Fjölrit RALA - 22.03.1979, Síða 22

-16-
mineral content of whey, especially in regard to sodium
and phosphorus.
• A comparison of the mineral loss during production of
25% conc. whey at four different times is shown in
table 12 as well as the average values.
• According to the results in table 12, the mineral loss
varies depending on when the experiment was carried out.
The loss, however, never exceeds 14.6% of the original
amount of the minerals, i.e. the concentration of these
minerals always increases during this process.
• The average values in the last column of table 12 show
that the loss varies depending on the mineral in question.
The greatest loss is in Ca but the least in P. The losses
in Mg and K are slightly greater than that of P while the
loss in Na is closer to that of Ca.
• Figures 3-7 show how the mineral content changes in the
conc. whey and how much of the individual minerals is
lost during the production process. The figures are
drawn from the results of measurements carried out in
February but they still give a good idea of what happens,
i.e. the change is always in the same direction, although
the extent of the change may vary.
• Minerals are also lost when the conc. whey is centrifuged
or when A^ is made from A^.
• Figure 8 shows a flow diagram of the total flow occurring
on the column and-during centrifugation. It is possible
in this figure to observe how the quantity of dry matter,
protein and minerals in 1 1 of whey changes during the
production of 25% conc. whey used for mixing with fruit
juices.
Acid Measurements:
The acidity and acid amounts of A^, A^, A^, A^-A^^ and
filtrates from conc. wheys A^j-A^g were determined. The re-
sults are shown in table 13.
The acidity and acid amounts of whey seem to be quite
constant or from pH 4.04 to 4.10. The measurements