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Research Article
Microbiological Quality of Ice Cream Sold in Gilgit Town

Khalil Ahmed, Azhar Hussain, Imran , Mudassier Ali Qazalbash and Wajid Hussain
Ice cream is a food commonly consumed during summer. It harbors many potent pathogens, its microbial quality especially bacteriological quality has always been crucially important to public health. This study aims to access bacteriological quality of ice cream sold in different areas of Gilgit town. Randomly collected ice cream samples were studied to determine the microbiological load or colony forming units per gram (CFU/g) using the standard aerobic plate count method. All samples showed positive growth of bacteria ranging from 2.2 X 103 to 8-2 X 104 CFU/g. Seven bacterial species were isolated. The highest frequency of isolation was Escherichia coli 20 (100%) and least isolation was Salmonella spp. 3 (15%). For confirmation the colonies were tested biochemically and were identified up to specie level.
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  How to cite this article:

Khalil Ahmed, Azhar Hussain, Imran , Mudassier Ali Qazalbash and Wajid Hussain, 2009. Microbiological Quality of Ice Cream Sold in Gilgit Town. Pakistan Journal of Nutrition, 8: 1397-1400.

DOI: 10.3923/pjn.2009.1397.1400



Ice cream is a nutritionally enriched congealed dairy product consumed by all age groups particularly children, during summer (Sharif et al., 2005). The ingredients of Ice cream may be various combinations of milk, cream, evaporated or condensed milk, dried milk, colouring material, flavors, fruits, nuts, sweetening agents, eggs and eggs products stabilizer. Any of these may account for the various specific species of bacteria (Yaman et al., 2006).

Ice cream is a nutritious food for human and also an excellent medium for the growth of many microorganisms some of which may cause diseases in human beings e.g. Cholera, typhoid, bacillary dysentery.

Contaminated ice cream causes several outbreaks of gastrointestinal diseases in a number of countries in Asia, Europe and North America (Dijuretic et al., 1997; Dijuretic and Wall, 1996; Chug, 1997).

In England and Wales two outbreaks of S. enteritidis phage type 4 infections were reported in 1990 and 1995 due to consumption of ice cream (Hennessy et al., 1996).

Quality of ice cream depends on extrinsic factors that include manufacture procedure, as well as intrinsic factors that include the proportion of ingredients used. Primary sources of microbial contamination of ice cream include water and raw milk, whereas secondary sources include flavoring agents, utensils and handling.

Possible sources of these microorganisms in ice cream have been reported to include raw materials used for the composition of ice cream-mix, such as milk and milk powder, cream, flavouring and colouring substances and sanitizer (Verma, 1972; Bathla and Rao, 1973) and from contaminate air during processing (Gomez, 1969).

In Gilgit town ice cream is manufactured on small scale by using the dried and raw milk and sale in the city at retail outlets.

The aim of this study was to determine the bacteriological quality of commercially soled ice creams in Gilgit town and their potential risk to public health.


Collection of samples: Twenty ice cream samples (cups) were randomly collected from eight different areas/location of Gilgit town (Fig. 1). The collected samples were immediately shifted to the laboratory of Department of Biological Sciences, Karakoram International University, Gilgit in a cold box.

Microbiological analysis: Serial dilutions: In serial dilutions 1 gram of ice cream was aseptically transferred into 9 ml of distilled water and homogenized by vertex. Subsequent serial dilutions were made up to 105.

Culture of samples: For aerobic enumeration of colonies 1 ml sample was cultured on Nutrient agar (Oxoid) and incubated at 37oC for 24 h. The following day the total number of colonies were counted and read morphology, for their identification. Separated colonies were sub culture on freshly prepared Nutrient agar, MacConkey (Oxoid) and Salmonella Shigella agar (Oxoid) plates. Further identification of the Gram negative colonies was performed by biochemical tests such as production of urease, utilization of sugars, carbon and production of indole, H2S gas, oxidase and on the basis of motility of the bacteria (WHO Manual, 1987) and the gram positive bacteria colonies were identified by coagulase and catalase tests.


The total viable counts in samples of the eight locations of Gilgit town are presented in Table 1. The samples of all the areas show heavy contamination of bacteria ranging from > 2.2x103 CFU/g to 6.8x104 CFU/g. The mean results indicate that the highest contamination was found in Punial Road ice cream samples 6.6x104 CFU/g followed by Park Hotel link Road 3.6x104 CFU/g, Nasim Cinema Bazaar 2.5x104 CFU/g, Hospital Road 8.5x103 CFU/g, Jamat Khana Bazar 7.7x103, Yadgar chowk 4.5x103 CFU/g, Shaheed Milat road 3.4x103 CFU/g and Khazana Road ice cream samples had 2.4x103 CFU/g.

Fig. 1:

Site collection area of Ice cream samples in Gilgit city

Table 2 show the occurrence of different bacteria in the investigated ice cream samples. Escherichia coli is the commonest organism and was isolated from all the samples of all the areas, Klebsiella sp. was isolated from 17 samples except sample numbers PRIS2’ PRIS3 of Punial road and sample no. NCBIS1 of Nasim Cinema Bazar. Overall isolation of Proteus was from 09 samples i.e. in all the samples of hospital road, in one sample of each of Punial road, Khazana road, Jamat khana Bazar, Park hotel link road Yadgar Chowk and Shaheed Millat road. Bacillus sp. were isolated from 4 samples, i.e. in one sample each of Punial road, Khazana road, Jamat Khana Bazar and yadgar chowk. Salmonella was isolated from 3 sample i.e. one each from Punial road, Nasim Cinema road and Park hotel link road. Staphylococcus sp. was in 10 samples i.e. in two samples of Punial road, one sample each of Hospital road and Park hotel link road, in 02 samples each of Jamat Khana bazar, Nasim Cinema bazar.

Table 3 shows incidence of different bacteria isolated during the investigation.

The infestation ratio were: Escherichia coli 20 (20) 100%, Klebsiella sp. 17 (20) 85%, Proteus 9 (20) 45%, Bacillus sp. 04 (20) 20%, Salmonella 03 (20) 15%, Staphylococcus sp. 10 (20) 50%.

Table 1:

Total Viable count (CFU/g) of various bacteria isolated from ice cream samples


The results obtained in this study represent the current status of microbiological quality of ice cream being sold in Gilgit town. All the analyzed ice cream samples (n = 20) showed heavy contamination of notable bacteria (E. coli, Klebsiella, Proteus, Salmonella and Staphylococcus) which indicates fecal contamination. The presence of this high level of fecal coliforms contamination represents a public health risk due to the possible presence and transmission of pathogens such as enteropathogenic Escherichia coli, Hepatitis A virus, poliomyelitis virus, while Entamoeba histolytica may also be present in the ice cream (Arias and Windrantz, 2000). The mode of transmission of all these bacteria is fecal-oral route and or via common house flies.

The results suggest negligence such as poor sanitation during the preparation and/or storage of these products. These include the observed dirty premises and utensils used, the use of bare hands in preparing the products (personal communication with the handlers).

In this study three most important genera Escherichia coli, Salmonella sp. and Staphylococcus sp. were also isolated. Escherichia coli strains EPEC, ETEC, EHEC and invasive strains are pathogenic to children of <5 years. Salmonella is still the most important acute agent causing food bone diseases (Tood, 1997). Consumption of ice cream contaminated with enteropathogenic bacteria such as Salmonella has been the cause of several outbreaks (Hennessy et al., 1996). In the Northern Areas of Pakistan Gilgit Ahmed et al. (2005) isolated twenty one Salmonella typhi from 585 suspected gastroenteritis patients. Staphylococcus, which is commonly Staphylococcus aureus when transmitted from man and animal, can lead to staphylococcal food poisoning as a result of growth of the organism and release of enterotoxin into the food.

Table 2:

Bacterial Species isolated from different ice cream samples from areas

Table 3:

Incidence and percentage infestation of bacteria isolated from Ice cream

Entrotoxin production and secretion occurs especially when ice cream products are not hygienically prepared and stored. The presence of starch and protein encourage enterotoxin production by the microorganisms (Wistreich and Lechtman, 1980). The possible source (s) of this organism in ice cream could be from human nose where it is commonly found; hands, skin and clothing of handlers (Hobbs and Golbert, 1982). Coughing, talking and sneezing produce droplets, which could settle on, ice cream during transportation In Gilgit most of the population produce homemade ice cream for domestic use as well as commercial purposes by using the ingredients dry milk, sugar and water.

The presence of fecal coliform indicates post-treatment contamination which may either come from water, lack of personal hygiene of the ice cream manufacturer, utensils used for ice cream and distribution environment. A study conducted by Ahmed and Shakoori (2002) reported 640-683 E. coli colonies /100 of drinking water. The ice cream manufacturers use the same water for the preparation of ice cream as well as for washing of their hands and utensils. Once the ice cream become contaminated, freezing temperature later could not make the product safer (Jay, 1996).

Ahmed, K. and A.R. Shakoori, 2002. Vibrio cholerae El Tor, Ogawa 01 as the main etiological agent of the two major outbreaks of gastroenteritis in the Northern areas of Pakistan, Gilgit. Pak. J. Zool., 34: 73-80.

Ahmed, K., R.S. Farah and A.R. Shakoori, 2005. Etiology of salmonellosis in the Northern Areas of Pakistan. Journal of Health and Population in Developing Countries, pp: 13.

Arias, M.L. and P. Windrantz, 2000. Evaluation of the bacteriological quality of ice cream sold at San Jose, Costa Rica. Arch. Latinoam. Nutr., 50: 301-303.
Direct Link  |  

Ay, J.M., 1996. Modern Food Microbiology, 4th Edn., Champman and Hall Inc., New York.

Bathla, J.M. and Y.S. Rao., 1973. Microbial quality of ingredients in relation to that of Ice cream. J. Res. Sci., 22: 59-66.

Chug., A., 1997. Salmonella outbreak from ice cream. Indian Pediatr., 1: 976-977.

Dijuretic, T. and P.G. Wall, 1996. An outbreak of Salmonella infection from ice cream. N. Engl. J. Med., 1: 335-824.

Dijuretic, T., P.G. Wall and G. Nichols, 1997. General outbreaks of infectious intestinal diseases associated with milk and dairy products in England and Wales 1992-1996. Commun. Dis. Rep., 7: 41-45.

El-Sharef, N., K.S. Ghenghesh, Y.S. Abognah, S.O. Gnan and A. Rahouma, 2006. Bacteriological quality of ice cream in Tripoli-Libya. Food Control, 17: 637-641.
CrossRef  |  Direct Link  |  

Gomez, A., 1969. Microbial content and hygienic conditions of ice cream sold in Leon Alimentaria. 6: 21-25.

Hennessy, T.W., C.W. Hedberg, L. Slutsker, K.W. White and M.S. Besser-wiek et al., 1996. A national outbreak of Salmonella enteritidis infections from ice cream. N. Engl. J. Med., 334: 1281-1286.

Hobbs, B.C. and J.R. Golbert, 1982. Food Poisoning and Food Hygiene. 4th Edn., Edward Arnold Limited, London, pp: 366.

Tood, E.C., 1997. Epidemiology of foodborne diseases. World Health Stat. Q., 50: 30-50.

Verma, G.S., 1972. Bacteria quality of some ingredients used in the manufacture of ice cream. Ind. J. Anim. Res., 6: 27-30.

World Health Organization, 1987. Manual for laboratory investigations of acute enteric infections. Programme for Control of Diarrhoeal Diseases.

Yaman, H., M. Elmali, Z. Ulukanli, M. Tuzcu and K. Genctav, 2006. Microbial quality of ice cream sold openly by retail outlets in Turkey. Rev. Med. Vet., 157: 457-462.
Direct Link  |  

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