Utjecaj amilaze različitog podrijetla na reološka svojstva tijesta

master's thesis

• Title (english): The influence of amylase from various source on dough rheological properties
• Author: Mišela Vincek
• Mentor: Duška Ćurić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Cereal Chemistry and Technology); Zagreb
• Defense date and country: 2005-07-13, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Amilaze su enzimi odgovorni za razgradnju škroba.U tijestu osiguravaju fermentirajuće šećere za kvasac uslijed čega se volumen tijesta sa nedovoljnom količinom nižih šećera povećava. Obje amilaze, cerealna i fungalna mogu se koristiti za poboljšanje fermentacijskih svojstava brašna s nedostatkom amilazne aktivnosti. Da bi odredili aktivnost nekog enzima potrebno je imati prikladnu metodu. Perten Instruments razvio je metodu nazvanu «fungalni broj padanja» koja mjeri potpunu aktivnost fungalne i cerealne alfa-amilaze. Korištenjem ove metode nije moguće odrediti izvor amilazne aktivnosti, već samo ukupni enzimatski aktivitet, i ujedno provesti klasifikaciju uzoraka prema brašnu sa nedovoljnom, dobrom ili previsokom amilaznom aktivnosti. Niske vrijednosti broja padanja ukazuju na prekomjernu količinu prirodne i/ili dodane α-amilaze što uzrokuje ljepljivost tijesta, lošu elastičnost sredine kruha, neodgovarajuću teksturu i izrazitu obojenost kore kruha. Rezultat ovog istraživanja pokazuje da odnos između FN i FFN vrijednosti nije linearan, te se stoga ne mogu pretpostaviti vrijednosti amilolitičke aktivnosti brašna, već je za svako brašno potrebno odrediti broj padanja kako bi se moglo odrediti i koje količine enzima treba dodati.

Abstract (english)

Amylases are starch degrading enzymes. They provide fermentable sugar for yeast in doughs which causes an increase of gassing power in doughs that are deficient in sugar. Both cereal and fungal α-amylases can be used to improve fermentation of flour deficient in amylase activity. In order to determine the activity of an enzyme, it is necesary to have a suitable method.Perten Instruments have developed the method, called the Fungal Falling Number. It measures the total activity of fungal and cereal α-amylase. It is not possible to detect the origin of the α-amylase activity by using this method, but only the total level of α-amylase activity, so we can classify the sample as flour with insufficient, good or high α-amylase activity. Low values for Falling Number mean excessive levels of cereal and/or added α-amylase causing sticky dough, middle of the bread poor of resilience, unappropriate texture and vividly colored crust.The research results show that the FN and FFN relation is not linear, therefore the values of the flour amylaze activity can not be assumed, but for each flour sample, it is necessary to determine the Falling Number so that the needed amount of enzymes could be determined.

• Keywords: amilaze; amilazna aktivnost brašna; fungalni broj padanja
• Keywords (english): Amylases; amylase activity of flour; Fungal Falling Number
• Language: croatian
• URN:NBN: urn:nbn:hr:159:256040
• Study programme: Title: Food Technology; specializations in: Food Engineering; Course: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo (diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-13 11:32:04