Protective effect of grape by-product-fortified breads against cholesterol/cholic acid diet-induced hypercholesterolaemia in rats
Correspondence to: Sylwia Mildner-Szkudlarz, Department of Food Science and Nutrition, Poznań University of Life Sciences, Ul. Wojska Polskiego 28, PL-60-637, Poznan, Poland. E-mail: firstname.lastname@example.org
New breads fortified with two different forms of grape by-products, namely dried powdered skins (PGP) and freeze-dried extract therefrom (EGP), were characterised and their protective effect against hypercholesterolaemia in rats was studied.
The phenolic compound profiles of supplemented breads were dominated by epicatechin and catechin together with appreciable amounts of dimeric procyanidins. Sensory evaluation of enhanced breads revealed that a maximum of 6% PGP or 1.4% EGP could be incorporated to prepare acceptable products. Intake of high-cholesterol/cholic acid diet containing 6% PGP- or 1.4% EGP-fortified bread increased fresh stool weight and significantly reduced protein and fat digestion but did not negatively affect animal growth. PGP- and EGP-fortified breads diminished the negative impact of high-cholesterol/cholic acid diet, lowering total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), lipid peroxidation, glucose and leptin levels, preventing visceral fat accumulation and increasing high-density lipoprotein cholesterol and plasma ferric-reducing antioxidant power levels. Since control bread feeding significantly lowered TC, LDL-C and lipid peroxidation compared with high-fat diet, it may suggested that not only grape by-products but also another components in bread were related to lipid metabolism.
These results demonstrate that intake of both PGP- and EGP-fortified sourdough mixed rye breads might contribute to a reduction of cardiovascular risk. © 2013 Society of Chemical Industry