master's thesis
Study on kinetics of spent brewer's yeast hydrolysis by acid

Ivan Šimunović (2016)
Josip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Department of Process Engineering
Sub-department of Bioprocess Engineering
Metadata
TitleIspitivanje kinetike kiselinske hidrolize otpadnog pivskog kvasca
AuthorIvan Šimunović
Mentor(s)Vinko Krstanović (thesis advisor)
Abstract
Provedeno je ispitivanje uspješnosti autolize otpadnog pivskog kvasca inducirane pomoću sumporne (SA) i mliječne kiseline (LA). Cilj rada bila je procjena uspješnosti autolize inducirane anorganskom u odnosu na autolizu induciranu organskom kiselinom. Reakcijski uvjeti (pH i temperatura podešeni su tako da bi osigurali optimalne uvjete za aktivnost endoenzima kvasca kako bi proces razgradnje biopolimera kvasca tekao neometano. Proces hidrolize praćen je porastom udjela slobodnog -amino N (FAN) u hidrolizatu. Hidroliza sumpornom kiselinom provedena je u temperaturnom intervalu T = 45 - 60 °C, pri pH 5.0 - 5.4 tijekom perioda od 12 - 36 h. Hidroliza mliječnom kiselinom provedena je u temperaturnom intervalu T = 48 - 62 °C, pri pH 5.4 - 6.2 tijekom perioda od 12 - 44 h. Najbolji rezultat dobiven hidrolizam sa (SA) (3985,42 mg/L) bio je pri procesnim uvjetima T = 60 °C, pH = 5.2 i t = 36 h dok je kod hidrolize sa (LA) najbolji rezultat (7144,01 mg/L ) dobiven pri T = 55 °C, pH = 6.0 i t = 44 h. U oba slučaja ne dolazi do porasta udjela -amino N u temperaturnom području iznad 60 °C što ukazuje na moguću inaktivaciju proteolitičkog kompleksa kvasca.
Keywordsyeast brewer's yeast hydrolysis
Parallel title (English)Study on kinetics of spent brewer's yeast hydrolysis by acid
Committee MembersDarko Velić
Vinko Krstanović
Frane Čačić
Vedran Slačanac
GranterJosip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Lower level organizational unitsDepartment of Process Engineering
Sub-department of Bioprocess Engineering
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 date2016-03-10
Parallel abstract (English)
In this study, acid induced autolysis of spent brewer's yeast was carried out with sulfuric (SA) and lactic acid (LA). The aim of this study was to estimate the success of autolysis induced with inorganic acid compared to autoysis induced with organic acid. The reaction was performed at pH and temperature range which enable the optimum activity of the yeast endoenzymes, so that the process can be considered on acid induced autolysis of yeast biopolymers. Process of hydrolysis was monitored by measuring the increase in the free amino nitrogen (FAN, - amino N) concentration. Hydrolysis with sulfuric acid was conducted at the temperature range T = 45 - 60 °C, pH 5.0 - 5.4 and in the period of 12 - 36 h. Hydrolyses with lactic acid was carried out at the temperature range T = 48 - 62 °C, pH 5.4 - 6.2 and in the period of 12 - 44 h. The best results (3985,42 mg/L) obtained with (SA) were at the following process conditions: T = 60 °C, pH = 5.2 and t = 36 h. On the other hand, the best results (7144,01 mg/L) obtained with (LA) were at the T = 55 °C, pH = 6.0 and t = 44 h. In both performed acid hydrolysis, - amino N content was not detected at temperature higher than 60 °C, suggesting the possible inactivation of yeast proteases.
Parallel keywords (Croatian)kvasac pivski kvasac hidroliza
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:109:292256
CommitterIvana Šuvak