title: In vitro and in vivo evaluation of the prebiotic effect of raw and roasted almonds (Prunus amygdalus).
abstract: BACKGROUND
  Almonds contain considerable amounts of potential prebiotic components, and the roasting process may alter these components. The aim of this study was to compare the in vitro fermentation properties and in vivo prebiotic effect of raw and roasted almonds.
  
  
  RESULTS
  In vitro, predigested raw and roasted almonds promoted the growth of Lactobacillus acidophilus (La-14) and Bifidobacterium breve (JCM 1192), and no significant differences were found between these two nuts. In a 4-week animal trial, daily intake of raw or roasted almonds promoted the population of Bifidobacterium spp. and Lactobacillus spp. and inhibited the growth of Enterococcus spp. in faeces and caecal contains of rats. Compared with roasted almonds, raw almonds had a greater bifidobacteria promotion effect. Besides, significantly higher β-galactosidase activity and lower β-glucuronidase and azoreductase activities in faeces or caecal contents of rats were observed with raw almonds than with roasted almonds. While, in terms of metabolic effects, the ingestion of roasted almonds resulted in significantly greater intestinal lipase activities.
  
  
  CONCLUSIONS
  Both raw and roasted almonds exhibit potential prebiotic effects, including regulation of intestinal bacteria and improved metabolic activities. The roasting process may slightly reduce the prebiotic effects of almonds but significantly improve the metabolic effects
authors.affiliation: Institute of Food Science & Technology, Fuzhou University, Fuzhou 350108, P.R. China.
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Institute of Food Science & Technology, Fuzhou University, Fuzhou 350108, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Almond Board of California, Modesto, CA 95354, USA.
authors.forename: Guangwei
authors.initials: G
authors.lastname: Huang
authors.affiliation: Institute of Food Science & Technology, Fuzhou University, Fuzhou 350108, P.R. China.
authors.forename: Wen
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Institute of Food Science & Technology, Fuzhou University, Fuzhou 350108, P.R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Ni
mesh_terms: D000818:Animals; D002432:Cecum / Q000382:microbiology; D003296:Cooking; D016983:Enterococcus / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D005766:Gastrointestinal Contents; D008297:Male; D056692:Prebiotics; D000068181:Prunus dulcis / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D013047:Specific Pathogen-Free Organisms
chemical_list: D056692:Prebiotics
keywords: almond; bacterial enzyme activities; digestive enzyme activities; fermentation profile; prebiotic effect; roasting