Table 5 Physical and chemical parameters of whey samples after electrical
discharge treatment
Whey type
Metal of conductive granules
and electrodes in the reaction
chamber
Treatment
duration, s
pH
Redox
potential,
(-) E, mV
sour milk
magnesium
30
4,31±0,21
56±2
60
4,75±0,23
73±3
120
5,18±0,20
195±8
manganese
30
4,59±0,20
79±2
60
5,07±0,21
102±3
120
5,25±0,24
219±8
cheese
magnesium
30
6,48±0,25
62±2
60
6,85±0,24
90±4
120
7,09±0,30
170±5
manganese
30
6,56±0,30
78±3
60
6,93±0,32
110±5
120
7,2±0,30
202±7
desalted
magnesium
30
5,45±0,25
45±2
60
5,54±0,20
85±3
120
5,87±0,21
176±7
manganese
30
5,51±0,20
60±3
60
5,80±0,2
120±5
120
5,93±0,20
180±5
Lower redox potential (increased antioxidant properties) has been detected in
treated whey. It is between -5 mV to -45...-219 mV depending on the treatment
duration. This probably indicates both the possible occurrence of Me↔Men+ +ne
process, as well as the complexation between magnesium ions and bio-ligands in whey.
The safety of treated whey has been proven by alternative in vitro method of
cytotoxicity studies using cellular test objects [6], which proves the possibility of using
it as raw material for everyday food products, namely bread products.
Further research focused on the possibility of using treated whey in bread product
technology. Thus test baking was carried out. The straight dough was prepared
according to wheat bread recipe (this bread was used as control). Sour milk whey and
whey enriched with Mg, Mn, and both Mg and Mn particles was introduced in the
amount of 15% to the mass of flour. The physical, chemical, and sensory parameters
of dough and bread as well as the complex quality index have been determined and
presented in Table 6 and Fig. 5 and 6.
It has been established that introduction of natural whey and whey separately
enriched with Mn and Mg particles increased the acidity of dough and bread. Whey
enriched with particles of both Mg and Mn did not increase those values compared to
control. It has been found that gas formation and dough specific volume increased and
its rheological properties have improved in all test samples, which led to increased
specific volume of bread. This parameter increased by 7.0% in bread with whey
- 1597 -