scholarly journals The Effect of Lactation Number on Physico-Chemical and Microbiological Parameters of Milk from Small and Medium Bovine Farms located in Transilvania Region

Author(s):  
Ioan HAN ◽  
Otilia BOBIŞ ◽  
Liviu Alexandru MĂRGHITAŞ

Milk is a biological fluid where fats are distributed in microglobules (2-10 million/cm3), in an aqueous solution of proteins, carbohydrates and other substances. The main physico-chemical properties of milk are: density, viscosity, specific heat, boiling point, freezing point, pH and total acidity. Microbiological quality is represented by the presence or absence of pathogens or alterations, which can contaminate milk as a raw material. The comparative nutritional and microbiological quality of milk from three counties, from Transilvania Region, were fat percentage, total protein, casein content, lactose, pH, urea, total germ count (TGC) and somatic cell count (SCC). The best percentages of fat were obtained in Bihor County, with mean values of all lactations of 4.00%. This was followed by Hunedoara County with 3.97% and Alba County with 3.95%. The highest protein percentages were obtained in samples collected in Bihor County, with mean values of 3.57%, followed by Hunedoara County with 3.52% and Alba County with 3.51%. Most physicochemical indices fall within the normal limits, unanimously accepted by existing standards, but microbiological indices in some cases do not meet the requirements for the admission of raw milk.

2000 ◽  
Vol 25 ◽  
pp. 29-72
Author(s):  
P.F. Fox ◽  
T.P. Guinee

AbstractMilk and dairy products are major components of the human diet in Western countries, providing about 30% of dietary proteins and lipids. The current annual production of milk is 560 x 106 tonnes, of which 85, 11, 2 and 2% are bovine, buffalo, caprine and ovine, respectively. Although some raw milk is still consumed, the vast majority of milk is processed to at least some extent. Liquid milk is a major food item in all developed dairying countries, representing 30% of total milk production. The remainder is processed into one of several thousand products, making dairy products the most diverse and flexible group of food products. The flexibility of milk as a raw material resides in the chemical and physico-chemical properties of its constituents, many of which are unique. The principal constituents of milk can be modified by enzymatic, chemical and/or physical methods, permitting the production of new products. However, the concentrations and properties of milk constituents are variable and hence the processability of milk and the properties of dairy products are inconsistent, although much of this variability can be eliminated by employing modern technology, which exploits certain features of milk constituents. Today, most milk is processed in very large, highly mechanised and automated factories, where consistency in processing properties is essential. The resulting products are distributed through large wholesale and retail outlets, where consistency is, again, paramount. Finally, today's consumers expect consistency. The consistency expected by the processor, distributor and consumer can be achieved only if the properties of milk constituents are understood at the molecular level.This communication will describe:The chemical and physico-chemical properties of the principal constituents of milk, i.e. lactose, lipids, proteins and salts,Variations in milk composition and in the properties of its constituents and the influence of dairy husbandry practices thereon,Exploitation and significance of the chemical and physico-chemical properties of milk constituents in the production and properties of the principal groups of dairy foods, i.e. liquid milk products, cheese, butter, fermented milks, functional milk proteins and lactose.Process modifications which may be used to overcome variations in the properties of milk constituents.


Author(s):  
Mihaela TIŢA ◽  
Otto KETNEY ◽  
Ramona IANCU ◽  
Ramzan MUHAMMAD

Research aims at benchmarking the quality of raw milk supplied by four private farms in the county of Sibiu at a distance of about 25 km each for a period of three months (April, May, June 2010). Samples were subject to particularly microbiological measurements (total number of germ and somatic cells), physico-chemical (acidity, fat density, non-fat dry matter, protein and freezing point titre) by international standard methods. The results of the four farms show different variations of the parameters analyzed as follows: 55.5% of the samples fall in physico-chemical parameters of standard quality and 79% of the samples fall within the parameters of microbiological quality standard and within the limits provided by law


2013 ◽  
Vol 82 (2) ◽  
pp. 187-190
Author(s):  
Bohumíra Janštová ◽  
Pavlína Navrátilová ◽  
Michaela Králová ◽  
Lenka Vorlová

The freezing point of milk is an important indicator of the adulteration of the milk with water, but heat treatment may also affect its value. The aim of this study was determine freezing point of raw and heat treated sheep milk and its variation during lactation. The freezing point was determined in 42 bulk tank raw sheep milk samples and 42 pasteurized milk samples collected during lactation of sheep at one ecofarm in Moravian Walachia (Valašsko in the Czech Republic). The freezing point was determined in accordance with the standard ČSN 57 0538 using a thermistor cryoscope. The average freezing point of raw milk was -0.617 ± 0.052 °C, with a range from -0.560 to -0.875 °C. The freezing point was lower in the first months of lactation and increased at the end of lactation. The freezing point correlated (r = 0.8967) with the content of total non-fat solids. The average freezing point of sheep milk pasteurized at 65 °C for 30 min was -0.614 ± 0.053 °C, with a range from -0.564 to -0.702 °C. The median of freezing point differences between raw and pasteurized milk was 0.004 °C. Our study extends data about physico-chemical properties of sheep milk and registers for the first time specific changes in the freezing point value of sheep milk by heating.


Food Biology ◽  
1970 ◽  
pp. 19-23
Author(s):  
Nawal Abdel-Gayoum Abdel-Rahman

The aim of this study is to use of karkede (Hibiscus sabdariffa L.) byproduct as raw material to make ketchup instead of tomato. Ketchup is making of various pulps, but the best type made from tomatoes. Roselle having adequate amounts of macro and micro elements, and it is rich in source of anthocyanine. The ketchup made from pulped of waste of soaked karkede, and homogenized with starch, salt, sugar, ginger (Zingiber officinale), kusbara (Coriandrum sativum) and gum Arabic. Then processed and filled in glass bottles and stored at two different temperatures, ambient and refrigeration. The total solids, total soluble solids, pH, ash, total titratable acidity and vitamin C of ketchup were determined. As well as, total sugars, reducing sugars, colour density, and sodium chloride percentage were evaluated. The sensory quality of developed product was determined immediately and after processing, which included colour, taste, odour, consistency and overall acceptability. The suitability during storage included microbial growth, physico-chemical properties and sensory quality. The karkede ketchup was found free of contaminants throughout storage period at both storage temperatures. Physico-chemical properties were found to be significantly differences at p?0.05 level during storage. There were no differences between karkade ketchup and market tomato ketchup concerning odour, taste, odour, consistency and overall acceptability. These results are encouraging for use of roselle cycle as a raw material to make acceptable karkade ketchup.


2020 ◽  
Vol 14 (1(51)) ◽  
pp. 79-92
Author(s):  
I. V. Podorozhniaya ◽  
S. S. Vetokhin

The values of freezing point, titratable and active acidities, conductivity, water activity, humidity, nonfat milk solids the of samples of market bioyoghurt were analyzed. They significantly differ from the same row milk indicators. So, they demonstrated lower values of freezing point, active acidity, water activity, humidity, and increased values of titratable acidity and conductivity, and nonfat milk solids. A large dispersion of the studied products’ properties was found for each manufacturer production as well as between producers. Yoghurts with Bifidobacterium that were produced at the Brest region had the highest values of рН, nonfat milk solids and lowest values of freezing point and humidity. This fact evidences the manufacturer has a well-established technological process for the production of bioyogurt and traceability of raw milk supply. The boundaries of the confidence intervals of physical and chemical properties both by individual manufacturers and jointly were determined. A close relationship between conductivity and freezing point in bioyoghurts of some manufacturers has been found. The dynamics of their changes in last years is traced.


2016 ◽  
Vol 683 ◽  
pp. 596-600
Author(s):  
Aleksey Zarubin ◽  
Natalia Chukhareva

Significant attention is paid to the production of peat-based materials in modern days. The study explores the influence of natural peat thermal modification on its properties by applying class-modeling techniques. Modification of different types of peat is achieved by heating at 250 °C. The set of peat properties such as component composition, g-factor and IR-spectra is used to obtain data matrix. It is shown that class-modeling techniques, such as partial least-squares discriminant analysis (PLS-DA) and simple independent modeling of class analogy (SIMCA), allow estimating peat class (natural or modified) by a set of properties without prediction errors by using three latent variables. According to the results of classification, it is established that thermal modification can be considered as a means of regulating the composition and physico-chemical properties of natural peats as a raw material


2018 ◽  
Vol 10 (7) ◽  
pp. 196 ◽  
Author(s):  
Rogério Marcos de Oliveira Alves ◽  
Jacqueline Lemos Viana ◽  
Henrique de Abreu Cerqueira Sousa ◽  
Ana Maria Waldschmidt

The physico-chemical properties of honey produced by the stingless bee Melipona mondury from Atlantic Forest in the state of Bahia, northeastern Brazil were evaluated. The evaluated characteristics included: water content, electrical conductivity, pH, acidity, water activity, ashes, diastase, hydroxymethylfurfural (HMF), reducing sugars and saccharose values. The honey samples showed mean values of 29.18% for moisture; 391.5 μS for electrical conductivity; pH of 4.06; 34.3 meq kg-1 for acidity; 0.73 for water activity; 0.18% for ashes; 4.05 (Goethe unit) for diastase; 1.60% for HMF; 65.42% for reducing sugars; and 2.14% of saccharose. Only the diastase activity was above the limits accepted by the Technical Regulation for Identity and Quality of Honey (Brazilian Ministry of Agriculture and Supplies). Most parameters are according to those reported in honeys from other species of stingless bees in Brazil.


AGROINTEK ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 57-66
Author(s):  
Kukuk Yudiono

The main problem encountered in the production of tempeh was its raw material, namely soybeans dominated by soybean supplied from other countries, mainly dominated by imported products from the United States. The majority of tempeh craftsmen's perception is that imported soybeans are superior to local soybeans. This is of course unfortunate because it will further aggravate the competitiveness of local soybeans. This research was conducted to explore the advantages of local soybeans, especially from the physico-chemical aspects of imported soybeans. The research objective was to map the physico-chemical properties of local and imported soybeans as raw material for tempeh. One factor trial design was used, with soybean varieties (4 local and 1 imported) as a factor. Variables observed included: antioxidant, bulk density, swelling power, plant quality, seed size, WAI, WSI, protein, yield, and density. The results obtained: 1) antioxidant : Devon 1 imported soybeans, 2) bulk density: fourth of local soybeans = imported soybeans, 3) swelling power : Argomulyo = imported soybeans, 4) quality of  cooking: fourth of  local soybeans imported soybeans, 5) seed size : Grobogan and Argomulyo imports, 6) WAI:  Argomulyo and Demas imported soybeans, 7) WSI: Devon = imported soybeans, 8) protein: Grobogan and Detam imported soybeans, 9) density:  Bromo imported soybeans, 10) extraction value: Anjasmoro, Argomulyo, and Grobogan imported soybeans.


Author(s):  
Williams Nashuka Kaigama ◽  
Abu Emmanuel Benjamin ◽  
Ibrahim Usman ◽  
Thankgod Daniel

Due to the high demand for vegetable oil by soap industries, the quest for alternative raw material is on the increase. In this study, vegetable oil was extracted from the underutilise seeds of Lagenaria siceraria using n-hexane; The Physico-chemical properties of the oil were analysed: iodine value 65 Ig/100 g, acid value 2.50 mg/KOH/g, saponification value 256 mgKOH/g, pH 6.20, specific gravity 0.902, the refractive index of 1.47 and oil yield 52%. The properties of the oil were compared with oil extracted from other sources. The properties of the oil suggest it can use for both commercial and industrial purposes. The extracted oil was then used to prepared soap and its properties were compared with the properties of soaps prepared from other oils. The physicochemical parameters of the prepared soaps which include foam height, hardness, pH and cleansing power were evaluated. The soap made from Lagenaria siceraria seeds oil has foam height of 2.0 cm lower than palm kernel oil (2.1 cm) and higher than soya beans (0.55 cm). Soap made from Lagenaria siceraria seed oil has an appreciable degree of hardness and good cleansing power compared to soaps prepared from other oils. The pH of all the soaps prepared is within the standard of the regulating agency in Nigeria. From the result obtained, it shows the underutilised Lagenaria siceraria seed oil can use as an alternative raw material in the commercial production of soap.


Sign in / Sign up

Export Citation Format

Share Document