1.
Evaluation Of The Microbiological Quality Of Ice Cream Sold At Local Shops In Lahore
by Muhammad Bilal (2009-VA-492 | Dr. Naureen Naeem | Dr. Sana Ullah Iqbal | Prof. Dr. Aftab Ahmed Anjum.
Material type: ; Literary form:
not fiction
Publisher: 2016Dissertation note: Ice cream is a delicious, wholesome, nutritious frozen dairy food. It is noticed that generally manufacturing of ice cream on small scale production units like local shops doesn't totally follow the standard procedures of ice cream production. Ice cream can be contaminated with microorganisms if some ingredients have been added after pasteurization or by means of improper sanitation of the equipment and environment. Microbiological quality of ice cream reflects hygienic practice in production and is an indication of food safety. There was variation in quality of locally produced ice cream in different areas of Lahore.
Food safety is a scientific discipline describes handling, preparation and storage of food that prevents food borne diseases. It includes a number of ways that must be followed to avoid potentially severe health hazards. The tracks within this line of thought are safety between the market and consumer with the fast pace of life the consumption of fast food is going to increase day by day in Lahore. It is imperative to prepare food at good hygienic conditions because of its perishability. The usual thought is that food should be safe in the market and the concern is safe delivery and preparation of food for the consumer.
Microorganisms affecting food comes from natural microflora or are introduced by manufacturing steps ranging from processing storage and distribution. In some cases these micro flora have no effect on the food and can be consumed without consequence, but those that are introduced during course of processing depending on type and level of contamination can spoil the food and cause food borne illnesses.
Summary
49
Food can transmit diseases from one person to another as well as serve as growth medium for bacteria that can cause food poisoning. In the developed countries there are standards for food, whereas in less developed countries the main issue is the availability of safe water supply which is one of the critical item. Foodborne illness is a problem resulting from the consumption of contaminated food, bacteria, viruses, or parasites, natural toxins, chemicals that contaminate food.
For this study total 108 locally produced samples of ice cream were carried from different areas of Lahore. Mughalpura, Sadar, Model town, Gulberg, Town ship and Johar town. 6 shops from each area and 3 samples from each shop were purchased and put in the sampling box with ice packs. Samples were analyzes for microbial load in microbiology Lab of University of Veterinary and Animal Sciences.
Each sample was analyzed for microbiological analysis (Enumeration of Total Viable Count (TVC), Enumeration of Total Coliform Count (TCC), Enumeration of Total Staphylococcal Count (TSC) and detection of salmonella spp.
Nutrient agar was used to perform Total plate count, Mackonky agar was used for Total coliform count, Mannitol salt agar was used to count S.aureus , Salmonella Shigella agar for Salmonella detection . Each analysis was performed 3 times.
The samples collected from Mughalpura, Sadar and Model town were highly contaminated having more microbial count which shows contamination due to poor handling and hygienic conditions while Gulberg, Johar town and Town ship having less contaminated. Availability: Items available for loan: UVAS Library [Call number: 2543-T] (1).
2.
Comparative Quality Evaluation Of Raw And Pasteurized Milk
by Hafiza Saima Ghaffar (2009-VA-230) | Dr. Imran Altaf | Prof. Dr. Aftab Ahmed Anjum | Dr. Sana Ullah Iqbal.
Material type: ; Literary form:
not fiction
Publisher: 2016Dissertation note: This particular project was designed to evaluate the overall quality of raw and pasteurized milk available at different areas of Lahore. The parameter which was checked includes microbiological analysis, adulterants, physicochemical properties and the effect of temperature on vitamin C in milk samples. Raw samples were collected from ten different towns of Lahore, whereas pasteurized milk samples belong to ten different brands. Ten samples were collected under control conditions from animals in sterilized containers.
For microbiological analysis four parameters were selected including total plate count (TPC), total coliform count (TCC), total psychrotrophic count (TPSC) and total yeast and mold count (TYMC) whereas, different adulterants like adulteration test was done such as urea, starch, hydrogen peroxide, detergent or soap, sorbitol, quaternary ammonium compound, boric acid, cane sugar, sodium chloride, formalin and hypochlorite were checked by using the milk adulteration kit in QOL. Milk contains casein and whey proteins. Whey protein being added in the milk to increase its density which is considers being an adulterant. In this project whey protein was estimated in all milk samples by titration method. Physicochemical characteristics of milk are an important parameter to judge the quality of milk. These physicochemical properties include fat%, SNF%, density kg/m3, lactose%, solid/ash, protein% and pH. Physicochemical properties were evaluated mechanically by Milkoscan. Heat treatment is an important method to reduce the microbiological contamination of milk. These treatments may include pasteurization and UHT etc. During the heat treatment some of the micronutrients may deteriorate thus compromising the quality of milk. Vitamin C is among those heat labile micronutrients. Vitamin C was checked quantitatively in market and self-collected samples by using titration method.
It was concluded that total plate count TPC, TCC, TPSC and TYMC of raw milk samples were above the standard value indicating the poor quality of the milk. As far as the pasteurized milk samples were concerned ninety percent of the samples showing higher values for TCC, TPSC and TYMC. Total plate counts of all self-collected raw milk from a healthy animal were found within the standard value. Counts were in range of 3.8x 103 – 8.9x103 CFU/mL of all milk samples. TPC of all self-collected raw milk from a healthy animal were found within the standard TCC were found within permissible value (102 CFU/mL .TPSC were negative for all milk samples. TYMC were in range of 2.6x101 -7.2x101 CFU/mL. Among milk samples (n=10), three samples (30%) were positive for TYMC were while remaining samples (70%) were negative and showed no growth.
Physicochemical factor show that 50 percent of raw milk have low nutritional value as compared to the standards which are buffalo and cow milk contains 7.6, 4.5% fat, 3.8, 3.8 % protein, 5.1, 4.9% lactose, 0.78, 0.72% ash and 17.0, 13.9% total solid respectively. In raw milk mean of fat (%), solid not fat (%), lactose (%), Solid/ash (0%), protein(%) and pH were 4.50±0.03, 7.915±0.06, 23.05±0.055, 3.893±0.06, 3.85±0.05, and6.9±0.0.02 respectively. In pasteurized milk mean value for fat, SNF, lactose, ash, protein and pH were 3.48 ±0.13, 7.24±0.10, 3.60±0.05,0.5 ±0.06, 2.82±0.05, 7.2±0.20 respectively. Pasteurized milk is good for consumption.
Different adulterant such as urea, starch, hydrogen peroxide, Sorbitol, QAC, Boric acid, Cane sugar, NaCl, Carbonate, Formalin, hypochlorite, whey protein, Added water and soap /detergents were evaluated in all milk samples. Among these adulterant water (66%) was found in majority of milk samples, followed by whey protein (15%), starch (13%), (10%) NaCl and
(8%) cane sugar were detected in raw milk samples. n Pasteurized milk samples only added water (49%) and whey protein (31%) was detected.
Among the raw milk samples the maximum and minimum concentration of vitamin C was observed 0.33±0.02 and 3.33 ±0.02 mg/100ml and for pasteurized milk maximum and minimum concentration of vitamin C was observed 2.54mg/100ml and 0.32 ±0.02 mg/100ml respectively. In self- collected samples the minimum and maximum concentration of vitamin C was observed 5.25±0.02 and 8.34 ±0.04 mg/100ml respectively and after pasteurization in laboratory minimum and maximum concentration of vitamin C was observed 3.48±0.04 and 5.83 ±0.02 mg/100ml respectively. These observations had showed that pasteurization treatment decreased Vitamin C quantity. Availability: Items available for loan: UVAS Library [Call number: 2536-T] (1).
