Fjölrit RALA - 22.03.1979, Blaðsíða 18

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erated. One cylinder containing was not heated in order
to see the possible effects of heating on precipitation.
• The mixtures which were centrifuged were filtered
through Whatman no. 1 filter paper into graduated cyl-
inders, heated for 2 minutes and refrigerated. For a
comparison, these same mixtures were placed directly into
cylinders, heated for 2 minutes and then refrigerated. It
was inspected daily whether precipitation had occurred.
D. RESULTS
1. Sensory Evaluation
(1) Fifteen out of 20 participants regarded Ag (25%
concentrated whey) as the best. Twelve said that Ag (35%
concentrated whey) was second best. Fourteen regarded A^
(75% concentrated whey) as being the worst and A,. (10% con-
centrated whey) as second worst. It was decided that 25%
concentrated whey be used in the future for mixing.
(2) Better beverages are obtained by using pure fruit
juices rather than essences. It was decided to use juices
in the future for mixing with the concentrated whey.
(3) The flavor of the beverages changes during packag-
ing which shows that the heat treatment affects the flavor.
It is therefore necessary to use a lower temperature for a
longer period of time when pasteurizing. It is also poss-
ible, however, that the homogenizer had shredded the fruit
fibers too much which resulted in a change in flavor. The
fruit flavor of D^ was not as distinct as that of D^. Bev-
erages stored at room temperature became off-flavored on
storage, in spite of their being G-products which receive
a special heat treatment.
Dg+ (70% concentrated whey, 15% orange juice and 15% pine-
apple juice) was used from now on for comparison when test-
ing other fruit and berry juices.
(4) Mixing grape and tomato juices with concentrated
whey gave good results but apple and pear juices gave poor
results.