Effect of b-glucan molecular weight on rice flour dough rheology, quality parameters of breads and in vitro starch digestibility

E ec o β-glucan molecula weigh on ice lou dough heology, quali y pa ame e s o b eads and in i o s a ch diges ibili y * Pe ez-Qui ce, S., Laza idou, A., Biliade is, C.G., Ronda, F. LWT - Jou nal o Food Science and Technology. (2017) Vol 82, pp: 446-453 DOI: 10.1016/j.lw .2017.04.065. E ec o β-glucan molecula weigh on ice lou dough heology, quali y pa ame e s o b eads and in i o s a ch diges ibili y Sand a Pe ez-Qui ce1, A hina Laza idou2, Cos as G. Biliade is2, Felicidad Ronda1* 1Depa men o Ag icul u e and Fo es y Enginee ing, Food Technology, College o Ag icul u al and Fo es y Enginee ing, Uni e si y o Valladolid, A . Mad id, 44, 34004 Palencia, Spain. 2Depa men o Food Science and Technology, School o Ag icul u e, A is o le Uni e si y o Thessaloniki, P.O. Box 235, Thessaloniki, G eece, 541 24. * Co esponding au ho : [email p o ec ed]; Tel: +34979108339; Fax: +34979108200 Abs ac The s udy aimed a in es iga ing he e ec s o molecula weigh (peak molecula weigh , Mp, 83, 192 and 650 kDa) and le el (1.3, 2.6 and 3.9 g/100 g lou basis) o en iched in β-glucan (BG) concen a es ( om oa and ba ley) added in o ice lou glu en- ee (GF) doughs on hei iscoelas ic and pas ing p ope ies, as well as he quali y pa ame e s o b ead and he in i o s a ch diges ibili y. A pu i ica ion p ocess o a comme cial BG concen a e, ollowed by an acid hyd olysis s ep we e employed o educe he con en o in e e ing excipien s (e.g. mal odex ins) and ob ain p epa a ions wi h a ange o molecula weigh s. BG-en iched GF b eads o imp o ed quali y, ha can ul il he EFSA claims (inges o 3 g o BG pe day wi h a daily b ead in ake o ∼200 g o b ead), we e ob ained, exhibi ing slowe s a ch diges ibili y (in i o assay) dependen on he molecula weigh and concen a ion o BG. Wi h he highe Mp BG used, showing he la ges impac on dough heology cha ac e is ics and ha ing a g ea e po en ial o heal h bene i s, highe speci ic olume and lowe b ead c umb ha dness we e no ed among he GF b eads. The medium and lowes Mp BG also had an in luence on dough heological beha io and b ead quali y a ibu es. The apidly a ailable glucose o he b ead dec eased om 81g/100 g o 72g/100 g as esul o he 3.9g/100 g addi ion o he highes Mp BG in he GF o mula ions. Keywo ds: Glu en ee b ead; pas ing p ope ies; oscilla o y es , c eep- eco e y es ; diges ible s a ch. 1. In oduc ion In ecen yea s β-glucans (BG) ha e ecei ed signi ican consume and esea ch a en ion because hei consump ion has been linked wi h ce ain heal h bene i s ecognized by EFSA (EFSA 2011). These heal h claims ha e la gely con ibu ed o inc eased consump ion o ce eal based oods, such as b eads, mu ins, pas a and b eak as ce eals, mos ly whole lou p oduc s (Wole e e al., 2010). Howe e , celiacs canno inges whea , ba ley o e en oa , he main sou ces o his die a y ibe , since hey a e no glu en- ee g ains. The BG en ichmen o glu en- ee b eads o ul il he equi emen s o he abo e EFSA claims can be achie ed by addi ion o BG concen a es ob ained om hese ce eals by means o wa e ex ac ion p ocesses ha canno co-solubilize he alle genic s o age p o eins o he p olamin ac ion (Pe ez- Qui ce, Colla & Ronda, 2014; Ronda, Pe ez-Qui ce, Angioloni & Colla , 2013; Ronda, Pe ez-Qui ce, Laza idou & Biliade is, 2015). The demand o glu en- ee (GF) p oduc s s eadily inc eases as a esul o enhanced consume educa ion on die ela ed pa hogenic condi ions. Despi e he cu en demand o de elopmen o ood p oduc s wi h imp o ed nu i ional quali y, he GF p oduc s o en ecei e only ma ginal a en ion om a nu ien - ich o mula ion poin o iew. The en ichmen o GF b eads wi h BG, does hold a special in e es among he ulne able popula ion o celiac pa ien s which also encoun e s a signi ican incidence a e o o he associa ed ch onic diseases, such as obesi y-me abolic synd ome and diabe es due o hei highe a and calo ie dense die s compa ed o he gene al popula ion (C onin & Shanahan, 1997). The unc ionali y and physiological p ope ies o ce eal BG a e s ongly ela ed o hei iscosi y, which depends on he molecula weigh (Mw), ine s uc u e, concen a ion and physical s a e o he polysaccha ide (Laza idou & Biliade is, 2007; Wole e e al., 2010). Gene ally, high Mw BG a e epo ed o enhance he iscosi y o he liquid in he uppe diges i e ac (diges a) and, he eby, i is bene icial o exe ing many physiological ac i i ies (Wood, 1994); i educes he peak blood glucose esponse (Regand, 2009) and a enua es he glycemic esponse and he in i o s a ch diges ion (Thond e, Mon o, Mish a & Hen y, 2010). O e all, he Mw and amoun o BG solubilised in he gu migh be c i ical in i s capaci y o educe glucose elease and anspo as a unc ion o he inc eased iscosi y o he diges a and educed mo ili y (Regand, Chowdhu y, Tosh, Wole e & Wood, 2011). P e ious s udies ha e shown a g ea a iabili y in he e ec o BG on dough iscoelas ic beha iou and b ead quali y cha ac e is ics o whea lou bake y i ems (B ennan & Clea y, 2007; Clea y, Ande sson & B ennan, 2007; Skendi, Biliade is, Papageo giou & Izydo czyk, 2010) and GF p oduc s (Hage e al., 2011; Laza idou, Du a, Papageo giou, Belc & Biliade is, 2007; Pe ez-Qui ce, 2014; Ronda e al., 2013), depending on dough wa e and BG con en s. A loss o quali y when GF b eads a e o i ied wi h BG is pa ially ela ed o hei Mw, as a esul o enhanced wa e -binding and iscosi y (Pe ez-Qui ce e al., 2014; Ronda e al., 2015). Thus, al hough he Mw is a key de e minan o he heal h p omo ing po en ial o BG, addi ion o high le els o high Mw BG p epa a ions can be a challenge o ood p oduce s because o hei low solubili y and high iscosi y, a ec ing de imen ally he dough handling p ope ies and he senso y a ibu es o he inal p oduc . These nega i e changes could be a oided by inco po a ing lowe BG concen a ions and/o BG p epa a ions o lowe Mw (Kennan e al., 2007). Howe e , wi h lowe Mw BG, a educ ion in physiological esponses is an icipa ed (Clea y e al., 2007). The e ec s o Mw on GF dough and b ead quali y ha e mos ly been s udied by means o comme cial BG concen a es, o en o low pu i y. In his con ex , he BG- en ichmen is accompanied by addi ion o high amoun s o o he subs ances, such as mal odex ins, p esen in he comme cial p oduc (∼72g/100 g). Mal odex ins could ha e ad e se e ec s, such as weakening o he dough ne wo k s uc u e (Wi czak, Ko us, Ziob o & Juszczak, 2010) o dough s ickiness, and he eby modi y he ue e ec s caused by BG i sel (Ronda e al., 2015). Mo eo e , mal odex ins, being s a ch hyd olysis p oduc s, can agg a a e he glycemic esponses o he inal p oduc s since hey a e a o m o eadily diges ible ca bohyd a es. Thus, a comp ehensi e s udy o he e ec s o Mw and amoun o highly concen a ed BG on GF dough and b ead p ope ies is equi ed. This s udy epo s on he en ichmen in BG o a comme cial BG concen a e by means o a pu i ica ion p o ocol and a educ ion o hei Mw by acid hyd olysis o he polysaccha ides in a pas e o m o he en iched BG p epa a ion. Unde p ope ly selec ed hyd olysis condi ions he p oduc ion o a ailo -made lowe Mw BG p epa a ion was easible. Mo eo e , his s udy aimed a in es iga ing he e ec s o Mw and le el o he BG p epa a ions in oduced in o ice lou GF doughs on hei iscoelas ic and pas ing p ope ies and he quali y pa ame e s o he esul an b eads, b ead olume and i mness. The impac o BG en ichmen on he in i o s a ch diges ibili y o b eads was also assessed. 2. Ma e ials and me hods 2.1. Ma e ials Rice lou (12.5 g/100 g mois u e, 0.46 g/100 g ash, 7.5 g/100 g p o ein, 0.49 g/100 g a and 79.1 g/100 g s a ch) was supplied by He ba Ricemills S.L.U (Ta agona, Spain). Sal , suga , and sun lowe oil we e pu chased om he local ma ke . Hyd oxyp opyl-me hyl-cellulose (HPMC) 4KM was a gi om Dow Chemical (Midland, USA). Ba ley (1→3)(1→4)-β-D-glucan (BBG)(Glucagel™), a low Mw BG, was gi en as a ee sample om DKSH (Hambu g, Ge many). The oa (1→3)(1→4)-β-D-glucan concen a e (OBG) (P omoa ™) which was a high Mw BG p epa a ion, was supplied by Bio elop AB (Kims ad, Sweden). The p oxima e composi ion o hese ma e ials as gi en by he supplie s was: o BBG, 2.52 g/100 g mois u e, 4.75 g/100 g soluble p o ein, 1.43 g/100 g ash, 1.32 g/100 g a , >85 g/100 g o al ca bohyd a es, and >72 g/100 g BG; o OBG, 6 g/100 g mois u e, 54-56 g/100 g ca bohyd a es (dex in), <4.5 g/100 g p o ein, 1-3 g/100 g ash and 0.5-1 g/100 g a , and 33-36 g/100 g BG. The glu en con en o he comme cial BBG and OBG samples was analyzed by he ELISA es based on he R5 an ibody; o OBG, he glu en con en was unde he de ec ion limi (<6.2 mg/kg), while o BBG 1.76 g/kg, which ende ed he la e BG concen a e as no glu en- ee. Ne e heless, he BBG was included in his s udy as a aw ma e ial o e alua ion o he e ec o BG Mw on he ice lou -based glu en- ee dough o mula ions since i is echnically easible o ob ain a glu en- ee ba ley BG concen a e (Ronda e al., 2013). 2.2. β-glucan isola ion and cha ac e iza ion The OBG was o ela i ely low pu i y in BG (33-36 g/100 g). Hence, o his s udy u he pu i ica ion o his p epa a ion was ca ied ou , by a modi ica ion o he me hod o Laza idou, Biliade is, Micha-Sc e as & S eele (2004) o ob ain a p epa a ion wi h much highe BG concen a ion (~70 g/100 g) as shown in Figu e 1; his concen a e was designa ed as HWB. Following he me hod o Sibako e al. (2013) wi h some modi ica ions, an amoun o his en iched HWB concen a e was subsequen ly hyd olyzed by a 8 g/100 mL phospho ic acid solu ion a 82 oC ac ing o 25 min o ob ain a second BG p epa a ion wi h a desi ed medium Mw (MWB). The hyd olysis s ep was ca ied ou a high solids le el (pas e like mix u e) o mo e e ec i ely con ol he deg ada ion a e, yielding he p e e ed Mw o he polysaccha ide. The en i e pu i ica ion/isola ion p o ocol is ou lined in de ail in Fig 1. The β-glucan con en and he appa en peak molecula weigh (Mp) o he isola ed BG p epa a ions we e de e mined using he mixed-linkage (1→3)(1→4)β-D-glucan assay ki pu chased om Megazyme (Megazyme In e na ional I eland L d., Co., B ay, I eland) as well as a high pe o mance size exclusion ch oma og aphy sys em wi h a e ac i e index de ec o , espec i ely. The unning condi ions o he ch oma og aphy and he sample p epa a ion a e desc ibed in de ail elsewhe e (Laza idou e al., 2004; Laza idou, Ma inopoulou, Ma soukas & Biliade is, 2014). The low Mw BG (LWB) p epa a ion used in his s udy o b ead en ichmen was he comme cial p oduc Glucagel (BBG), ha ing an adequa e BG con en (72 g/100 g) o he equi emen s o he p esen wo k. Figu e 1: Flowcha o pu i ica ion o he comme cial β-glucan and hyd olysis p ocess. MW: Molecula Weigh ; HWB: β-glucan o high molecula weigh ; MWB: β-glucan o medium molecula weigh . 2.3. Dough p epa a ion and b eadmaking A s aigh dough p ocess was pe o med o he b eadmaking using he ollowing ing edien o mula ion exp essed on a 100 g ice lou basis: 6 g oil, 5 g suc ose, 2 g HPMC, 1.8 g sal and 3 g d ied yeas . The le els o BG inco po a ed in o his o mula ion we e 0 (con ol), 1.3, 2.6 and 3.9 g/100 g ( ice lou basis) o pu e BG by adding di e en amoun s o BG p epa a ions acco ding o hei BG con en s and added on op o he o he ing edien s. The amoun s o added wa e o he dough we e adap ed acco ding o he BG le el based on he indings o ou p e ious wo k (Ronda e al., 2015) and we e 92, 105, 120 and 130 g/100 g ( ice lou basis) wi h inc easing BG con en om 0 o 3.9 g/100 g. Dough heological es s we e pe o med wi hou inclusion o yeas in he o mula ed doughs in o de o ob ain s able eadings (a oiding CO2 e olu ion). BG samples we e hyd a ed in ho wa e (40-45 ºC) p io o hei mixing wi h he emaining dough ing edien s. The GF dough and b eadmaking p ocedu es a e desc ibed in de ail elsewhe e (Ronda e al., 2015). A e baking, b eads we e emo ed om he pan and s o ed o one hou a oom empe a u e be o e any analysis. 2.4. E alua ion o dough heology 2.4.1. Fundamen al heology Oscilla o y and c eep- eco e y es s we e ca ied ou a leas in duplica e and iplica e, espec i ely wi h a RheoS ess 1 heome e (The mo Haake, Ka ls uhe, Ge many) ollowing he same p ocedu e desc ibed in de ail elsewhe e (Ronda e al., 2013; 2015). A s ess sweep om 0.1 o 200 Pa a 1 Hz and 25 oC was pe o med o es ablish he linea iscoelas ic egion (LVR). F equency sweep da a we e i ed o a powe law model as p e iously desc ibed by Ronda e al. (2013). The eco ded iscoelas ic pa ame e s, G1’ and G1’’, and an δ1, ep esen he elas ic and iscous moduli and he loss angen , espec i ely, a a equency o 1 Hz. The a, b and c exponen s quan i y he dependence o he dynamic moduli and he loss angen on he oscilla ion equency. C eep es s we e pe o med by imposing a s ep o shea s ess o 50 Pa, exceeding he LVR, o 60 s. In he eco e y phase, he s ess was suddenly emo ed and he sample was allowed o 180 s o eco e he elas ic (ins an aneous and e a ded) pa o he de o ma ion. C eep da a a e desc ibed in e ms o c eep compliance, J, which is de ined as he s ain di ided by he s ess applied. The da a om c eep and eco e y es s we e modelled o he 4- and 3-pa ame e Bu ge ’s models, espec i ely (Laza idou e al., 2007; Ronda e al., 2013). Conce ning he calcula ed pa ame e s, J0 is he ins an aneous compliance, J1 is he e a ded elas ic o iscoelas ic compliance, λ1 is he e a da ion ime and η0 is he s eady iscosi y (es ima ed om he c eep s ep). Addi ionally, Jmax is he maximum c eep compliance ob ained a he end o he c eep s ep and Js eady, he s eady-s a e compliance in he eco e y s ep, calcula ed by sub ac ing he compliance alue a he e minal egion o cu e (whe e dough eco e y eached equilib ium) om he Jmax. Reco e y (%) was calcula ed as 100·( Js eady/Jmax). 2.4.2. Pas ing p ope ies Viscome ic p o iles o o mula ed and hen lyophilized ice lou doughs (wi hou yeas ) we e ob ained wi h a Rapid Visco Analyse (RVA-4, Newpo Scien i ic, Wa iewood, Aus alia) using he ICC S anda d 162 p o ocol. The e-hyd a ed eeze-d ied samples we e ans e ed in o RVA canis e s and p ocessed as p e iously desc ibed by Ronda e al. (2013). These es s we e ca ied ou in iplica e. 2.5. E alua ion o b ead quali y B ead olume was de e mined in duplica e by a Volscan p o ile 300 analyse (S able Mic osys ems, Godalming, UK). B eads we e weighed immedia ely a e emo al om he pan once cooled down. C umb ha dness was de e mined in duplica e wi h a TA-XT2 ex u e analyse (S able Mic osys ems, Su ey, UK) using he so wa e “Tex u e Expe ”. An aluminum 20 mm diame e cylind ical p obe was employed in a comp ession es a 1 mm/s speed es and de o ma ion le el up o 50 %. C umb ha dness (N) was calcula ed om he maximum o ce o he cu es. Analysis was ca ied ou a 20 ± 3 ºC on b ead slices, wi h 20 mm hickness, aken om he cen e o each loa . 2.6. In i o s a ch diges ibili y o b eads In i o s a ch enzyma ic diges ibili y o b eads was measu ed acco ding o he modi ied me hod o Englys , Hudson & Englys (2000). The hyd olyzed glucose Simila esponses we e no ed o he se back iscosi ies. In gene al, i is clea ha wi h inclusion o high amoun s o soluble die a y ib es in he composi e mix u es, he in e molecula associa ions wi hin he s a ch ne wo k upon cooling a e weakened. 3.3. E alua ion o b ead quali y The speci ic olume o b eads was posi i ely a ec ed by he addi ion o BG a low le els; a 1.3 g/100 g b ead speci ic olume inc eased (17–22 %) compa ed o he con ol b ead, ega dless he molecula weigh o he BG p epa a ion. Howe e , o i ica ion o he GF doughs wi h highe amoun s o BG (up 3.9 g/100 g) educed successi ely he loa olume (Table 1). The lowes speci ic olume was p esen ed o b eads en iched wi h 3.9 g/100 g LWB (Table 1 and Figu e 3). The e o e, i seems ha he s uc u ing abili y o he BG depends on i s molecula weigh and p ima ily on i s concen a ion. The possible cause o he lowes speci ic olume o LWB could be he inc eased gela ion po en ial o he BG ha inc eases he igidi y o he doughs and he eby esul s in a lowe dough expansion and loa olume. The less p onounced loa olume educ ion wi h inc easing con en s o MWB and HWB p epa a ions de i ed om he OBG concen a e could be a ibu ed o he educ ion and/o elimina ion o he mal odex ins in hese samples; appa en ly, he addi ion o mal odex ins has a s ong weakening e ec on s uc u e o GF dough and inc eases i s suscep ibili y o de o ma ion (Wi czak e al., 2010). O he esea che s ha e epo ed a signi ican dec ease up o 50 % in loa olume and heigh wi h he inclusion o BG in o whea -based b ead o mula ions (B ennan & Clea y, 2007; Clea y e al., 2007; Hage e al., 2011); such a decline was mo e p onounced a highe le els o o i ica ion. Skendi e al. (2010) demons a ed a dependence o loa olume on he molecula size and concen a ion o ba ley BG added o he dough, as well as on he quali y o whea lou base used in he o mula ions. O he au ho s ob ained he g ea es educ ion in loa olume when a high Mw BG was added o whea lou doughs (Clea y e al., 2007). B ennan & Clea y (2007) obse ed ha en ichmen o dough wi h soluble BG p epa a ions impa s educed ex ensibili y, which would limi o en sp ing. BG added o whea doughs can in e up he con inui y o he glu en ne wo k (Skendi e al., 2010). In ou case, he wa e amoun added o he GF doughs was adjus ed in such a way ha BG en iched doughs showed nei he he highes consis ency no he lowes compliances. The speci ic olume was co ela ed posi i ely (p<0.001) o an δ1 alues ( =0.91) and o he exponen s a ( =0.91) and b (p<0.05, =0.69) as well as nega i ely o c (p<0.001; =-0.81) and he pe cen age o compliance eco e y (p<0.05; =-0.70). The abo e ela ions mean ha he highe he iscous-like beha io o he GF dough, wi h a s uc u e mo e dependen on equency, and he lowe he a io o elas ic o o al de o ma ion unde an applied s ess, he highe he speci ic olume o he b ead, a leas wi hin he ange o alues ob ained o hese a iables in he cu en wo k. CONTROL (0%BG) 3.9% LWB 3.9% MWB 3.9% HWB Figu e 3. C oss-sec ions o glu en- ee b eads o mula ed wi h β-glucan p epa a ions a he maximum le el es ed (3.9 g/100 g lou ). BG: β-glucan; Mw: Molecula Weigh ; LWB: β-glucan o low molecula weigh (83 kDa); MWB: β-glucan o medium molecula weigh (192 kDa); HWB: β-glucan o high molecula weigh (650 kDa). En iched b eads a he highes BG con en showed he highes c umb ha dness (Table 1); he highes alue among he h ee di e en BG p epa a ions was no ed o he LWB samples, p obably due o he lowe loa olume and he g ea e gelling po en ial o he LWB; co ela ion analysis showed ha c umb ha dness was nega i ely co ela ed wi h speci ic olume (p<0.001; =-0.89). A highe b ead olume usually co esponds o highe amoun s o ai e ained in he dough s uc u e du ing p oo ing and baking, and his gene ally yields lowe c umb ha dness. Hage e al. (2011) also ound a so ening e ec on he c umb wi h he inco po a ion o an oa BG p epa a ion. C umb ha dness was u he co ela ed (nega i ely) wi h he exponen a (p<0.01; =-0.80) and he an δ1 (p<0.01; =-0.77) alues o he dough, and posi i ely co ela ed wi h he c (p<0.05; =0.69) pa ame e o he dough 3.4. In i o s a ch diges ibili y o b eads Table 2 shows he e ec o inclusion o he h ee BG p epa a ions a he lowes and highes concen a ion s udied on he in i o s a ch diges ibili y o he GF ice b eads. F ee suga glucose (FSG) con en s (g/100 g d y basis) o b eads en iched wi h he lowes Mp BG we e signi ican ly lowe (p<0.05) among all b eads analyzed. Taken in o accoun ha suga was added o he dough o mula ion a 5 g/100 g le el ( ice lou basis) he low inal concen a ion (<1 g/100 g) ound in b eads means ha suc ose was la gely used by yeas du ing e men a ion. Rapidly a ailable glucose (RAG) and apidly diges ible s a ch (RDS) alues o b eads wi h he lowes concen a ion o BG (1.3 g/100 g) we e no di e en om he con ol ega dless o he BG molecula weigh . Howe e , wi h inc ease o BG concen a ion he e was a signi ican dec ease o apidly eleased glucose om s a ch by he diges i e enzymes o MWB and HWB o i ied b eads, in ag eemen wi h p e ious in i o s udies (S ama aki e al., 2016). Fo RAG and RDS, he lowes alues we e achie ed a he highes concen a ion o HWB, 72 g/100 g and 64 g/100 g e sus 81 g/100 g and 72 g/100 g in he con ol b ead, espec i ely (Table 2), in ag eemen wi h a p e ious s udy (Hage e al., 2011). The diges ible s a ch (DS) showed a small dec ease in he p esence o BG, ye la ge in cases o LWB and HWB inclusion a 3.9 g/100 g le el. As o he esis an s a ch (RS), a he highes o i ica ion le els o BG, ega dless o Mp, he e was a signi ican inc ease. The s a ch diges ibili y a e index (SDRI), which quan i ies he s a ch diges ion a e i espec i e o he b ead o al s a ch con en , showed a signi ican dec ease in b eads o i ied wi h MWB and HMW p epa a ions when he highes BG le els we e used; his e ec was enhanced wi h he inc ease o molecula weigh o he BG p epa a ion; a 3.9 g/100 g addi ion o HWB he SDRI dec eased om 93 % (con ol) o 85 %. These obse a ions ela ed o he educed a e and ex en o s a ch diges ion in he in i o s a ch diges ibili y assays can be a ibu ed o iscosi y e ec s, as modula ed by he concen a ion and molecula weigh o he BG p epa a ion (C x Mw ); such ends ha e been also epo ed by Regand e al. (2011) o simila ood p oduc s. Table 2. S a ch ac ions FSG and RAG exp essed as g/100 g o o al solids o he glu en- ee b eads (in i o diges ion). BG Mp CONTROL LWB MWB HWB SE BG le el (g/100 g lou basis) 0 1.3 3.9 1.3 3.9 1.3 3.9 FSG 0.84 b 0.32 a 0.38 a 0.96 b 0.60 ab 0.93 b 0.96 b 0.2 RAG 80.5 c 79.5 c 78.0 bc 80.0 c 75.5 b 77.7 bc 71.5 a 1.4 RDS 71.7 c 71.3 c 69.8 bc 71.2 c 67.4 b 69.1 bc 63.5 a 1.3 SDS 4.9 b 2.4 a 1.8 a 3.8 ab 7.6 c 4.9 b 8.6 c 1.2 DS 76.5 c 73.7 ab 71.6 a 75.0 bc 75.0 bc 74.4 b 72.0 a 1.3 RS 0.0 a 1.4 abc 4.6 d 0.6 ab 1.6 bc 2.0 bc 2.9 cd 1.0 TS 76.3 ab 75.1 ab 76.2 ab 75.6 ab 76.6 b 76.1 ab 74.9 a 1.0 SDRI 93.3 c 94.8 c 91.6 bc 95.5 c 88.0 ab 91.4 bc 85.0 a 0.02 BG: β-glucan; Mp: peak molecula weigh ; LWB: β-glucan o low molecula weigh (83 kDa); MWB: β-glucan o medium molecula weigh (192 kDa); HWB: β-glucan o high molecula weigh (650 kDa). FSG: F ee glucose and suc ose; RAG = apidly a ailable glucose; RDS = apidly diges ible s a ch; SDS = slowly diges ible s a ch; DS = diges ible s a ch; RS = esis an s a ch; TS = o al s a ch; and SDRI = s a ch diges ion a e index (100· RDS/TS). SE: Pooled s anda d e o om ANOVA analysis. Values wi h a le e in common in he same column a e no signi ican ly di e en (p > 0.05). The es s we e made a leas in quad uplica e. 4. Conclusions This s udy examined he po en ial impac o h ee di e en BG samples a ying in hei molecula weigh and o igin (oa and ba ley), bu o simila pu i y, on physical and nu i ional quali y o ice lou based doughs and b eads (glu en- ee). A pu i ica ion p ocess o a comme cial BG concen a e was adop ed o he o i ica ion o dough o mula ions o a oid he in e e ence o o he excipien s p esen in his p epa a ion and make clea he ue impac o he BG addi ion in he composi e o mula ion. Fu he mo e, i allowed he p oduc ion o BG samples o educed molecula weigh by con olled acid hyd olysis o BG in a concen a ed aqueous pas e o m. This s udy demons a es he easibili y o p oduc ion o BG- en iched GF b eads wi h accep able quali y a ibu es ha can ul ill he EFSA claim (choles e ol lowe ing e ec o daily consump ion o 3 g BG wi h ~ 200 g o o i ied b ead). I also indica ed ha o mula ion op imiza ion (molecula weigh and concen a ion o BG, as well as dough wa e con en ) is equi ed o p ope ly a ge o speci ic quali y a ibu es o he end-p oduc , while ensu ing he ull heal h po en ial o his physiologically ac i e polysaccha ide. Mo eo e , he use o high molecula weigh BG p epa a ions in bake y i ems mus be p e e ed as i is well documen ed he ela ion be ween iscosi y enhancemen and hypoglycemic and hypocholes e olemic e ec s. Appa en ly, in he p esen s udy, a maximum o i ica ion le el ( o jus i y he heal h claim equi emen s) accep able quali y cha ac e is ics (c umb ex u e) we e no ed wi h he highes molecula weigh p epa a ion. 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