Naslov
Utjecaj vremena skladištenja na učinkovitost aktivacije otpadnog pivskog kvasca
(Influence of storage on efficiency of activation time of waste brewer's yeast)

Autori
Emil Škrbić

Vrsta, podvrsta i kategorija rada
Ocjenski radovi, diplomski rad

Fakultet
Prehrambeno-tehnološki fakultet

Mjesto
Osijek

Datum
17.06

Godina
2011

Stranica
48

Mentor
Vinko Krstanović

Ključne riječi
otpadni pivski kvasac; vrijeme skladištenja; učinkovitost aktivacije
(waste brewer's yeast; storage duration; activation efficiecy)

Sažetak
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 - 32 h. Hydrolyses with lactic acid was carried out at the temperature range T= 48-62 °C, pH 4.8-6.0 and in the period of 12-44 h. The best results (FAN = 4917.45 mg/L) obtained with SA were at the following process conditions: T=52 °C, pH = 5.2 and t = 32 h. On the other hand, the best results (γFAN = 5789.36 mg/L) obtained with LA were at the T=55 °C, pH = 5.5 and t=44 h. In both performed acid hydrolysis, -amino N content was not detected at temperatures higher than 60 °C, suggesting the possible inactivation of yeast proteases

Izvorni jezik
Hrvatski

Znanstvena područja
Biotehnologija

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