Moreover, WU-AX of endosperm flour are characterised by a distinctly higher substitution degree with Araf (Ara/Xyl ratio of 0.78–0.89) ( Cyran & Cygankiewicz, 2004), than those from wholemeal (Ara/Xyl ratio of 0.56–0.68) ( Hansen, Rasmussen, Bach Knudsen, & Hansen, 2003). Therefore, they represent different substrates for hydrolytic action of endoxylanases. The aim of this work was to investigate the changes in the level, arabinosylation degree and molecular features of AX from rye endosperm flours and wholemeals Verteporfin and resulting breads, to reveal the possible mechanisms of their modification. Also, the two types of commercial rye available on the market, the hybrid and population rye cultivars, which differed in the AX content,
water extract viscosity and endoxylanase activity level, were selected to compare an impact of diversity in these parameters on the extents of AX hydrolysis and solubilisation. Five hybrid (Klawo,
Stach, Konto, Koko and SMH 2703) and six population (Amilo, D. Zlote, D. Diament, Kier, Warko and Walet) cultivars of Polish winter rye were used to produce the endosperm flours and wholemeals, buy Ruxolitinib and subsequently, the endosperm and wholemeal breads. Both types of bread were produced by a straight dough method with yeast and lactic acid addition (Cyran & Ceglinska, 2011). The freeze-dried bread samples were milled in a Cyclotec 1093 mill (FOSS, Warsaw, Poland) to pass a 0.5 mm screen and stored in plastic bags with airtight closure at −20 °C, until they were analysed. Dry mass content was determined by drying samples at 105 °C for 16 h. Ash content was analysed by AACC method (46.11A), protein (N × 6.25) by the Kjeldahl method using a Kjeltec Auto 1030 analyser (Tecator, Höganäs, Sweden). The samples were analysed at least in duplicate and the results are expressed on a dry mass Liothyronine Sodium basis. The viscosity of water extracts of flours and breads was measured in a Brookfield LVDV-III Ultra cone/plate rheometer (Brookfield Engineering Laboratories Inc., Stoughton, MA, USA) maintained at 30 °C and a constant shear rate. The extracts for viscometric
measurement were obtained after centrifugation (10,000g, 20 min) of water suspensions (1:5, w/v, 1 h, 30 °C, shaking bath). α-Arabinofuranosidase and β-xylosidase activities were determined in the crude flour extract by the method described by Rasmussen, Hansen, Hansen, and Larsen (2001), using p-nitrophenyl-α-l-arabinofuranoside and p-nitrophenyl-β-d-xylopyranoside. The activities were expressed as pkatal/g. Before extraction, the flour samples (1:5 w/v) were refluxed with 80% ethanol for 1 h, to inactivate the endogenous enzymes. After cooling to room temperature, the residue was filtered, washed with 96% ethanol and dried. The hot water-extractable arabinoxylans were isolated from flour and bread samples by ethanol precipitation, after enzymatic degradation of starch and protein, according to Englyst and Cummings (1984) with some modifications.