM) and sunflower seed (SS) with malic acid and subsequent drying at 150°C for 1 (MAL1) or 3 h (MAL3) on in vitro rumen fermentation and methane emission using ruminal fluid from sheep as inoculum.
  
  
  RESULTS
  Compared with untreated samples, the MAL3 treatment reduced (P < 0.05) the dry matter effective degradability (DMED) by 78% and 46% for SS and SM, respectively, indicating heat damage. The MAL1 treatment reduced the DMED of SS by 22%, but did not affect (P > 0.05) total volatile fatty acid production for any feed. This treatment also increased (P < 0.05) the propionate proportion (by 17.7% and 15.6% for SS and SM, respectively) and decreased (P < 0.05) methane production (by 15.5% and 11.3%, respectively) and ammonia-N concentrations (by 26.5% and 14.5%, respectively).
  
  
  CONCLUSIONS
  The MAL1 treatment was effective in reducing both ammonia-N concentrations and methane emissions without depressing SS and SM fermentation, but more research is needed to formulate environmentally cleaner diets for ruminants. © 2016 Society of Chemical Industry.
authors.affiliation: Departamento de Producción Agraria, Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040, Madrid, Spain.
authors.forename: Jorge Leonardo
authors.initials: JL
authors.lastname: Vanegas
authors.affiliation: Departamento de Producción Agraria, Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040, Madrid, Spain.
authors.forename: Maria Dolores
authors.initials: MD
authors.lastname: Carro
authors.affiliation: Departamento de Producción Agraria, Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040, Madrid, Spain.
authors.forename: Maria Remedios
authors.initials: MR
authors.lastname: Alvir
authors.affiliation: Departamento de Producción Agraria, Escuela Técnica Superior de Ingenieros Agrónomos, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040, Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: González
mesh_terms: D000641:Ammonia / Q000032:analysis; D000821:Animal Feed; D000818:Animals; D004032:Diet / Q000662:veterinary; D005232:Fatty Acids, Volatile / Q000096:biosynthesis; D005285:Fermentation; D006368:Helianthus; D006358:Hot Temperature; D008293:Malates / Q000494:pharmacology*; D008697:Methane / Q000096:biosynthesis; D009584:Nitrogen / Q000032:analysis; D010940:Plant Proteins / Q000187:drug effects / Q000378:metabolism*; D012417:Rumen / Q000378:metabolism*; D012639:Seeds / Q000737:chemistry*; D012756:Sheep
chemical_list: D005232:Fatty Acids, Volatile; D008293:Malates; D010940:Plant Proteins; D000641:Ammonia; C030298:malic acid; D009584:Nitrogen; D008697:Methane
keywords: heat; malic acid; methane; protein protection; sunflower meal; sunflower seed