Does the pelleting process affect the nutritive value of a pre-starter diet for suckling piglets? Ex vivo studies on mineral absorption.
BACKGROUND
The effects of pelleting on the extent of the Maillard reaction (MR) and on calcium, magnesium and zinc solubility and absorption were analysed in a conventional pre-starter diet for suckling piglets. Development was tested measuring colour, absorbance (280/420 nm), fluorescence, residual free lysine, furosine, hydroxymethylfurfural (HMF) and furfural contents before and after pelleting. Fluorescence, absorbance and mineral solubility were also measured after in vitro digestion of diets. The effects on mineral absorption were tested using Caco-2 cells.


RESULTS
MR indexes confirmed the development of the reaction during the pelleting of this particular diet compared with the meal diet. The CIE-Lab colour parameters showed a decrease in luminosity (L*) and progress of the colour to the red zone (a*) in the pelleted diet. A 36% decrease in free lysine content was observed. Significant correlations were observed between fluorescence intensity and furosine levels, HMF and furfural. The pelleting process did not modify calcium and magnesium solubility after in vitro digestion, but soluble zinc increased. The efficiency of calcium and zinc transport across Caco-2 cell monolayers was greater in the pelleted diet.


CONCLUSIONS
Evidence of MR development is shown, resulting in various nutritional consequences. Optimisation of pelleting could result in a better formulation of diets for feedstuffs.
Delgado-Andrade
Cristina
C
Unidad de Nutrición Animal, Estación Experimental del Zaidín, (CSIC), Camino del Jueves, 18100 Granada, Spain. cdelgado@eez.csic.es
Rufián-Henares
José A
JA
Nieto
Rosa
R
Aguilera
José F
JF
Navarro
M Pilar
MP
Seiquer
Isabel
I
D000821:Animal Feed / Q000032:analysis*; D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D000833:Animals, Suckling; D018938:Caco-2 Cells; D002118:Calcium / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics; D002463:Cell Membrane Permeability; D003116:Color; D004063:Digestion; D005453:Fluorescence; D005662:Furaldehyde / Q000031:analogs & derivatives / Q000032:analysis; D006358:Hot Temperature / Q000009:adverse effects; D006801:Humans; D007408:Intestinal Absorption; D008239:Lysine / Q000031:analogs & derivatives / Q000032:analysis; D008274:Magnesium / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics; D015416:Maillard Reaction; D008903:Minerals / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics*; D009753:Nutritive Value; D012995:Solubility; D013552:Swine; D015032:Zinc / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics
D008903:Minerals; C018948:furosine; C008046:5-hydroxymethylfurfural; D005662:Furaldehyde; D008274:Magnesium; D015032:Zinc; D008239:Lysine; D002118:Calcium