Comparison of acid and enzymatic hydrolyses of oat bran ß-glucan at low water content

Juhani Sibakov (Corresponding Author), O. Myllymäki, T. Suortti, Anu Kaukovirta-Norja, P. Lehtinen, Kaisa Poutanen

Research output: Contribution to journalArticleScientificpeer-review

17 Citations (Scopus)

Abstract

The effect of acid- or enzyme-catalysed hydrolysis on partial depolymerisation of β-glucan in oat bran was studied. Hydrolyses were performed at relatively low water content (50% dry matter) using high shear mixing in a twin-screw extruder. The hydrolysed oat brans were extracted with hot water and centrifuged to obtain a water-soluble phase and an insoluble residue. The time-dependent gelling of the water-soluble phase was monitored for 14 weeks at 5 °C. Acid-hydrolysis required a short reaction time (3 min) to depolymerise the β-glucan molecules from their original average Mw of 780,000 to 34,000 g/mol. After acid-hydrolysis, β-glucan had low polydispersity (4.0–6.7). Longer incubation time (3–4 h) was needed for enzymatic depolymerisation of the β-glucan molecules down to 71,000–49,000 g/mol. Enzymatic hydrolysis resulted in high polydispersity (19.0–24.2). The concentration and Mw of β-glucan significantly affected the gelling of hot water extracts. At 1.4–2.0% β-glucan concentration, solutions of β-glucan molecules with Mw > 50,000 g/mol agglomerated rapidly, whereas solutions of smaller molecules (34,000–49,000 g/mol) remained as stable dispersions for longer. Gelling was strongly concentration-dependent and at 1.4 to 1.6% beta-glucan concentration gelling occurred after 7 to 12 weeks of storage, whereas at 1.8 to 1.9% concentration gelling occurred already after 2 weeks of storage.
Original languageEnglish
Pages (from-to)99-108
Number of pages10
JournalFood Research International
Volume52
Issue number1
DOIs
Publication statusPublished - 2013
MoE publication typeA1 Journal article-refereed

Fingerprint

oat bran
Glucans
acid hydrolysis
glucans
enzymatic hydrolysis
gelation
water content
Acids
Water
Hydrolysis
depolymerization
hydrolysis
water
beta-Glucans
extruders
beta-glucans
screws
Avena
shears
acids

Keywords

  • ß-glucan
  • acid-hydrolysis
  • defatted oat bran
  • enzyme-hydrolysis
  • extrusion
  • soluble dietary fibre

Cite this

Sibakov, Juhani ; Myllymäki, O. ; Suortti, T. ; Kaukovirta-Norja, Anu ; Lehtinen, P. ; Poutanen, Kaisa. / Comparison of acid and enzymatic hydrolyses of oat bran ß-glucan at low water content. In: Food Research International. 2013 ; Vol. 52, No. 1. pp. 99-108.
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abstract = "The effect of acid- or enzyme-catalysed hydrolysis on partial depolymerisation of β-glucan in oat bran was studied. Hydrolyses were performed at relatively low water content (50{\%} dry matter) using high shear mixing in a twin-screw extruder. The hydrolysed oat brans were extracted with hot water and centrifuged to obtain a water-soluble phase and an insoluble residue. The time-dependent gelling of the water-soluble phase was monitored for 14 weeks at 5 °C. Acid-hydrolysis required a short reaction time (3 min) to depolymerise the β-glucan molecules from their original average Mw of 780,000 to 34,000 g/mol. After acid-hydrolysis, β-glucan had low polydispersity (4.0–6.7). Longer incubation time (3–4 h) was needed for enzymatic depolymerisation of the β-glucan molecules down to 71,000–49,000 g/mol. Enzymatic hydrolysis resulted in high polydispersity (19.0–24.2). The concentration and Mw of β-glucan significantly affected the gelling of hot water extracts. At 1.4–2.0{\%} β-glucan concentration, solutions of β-glucan molecules with Mw > 50,000 g/mol agglomerated rapidly, whereas solutions of smaller molecules (34,000–49,000 g/mol) remained as stable dispersions for longer. Gelling was strongly concentration-dependent and at 1.4 to 1.6{\%} beta-glucan concentration gelling occurred after 7 to 12 weeks of storage, whereas at 1.8 to 1.9{\%} concentration gelling occurred already after 2 weeks of storage.",
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Comparison of acid and enzymatic hydrolyses of oat bran ß-glucan at low water content. / Sibakov, Juhani (Corresponding Author); Myllymäki, O.; Suortti, T.; Kaukovirta-Norja, Anu; Lehtinen, P.; Poutanen, Kaisa.

In: Food Research International, Vol. 52, No. 1, 2013, p. 99-108.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Comparison of acid and enzymatic hydrolyses of oat bran ß-glucan at low water content

AU - Sibakov, Juhani

AU - Myllymäki, O.

AU - Suortti, T.

AU - Kaukovirta-Norja, Anu

AU - Lehtinen, P.

AU - Poutanen, Kaisa

PY - 2013

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N2 - The effect of acid- or enzyme-catalysed hydrolysis on partial depolymerisation of β-glucan in oat bran was studied. Hydrolyses were performed at relatively low water content (50% dry matter) using high shear mixing in a twin-screw extruder. The hydrolysed oat brans were extracted with hot water and centrifuged to obtain a water-soluble phase and an insoluble residue. The time-dependent gelling of the water-soluble phase was monitored for 14 weeks at 5 °C. Acid-hydrolysis required a short reaction time (3 min) to depolymerise the β-glucan molecules from their original average Mw of 780,000 to 34,000 g/mol. After acid-hydrolysis, β-glucan had low polydispersity (4.0–6.7). Longer incubation time (3–4 h) was needed for enzymatic depolymerisation of the β-glucan molecules down to 71,000–49,000 g/mol. Enzymatic hydrolysis resulted in high polydispersity (19.0–24.2). The concentration and Mw of β-glucan significantly affected the gelling of hot water extracts. At 1.4–2.0% β-glucan concentration, solutions of β-glucan molecules with Mw > 50,000 g/mol agglomerated rapidly, whereas solutions of smaller molecules (34,000–49,000 g/mol) remained as stable dispersions for longer. Gelling was strongly concentration-dependent and at 1.4 to 1.6% beta-glucan concentration gelling occurred after 7 to 12 weeks of storage, whereas at 1.8 to 1.9% concentration gelling occurred already after 2 weeks of storage.

AB - The effect of acid- or enzyme-catalysed hydrolysis on partial depolymerisation of β-glucan in oat bran was studied. Hydrolyses were performed at relatively low water content (50% dry matter) using high shear mixing in a twin-screw extruder. The hydrolysed oat brans were extracted with hot water and centrifuged to obtain a water-soluble phase and an insoluble residue. The time-dependent gelling of the water-soluble phase was monitored for 14 weeks at 5 °C. Acid-hydrolysis required a short reaction time (3 min) to depolymerise the β-glucan molecules from their original average Mw of 780,000 to 34,000 g/mol. After acid-hydrolysis, β-glucan had low polydispersity (4.0–6.7). Longer incubation time (3–4 h) was needed for enzymatic depolymerisation of the β-glucan molecules down to 71,000–49,000 g/mol. Enzymatic hydrolysis resulted in high polydispersity (19.0–24.2). The concentration and Mw of β-glucan significantly affected the gelling of hot water extracts. At 1.4–2.0% β-glucan concentration, solutions of β-glucan molecules with Mw > 50,000 g/mol agglomerated rapidly, whereas solutions of smaller molecules (34,000–49,000 g/mol) remained as stable dispersions for longer. Gelling was strongly concentration-dependent and at 1.4 to 1.6% beta-glucan concentration gelling occurred after 7 to 12 weeks of storage, whereas at 1.8 to 1.9% concentration gelling occurred already after 2 weeks of storage.

KW - ß-glucan

KW - acid-hydrolysis

KW - defatted oat bran

KW - enzyme-hydrolysis

KW - extrusion

KW - soluble dietary fibre

U2 - 10.1016/j.foodres.2013.02.037

DO - 10.1016/j.foodres.2013.02.037

M3 - Article

VL - 52

SP - 99

EP - 108

JO - Food Research International

JF - Food Research International

SN - 0963-9969

IS - 1

ER -