الفهرس 
AIM OF THE STUDYOnly 14 pages are availabe for public view
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Abstract
Yoghurt has been known since ancient times for its therapeutic and medical uses. It has been recently rediscovered it’s antibacterial, antitumor, and antioxidant properties by medical profession, particularly where conventional modern therapeutic agents are failing.
Yoghurt is adulterated by adding WPC. Or skimmed milk powder or adding water on the milk-base which yoghurt is made from. This yoghurt adulteration results not only in economic consequence but also affect public health.
This study aimed at providing a research into the chemical composition of yoghurt sold in Alexandria governorate and to establish the quality of the yoghurt available to a segment of the Egyptian population.
Materials and methods
Data collection:
A multistage random sample comprising of three brands of each balady and industrially processed (factory) yoghurt.
The ninety samples of each type of yoghurt were been purchased from different supermarkets and from three different commercial brands.
In this study, 360 yoghurt samples of four different types; Set plain full cream (balady), Set plain full cream (industrially processed), Set plain reduced cream (industrially processed), and Set flavored reduced cream (industrially processed) yoghurt, three brands from each type were collected from different markets of Alexandria six districts.
Ninety samples from each type are divided as follow five samples from each brand from Alexandria six districts (5×3×6=90 samples).
The present study consisted of two parts:
Part (1): Evaluation of the chemical quality of yoghurt The samples were prepared and analyzed in duplicate for acidity& ph, fat, protein, ash, total solid content, and calcium ratio. (42)
Part (2): Evaluation of the microbiological quality of yoghurt
This study revealed the following results:
1- There is a significant difference in the Moisture among different brands of balady yoghurt in Gomrok, Middle and Amria districts.
There was a significant difference in the moisture among factory yoghurt types (full cream, flavored half cream) among the brands D, E, F. It also shows that there was a significant difference in the moisture content of these brands among yoghurt types (full cream, flavored half cream),
2- There is a significant difference in the total solid among different brands of balady yoghurt in Gomrok, Middle and Amria districts, There is a significant difference in the total solid among both of factory yoghurt types (full cream & flavored) among in the brands D, E, F. It also shows that there is a significant difference in the total solid of these brands among yoghurt types (full cream, flavored half cream)
3- There was no a significant difference in ash content among different brands of balady yoghurt, there was a significant difference in ash among different yoghurt types (full cream. half cream. & flavored half cream.) In brand D, also there is a significant difference in full cream and flavored half cream. Types among different brands (D, E & F).
4- There is a significant difference in calcium mean among different brands of balady yoghurt in both west and Middle districts. There is a significant difference in calcium content among different factory yoghurt types (full cream. half cream. & flavored half cream.) In brand D, E& F, also there is a significant difference in full cream, half cream and flavored. half cream types among different brands (d, e & f).
5- There is a significant difference in protein content among different brands of balady yoghurt in Amria, Gomrok and Middle districts and there is a significant difference in protein content among different factory yoghurt types (full cream. half cream & flavored half cream.) In brand D, E & F.
6- There is a significant difference in the total fat content of brand C among different districts, and in both of Amria & Middle among the different three brands. There is a significant difference in the total fat mean among different brands of factory yoghurt types in two types- (full cream & flavored). It also shows that there is a significant difference in the total fat means of yoghurt types (full cream, flavored half cream) .in these three brands.
7- There is a significant difference in solid-not fat content among different brands of balady yoghurt in Amria, Gomrok and Middle districts. There was found no significant variation in solid-not fat content of different samples of industrially processed yoghurt because raw milk is standardized to a fixed solid-not fat content in order to ensure consistency of end product. But in case of balady yoghurt raw milk is used without subjecting to standardization. Hence more variation was observed in solid-not fat content of yoghurt.
8- There is no significant difference of Titratable acidity among balady yoghurt samples at all. But there is a significant difference in full cream type among different brands (D, E&F).
9- There is no significant difference in pH among balady yoghurt samples at al. there is a significant difference in full cream type among different brands (D, E & F).
10- There is a significant difference in total aerobic mesophilic plate count among different brands of balady yoghurt in both of Amria and Middle districts and no significant difference among factory yoghurt samples.
11- There is a significant difference in coliform count among different brands of balady yoghurt in both of Amria and Middle districts, and no significant difference among factory yoghurt samples.
12-There is a significant difference in mould & yeast count among different brands of balady yoghurt in Middle districts, and no significant difference among factory yoghurt samples.
13-There is no significant difference in fecal coliforms count among balady yoghurt & factory samples at al.
Recommendation
A- First- for yoghurt maker or sealer:
1- Using sterilized or pasteurized raw milk coming from healthy animals with no diseases or treated animals with antibiotics in manufacturing of yoghurt, to avoid harmful effects for consumer, and achieving good quality products.
2- Develop target yoghurt makers education program to improve yoghurt quality to be of highest quality, with proper moisture, fat, calcium, protein content, and also abundant culture for enough fermentation of raw milk lactose.
3- Increase control on market yoghurt distribution. Much more stringent inspection and more frequent collection of yoghurt samples from farm to markets are needed to detect and remove adulterated yoghurt samples.
4- Use yoghurt as healthy alternative to some medicine for abdominal troubles in many
B- Second- for yoghurt consumer:
1- Verifying from expiry date, use famous good brands with high quality, check the cans (containers) of yoghurt products before use, use the product in expiry period.
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