email   Email Us: info@lupinepublishers.com phone   Call Us: +1 (914) 407-6109   57 West 57th Street, 3rd floor, New York - NY 10019, USA

Lupine Publishers Group

Lupine Publishers

lupinepublishers

ISSN: 2637-4749

Concepts of Dairy & Veterinary Sciences

Research Article(ISSN: 2637-4749)

Evaluation of Milk Quality Vended at Nosharoferoz City of Sindh, Pakistan Volume 2 - Issue 4

Ghulam Shabir Barham1*, Muhammad Haroon Baloch2, Atta Hussain Shah1, Gul Bahar Khaskheli1, Shoaib Ahmed Pirzado3, Mansoor Tariq4 and Asad Ali Khaskheli3

  • 1Department of Animal Products Technology, Sindh Agriculture University, Tandojam, Pakistan
  • 2Department of Livestock Management, Sindh Agriculture University, Tandojam, Pakistan
  • 3Department of Animal Nutrition, Sindh Agriculture University, Tandojam, Pakistan
  • 4Department of Veterinary Pathology, Sindh Agriculture University, Tandojam, Pakistan

Received: March 22, 2019;   Published: April 17, 2019

Corresponding author: Dr. Ghulam Shabir Barham, Department of Animal Products Technology, Faculty of Animal Husbandry & Veterinary Sciences, Sindh Agriculture University, Tandojam, Pakistan

DOI: 10.32474/CDVS.2019.02.000144

Abstract PDF

Abstract

Current study was designed to assess the quality of milk vended by different intermediaries at the surrounding of Nosharoferoz city during the year 2016-17. A total of 100 milk samples were collected each of twenty (n=20) from dairy farms, milk collectors, milk venders, processors and retailers brought in the Department of Animal Products Technology, Faculty of Animal Husbandry and Veterinary Sciences, Sindh Agriculture University Tandojam for analysis. Among all the detected adulterants in market milk, water was at the top followed by detergent, rice flour, starch, cane sugar, formalin, caustic soda, salt, urea, H2O2, glucose, arrowroot, SMP, vegetable oil and dalda ghee. The extent of extraneous water in milk sold by retailers, milk venders and milk collectors were found significantly (P˂0.05) high compared to processors and dairy farms. Noteworthy increase was observed in pH value and the freezing point stirred towards water in milk vended by retailer, milk venders and milk collectors, while the specific gravity of milk obtained by dairy farms and processors was noticed comparatively (P<0.05) high. The fat, protein, lactose and ash contents of milk samples were found comparatively (P<0.05) low at retailer, milk vender and milk collector level than processor and dairy farm.

Keywords: Market milk; Extraneous water; Physico-chemical quality; Nosharoferoz; Sindh; Pakistan

Introduction

Milk is the best and cheapest source of nutrition and an article of daily diet, easily accepted and used by all the age groups in rural as well as in urban areas. Milk, if present in its natural form, has high food value and supplies good quality nutrients like energy providing lactose and fat, body building proteins, the bone forming calcium, health promoting vitamins and minerals in significant amount than any other single food [1]. Historical evidence indicates that the nations which used to obtain highest calories from milk and milk products were more civilized and capable of having sound administration and such societies enjoy almost complete freedom from nutritional disease. In contrast, the poorly or underdeveloped areas of the world have a primitive or non-existent milk supply and have numerous inhabitants suffering from nutritional deficiency, especially infants and children [2]. No doubt, milk is a perishable commodity and is likely to be spoiled during summer season when weather becomes very hot [3]. Unfortunately, due to unorganized and non-regulated marketing systems, the quality of milk is hardly maintained at consumer level [4]. In order to keep milk temporarily fresh, some unethical activities are usually adapted to prevent the financial losses due to the spoilage of milk during its transportation and sale [5]. It has been observed that adulteration of milk is one of the most serious issues that the dairy sector of Pakistan is today facing, causing not only major economic losses for the processing industry, but also a major health risk for the consumers. Due to the spread of small holding farmers and consequent supply chain complexities, milk handling processes in the traditional system are extremely unhygienic and there is no enforcement of standards, so the result is poor quality products. In order to keep milk temporarily fresh, middlemen commonly add ice to the milk, which results in dilution of milk solids. Compounding the problem, middlemen attempt to counter the dilution by adding vegetable oil, starch, flour, sugarcane, whey powder, skim milk powder, and other ingredients to extend the solid content of the milk [6]. Besides, some adulterants like detergent are used to enhance the cosmetic nature of milk. When water is added in milk, its foamy appearance diminishes, so to give milk a foamy appearance artificially detergents are added in it. Hair removing powders (calcium thioglycolate/ potassium thioglycolate/calcium salts of thioglycolic acid) and urea are added for whitening of milk and giving it genuine look. Only few grams of urea are enough to bring milk in its original state [7]. The adulteration of milk may cause significant problems for human health for example; the milk adulterated with contaminated water is a serious health hazard because of potential waterborne diseases. Other adulterants like detergents, urea, starch, caustic soda, formalin, hydrogen peroxide and other synthetic components may cause impairments, food poisoning, gastroenteritis, vomiting, nausea, renal failure, liver damage, heart problems, cancer or even death in all age groups [8,9]. Feeling gravity of problem, study has been designed, to evaluate the hygienic and physicochemical quality of milk vended by various milk intermediaries at Nosharoferoz city of Sindh, Pakistan.

Materials and Methods

Collection of Milk Samples

A total of 100 unprocessed market milk samples were collected from different milk intermediaries; dairy farms, milk collectors, milk venders, processors and retailers from the locality of Nosharoferoz city of Sindh province of Pakistan for the evaluation of hygienic and physico-chemical quality of milk.

Assessment of Hygienic Quality

For the evaluation of hygienic quality all the collected milk samples were screened for the various adulterants as per standard procedure as reported by Tipu [3] and Khaskheli [10] and the standard procedure for screening of adulterants was mentioned in Figure 1.

Figure 1: Standard milk adulteration testing kit method.

Lupinepublishers-openaccess-Dairy-Veterinaryscience

Presence of Extraneous Water

The presence of extraneous water in market milk was detected from depression of freezing point through Cryoscope as reported by Association of Official Analytical Chemists [11]. The value of freezing point of market milk greater than the values of freezing point of control was assumed as presence of extraneous water in market.

Extent of Extraneous Water in Market Milk

Extent of extraneous water in market milk was observed from the depression of freezing point (through Cryoscope) and calculated by subtracting the observed freezing point of market milk from that of freezing point of base (control) and thereafter by dividing it with freezing point of base using following formula [11].

Physico-Chemical Analysis

pH value

The pH value of market milk samples was recorded by using pH meter according to the method of AOAC [11]. The milk sample was taken in to a beaker, electrodes along with temperature probe was inserted to sample. The constant reading appeared on pH meter base was noted and recorded as pH value of milk sample.

Titratable acidity

The Titratable acidity of spiked milk samples was determined according to the method of AOAC [11]. Milk sample (9ml) with phenolphthalein (3drops) was titrated using N/10 (0.01N) NaOH solution till appearance of light pink colour. The volume of N/10 NaOH solution used in the titration was noted. Thereafter following formula was applied to calculate the acidity percent in milk samples.

Freezing Point

Freezing point of market milk samples was determined according to the method of AOAC [11] by using Cryoscopy technique. Milk sample was loaded on the Cryoscope. The constant reading appeared on the screen of Cryoscope was noted and recorded as freezing point of milk.

Specific Gravity

Specific gravity of market milk samples was determined according to the method of Association of Official Analytical Chemists [11] using pycnometer. The density of milk was measured against the density of standard (water). The pre-weighed pycnometer was filled with standard reference fluid (water) to some pre-determined level at 20oC and weight was taken. Similarly, pre- prepared milk sample was filled in pycnometer at similar level and temperature and weighed. Specific gravity of milk was calculated by the following formula:

Fat Content

Fat content of market milk samples was determined by Gerber method as described by James [12]. Milk sample (11ml) was mixed with 90% sulfuric acid (10ml) and amyl alcohol (1ml) in butyrometer and closed with rubber cork. The butyrometer was placed in a Gerber centrifuge machine and centrifuged for 5 min. at 1100 round per minute (r.p.m). The butyrometer was transferred to water bath at 65°C to make fat prominent on butyrometer scale. The fat percentage was noted on the butyrometer scale.

Protein Content

Protein content of market milk samples was determined according to the method of British Standards Institution [13]. The milk sample (5g) was digested using Micro-Kjeldhal digester in the presence of catalyst (0.2g copper sulfate and 2.0g sodium sulfate) where sulfuric acid (30ml) was used as an oxidizing agent. The digested sample was diluted with distilled water (250ml). Then 5ml portion from the diluted sample was distilled with 40% NaOH using Micro-Kjeldhal distillation unit where steam was distilled over 2% boric acid (5ml) containing an indicator (Bromocresol green) for 3 minutes. The ammonia trapped in boric acid was determined by titrating with 0.1N HCl. The nitrogen percentage was calculated using the following formula:

Lactose content

Lactose content of market milk samples was determined by subtracting the sum of total percent of fat, protein ash content from that of TS content of milk as reported by James [12]. Lactose content of market milk samples were calculated by using following formula:

Ash Content

Ash content of market milk samples was determined by Gravimetric method as described by AOAC [11] using muffle furnace. The milk sample (5g) was taken in pre-weighed crucible and transferred to muffle furnace (550°C) for 4±1 h. Ignited sample was transferred to desiccator having silica gel as desiccant. After 1h the dish was weighed, and the content was calculated by following formula:

Statistical Analysis

The data were analyzed through computerized statistical package i.e. Student Edition of Statistix (SXW), Version 8.1 (Copyright 2005, Analytical Software, USA). The data so obtained was tabulated and analyzed through statistical procedure of summary statistics, under which Descriptive statistics was applied to observe the variability in the data. The data was further analyzed through statistical procedure of analysis of variance (ANOVA) to observe the significant differences among the variables and in case of the significant differences exist; the means were further computed using least significant difference (LSD) at 5% level of probability.

Result

Assessment of Hygienic Quality

In the current investigation all the collected market milk (n=100) samples from dairy farms, milk collectors, milk venders, processors and retailers were screened for different adulterants to check the hygienic quality of market milk. The water (56%) was most common adulterant found in all the market milk samples followed by detergent (20%), rice flour (17%), each of starch and cane sugar (16%), formalin (15%), caustic soda (13%), salt (11%), each of urea and hydrogen peroxide (9%), glucose (8%), each of arrowroot and skimmed milk powder (7%) vegetable oil (6%) and dalda (4%) respectively were found during present study (Figure 2).

Legends: H2O2 = Hydrogen peroxide and SMP = Skimmed milk powder

Figure 2: Positive percentage of various adulterants in market milk vended at Nosharoferoz city of Sindh, Pakistan.

Lupinepublishers-openaccess-Dairy-Veterinaryscience

Extent of Extraneous Water in Market Milk Samples

The extent of extraneous water of milk sold by different milk intermediaries at Nosharoferoz district of Sindh, Pakistan was detected from the depression of freezing point. Among all milk intermediaries the considerably (P˂0.05) higher extent of extraneous water was noted at retailer (42.21±4.163%), milk vender (33.52±4.833%) and milk collector (31.80±4.430%) level compared to that of processor (12.07±3.993%) and dairy farm (7.62±3.165%) level (Figure 3).

LSD (0.05)= 11.663

SE±= 5.8751

Figure 3: Extent of extraneous water in market milk sold by different intermediaries at Nosharoferoz, Sindh, Pakistan.

Lupinepublishers-openaccess-Dairy-Veterinaryscience

Physico-Chemical Analysis

For the evaluation of physical quality of market milk sold at Nosharoferoz city of Sindh Pakistan; pH value, titratable acidity, freezing point and specific gravity of all hundred (100) of milk samples were analyzed and results are presented in Table 1. The pH value of milk collected from retailer (6.96) was found comparatively (P<0.05) higher than that of processor, milk vender, milk collector and dairy farm (6.87, 6.83, 6.79 and 6.75, respectively), whereas the titratable acidity was recorded high at dairy farm (0.16%) and milk collector (0.15%) compared to milk vender, processor and retailer (0.13,011 and 0.11%), respectively. The freezing point of milk vended at dairy farms (-0.501°C) was found comparatively (P<0.05) low, while the specific gravity was recorded high (1.0291) against milk vended by processors (-0.476°C and 1.0275), milk collectors (-0.370°C and 1.0251), milk venders (-0.356°C and 1.0232) and retailers (-0.313°C and 1.0201), respectively. The fat, protein, lactose and ash contents of milk samples collected from dairy farms (4.43, 3.99, 3.88 and 0.76%, respectively) were found significantly (P<0.05) high, followed by processors (4.31, 3.72, 3.90 and 0.74%, respectively), milk collectors (3.56, 3.64, 3.57 and 0.68%, respectively) and milk venders (3.42, 3.58, 3.60 and 0.63%, respectively), while, the lowest content of fat, protein, lactose and ash was recorded at retailer (2.87, 311, 3.43 and 0.51%, respectively) level (Table 2).

Table 1: Physical quality attributes of market milk vended by various intermediaries at Nosharoferoz city of Sindh, Pakistan.

Lupinepublishers-openaccess-Dairy-Veterinaryscience

Means with different letters in same row varied significantly from one another.

Table 2: Physical quality attributes of market milk vended by various intermediaries at Nosharoferoz city of Sindh, Pakistan.

Lupinepublishers-openaccess-Dairy-Veterinaryscience

Means with different letters in same row varied significantly from one another

Discussion

Milk adulteration is the one of the burning issues of the country, due to unhygienic milk supply nation is derived from good quality nutrients [14]. During current investigation a wide range of adulterants; water, detergent, rice flour, starch, cane sugar, formalin, caustic soda, salt, urea, hydrogen peroxide, glucose, arrowroot, skimmed milk powder, vegetable oil and dalda were detected. In support with present findings, many scientists around the world reported that the milk intermediaries especially gawalas/dhodis are used to adulterate the milk with various adulterants, which pose health risks for consumers only for their little financial interest [15-18]. The findings of current research and studies carried out by other researchers suggested that, mainly the extent of extraneous water in market milk vended by retailer, milk vender and collector was comparatively high than the milk of dairy farms [19-21]. These dealers adulterated the milk to increase their profit and try to fulfill the gap between demand and supply [22].

Physico-Chemical Quality of Market Milk

It was confirmed from current investigation and findings of Javaid and Memon that the addition of water and other adulterants in milk affect the pH value and titratable acidity of milk collected from direct seller, milk collection center and that of dairy farm milk [4,23]. In favour of present results other authors reported that due to presence of extraneous water freezing point of milk vended by retailer, milk venders and milk collectors was adversely affected and noted to be high, while specific gravity was low compared to milk of dairy farm and processor [24]. Similar like physical quality of milk vended by retailer, milk venders and milk collector the nutritive parameters; fat, protein, lactose and ash contents were also drastically decreased with the addition of water and other inferior quality additives which were used, just to maintain the duplicitous picture of the pure milk [25,26].

Conclusion

The most frequent practice of milk adulteration was exercised by all milk intermediaries with the addition of extraneous water, after mixing of detergent, rice flour, starch, cane sugar, formalin, caustic soda, salt, urea, hydrogen peroxide, glucose, arrowroot, skimmed milk powder, vegetable oil and dalda for their profit. Due to the addition of various adulterants in milk especially by retailer, milk vender and milk collector may decrease physico-chemical quality, nutritional value and supply unhygienic milk to the end users.

Acknowledgement

Authors are very much grateful to Higher Education Commission Islamabad and Department of Animal Products Technology, Faculty of Animal Husbandry and Veterinary Sciences, Sindh Agriculture University Tandojam, Pakistan for providing financial liability and technical support to investigate the different trends of milk adulteration at province level.

References

  • Neumann CG, Harris DM, Rogers LM (2002) Contribution of animal source foods in improving diet quality and function in children in the developing world. Nutrition Research (22): 193-220
  • Hoppe C, Molgaard C, Michelson KF (2006) Cow’s milk and linear growth in industrialized and developing countries. Annual Review of Nutrition 26: 131-173.
  • Tipu MY, Altaf I, Ashfaq M, Siddiqui S (2007) Introduction. In Proceedings of the workshop on monitoring of chemical adulterants and hygienic status of market milk. Lahore, WTO-Quality Control Laboratory, Pakistan. p.7-39.
  • Javaid SB, Gadahi JA, Khaskheli M, Bhutto, MB, Kumbher S, et al. (2009) Physical and chemical quality of market milk sold at Tandojam. Pakistan Journal of Nutrition 29(1): 27-31.
  • Naz W (2000) The dairy sector. http://www. Pakistaneconomist.com.
  • Fakhar H, Walker FG (2006) The white revolution-Doodah Darya Pakistan. p.72.
  • Walker GP, Dunshea FR, Doyle PT (2004) Effects of nutrition and management on the production and composition of milk fat and protein. Australian Journal of Agriculture Research (55):1009-1028.
  • Butt MYM (2011) Seminar on Milk Anti-adulteration policy. Policy Draft: International executive summary dairy report, (IFCN) Pakistan Lahore.
  • Clare DA, Catignani, GL Swaisgood HE (2003) Bio defense properties of milk: The role of antimicrobial proteins and peptides. Current pharmaceutical design 9(16): 1239-1255.
  • Khaskheli M (2010) Dairy Laboratory Manual. Department Animal Products Technology, Faculty Animal Husbandry and Veterinary Sciences, Sindh Agriculture University, Tandojam: p.38.
  • AOAC (2005) Official methods of analysis of the association of official analytical chemists. Inc. Gaithersburg, USA.
  • James CS (1995) Experimental Procedures-estimation of major food constituents. In: Analytical Chemistry of Food. Blackie Academic and Professional and imprint of Chapman and Hall, Glasgow, UK. p. 71-135.
  • BSI (1993) Microbial examination of food and animal feeding stuffs. Enumeration of Enterobacteriaceae, In: British Standard Institute London, UK, p. 5763.
  • Barham GS, Khaskheli M, Soomro AA, Nizamani ZA (2014) Extent of extraneous water and detection of various adulterants in market milk at Mirpurkhas, Pakistan. International Organization of Scientific Research, Journal of Agriculture and Veterinary Sciences 7(3): 83-89.
  • Faraz A, Lateef M, Mustafa MI, Akhtar P, Yaqoob M, et al. (2013) Detection of Adulteration, Chemical Composition and Hygienic Status of Milk Supplied to Various Canteens of Educational Institutes and Public Places in Faisalabad. Journal of Animal and Plant Sciences 23(1): 119-124.
  • Ahmed AAH (2009) Milk adulteration by adding water and starch at Khartoum state. Pakistan Journal of Nutrition 8(4): 439-443.
  • Lateef M, Faraz A, Mustafa MI, Akhtar P, Bashir MK (2009) Detection of adulterants and chemical composition of milk supplied to canteens of various hospitals in Faisalabad city. Pakistan Journal of Nutrition (9): 139-142.
  • Manish MP, Singhal RS Kulkarni PR (2000) An approach to the detection of synthetic milk in dairy milk, 1. Detection of urea. International Journal of Dairy Technology 53(3): 987-991.
  • Nida S, Soomro AH, Sheikh SA, Khaskheli M (2013) Extent of water adulteration and its influence on physical characteristics of market milk. Pakistan Journal of Nutrition 12(2): 178-181.
  • Bhatt SR, Singh A, Bhatt SM (2008) Assessment of synthetic milk exposure to children of selected population in Uttar Pradesh, India. Indian Journal of Research (7):22-34.
  • Wadekar SB, Menkudale GV (2011) Physico-chemical quality of market milk in Nanded town. Vision Research Review 1(1): 27.
  • Zia U (2007) Improved market access and smallholder dairy farmer participation for sustainable dairy development. Consultancy Report CFC/FIGMDP/ 16FT. Lessons Learned Study. Islamabad, Pakistan.
  • Memon MM (2014) Surveillance of milk adulteration and its influence on physico-chemical characteristics of milk. A thesis submitted to Faculty of Animal Husbandry and Veterinary Sciences, Sindh Agriculture University Tandojam, Pakistan.
  • Barham GS, Shah AH (2016) Quality profile of raw milk supplied to households within Hyderabad city. Isra Medical Journal (8):134-138.
  • Aziz AS, Muhammad Khaskheli, Muhammad Awais Memon, Ghulam Shabir Barham, Israr Ul Haq, et al. (2014) Study on adulteration and composition of milk sold at Badin. Thesis submitted to Sindh Agriculture University Tandojam: p.21-36.
  • Ayub M, Ahmed Q, Abbas M, Qazi IM, Hattak IA (2007) Composition and adulteration analysis of milk samples. Sarhad Journal of Agriculture 23(4): 1127-1130.
  • Close

    Online Submission System

    Drag and drop files here

    or

    Browse Files
    ( For multiple files submission, zip them in a single file to submit. For file zipping software Download )