master's thesis
Paste properties of acetylated cross-linked starches isolated from diferent varieites rye

Tomislav Petrešin (2011)
Josip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Department of Food Technologies
Sub-department of Carbohydrates Technology
Metadata
TitleSvojstva pasti dvostruko modificiranih škrobova izoliranih iz različitih sorti raži
AuthorTomislav Petrešin
Mentor(s)Jurislav Babić (thesis advisor)
Abstract
U prehrambenoj industriji škrob se često koristi kao dodatak pri proizvodnji različitih proizvoda. Međutim, primjena nativnog škroba u velikoj mjeri je ograničena zbog nekih svojstava kao što su retrogradacija, sinereza, promjena viskoznosti i teksture tijekom skladištenja i dr. Stoga sve veću primjenu imaju modificirani škrobovi koji se proizvode tretiranjam škroba različitim kemijskim, fizikalnim te enzimskim postupcima. Cilj rada bio je prirediti dvostruko modificirane škrobove izolirane iz tri sorte raži (Conduct, Eho Kurz i Octavia) acetiliranjem acetanhidridom (8 % u odnosu na s. tv. škroba) te umrežavanjem sa natrijevim tripolifosfatom (2,5 %, odnosno 5 % u odnosu na s. tv. škroba). Nakon priprave modificiranih škrobova ispitivana su reološka svojstva pasti (nativnih i modificiranih škrobova) Brabenderovim mikrovisoko analyzerom, kapacitet bubrenja te indeks topljivosti. Rezultati istraživanja pokazali su da dvostrukim modificiranjem škrobova raži (acetiliranjem te umrežavanjem) dolazi do povišenja ili sniženja vrijednosti viskoznosti paste, ovisno o sorti raži i koncentraciji reagensa za umrežavanje. Modificirani škrobovi imali su više vrijednosti % kidanja škrobnih pasti. Modifikacijom su se snizile temperature želatinizacije, osim u slučaju škroba Octavia koji je acetiliran i umrežen s 5 % STPP-a. Kapacitet bubrenja (KB) i indeks topljivosti (IT) nativnih i modificiranih škrobova raži rasli su s porastom temperature. Dvostruko modificirani škrobovi raži imali su više vrijednosti kapacitete bubrenja pri svim mjerenim temperaturama u odnosu na nativni škrob.
Keywordsrye acetylation cross-linking gelatinization
Parallel title (English)Paste properties of acetylated cross-linked starches isolated from diferent varieites rye
Committee MembersDrago Šubarić
Jurislav Babić
Mirela Kopjar
Daliborka Koceva Komlenić
GranterJosip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Lower level organizational unitsDepartment of Food Technologies
Sub-department of Carbohydrates Technology
PlaceOsijek
StateCroatia
Scientific field, discipline, subdisciplineBIOTECHNICAL SCIENCES
Food Technology
Engineering
Study programme typeuniversity
Study levelgraduate
Study programmeFood Technology and Process Engineering
Academic title abbreviationdipl. ing.
Genremaster's thesis
Language Croatian
Defense date2011-06-16
Parallel abstract (English)
In food industry starch is often used as an additive to the production of various products. However the use of native starch Is largely limited due to some properties such as retrogradation, syneresis changes of viscosity and texture during storage, etc. Therefore, increasing aplications have modified starches that are produced by treating starch with various chemical, physical and enzymatic processes. The aim of this research was to prepare double modified starch isolated from three varieties of rye (Conduct, Eho Kurz i Octavia) acetylation with acetic anhydride (AA, 8%) followed by cross-linking with sodium tripolyphosphate (STPP, 2,5 either 5%). Rheological paste properties (natural and modified starch) were tested by Brabender Micro visco analyzer, and swelling power and solubility index after starch modification were determined. The results showed that dual modification of starches of rye (acetylation and cross-linking) leads to increasing or decreasing viscosity of paste, depending on the varieties of rye and concentration of cross-linked reagents. Modified starches had higher values % breakdown of starch paste. By modifying the gelatinization temperature decreased, except in the case of starch Octavia, which was acetylated and cross-linked with 5% STPP's. Swelling power (KB) and solubility index (IT) of natural and modified starches, increased with temperature increasing.
Parallel keywords (Croatian)raž acetiliranje umrežavanje želatinizacija
Resource typetext
Access conditionAccess restricted to students and staff of home institution
Terms of usehttp://rightsstatements.org/vocab/InC/1.0/
URN:NBNhttps://urn.nsk.hr/urn:nbn:hr:109:759208
CommitterSanda Hasenay