Metodología analítica para la determinación del contenido hídrico en los quistes de Artemia
Pesar y tarar 3 pequeñas cápsulas de papel de aluminio (de aproximadamente 0,1 g cada una) = T1, T2, T3; presecádas (= 2 horas en la estufa a 60°C seguido por 30 minutos en un desecador con silicagel).
Llenar cada cápsula con una muestra aproximada de 500 mg de quistes.
Determinar el peso bruto (con una precisión de 0,1 mg) = G1, G2, G3.
Colocar las cápsulas de aluminio conteniendo los quistes en una estufa (24 horas, 60°C; con silicagel); dejar enfriar durante 30 minutos en un desecador que contenga silicagel.
Determinar el peso bruto libre de agua (con una precisión de 0,1 mg) = G'1, G'2, G'3.
Calcular el contenido hidrico Wi (en porcentaje de H2O).
Calcular el valor medio de los tres replicados
Ejemplo práctico
Muestra | Peso de la cápsula de aluminio (en g) (=Ti) | Peso de la capsula de aluminio + los quistes (g) (=Gi) | Peso de la cápsula de conaluminio de + los quistes libres de agua (g) (=G'i) | % tenido en agua |
1 | 0,2158 | 0,7158 | 0,6688 | 9,2 |
2 | 0,2434 | 0,7434 | 0,6969 | 9,3 |
3 | 0,2827 | 0,7827 | 0,7365 | 9,2 |
W | 9,3 |
9. Observaciones
Las técnicas utilizadas para la determinación en agua de las semillas vegetales (ej. combustión con carbono cálcico; calentamiento con lámpara infrarroja), no son aplicables para el análisis del contenido hídrico de los quistes de Artemia; ya que a tempera turas superiores a 60°C los lípidos son vaporizados y los contenidos de los quistes (incluyendo el agua) no son fácilmente liberados por la extremadamente resistente membrana cuticular externa de la cáscara.
Densidad (g/ml) | Grados Beaumé (Be) | Salinidad (ppt) | Densidad | Grados Beaumé | Salinidad | Densidad | Grados Beaumé | Salinidad | Densidad | Grados Beaumé | Salinidad |
1.020 | 2.8 | 28.6 | 1.061 | 8.4 | 1.102 | 13.4 | 1.141 | 17.8 | |||
1.021 | 3.0 | 1.062 | 8.5 | 1.103 | 13.5 | 1.142 | 17.9 | ||||
1.022 | 3.1 | 1.063 | 8.7 | 1.104 | 13.6 | 1.143 | 18.0 | ||||
1.023 | 3.3 | 1.064 | 8.8 | 1.105 | 13.7 | 1.144 | 18.1 | ||||
1.024 | 3.4 | 1.065 | 8.9 | 1.106 | 13.8 | 1.145 | 18.2 | ||||
1.025 | 3.6 | 1.066 | 9.0 | 1.107 | 14.0 | 1.146 | 18.3 | ||||
1.026 | 3.7 | 1.067 | 9.2 | 1.108 | 14.2 | 1.147 | 18.5 | ||||
1.027 | 3.8 | 1.068 | 9.3 | 1.109 | 14.3 | 1.148 | 18.6 | ||||
1.028 | 4.0 | 1.069 | 9.4 | 1.110 | 14.4 | 159.5 | 1.149 | 18.7 | |||
1.029 | 4.1 | 1.070 | 9.5 | 99.4 | 1.111 | 14.5 | 1.150 | 18.8 | 222.1 | ||
1.030 | 4.2 | 42.4 | 1.071 | 9.6 | 1.112 | 14.6 | 1.151 | 19.0 | |||
1.031 | 4.4 | 1.072 | 9.7 | 1.113 | 14.7 | 1.152 | 19.1 | ||||
1.032 | 4.5 | 1.073 | 9.9 | 1.114 | 14.9 | 1.153 | 19.2 | ||||
1.033 | 4.7 | 1.074 | 10.0 | 1.115 | 15.0 | 1.154 | 19.3 | ||||
1.034 | 4.8 | 1.075 | 10.1 | 1.116 | 15.1 | 1.155 | 19.4 | ||||
1.035 | 4.9 | 1.076 | 10.2 | 1.117 | 15.2 | 1.156 | 19.5 | ||||
1.036 | 5.0 | 1.077 | 10.3 | 1.118 | 15.3 | 1.157 | 19.6 | ||||
1.037 | 5.1 | 1.078 | 10.5 | 1.119 | 15.4 | 1.158 | 19.7 | ||||
1.038 | 5.3 | 1.079 | 10.6 | 1.120 | 15.5 | 175.1 | 1.159 | 19.8 | |||
1.039 | 5.4 | 1.080 | 10.7 | 114.1 | 1.121 | 15.6 | 1.160 | 19.9 | 237.8 | ||
1.040 | 5.5 | 56.4 | 1.081 | 10.8 | 1.122 | 15.7 | 1.161 | 20.0 | |||
1.041 | 5.7 | 1.082 | 11.0 | 1.123 | 15.8 | 1.162 | 20.2 | ||||
1.042 | 5.8 | 1.083 | 11.1 | 1.124 | 15.9 | 1.163 | 20.3 | ||||
1.043 | 6.0 | 1.084 | 11.2 | 1.125 | 16.0 | 1.164 | 20.4 | ||||
1.044 | 6.1 | 1.085 | 11.3 | 1.126 | 16.2 | 1.165 | 20.5 | ||||
1.045 | 6.2 | 1.086 | 11.5 | 1.127 | 16.3 | 1.166 | 20.6 | ||||
1.046 | 6.4 | 1.087 | 11.6 | 1.128 | 16.4 | 1.167 | 20.7 | ||||
1.047 | 6.5 | 1.088 | 11.7 | 1.129 | 16.5 | 1.168 | 20.8 | ||||
1.048 | 6.7 | 1.089 | 11.8 | 1.130 | 16.6 | 190.6 | 1.169 | 20.9 | |||
1.049 | 6.8 | 1.090 | 11.9 | 128.6 | 1.131 | 16.7 | 1.170 | 21.0 | 253.7 | ||
1.050 | 6.9 | 70.6 | 1.091 | 12.0 | 1.132 | 16.8 | 1.171 | 21.1 | |||
1.051 | 7.0 | 1.092 | 12.1 | 1.133 | 16.9 | 1.172 | 21.2 | ||||
1.052 | 7.2 | 1.093 | 12.3 | 1.134 | 17.0 | 1.173 | 21.3 | ||||
1.053 | 7.3 | 1.094 | 12.4 | 1.135 | 17.1 | 1.174 | 21.4 | ||||
1.054 | 7.5 | 1.095 | 12.5 | 1.136 | 17.3 | 1.175 | 21.5 | ||||
1.055 | 7.6 | 1.096 | 12.6 | 1.137 | 17.4 | 1.176 | 21.6 | ||||
1.056 | 7.7 | 1.097 | 12.7 | 1.138 | 17.5 | 1.177 | 21.7 | ||||
1.057 | 7.9 | 1.098 | 12.8 | 1.139 | 17.6 | 1.178 | 21.8 | ||||
1.058 | 8.0 | 1.099 | 13.0 | 1.140 | 17.7 | 206.3 | |||||
1.059 | 8.1 | 1.100 | 13.1 | ||||||||
1.060 | 8.2 | 84.9 | 1.101 | 13.2 | 144.0 |
Temperatura (°C) | Intervalo de densidad (g/ml a 20 °C) | |||||||
de para | 1.00 | 1.05 | 1.10 | 1.15 | 1.20 | 1.25 | ||
1.05 | 1.10 | 1.15 | 1.20 | 1.25 | 1.30 | |||
10 | Sustraer la corrección de la densidad medida | .002 | .002 | .003 | .003 | .003 | .003 | |
11 | .002 | .002 | .003 | .003 | .003 | .003 | ||
12 | .001 | .002 | .002 | .003 | .003 | .002 | ||
13 | .001 | .002 | .002 | .003 | .002 | .002 | ||
14 | .001 | .001 | .002 | .002 | .002 | .002 | ||
15 | .001 | .001 | .002 | .002 | .002 | .002 | ||
16 | .001 | .001 | .001 | .002 | .002 | .001 | ||
17 | .001 | .001 | .001 | .001 | .001 | .001 | ||
18 | -- | .001 | .001 | .001 | .001 | .001 | ||
19 | -- | -- | .001 | .001 | -- | -- | ||
20 | -- | -- | -- | -- | -- | -- | ||
21 | -- | -- | .001 | .001 | .001 | -- | ||
22 | Sumar la corrección a la densidad medida | .001 | .001 | .001 | .001 | .001 | .001 | |
23 | .001 | .001 | .001 | .002 | .002 | .001 | ||
24 | .001 | .002 | .002 | .002 | .002 | .002 | ||
25 | .002 | .002 | .003 | .003 | .003 | .002 | ||
26 | .002 | .002 | .003 | .003 | .003 | .003 | ||
27 | .003 | .003 | .004 | .004 | .004 | .004 | ||
28 | .003 | .003 | .004 | .005 | .005 | .004 | ||
29 | .004 | .004 | .005 | .005 | .005 | .005 | ||
30 | .004 | .004 | .005 | .006 | .006 | .006 | ||
31 | .004 | .005 | .006 | .006 | .006 | .006 | ||
32 | .005 | .006 | .006 | .007 | .007 | .007 | ||
33 | .005 | .007 | .007 | .007 | .007 | .007 | ||
34 | .006 | .007 | .007 | .008 | .008 | .008 | ||
35 | .006 | .007 | .008 | .008 | .008 | .008 |