Specialty products made from goat milk

Although it may not be important in certain parts of the world, the contribution of goat milk to the economic and nutritional wellbeing of humanity is undeniable in many developing countries, especially in the Mediterranean, Middle East, Eastern Europe and South American countries. Goat milk has played a very important role in health and nutrition of young and elderly. Goat milk has also been known for its beneficial and therapeutic effects on the people who have cow milk allergy. These nutritional, health and therapeutic benefits enlighten the potentials and values of goat milk and its specialty products. The chemical characteristics of goat milk can be used to manufacture a wide variety of products, including fluid beverage products (low fat, fortified, or flavored) and UHT (ultra high temperature) milk, fermented products such as cheese, buttermilk or yogurt, frozen products such as ice cream or frozen yogurt, butter, condensed/dried products, sweets and candies. In addition, other specialty products such as hair, skin care and cosmetic products made from goat milk recently have gained a further attention. Nevertheless, high quality products can only be produced from good quality goat milk. The quality milk should have the potential to tolerate technological treatment and be transformed into a product that satisfies the expectations of consumers, in terms of nutritional, hygienic and sensory attributes. Taste is the main criteria used by consumers to make decisions to purchase and consume goat milk and its products. Typical goat taste is considered as a quality component in certain goat cheese products. Farmers can produce more value-added products for the economic sustainability of their business and the dairy goat industry in general.     

Study of human allergic milk whey protein from different mammalian species using computational method

Nowadays, safety and quality assessment of food used for human consumption have to consider by its possible contribution to the maintenance or improvement of the consumer''s health. Milk is an important food with many nutrients. Cow milk is an important source of energy, protein, vitamins and minerals for the growing child as well as adults. But, numerous cow milk proteins have been implicated in allergic responses and most of these have been shown to contain multiple allergic epitopes. The present study disclosed best alternatives to cow milk, which are not allergic and as good as cow milk in nutritional value. The in silico analysis of casein (alpha s1, alpha s2, beta and kappa) and beta-lactoglobulin, unveils that sheep milk is a more suitable alternate to cow milk for allergic infants and buffalo milk for allergic adult humans.     

Analysis of casein alpha S1 & S2 proteins from different mammalian species

Nowadays, the quality of any food used for human consumption is, to a considerable extent, considered by its possible contribution to the maintenance or improvement of the consumer's health. In developed countries there is increasing interest in goat milk and its derivates, the quality of which is considered of special importance in the light of current tendencies favouring healthy eating. In particular, goat's milk is a hypoallergenic alternative to cow's milk in the human diet. In the present work, we studied the casein alpha S1 and S2 proteins of cow, goat and sheep for comparative analysis. We found that the amino acid sequence of these proteins is almost same in goat and sheep but there are several changes at different base pairs when these two sequences are compared with cow. Prediction of secondary structures (GOR) was performed for alpha s1 and s2 proteins to gain functional insights. Our in silico study revealed considerable identity in chemical properties between goat and sheep but a considerable dissimilarity in cow with goat and sheep casein proteins. Moreover, the effect amino acid change on secondary structures in the three species is discussed. There was no significant difference found between goat and sheep alpha S1 and S2 proteins, so naturally both will be having same properties. The study concludes that sheep milk is another convenient alternative for the cow milk allergic children.     

Major proteins in goat milk: an updated overview on genetic variability

Milk and dairy products are very important in Mediterranean diet because of their health promoting and organoleptic properties. In many developing countries, goat rearing has a key role in livestock production. What makes goats so popular is their ability to provide high quality food under diverse climatic conditions and resilience to extreme and capricious environments. In the last years, the interest concerning caprine milk has been increasing also to find a new exploitation for local breeds. To promote the goat dairy products there is a clear need to know the quality and the technological aspects of milk produced. That being so, the purpose of this study was to review the available literature on the major goat milk proteins with a particular attention to recent findings on their genetic variability. Moreover, the main effects of different protein variants on milk yield and composition were also discussed.     

A comparative study of elemental composition of human breast milk and infant milk substitutes

Instrumental neutron activation analysis (INAA) and protoninduced X-ray emission (PIXE) analysis have been employed to determine the concentration of 13 elements in human breast milk, various infant formulas, and locally produced cereals from Nigeria, as well as from various infant formulas and natural cow and goat milk available in the UK. The study shows that if the locally produced cereal is to be used on a regular basis for babies in Nigeria, then their diet must be supplemented with essential trace elements. Furthermore, parents should be discouraged from giving their infants cow and goat milk because of the high concentration of major elements compared to human breast milk.     

Dietary lipids and forages interactions on cow and goat milk fatty acid composition and sensory properties

This review summarises the known effects of dietary factors on bovine and caprine milk fatty acid composition, as well as the regulation of cow and goat mammary lipid secretion. Special attention is given to fatty acids that could play a role for human health, such as saturated fatty acids, oleic acid, n-6- or n-3-C18 to C22 polyunsaturated fatty acids, trans isomers of C18:1 and C18:2, and isomers of conjugated linoleic acid (CLA). The main dietary factors taken into account are the nature of forages, including pasture, the forage:concentrate ratio and diet starch content, and the supplementation of dairy rations with crude or processed vegetable oils or oilseeds, and vitamin E. A particular emphasis is given to studies on interactions between these dietary factors, which show that there is a considerable plasticity of ruminant milk fatty acid composition. Despite the existence of several studies on the effects of dietary factors on the sensorial quality of milk and dairy products, there is a need to evaluate more deeply how the different feeding strategies could change the nutritional, sensorial and technological aspects of milk fat quality.     

Beneficial effect of goat milk on bioavailability of copper, zinc and selenium in rats

We studied the effects of dietary inclusion of freeze-dried goat and cow milk on the utilization of copper, zinc and selenium, and on the metabolic fate of copper and zinc, in rats using a standard (non-milk) control diet recommended by the American Institute of Nutrition and diets based on goat or cow milk. For animals given the goat milk diet, the apparent digestibility coefficient (ADC) of copper is similar to that obtained with the standard diet and higher than that in animals given the cow milk diet. The copper balance was higher among the rats given the goat milk and the standard diets than among those given cow milk. The ADC and retention of zinc and selenium were higher for the goat milk diet than for the other two diets. The copper content in the kidneys and in the femur was greater when the animals consumed a goat milk diet than a cow milk diet. Zn deposits in femur, testes, liver, kidney, heart and longissimus dorsi muscle were greatest with the goat-milk diet, followed by the standard diet and were lowest for the rats given cow-milk diet. This study shows that the goat-milk has an important and beneficial effect on the bioavailability of copper, zinc and selenium.     

Influence of goat and cow milk on the digestive and metabolic utilization of calcium and iron

The effects of goat and cow milk on the digestive and metabolic utilization of calcium and iron were studied in rats using a standard (non-milk) control diet. The digestive utilization of calcium is greater when the animals consume the goat-milk-based diet rather than that based on cow milk or the standard diet. The digestive utilization of iron, however, is similar for the goat-milk diet and the standard diet, and in both cases superior to that based on cow milk. The calcium content in the femur, sternum and Longissimus dorsi muscle (L.D. muscle) provides an indication of what happens during the utilization of the mineral; more is deposited when the rats consume a milk-based diet, particularly one based on goat milk. The iron content in the reserve organs, namely the liver and the spleen, is greater with the standard diet and the goat milk diet than with that containing cow milk. There is an obviously beneficial effect of goat milk on the metabolism of calcium and iron, which minimizes any interaction between the two minerals.     

用聚丙烯酰胺凝胶电泳和微流体芯片电泳鉴别6种液态奶

目的:研究6种液态奶制品蛋白电泳图谱的区别,建立奶制品的蛋白质学鉴别方法。方法:以5种纯牛奶、羊奶、水牛奶、骆驼奶、牦牛奶、黄豆浆为研究对象,通过SDS-PAGE和Agilent 2100微流体芯片电泳法进行分析比较。结果:骆驼奶、黄豆浆与其他研究对象的图谱有明显区别,而牛奶、羊奶、水牛奶、牦牛奶的差异却不是很大;采用微流体芯片电泳可有效地对豆奶、骆驼奶进行区分,还可在一定程度上鉴别牛奶、羊奶、水牛奶和牦牛奶。结论:Agilent2100系统作为一种新型半自动微流体芯片技术,可以快速、高效、准确地应用于液态奶制品的蛋白成分分析及鉴别。     

Organic goat production,processing and marketing: Opportunities,challenges and outlook

Organic goat production can be a rewarding livelihood and is gaining popularity. Global organic production has increased significantly annually over the past decade. Industry analysts forecast that demand in many markets will continue to grow at 10–30% per year, with the international organic market expected to grow to a volume of US$ 100 billion in the next decade. Organic dairy has shown stronger growth rates than organic meat production. In certain regions, the rise in organic milk production has increased the range of processed value-added organic milk and dairy products, and demand is out-stripping supply. The basic principles of organic goat production include care, ecology, fairness, and health as stated by the International Federation of Organic Agriculture Movement (IFOAM). Organic goat production can improve animal welfare, protect the environment, and sustain rewarding rural live styles. There are challenges when dealing with organic goat production, especially when one hopes to control intestinal parasites and to achieve adequate nutritional management. Exploring nutritional technology and disease prevention and treatment will eventually improve the production efficiency. There are various regulations in different countries that apply to certify organic foods, and the number of regulations is growing. One of the leading federations in international organic farming is IFOAM. The standards can be certified under IFOAM then can be recognized in many counties around the world. These regulations serve as branding effort, not only to protect the “organic” brand but also to promote it. Future of organic goat production will have to rely on continue search for alternatives in nutrition and disease prevention and control that are environmentally friendly, human health conscientious and animal considerate. Understanding organic goat farming from economic, ecological, and animal welfare perspectives will increase the likelihood of success.     

Effect of heat treatment on Listeria monocytogenes and Gram-negative bacteria in sheep, cow and goat milks

Sheep milk, compared with cow and goat milk, had a protective effect on Gram-negative bacteria and Listeria spp. heated at 65°C in a test-tube method. This effect was not solely due to fat content as cow milk artificially reconstituted to 10% homologous fat was not as protective. Listeria monocytogenes in whole sheep, cow and goat milks at an inoculum level of 1 times 10⁶ cfu ml^-1 was heated at 68°C for 15 s in the plate pasteurizer and survival was only detected in whole sheep milk after heating. Whole sheep, cow and goat milks containing high levels of L. monocytogenes (1 times 10⁶ cfu ml^-1) could not survive the current HTST plate pasteurization protocol.     

人乳寡糖2′-岩藻糖基乳糖的功能及其全细胞生物合成

母乳是新生儿最理想的营养剂。其中,人乳寡糖作为母乳的第三大固体组分,对新生儿的生长、发育及健康状况有重要影响,被应用于婴幼儿配方食品中。2′-岩藻糖基乳糖(2′-fucosyllactose,2′-FL),是分泌型母乳中含量最高的人乳寡糖,约占人乳寡糖总量的30%,具有重要的营养和医学价值。2′-FL能够促进婴幼儿生长发育、提高其认知能力、增强免疫力、抗过敏、抗病毒,以及调节肠道菌群,是极具潜力的新型营养强化剂。但是,2′-FL来源于母乳,依靠分离、提取获得大量2′-FL并不现实,因此亟需进行人工合成。人工合成2′-FL的方法有3种,包括：化学合成法、酶催化合成法和全细胞生物合成法。全细胞生物合成法因其成本相对低廉,且易于规模化扩大,而引起了国内外的广泛关注和研究。目前,国外很多跨国公司均开始布局2′-FL的工业化生产和应用,而我国在该领域尚处于研发阶段,因此,了解和掌握2′-FL的合成方法对我国开展2′-FL规模化生产具有重要的意义。本文旨在介绍2′-FL的功能特性,系统阐述其全细胞生物合成的关键技术和最新进展,讨论了针对限速步骤进一步提高产量的策略,旨在为2′-FL的合成和商业化生...     

Milk prolactin is biologically active

Fat-free milk from cow and goat was chromatographed on Sephadex G-100 and the prolactin (PRL) activity of the fractions determined by radioimmunoassay (RIA). A single prolactin component was observed in 3 cow and 3 goat milk samples with a Vf/Vt ratio of approximately 0.5. Fractions in which PRL was detected by RIA and fractions on either side of the PRL peak were combined, dialyzed and freeze dried. The fractions were assayed for biological activity using the pseudopregnant rabbit mammary gland in organ culture; the degree of secretory response was evaluated histologically. Milk prolactin was biologically active. In the RIA cow milk PRL and one of 2 samples of goat milk PRL gave dose response curves parallel with the bovine PRL standard. In the bioassay the dose response curves for cow milk PRL and ovine PRL were parallel while goat milk PRL was parallel when the results were compared on a weight basis but not on the basis of prolactin content of the preparations assayed by RIA.     

Cow milk fat interferes with prolactin radioimmunoassay

The concentration of prolactin (PRL) in fat-free cows milk was one-third that of whole milk while the values were similar for milk from the goat. A number of experiments were performed to determine if PRL was present in cow milk fat. The results indicate that cow milk fat introduces an artifact in the double antibody PRL RIA which overestimates the amount of prolactin in whole cow milk.     

An analysis of the volatile flavour compounds in a soft raw goat milk cheese

The major components of the musty cow rind cheeses were identified in a soft raw goat milk cheese as heptan-2-one, nonan-2-one, their corresponding secondary alcohols, some esters and sulfur compounds. Their production was associated with the manufacturing process and its influence on the microbial activity. However a specificity in goat cheese compounds was displayed concerning in particular limonene and some ketones, alcohols and aldehydes.     

Factors of a noninfectious nature affecting fertility after artificial insemination in lactating dairy cows. A review

After 80 years of the commercial application of artificial insemination (AI) in the cow, the method still has numerous benefits over natural insemination including worldwide gene improvement. The efficiency of insemination depends, among many other factors, on the delivery of an appropriate number of normal spermatozoa to the appropriate reproductive tract site at the appropriate time of estrus. The metabolic clearance of steroid hormones and pregnancy associated glycoproteins and the negative effects of different types of stress related to high milk production makes the high-producing dairy cow a good animal model for addressing factors affecting fertility. Nevertheless, extensive studies have shown a positive link between high milk production in an individual cow and high fertility. When a cow becomes pregnant, the effect of pregnancy loss on its reproductive cycle is also a topic of interest. This paper reviews the factors of a noninfectious nature that affect the fertility of lactating dairy cows following AI. Special attention is paid to factors related to the cow and its environment and to estrus confirmation at insemination. Pregnancy maintenance during the late embryonic/early fetal period is discussed as a critical step. Finally, the use of Doppler ultrasonography is described as an available research tool for improving our current understanding of the health of the genital structures and conceptus.     

Selenium content of milk and milk products of Turkey. II

Selenium content of 1028 milk and milk products of Turkey are presented in this study. The selenium content of human milk (colostrum, transitional, and mature milk), various kinds of milk [cow, sheep, goat, buffalo, paper boxes (3%, 1.5%, 0.012% fat), bottled milk, condensed milk (10% fat), mineral added milk (1.6%), and banana, strawberry, and chocolate milk] and milk products (kefir, yogurt, Ayran, various cheese, coffee cream, ice cream, butter, margarine, milk powder, and fruit yogurt) in Turkey were determined by a spectrofluorometric method. The selenium levels of cow milks collected from 57 cities in Turkey were also determined. Selenium levels in cow milk varied with geographical location in Turkey and were found to be lowest for Van and highest for Aksaray. The results [milk (cow, sheep, goat, buffalo and human) and milks products] were compared with literature data from different countries.     

Fluorometric determination of isocitrate dehydrogenase (EC 1.1.1.42; 1; NADP+ dependent) in ruminant milk

The enzyme isocitrate dehydrogenase (EC 1.1.1.42; 1; NADP⁺ dependent) located in the mammary cell cytosol mediates the synthesis of the majority of reducing equivalents for the energetically demanding milk fat and cholesterol synthesis in mammary cell cytosol. The present article presents a novel fluorometric method for quantification of the activity of this enzyme (IDH) in ruminant milk without pretreatment of the sample. Further, 493 goat milk samples – harvested before, during and after a nutritional restriction – were analysed for IDH activity i) with addition of extra substrate (isocitrate), and ii) with the intrinsic isocitrate solely. The IDH activity ranged from 0.22 to 15.4 units [nano moles product/(ml * min)] (un-supplemented) and from 0.22 to 45.6 units (isocitrate supplemented). The IDH activity increased considerably in milk during the nutritional restriction period concomitant with the increase in the metabolite isocitrate concentration and somatic cell count and returned to the initial level shortly after restriction period. The present ‘high through-put’ analytical method may be beneficial in future studies to phenotype modifications in mammary energy metabolism and milk fat synthesis, for which IDH activity may be a biomarker.     

OMICS-rooted studies of milk proteins,oligosaccharides and lipids

Milk has co-evolved with mammals and mankind to nourish their offspring and is a biological fluid of unique complexity and richness. It contains all necessary nutrients for the growth and development of the newborn. Structure and function of biomolecules in milk such as the macronutrients (glyco-) proteins, lipids, and oligosaccharides are central topics in nutritional research. Omics disciplines such as proteomics, glycomics, glycoproteomics, and lipidomics enable comprehensive analysis of these biomolecule components in food science and industry. Mass spectrometry has largely expanded our knowledge on these milk bioactives as it enables identification, quantification and characterization of milk proteins, carbohydrates, and lipids. In this article, we describe the biological importance of milk macronutrients and review the application of proteomics, glycomics, glycoproteomics, and lipidomics to the analysis of milk. Proteomics is a central platform among the Omics tools that have more recently been adapted and applied to nutrition and health research in order to deliver biomarkers for health and comfort as well as to discover beneficial food bioactives.