Thermal and photo-stability of the antioxidant potential of Spirulina platensis powder.
This work aimed to evaluate the thermal and photo stability of the antioxidant potential (AP) of the Spirulina platensis biomass. Thermal stability was established at 25ºC, 40ºC and 50ºC for 60 days, in the dark, protected from light. Photo stability was evaluated using UV (15 W, λ = 265 nm) and fluorescent (20 W, 0.16 A, power factor FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) light for 90 days in capsules, glass and Petri dishes, at room temperature. The AP of the biomass in these conditions was determined at intervals (every 7 and 30 days in the studies of thermal and photo stability, respectively) using the induction of the oxidation of a lipid system by heat and aeration. In this lipid system, the biomass submitted to degradation was used as an antioxidant. The kinetics of the reaction was determined by the Arrhenius method. Thermal degradation was found to follow zero order kinetics, whereas photo degradation followed first order kinetics. The AP decreased 50% after 50 days at 25°C. At 40°C and 50°C, the AP decreased more than 50% after 35 and 21 days of exposition, respectively. The decrease of the AP of Spirulina was more sensible to UV and fluorescence light. After 30 days of exposition, the AP decreased more than 50% in all storage conditions tested. The antioxidant potential of Spirulina platensis is easily degraded when the biomass is exposed to heat and light, indicating the need for care to be taken in its storage.
Curso de Engenharia de Alimentos, Laboratório de Fermentações, Universidade de Passo Fundo - UPF, Campus I, BR 285, CEP 99001-970, Passo Fundo, RS, Brazil.
L M
LM
Colla
Curso de Farmácia, Instituto de Ciências Biológicas, Universidade de Passo Fundo - UPF, Campus I, BR 285, CEP 99001-970, Passo Fundo, RS, Brazil.
C D
CD
Bertol
Curso de Farmácia, Instituto de Ciências Biológicas, Universidade de Passo Fundo - UPF, Campus I, BR 285, CEP 99001-970, Passo Fundo, RS, Brazil.
D J
DJ
Ferreira
Curso de Farmácia, Instituto de Ciências Biológicas, Universidade de Passo Fundo - UPF, Campus I, BR 285, CEP 99001-970, Passo Fundo, RS, Brazil.
J
J
Bavaresco
Programa de Pós-graduação em Engenharia e Ciência de Alimentos, Universidade Federal do Rio Grande - FURG, Rua Engenheiro Alfredo Huch, 475, CP 474, CEP 96201-900, Rio Grande, RS, Brazil.
J A V
JAV
Costa
Curso de Engenharia de Alimentos, Laboratório de Fermentações, Universidade de Passo Fundo - UPF, Campus I, BR 285, CEP 99001-970, Passo Fundo, RS, Brazil.
T E
TE
Bertolin
D000975:Antioxidants / Q000737:chemistry* / Q000528:radiation effects; D018533:Biomass; D006358:Hot Temperature; D008027:Light; D011208:Powders; D053545:Spirulina / Q000737:chemistry*
D000975:Antioxidants; D011208:Powders