Química Nova

Autor: Silva, Vilma Mota da, Silva, Luciana Almeida, Andrade, Jailson Bittencourt de, Veloso, Márcia Cristina da Cunha, Santos, Gislaine Vieira dos
Jazyk: angličtina
Rok vydání: 2008
Předmět:
Zdroj: Repositório Institucional da UFBA
Universidade Federal da Bahia (UFBA)
instacron:UFBA
Popis: p. 901-905. Submitted by JURANDI DE SOUZA SILVA (jssufba@hotmail.com) on 2011-11-23T13:46:35Z No. of bitstreams: 1 a31v31n4.pdf: 112618 bytes, checksum: d91c23fa8bc48d4caf59cf6dd18493fc (MD5) Made available in DSpace on 2011-11-23T13:46:35Z (GMT). No. of bitstreams: 1 a31v31n4.pdf: 112618 bytes, checksum: d91c23fa8bc48d4caf59cf6dd18493fc (MD5) Previous issue date: 2008 The water content in seafoods is very important since it affects their sensorial quality, microbiological stability, physical characteristics and shelf life. In this study, thermoanalytical techniques were employed to develop a simple and accurate method to determine water content (moisture) by thermogravimetry (TG) and water activity from moisture content values and freezing point depression using differential scanning calorimetry (DSC). The precision of the results suggests that TG is a suitable technique to determine moisture content in biological samples. The average water content values for fish samples of Lutjanus synagris and Ocyurus chrysurus species were 76.4 ± 5.7% and 63.3 ± 3.9%, respectively, while that of Ulva lactuca marine algae species was 76.0 ± 4.4%. The method presented here was also successfully applied to determine water activity in two species of fish and six species of marine algae collected in the Atlantic coastal waters of Bahia, in Brazil. Water activity determined in fish samples ranged from 0.946 – 0.960 and was consistent with values reported in the literature, i.e., 0.9 – 1.0. The water activity values determined in marine algae samples lay within the interval of 0.974 – 0.979. São Paulo
Databáze: OpenAIRE