Volume 14, Issue 2, June 2016, Pages 64–66
Open Access
- National Agrarian University of Armenia, 74, Teryan Str., Yerevan 0009, Armenia
- Received 24 February 2016, Accepted 2 May 2016, Available online 24 May 2016
- Open Access funded by Agricultural University of Georgia
- Under a Creative Commons license
Abstract
Research
has been conducted in Lusadzor community of Tavoush province in Armenia
to determine the processability of milk samples collected from Jersey
and Simmental cows for cheese manufacturing. The chemical composition as
well as physical–chemical and technological parameters of the milk
samples have been analyzed experimentally. In addition, the researchers
estimated physical, chemical and organoleptic parameters as well as the
yield of the cheese produced from the bulk milk collected from Jersey
and Simmental cows. The results of the research proved that the milk
samples collected from Jersey and Simmental cows possess the necessary
physical–chemical and technological properties and can be used as
high-quality raw material for manufacturing brine-ripened (pickled)
cheese. The highest content of dry matter, observed in the milk
collected from Jersey cows, stemmed from the high contents of fat,
protein and minerals. The content of lactose (milk sugar) and physical
characteristics (density, freezing temperature) did not vary
significantly across the samples. The rennet clots formed in the milk
collected from Jersey cows were characterized by higher
structural–mechanical parameters and syneresis. Jersey milk possesses
the qualitative characteristics that best contribute to high cheese
yield, which allows for the most efficient cheese production. Cheese
manufactured from Jersey milk is distinguished by less water content,
higher fat and protein contents and higher organoleptic indicators,
which all together improve the quality of cheese turning it into a
highly competitive product.
Keywords
- Milk;
- Breed of the cows;
- Cheese-making properties of milk;
- Yield of cheese;
- Organoleptic parameters
Introduction
Cheese
is a highly-nutritious and biologically adequate foodstuff
traditionally consumed by the population of the Republic of Armenia as
part of the daily ration. Within the commodity pattern of the country's
retail turnover, the turnover of cheese is nearly equal to the total
turnover of other dairy products (as of 2008–2012, 0.3–0.7 and 0.5–0.8%
respectively) [1].
Cheese
manufacturing is a coupled process of concentration and biological
transformation of the milk components into gustatory and aromatic
compounds that determine the unique characteristics of the particular
cheese. Use of high-quality raw materials that provide for effectiveness
of physical–chemical processes and fermentation all along the cheese
making and ripening periods is the key factor in manufacturing cheese
with more intense flavor, rubbery and even texture.
The
key factors that determine the cheese yield are as follows: milk fat
and casein contents; quantities of the milk constituents (especially fat
and casein) lost during the process of cheese-making; water content in
cheese. The breed of cattle has particular effect on the cheese-making
characteristics of milk, as milk produced by different breeds of cow
differs in composition and some of its properties [2] and [3].
The
increasing importance of high-protein food products necessitates
well-targeted selective breeding for desirable characteristics that
contribute to increased economic efficiency of the industry. For the
foregoing reasons, our research focused on evaluating the quality of
milk collected from purebred Simmental and Jersey cows in Armenia as
well as the quality of dairy products produced from that milk.
Research data and methodology
From
February through September 2015, milk was collected from Jersey
(n = 20) and Simmental (n = 20) cows on the dairy farm of “Himnatavoush”
Development Foundation (Lusadzor village of Tavoush province) to
examine its physical–chemical and technological (cheesemaking)
characteristics. The bulk milk collected from the animals of the same
breed was used for production of cheese.
Both
tasks, namely the analysis of the physical–chemical and technological
characteristics of the milk and cheese and production of cheese, were
accomplished at the Department of Animal Product Processing Technology
of National Agrarian University of Armenia. The researchers used
generally accepted standard research methods. The fat and nonfat milk
solids (SNF) weight ratios in milk were measured using an EKOMILK-98
Ultrasonic Milk Analyzer; The Gerber method was used to determine the
fat weight fraction in cheese (ГОСТ1-3624-67).
To measure the protein and casein contents in milk, the researchers
used the Formol Titration Method. The density of the milk was measured
by using areometer (ГОСТ-3625-71). The dry matter content was measured
by drying the samples in an oven at 102 ± 2 °С (ГОСТ-3626-73). To
determine the content of minerals, the researchers used the ashing
technique, which is based on ignition of samples in an ash muffle at
700 °С. The organoleptic characteristics of the cheese were graded on a
100-point scale (ГОСТ-7616-55) [4].
The milk coagulating property was obtained by the rennet test (by Z. H.
Dilanyan), while the rennet curd tension was measured by means of the
Meshcheryakov's device [5].
Syneresis was determined by drainage test, based on the quantity of
whey separated within a period of thirty minutes from a rennet clot cut
in four pieces.
Research results
Analysis
of the physical–chemical properties of the milk collected from Jersey
and Simmental cows reveals that the protein and fat contents in the milk
produced by Jersey cows are higher by 0.6%, and 1.23% respectively.
Also, the weight content of casein is different. Jersey milk is the
richest in casein content. It contains 0.55% more casein than the milk
of Simmental cows (Table 1).
