A molecular genetic approach for traceability of the source milk in cheese

SUMMARY Authenticity identification of different animal fo od products received in the last years an important attention. If in other EU countries pr oducts adulteration cases are quite rare, in Romania cow milk (produced at a lower price and in higher quantities), is often undeclared added into buffalo, goat or ewe milk. To avoid disl oyal competition between those producers who respect the law (concerning correct labeling) a nd those who don’t and for correct consumer’s information, several authenticity identi fication methodologies of dairy products were proposed (Vlaic et al., 2010). The majority of these are based on major mil k proteins analysis. The official European methodology for che eses authenticity identification is based on the IEF analysis of gamma casein fractions, foll owing β-CN plasmin hydrolysis, having the disadvantage that goat and sheep milk cannot be discriminated. In our previous studies we proved the existence of a new β-casein genetic variant in Romanian Buffalo breed, named C BT (Balteanu et al. , 2008; Balteanu, 2010). This makes the European methodology for cheeses authenticity identification unusable for discriminating buffalo and cow milk, due to the similar plasmin di gestion profile of β-casein C BT and cattle β-casein variants. In an extensive study we characte rized the major milk protein polymorphism in the main Romanian cattle, buffalo, sheep and goat breeds (Balteanu, 2010). Therefore the objective of this study was to test t he possibility of using all described allele to discriminate between the milk of these species. In terspecific milk mixtures were prepared from reference samples containing all described gen etic variants in the four farm species, as follows: cattle: buffalo, cattle: sheep, cattle: go at, buffalo: goat, buffalo: sheep, sheep: goat. Isoelectric focusing (IEF) of milk samples was perf ormed as described before (Balteanu et al. , 2007). Based on IEF behavior of each major milk protein and their specie specific genetic variants, the discrimination of each milk type, inc luding differentiation between goat and ovine milk, cow and Romanian buffalo milk, was possible. Our preliminary results indicate the applicability of this proposed method to establ ish authenticity of dairy products. The possibility of using the β-casein C BT as genetic markers for Romanian Buffalo cheeses

In goat milk, among the four caseins, αS1-casein (αS1-CN) locus is the most polymorphic. Eighteen alleles with four different expression levels have been identified so far in different goat breeds (reviewed by Caroli et al., 2006), having a significant influence on milk quality and its manufacturing properties (Grosclaude et al., 1994). In Carpathian goat breed we already reported a high degree of αS1-CN polymorphisms in Carpathian goat breed (Bâlteanu et al., 2007). However, no studies were done so far to quantify its effect on milk manufacturing properties and specific goat flavour. To correctly quantify the effect of this polymorphism, six different goat populations from central part of Romania were genotyped by IEF and PCR-RFLP, as described before (Pop et al., 2008). Three different experimental lots each consisting of 50 homozygous individuals in αS1-CN locus (AA, EE and FF) were organised and tagged with 3 different colours. Twenty litres of milk from each genotype group (AA, EE and FF) were processed in green cheese in the same conditions. Differences were observed concerning milk quality (whole protein content AA=3,71%, EE=3.26%, FF=3.40%; fat content: AA=3,99%, EE=3.52%, FF=3.57%; dry matter: AA=11.97 %, EE=11.04 %, FF=11.37 %), coagulation time (AA=16 minutes, EE=25 minutes, FF=40 minutes) and cheese yield (AA=2400g, EE=2060g, FF=2085g). EE cheese type was jugged as having the stronger specific goat flavour, AA the weakest, FF being intermediate. The results are pretty similar with those obtained in French and Italian goat breeds. Surprisingly in our study EE type milk had lower quality and the lower cheese yield as compared with AA or FF milk and the strongest goat flavour. Further studies are in progress to exactly quantify the effect of this polymorphism in Carpathian goat breed (PN II Project no. 52104/2008).

Goat milk, whose production is starting to develop in Algeria in recent years, has a number of advantages that even allow it to substitute cow's milk. It is a source of health benefits for humans; it contains more vitamins with a significant cheese yield than cow's milk. Our present study aims to study physicochemical, microbiological and for the first time trials of a fresh cheese (Feta) made from locally selected goat's milk in the region of Tlemcen and its 10 regions namely: Ouled Mimoun, Terny, Sebdou, Ain El houte, Remchi, Bensakrane, Maghnia, Sabra, Nedroma and Zenata. 27 goats from the local population were used for this study. The physicochemical quality (fat, density, conductivity, defatted dry extract, temperature, protein, mineral salts and lactose) of the milk sampled was measured using a LACTOSCAN Milk-Analyzer. Four flora (total germ, fecal coliform, Staphylococcus aureus and salmonella) were chosen to test the microbiological quality of the milk. The results obtained show that the good physicochemical quality of milk studied in all regions except the two regions of Nedroma and Maghnia showing a high fat content. A total absence of contaminations for the three types of fecal coliform flora, Staphylococcus aureus and Salmonella nevertheless for the total germs are found in all sampled regions. These results show that healthy goats hence the good practice of milking is applied during sampling. The manufacture of cheese type feta based on goat's milk was made in good conditions (raw material, hygiene, mechanical work ...) which led to a cheese of microbiological quality and nutritional and an interesting yield. The good breeding condition with a balanced diet gives a good quality of the milk and consequences of these results give an excellent forming thanks to the professional techniques of manufacturing a good feta cheese.

In goat ?S1-casein locus, 18 alleles with four different expression levels have been identified so far having a significant influence on milk protein, casein, fat contents, manufacturing properties and cheese yield. In Romania, unimproved Carpathian goat breed exhibits a high heterogeneity concerning milk quality. The goal of the present study was to investigate aS1-casein polymorphisms in some populations from the central part of Romania, in order to further establish the nature of milk protein content variation. Genotyping was carried out on 507 milk samples (belonging to 5 populations from Transylvania). Allele frequencies on the six loci coding for the major milk proteins were calculated.

The purpose of the research is improving the quality and technological properties of milk from black-and-white cows. The research was conducted on first-calf cows of a black-and-white breed in LLC «Dusym» of the Atninsky district of the Republic of Tatarstan. Three groups of experimental cows were formed depending on the genotype of CSN3 and DGAT1, which have equal lactation month. Cheese making milk obtained from cows with different allelic variants of the kappa-casein and diacylglycerol O-acyltransferase genes was studied. DNA testing was performed on the CSN3 and DGAT1 genes of experimental cows and allelic variants of these genes were determined by polymerase chain reaction followed by analysis of restriction-site polymorphism. It was found that milk of cows with the genotype CSN3 AB and CSN3 BB, when exposed to rennet, showed a better yield of a dense casein clot (80 and 100%) and separation of serum (P <0.05), with a shorter coagulation time (20.3 and 16.5 min; P <0.05-0.01). According to the DGAT1 gene, first-calf milk with the allelic variant DGAT1 AK and DGAT1 KK had the advantage, respectively, 86.7% and 85.7%, 24.0 and 25.7 minutes. The worst milk coagulation time is typical for CSN3 AA group - 29.5 minutes and DGAT1 AA one - 30.4 min. In terms of milk coagulation time, type II (15-40 min.) groups have the genotype CSN3 AB and CSN3 BB with the largest share of cows in the herd - 80.0 and 71.4% and with the genotype DGAT1 AK and DGAT1 KK - 86.6 and 85.7%, respectively. Thus, milk obtained from cows with the kappa-casein gene allele B and the diacylglycerol O-acyltransferase gene allele K gene in the genotype has the best cheese-making properties.

Over 3 million liters of fresh cow's milk and 1 million liters of fresh goat's milk are produced in Trinidad and Tobago annually. Eighty percent of the cow's milk is sold to the Swiss food and beverage giant Nestle at a subsidized price of 2.15 TTD/L. The state through the Ministry of Food Production contributes a further 1.50 TTD for every liter produced by registered dairy farmers. Goat's milk is sold as pasteurized milk at 40 TTD/L from individual small-medium farmers. Acidified dairy products use milk processing techniques to convert fresh milk into healthy products with extended shelf life. Cunently, several foreign brands of cottage cheese and yoghurt are found on supermarket shelves, with an average retail price of 80 TTD per 600g and 7 TTD/30 mL respectively. 5 L of fresh milk yields approximately 2.2 kg of cottage cheese or 3 L of yoghurt. Both products can be easily made and are in high demand because of their neutraceutical properties by dieters, immuno-compromised and lactose intolerant persons. The objective of this study is to evaluate the economic feasibility of utilizing fresh milk from dairy farmers to produce fresh yoghurt and cottage cheese for the domestic market. Trinidad and Tobago's dairy industry has the potential for creating employment and ensuring food security by processing fresh milk into acidified dairy products to meet the local demand for these products.

The majority of sheep and goat milk produced in the world is transformed into cheese, therefore, feeding is a major factor affecting the quality of sheep and goat milk and, hence sheep and goat cheese quality. This discussion is an attempt to explore the influence of nutrition on milk yield and major milk components in sheep and goats. Nutrition is a vital component in an attempt to maximise milk synthesis in small ruminants, as a result correct feeding management is desirable through appropriate estimation of roughage to concentrate intake in order to optimize the utilization of feed supplements. It is suffice to suggest that feeding high producing dairy animals may be a major constraint in milk production, which implies greater attention to diet composition, feed quality, and the physical form of feedstuffs is required. The rate and extent to which a dairy sheep and goat is capable of drawing upon body reserves to meet the energy requirement at different stages of lactation is critical in determining her ability to produce and sustain a high level of milk production. In order to increase sheep and goat milk production, and to ensure high feed efficiency, dairy farmers need to pay close attention to nutritional requirement of dairy animals which may differ during different stages of lactation.

This PhD research is part of a project addressed to improve the quality of Grana Trentino production. The objectives were to evaluated if milk storage and collection procedures may affect cheese-making technology and quality. Actually the milk is collected and delivered to the cheese factory just after milking in 50 L cans without refrigeration or in tanks cooled at 18 °C. This procedure is expensive (two deliveries each day) and the milk quality is difficult to preserve as temperatures are not controlled. The milk refrigeration at the farm could allow a single delivery to the dairy. Therefore it could be a good strategy to preserve raw milk quality and reduce cheese spoilage. This operation may, however, have the drawbacks of favouring the growth of psychrotrophic bacteria and changing the aptitude of milk to coagulation. With the aim of studying the effect on milk and cheese of traditional and new refrigerated technologies of milk storage, two different collection and creaming technologies were compared. The trials were replicated in three cheese factories manufacturing Grana Trentino. Every cheese-making day, about 1000 milk liters were collected from always the same two farms in the different collection procedures (single or double). Milk was processed to produce 2 wheels of Grana trentino every day. During the refrigerated trials, milk was collected and stored at the farm in a mixed tank at 12 or 8 °C and then was carried to the dairy in truck once a day. 112 cheese making day were followed: 56 for traditional technology and 56 for the refrigerated one. Each one of these two thechnologies lead to different ways of creaming: long time in the traditional one and shorter in the new one. For every cheese making day we recorded time, temperatures and pH during the milk processing to cheese. Whole milk before ceraming, cream and skim milk after creaming, vat milk and whey were sampled during every cheese-making day for analysis. After 18 months ripening we opened 46 cheese wheels for further chemical and microbiological analyses. The trials were performed with the aim of: 1 estimate the effect of storage temperatures on microbial communities, physico-chemical or/and rheological differences of milk and skim milk after creaming. 2 detect by culture dependent (plate counts) and indipendent (DGGE) methodolgies the microbial species present in whole, skimmed milk, cream and cheese sampled under the rind and in the core; 3 estimate the physico-chemical characteristics, the proteolytic activity, the content of free aminoacids and volatile compounds in 18 months ripened Grana Trentino cheeses from different storing and creaming of milk technologies. The results presented are remarkable since this is the first in-deep study presenting microbiological and chemical analysis of Grana Trentino that even if belonging to Grana Padano Consortium, it is clearly different in the milk and in the manufacturing technology.

Many microorganisms isolated and characterized during the past century have received considerable attention from the pharmaceutical and/or food fermentation industry because of their potential biotechnological interest. Lactic acid bacteria (LAB), particularly those belonging to beneficial and nonpathogenic genera (Lactococcus, Lactobacillus, Leuconostoc, Oenococcus, and Streptococcus), have traditionally been used in the food industry. They also play an essential role in the dairy industry due to the tremendous level of human consumption of several important fermented products, mainly cheese and acidified/fermented milks. In the USA, more than 4.6 million tons of cheese and more than 1.3 million tons of yogurt were produced in 2005 [1], whereas in the European Community (EU-25) more than 8 million tons of cheese and 6.9 million tons of acidified/fermented milk were produced in 2003 [3]. These figures correspond to a global sales value that surpasses US$ 28.44 billion, with the global sales value of cheese representing about 30% of total dairy-product sales [2]. Nowadays, more than 500 kinds of cheese are manufactured worldwide, and the many varieties are derived from modifications in cheese-making techniques. However, the fermentation process whereby milk is transformed into cheese has not changed to any great extent since humans discovered the process as a means of preserving food (the fermentation of milk dates back to ~3000 BC). Cheese is a dynamic biochemical product and, unlike many processed food products for which stability is essential, it undergoes significant changes during ripening. The unripe curds of many varieties of cheese have bland and largely similar flavors. However, the sequential actions of cheese microbiota and the interactions among the different microorganisms during the ripening period result in the flavor compounds that characterize each variety. Acidifying lactococci species usually occur as dominant bacteria early in the ripening process. Afterwards their numbers decrease as they give way to lactobacilli, which, due to their higher versatility for fermentation, can survive in cheeses at stages when concentrations of major carbohydrates and free water decrease, whereas the sodium chloride load increases. Apart from the above-mentioned major genera of LAB, other bacteria, including non-starter LAB and non-lactic-acid bacteria, as well as some fungi (yeasts, moulds), staphylococci, micrococci, coryneform bacteria, and propionic acid bacteria, which develop in the product particularly during the maturation phase as secondary microbiota, are often responsible for the intensity of flavor in many dairy products. The production of a wide range of antagonistic primary and secondary metabolites, including organic acids, diacetyl, CO2 and even bacteriocins, affects the complex dynamics of microorganisms in cheese. Thus, a well-founded understanding of the microbial balance in this special living ecosystem is essential to improve older varieties of cheese and to develop new ones. Due to the dairy market’s continuous growth, commercial cultures have conventionally been selected to obtain greater quantities of product, homogeneous quality of the end product, and short production times, with the final goal of satisfying the preferences of consumers. Most varieties of commercially important cheeses are manufactured worldwide by means of commercial starter cultures of generic composition (including acidifying and aromatic diacetyl-producing lactococci strains and sometimes also leuconostocs and lactobacilli strains). In Europe, Asia, Africa, and Latin America, however, there are regions where fermented products are still manufactured traditionally. In global markets, these fermented products are now highly appreciated and are considered to be of premium value because of their flavor characteristics, which are not found in varieties of cheese produced industrially. In Europe, such products are elaborated according to well-established rules governing the production of registered designations of origin. Protected designations of origin (PDOs) apply to foodstuffs that are produced, processed, and prepared in a given geographic area using recognized

Despite numerous studies since decades, transition period of dairy cows remains a big issue for both researcher and farmers. The endocrine changes that characterize this period expose the animals to metabolic imbalance, immune depression and oxidative stress. This situation results in the emergence of metabolic and infectious disease in addition to reduced and impaired milk production, that finally lead to the 15% of culling occurring in the first weeks of lactation. Therefore, several strategies have been put in place in order to improve health and welfare of transition cows, taking into account environment, nutrition and management aspects. The main purpose of this work is to investigate through 3 studies the effects of some of these strategies. In the first study, the effects of overcrowding during dry period were evaluated on stress related blood markers, behavior and welfare of animals. Overcrowded cows showed higher blood level of dehydroepiandrosterone (DHEA) and cortisol than controls and a restlessness behavior. The second study aimed to investigate the impact of an immunomodulant feed supplement (Omnigen-AF) fed to 190 cows from dry off to 150 DIM, on their health and milk composition and quality. Supplemented cows, compared to controls, had lower incidence of postpartum disease and lower culling rate within 60 DIM. Milk production and quality was not influenced by the treatment except for a reduction of SCC among Holstein cows. The last study evaluated the consequences on quality of milk and Parmigiano Reggiano cheese of an antiketotic treatment (Kexxtone). Despite the great concern on this aspect among cheese producers, the treatment didn’t impaired nor milk nor cheese production, confirming the usefulness and safety of this treatment for the prevention of ketosis. Overall, this thesis confirms the need and the effectiveness of different strategies that aimed to improve transition dairy cows health and their milk production.

The factors influencing the amount and composition of produced milk can be divided into two groups, namely internal and external factors. This is very important to remember when evaluating the milk quality and in the improvement of milk yield and composition in a dairy enterprise. Of the external factors it is possible to mention a few: litter size, duration of dry period and stage of pregnancy. The present discussion explores the significance of litter size, duration of dry period and pregnancy on milk yield and composition in dairy production. In goats and sheep dams bearing twins or triplets had higher milk yield than single bearing dams, and this significant increase in milk production in these dams that carried twins and triplets was followed by an increase in lactation length. Due to the amount of milk animal produce, the drying-off process is often more complicated for dairy animals (cattle, goats and some sheep). However, this period is essential to enables dams to regain the body condition needed to support the subsequent pregnancy and lactation. The majority of dairy animals dry off spontaneously because of the aforementioned natural decrease in daily milk production. The length of dry period influences milk production in the subsquent lactation, with shortening of the dry period showing a markedly negative effect on milk performance of dams. Lactating animals should have an opportunity to rest and regenerate mammary tissue between lactations. F or optimal dairy animal performance in the next lactation, lactating animals should have an opportunity to rest and regenerate mammary tissue between lactations. The amount of produced milk and its composition are influenced by the stage of pregnancy: in the first half of pregnancy it is not possible to observe any pronounced changes while in the second stage of pregnancy can observe a gradual decrease in milk production as well as an imcrease in levels of individual milk components. During pregnancy and the first few days postpartum, milk supply is hormonally driven – this is called the endocrine control system . This implies that in the course of lactation, changes in milk production are caused by changes in activities of the endocrine system that are caused by hormones sectreted by pitiutary gland (hypophysis cerebi) and placenta. During the latter part of pregnancy, the mammary gland is making colostrum, but high levels of progesterone inhibit milk secretion resulting reduced milk yield. Progesterone influences the growth in size of alveoli and lobes; high levels of progesterone inhibit lactation before birth. Progesterone levels drop after birth; this triggers the onset of copious milk production. Estrogen stimulates the milk duct system to grow and differentiate. Like progesterone, high levels of estrogen also inhibit lactation, while the hormone prolactin must be present for milk synthesis to occur.

Policy, administration and industry need medium-term projections of the expected developments in the agri-food markets for their decision-making processes. The EU Commission presents such projections for the EU as a whole in December of each year. Those projections and their assumptions regarding policy and macroeconomic developments are depicted to the level of individual EU Member States with the exception of Luxembourg, which is included in the figures of Belgium, by applying the partial equilibrium model AGMEMOD. The working paper briefly describes the approach to establish projections for the EU Member States. The projections cover the markets of main agricultural products, in particular for cereals and oilseeds (rapeseed and sunflower seed), livestock (cattle, pigs, goats and sheep), meat (beef, pork, and poultry), milk and dairy products (drinking milk, butter, cheese, skimmed milk powder, whole milk and semi-skimmed milk powder). The outcomes comprise items like areas, livestock numbers, yields, production, trade and use, as well as prices. The individual projection results are displayed in tables.

Since the stepwise reduction of intervention prices combined with watered down conditions and suspended export refunds, respectively, the EU dairy industry faces new challenges regarding wild price fluctuations originally caused in third countries. In the past, the EU domestic market was insulated as far as possible from world markets. However, today global prices could affect prices even at the level of consumers, but more directly at the level milk producers. Volatility noticeable increased with the price peak in 2007, followed by the drop in 2008, and a new price boost in 2010. Additionally, reduced security in marketing of butter and skimmed milk powder led to higher processing share of cheese which is not only exported but also increasingly consumed within the EU. Analyzing time series data of dairy products’ prices illustrates price fluctuations at different levels of the supply chain. Particularly, retail prices are less volatile than milk producer prices. Therefore, it is often assumed that retailers do not completely pass on downward movements of producer prices to consumers or, vice versa, and assumption encouraging debates on market power, margins and price transmission in the supply chain. German retailing is characterized by a high of market concentration and by a predominance of discounters, displaying a leading position in price negotiations with dairies or wholesalers. Thus, it can be argued that retailers adversely affect dairies who, in turn, affect milk producers. From this follows price transmission asymmetries differ across different levels of the supply chain, and volatile world market prices induced may affect the lower part of the supply chain negatively. However, price transmission has been analyzed in various studies before, mostly analyzing price transmissions between retailing and consumer level. Thus, they abstract from effects of intermediate levels (wholesale, world market). Therefore, the objective of this paper is to investigate the transmission of milk prices from the farm to the retail level and to detect possible asymmetries, leading in the case of world market price fluctuations to additional problems in the German supply chain. The focus is on the German cheese market whereby regime specific effects are tested e.g., the reduction of EU market support which has major impacts on price transmission. Additionally, the change in the product mix and the increased export orientation of German dairies also affect price transmission. In the analysis monthly data from January 1990 to October 2011 for producer prices of raw milk, wholesale and consumer prices for cheese as well as prices in international trade with cheese are considered. Institutional prices were generated on a monthly basis, thus, capturing dates of change in intervention prices and of export refunds. Applying a subset of model specifications based on error-correction representation asymmetries are studied, whereby the seasonal pattern of data is filtered out.

In sheep, the polymorphism of major milk proteins is reduced as compared with other ruminant species, like cattle and goats. As in other ruminant species, in sheep these polymorphisms were studied relative to milk quantity, quality and it’s manufacturing properties or for authenticity identification of dairy products. In Romania, data concerning the characterization of the sheep breeds in the six loci codifying for major milk proteins genes are almost absent. The importance of sheep milk in Romanian cheese industry makes the knowledge of major milk proteins polymorphism in this specie particularly important. Therefore, a number of 282 individuals belonging to five Romanian breeds: Turcana, Carabasa, Tigaie (white and rusty varieties), Cluj Merinos, Botosani Karakul (black, dark grey, brown, light grey, pink and white varieties), were genotyped by IEF in the six loci coding for major milk proteins. In the sheep breeds studied, the milk protein polymorphism was much reduced, the most polymorphic being ?-LG locus, in which two allele were identified, namely A and B. The A allele had a higher frequency as compared with B allele in Turcana, Carabasa, Cluj Merinos and Karakul breed, respectively. The B allele had a higher frequency in Tigaie breed, white and rusty varieties.

Background: Assessment of dairy products can identify the presence of heavy metals in them that poses a serious threat to human health and is a major concern on a global scale. Objective: The aim of this research was to evaluate the heavy metal concentrations in dairy products and their potential risks in urban areas in Bushehr city, Iran. Materials and Methods: A total of 71 dairy product samples (16 milk, 14 yoghurt, 15 cheeses, 13butter, 11 dough, and 12 creams) were collected randomly from dairy shops in Bushehr city, Iran and analyzed by using a flame atomic absorption spectrophotometer. Results: The results of this research showed that the concentrations of lead in cream and butter were significantly higher than in milk and yoghurt samples (P