الفهرس 
IntrductionOnly 14 pages are availabe for public view
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Abstract
Fermented dairy products have a positive health outlook over the past years .
Frozen yoghurt has become a common product especially after the addition of
some natural fruits and vegetables to produce a high quality FY and the acceptable
chemical, functional and sensory qualities . Using of carrot puree solids, carrots
with orange juice solids or persimmon pulp solids as a fat replacer, an alternative
milk fat, a source of dietary fiber and natural antioxidants. Previous studies refer to
the importance of adding such natural sources to food in general and dairy products
in particular to increase their functional properties of these products. Therefore,
this study aims to produce of functional frozen yoghurt with new and suitable
flavour for Egyptian taste and provide many functional properties with high quality
and reasonable price.
Carrots, orange and persimmon were selected as means of replacing
different percentages of fat in the FY to reach the best sensory, chemical and
rheological properties. This is in addition to produce a product acquired functional
properties and healthy benefits.
The study is divided into three parts as follows:
Part 1 Influence of addition carrot puree solids (CPS) to frozen yoghurt on some
physical, rheological, bacteriological and organoleptic properties
Five treatments were done as follows:
1- T1
: Full fat (4% fat) frozen yoghurt (FY) without CPS (control1
).
2- T2
: Treatment with 3% fat FY with adding 1% CPS.
3- T3
: Treatment with 2% fat FY with adding 2% CPS.
4- T4
: Treatment with 1% fat FY with adding 3% CPS.
Summary
152
5- T5
: Treatment with 1% fat FY without adding CPS (control2
).
The results obtained can be summarized as follows:
1- Specific gravity and weight per gallon of FY significantly (p≤0.05) higher for
CPS treatments than full fat or low fat control (T
1 and T5
) treatments.
2- The reduction in the freezing point degree increased significantly (p≤0.05) with
the increase of CPS added ratios to FY treatments.
3- The apparent viscosity of CFY increased significantly (p≤0.05) in parallel with
the added ratios of CPS. T4
treatment had higher apparent viscosity than other
treatments.
4- The total viable LAB decreased significantly (p≤0.05) with the addition of CPS
after aging compared with control treatments (T1 and T5
).
5- Specific gravity and weight per gallon of CFY significantly (p≤0.05) increased
with added CPS compared with control (T1 and T5
) treatments.
6- Overrun % of CFY increased significantly (p≤0.05) in parallel the with added
CPS compared with T5
treatment. T1
treatment had the highest overrun %.
7- The melting rate % of CFY made with addition of different ratios of CPS
decreased significantly (p≤0.05) during 60 min compared with controls (T1
and
T5
) treatments. T4 treatment recorded a lowe st melting rate followed by T3
and
then T
2
.
8- Color measurement: L* value: White colour, a*: Green and red colour and b*:
Yellow and blue colour..