Residues In Milk Research Articles

Прогнозирование количественных характеристик молока на основе инфракрасной спектроскопии с применением методов машинного обучения

Fourier transform mid-infrared spectroscopy is a fast and cheap way to analyze cow's milk samples to determine fat, protein, lactose and other quantitative and qualitative indicators of milk quality. Modern tools for data analysis will reveal the relationship between different pairs of quantitative and qualitative characteristics of milk. Purpose of the study. Perform predictions on some key milk quality traits based on infrared spectroscopy data to study the accuracy of the developed mathematical model. Methods. The work was carried out in the winter period of 2022 on the basis of an experimental herd of Holsteinized black-and-white cattle (Krasnodar Territory). The analysis of milk traits was carried out with an automatic analyzer MilkoScan (FOSS) using the method of infrared spectroscopy by unloading the obtained spectra when analyzing the composition of raw milk. 23 indicators of the quantitative milk traits were studied: mass fraction of fat, protein (true and total), lactose, DSMR (dry skimmed milk residue), dry matter, casein, traces of acetone and beta-hydroxybutyrate, urea, freezing point, acidity of milk, myristic, palmitic, stearic, oleic fatty acids (FA), long-chain fatty acids, medium-chain fatty acids, short-chain fatty acids, monounsaturated and polyunsaturated fatty acids, saturated fatty acids, trans fatty acids. Methods based on linear regression, approaches to the regularization of the linear regression model (Ridge, Lasso and ElasticNet), as well as polynomial regression, the partial regression method (PLSRegression) and the Bayesian regression method for the problem of predicting key features of milk traits were considered. A method for reducing the dimensionality of infrared spectroscopy data is implemented based on the algorithm of random search of readings along the length of the window, and the most significant features are identified. Results. Models have been developed for predicting six main indicators of milk quality – mass fraction of fat ('Fat'), mass fraction of casein ('Cas.B'), fatty acids – myristic ('C14:0') and oleic ('C18: 1'), monounsaturated ('MUFA') and polyunsaturated fatty acids ('PUFA') – with an average absolute error not exceeding 0,016. Conclusion. The results obtained in the course of the study will further improve the predictive ability of the equation for determining the quality and composition of milk according to new breeding traits of milk productivity, reduce analysis costs and monitor the health of animals at an early stage.

Assessment of vegetable and animal products in the Murmansk region within the implementation of the federal project “Public Health Promotion”

Monitoring studies of the quality of food products of plant and animal origin, including vegetable oils, some confectionery products and dietary supplements were carried out in the Murmansk region as a part of the implementing the federal project “Public Health Promotion” of the National Project “Demography”. Within the framework of monitoring studies, data allowing to evaluate the quality of food products in circulation on the territory of the Murmansk region were obtained, the share of products, up to 12% of the volume of the studied range not meeting the established requirements in safety quality indicators is revealed. The highest percentage of food products that do not conform to the technical regulation requirements is defined in the category of animal products and made up 7.8% of the total amount the of studied samples, the second place (2.5%) is given to the products of plant origin, other products – 1.8% complete the list. Toxic elements, pesticides, antibiotics, preservatives, mycotoxins, nitrates, dry low-fat milk residue, genetically modified enzymes (microbial transglutaminase) and sanitary-indicative microorganisms were determined among the safety indicators. Products of animal origin like eggs, milk, yogurt, kefir, sour cream, cake cheese, cheeses, condensed milk, butter, bockwurst sausages, sausages, were not safe for the consumer as a result of violating the production technology, including storage conditions failure, the use of low-quality raw material, or product falsification. The assessment of apples, cucumber, tomato, sunflower and olive oil, cookies and dietary supplements samples showed unsatisfactory results in the residual content of pesticides, nitrates, toxic elements, antibiotics and peroxide.

Quantitative Studies on Aflatoxin M1 Residues in Milk and Some Dairy Products

Quantitative Studies on Aflatoxin M1 Residues in Milk and Some Dairy Products

In Vitro Probiotic Characteristics and Whole Genome Sequence Analysis of Lactobacillus Strains Isolated from Cattle-Yak Milk.

Simple SummaryCattle-yak milk is rich in numerous bioactive substances that function beyond their nutritive value. Given the high content of conjugated linoleic acid (CLA), this exponent suggests a potential role for cattle-yak milk in preventing cancer, heart disease, and metabolic disorders, such as diabetes. It is expected to isolate probiotic strains with natural and excellent characteristics in optimizing human health. However, little research data and much fewer studies on probiotics from cattle-yak milk are reported. Therefore, in the present study, the beneficial strains from cattle-yak milk were identified to evaluate probiotic characteristics of potential strains, and to screen potential probiotics with an emphasis on making better use of milk in such extreme climatic environments. These findings support the potential application of cattle-yak milk in human health, animal food processing, and drug production in the future as a potential candidate for probiotics.Cattle-yak milk is an important raw material and an indispensable source of high-quality food for local farmers and herdsmen to produce ghee, milk residue, yogurt, and other dairy products. In this study, Lactobacillus strains were isolated from cattle-yak milk for potential probiotic candidates using a series of in vitro tests, including probiotic characterization and safety evaluation (antibiotic susceptibility and hemolytic ability). The results found that the Lactobacillus rhamnosus CY12 strain showed a high survival rate in bile salts, under acid conditions, and in the gastrointestinal juice environment, as well as showing high antimicrobial activity and adhesive potential. The safety evaluation showed that all strains were considered non-hemolytic. In addition, the whole-genome sequencing indicated that the strain CY12 spanned 2,506,167 bp, with an average length of 881 bp; the GC content in the gene region (%) was 47.35, contained 1347 protein-coding sequences, and accounted for 85.72% of the genome. The genome annotation showed that genes mainly focused on the immune system process, metabolic process, carbohydrate utilization, carbon metabolism, galactose metabolism, and biological adhesion, etc. This study revealed that the Lactobacillus rhamnosus CY12 strain might be an excellent potential probiotic in the development of feed additives for animals and has the ability to promote health.

Analysis of Pesticides Residues in Breast Milk of primiparous and multiparous women in Gilgit

Milk contains all the essential nutrients like fats, proteins, and minerals. The utilization of contaminated food can induce a proportion of pesticides in the body. The main purpose of the study was to determine the pesticide residues and current status of breast milk in primiparous and multiparous mothers. In a current study, a total of 50 samples were collected from different areas of District Gilgit and Astore. The pesticides cypermethrin, deltamethrin, and chlorpyrifos were analyzed using gas chromatography. The presence of cypermethrin in 10 samples was in a range 0.00 – 0.012 mg/kg, while the detection of Deltamethrin in 07 with variation from 0.000.12mg/kg. Whereas chlorpyrifos was found in 05 samples with the ranges of 0.00-0.0062 mg/kg. Residue level was quite higher in urban areas than rural areas. The multiparous women had prominent residues level than primiparas and the concentration of Deltamethrin was higher than other pesticides. All the pesticides residues levels in the breast milk of primiparous and multiparous mothers were within the permissible limits of WHO. Yet the women of these areas are not vulnerable but prolong exposure may pose a serious threat to neonatal and maternal health and other relevant reproductive issues. To manage the risk of milk contamination in the future, the demand for public awareness campaigns and the adoption of alternative clean approaches to control pests and other disease-spreading vectors in the best interests of public health seems reasonable.

Tungsten disulfide (WS2)/fluorescein ratiometric fluorescent probe for detection of cefixime residues in milk

In this research work, it has been reported a ratiometric fluorescent sensor based on tungsten disulfide quantum dots (WS2 QDs) and fluorescein for the determination of Cefixime (CEF). When excited by radiation of 400 nm wavelength the probe illustrates dual emissions centered at 460 nm and 510 nm. CEF quenches the fluorescence (FL) intensity of fluorescein (510 nm), while it doesn't affect the FL emission of WS2 QDs at 460 nm. The change in the ratio of the two peaks (F460/F510) of the prepared sensor (WS2 QDs/fluorescein) is linearly proportional to the CEF concentration in the range of 200–2.500 ng/mL with a limit of detection (LOD) of 45 ng/mL. Hence, the proposed probe can be successfully used for CEF quantification in the milk samples.

POLYMORPHISM OF THE Β-LACTOGLOBULIN GENE AND DAIRY PRODUCTIVITY OF DIFFERENT SHEEP’S GENOTYPES

POLYMORPHISM OF THE Β-LACTOGLOBULIN GENE AND DAIRY PRODUCTIVITY OF DIFFERENT SHEEP’S GENOTYPES

Research of quality indicators of parfe ice cream with vegetable fillers

The ice cream market is one of the developed segments of the food industry of Ukraine. Ice cream is a frozen product that is consumed all over the world. The work aimed to investigate the quality of parfait ice cream with vegetable fillings. The selection and justification of the components of the system, namely quail eggs, celery root, spinach leaves, was based on literature data and regulatory documentation, as well as laboratory data. Celery and spinach puree was chosen as one of the recipe components of ice cream, and the peculiarities of its preparation were studied. Parfait ice cream recipes with different ratios of vegetable fillers and pumpkin flour have been developed. The physiological and organoleptic parameters of ice cream with additional pumpkin flour, celery, and spinach puree were studied. According to the obtained results, the optimal content of pumpkin flour in ice cream is equal to 2–4 %, and vegetable puree – 25–35 %. It has been proved that pumpkin flour significantly affects the structural characteristics of ice cream mixes. They were melting resistance increases from 100 to 145 minutes. When increasing the flour content to 4 %. The dry matter content in ice cream varies depending on the amount of vegetable puree and pumpkin flour. However, the mass fraction of fat and dry nonfat milk residue does not change because the experimental samples were developed based on the composition of the control sample. Studies show that the new frozen dessert retains microbiological stability for six months. The combination of vegetable and dairy raw materials with pumpkin flour and quail eggs in the production of parfait ice cream provides the necessary whipping. It allows obtaining a product with specified rheological and physicochemical parameters.

ВЛИЯНИЕ ПОРОДЫ КРУПНОГО РОГАТОГО СКОТА НА КАЧЕСТВО СЫРА ДЛЯ ГРИЛЯ

The aim of the work was to conduct a comparative assessment of the quality of grilled cheese (halloumi) obtained from the milk of two different breeds of cows. Cheese was prepared accord-ing to the Cypriot halloumi technology, but instead of sheep or goat milk, cattle milk was used. The milk of the red-mottled breed cows differed from the Simmental milk with a higher content of skimmed milk residue, protein, fat and somatic cells. Grilled cheese using hallumi technology from the milk of both breeds of cows meets the requirements of the state standard R 52686-2006 and is bold (according to the Simmental breed) or fat (according to the red-mottled). Grilled cheese using hallumi technology from red-mottled milk has a 7.2% higher yield, 8.1% less mois-ture, is more saturated with lactic acid, but 1.3 times less dense than cheese from Simmental milk. Grilled cheese according to hallumi technology from milk of both breeds of cows is suitable for frying within 6 days from the moment of manufacture.

Pregnant dairy goats endoparasites reduced by commercial Homeopathy

Background: the endoparasitosis affects dairy goats in worldwide distribution. This impacts the economical activity and implies in eminent risk of animal looses by helminths blood depletion (Nogueira, 2010). Resistance to all therapeutic drugs is reported, the parasitism implies to elevation of production costs, toxic residues in milk and environment, frequently monitoring of ocular mucosa and healthy status (Cavalcanti, 2007; Silva, 2010). Many publications reports Fecal Eggs Count (FEC) FEC reduction in sheeps with homeopathy (Chagas, 2008; Zacharias 2008; Neves, 2012; Falbo, 2013). This work continues the study of previous assessment with young females caprines, but now during the breeding season and multipara pregnants. The under field conditions intends to address the value of this complex medicine in the real life situation of a caprinoculture routine and the animal zootechnical production phases. Aims: this work determined the parasite load by FEC during the periods of breeding season and pregnancy of dairy goats with commercial populational homeopathy. Methodology: Fifteen (15) adult multipara goats (CAPRA AERGICUS HIRCUS) aged 4.4 ± 1.4 years old were randomly enrolled into two groups. The animals has dairy predominance of Alpine and Saanen breeds and were fed by maize and sugar cane silage. Routine measures to reduce the natural parasitism infection included keeping them in elevated houses with slatted floor with access to paddock star grass with time restrictions to the hottest hours in the day. They received the albendazole antihelmintic drenching before each of the phases. The weekly FEC was performed in triplicate with the McMaster Egg Counting Chamber Technique and the optical microscope. The treatment with 10g-animal-day CapriOvi Verm 100 RealH (Brazil) was given daily among both phases, six times a week with individual oral administration, the powder was diluted (not sucussed) in a plastic cup with tap water and given in a 10mL syringe. The control group received only tap water in the same way but brand new separated set of disposable materials. Each phase had evaluating period of 10 and 11 weeks respectively. The first phase has the four weeks breeding season, previously stimulated by light program, with sex mating on the middle and the second phase the animals was pregnant for 2 to 4 months. Results: The FEC kept above 500 eggs during 7 weeks at the breeding season-1st phase but grew as expected in the pregnancy-2nd phase. The FEC was significantly reduced during the 2nd phase (p-value < 0.01) but not in the breeding season-1st phase (p-value = 0.28), despite being lower than the control. The two-way ANOVA showed that treatment in the 2nd phase affected the results [F 1/143 = 9.04, p = 0.0031] as the time does [F 1/143 = 53.29, p < 0.0001]: there were interactions between factors [F 1/143 = 3.15, p = 0.0011]. The two-way ANOVA showed that treatment in the 1nd phase affected the results [F 1/130 = 0.30, p = 0.58] as the time [F 1/130 = 1.24, p = 0.28]: there were no interactions between factors [F 1/130 = 0.58, p = 0.81]. Surprisingly there was absence of growing FEC in the breeding season, at this phase the dry goats and may have better immune response to the endoparasites than the stress of the pregnancy. Our group suppose the stressed animal model is more susceptible and may show better the effects of treatment reducing the FEC in a high challenge situation. How it influences the way of action of ultra high dilutions remains a very interesting question for guide future works. Conclusion: the populational homeopathy product CapriOvi Verm 100 RealH has shown the reduction of the FEC during the pregnancy of dairy goats.

Graphene oxide modified screen-printed electrode for highly sensitive and selective electrochemical detection of ciprofloxacin residues in milk

The monitoring of antibiotic residues in foodstuffs by using rapid detection method is essential for food safety. In this work, the electrochemical sensor was developed by modification of screen-printed carbon electrode with graphene oxide, and then the ciprofloxacin (CIP) was detected based on the complexation of CIP with Mn2+. On modified electrode, the anodic stripping peak current response of Mn2+ was prohibited in the presence of CIP, and a peak current response of the complex was occurred. Thus, the peak current response of the complexation peak was employed as the indicating signal for CIP determination, which was more sensitive than the direct electrochemical oxidation response of CIP. Parameters that affect the signal response have been investigated in method. Under the optimum conditions, the peak current of the complexation peak was linearly correlated with the CIP content in the milk sample solution at 1.0 to 8.0 μM, and the linear correlation coefficients (R2) was 0.994. The limits of detection (LOD) was 0.30 μM. Recoveries of CIP in milk sample were ranged from 81.0 to 95.4% with relative standard deviations (RSDs) below 4.6%. The method showed high selectivity and sensitive, good reproducibility, indicated that this method has potential to be applied in CIP residue analysis.

Migration of Cefquinome Antibiotic Residues from Milk to Dairy Products

The aim of this study was to investigate the distribution of cefquinome in different dairy products during the processing of naturally contaminated milk or spiked milk. The analysis of cefquinome residues in milk, skimmed milk, buttermilk, whey, cream, butter, curd, and cheese samples was performed using a water:acetonitrile solvent extraction and C18 dispersive solid-phase extraction (d-SPE) clean-up, followed by ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS/MS) determination. The target concentration of cefquinome was achieved in the spiked milk (100 µg kg−1). During its processing, the antibiotic migrated primarily with the skimmed milk as opposed to cream (ratios of 3.6:1 and 2.8:1 for experiments A and B, respectively), and with the buttermilk during butter manufacture (ratios of 6.9:1 and 4.6:1), but was equal in the curd and whey during the manufacture of cheese. In the milk collected from treated animals, the measured concentration of cefquinome was considerably high (approx. 5000 µg kg−1). The results obtained from the dairy products were similar to those obtained in the spiked study (ratios of 8.2:1 and 3.1:1 for experiments A and B, respectively, during the separation of skimmed milk and cream; 6.0:1 and 5.0:1 for A and B, respectively, during the separation of buttermilk and butter). However, during cheesemaking, cefquinome migrated with the whey after cutting the curd, with ratios of 0.54:1 and 0.44:1 for experiments A and B, respectively. The difference in the migration of cefquinome between curd and whey in spiked and animal studies is probably due to the different concentration levels in the two different experiments. The results of this study showed that, in dairy products manufactured from milk containing cefquinome residues, the drug migrated primarily with the high-water-containing fractions.

Contamination methods of milk with pesticides residues and veterinary drugs

The use of agricultural pesticides is very important in improving production, but the residue of these pesticides on crops have a serious health effect on humans. On the other hand, there is another type of pollutants resulting from the use of veterinary medicines, as well as heavy metals and mycotoxins that also result in health risks to humans due to their consumption of milk and dairy products. Milk is an important and necessary food for the body as it is consumed daily by many people because its contain fat, protein, vitamin, and minerals. In this work, we present a review of most scientific articles from 1964 until 2020, related to evaluating milk contamination with various chemicals, especially pesticides and veterinary drugs. We observe from many research papers at different country in the world Lingering presence detectable values of chemical contaminate The maximum remainder, as a final result of this review paper we need to establish monitor program system for all chemical contaminate residue in milk and many food type to improve safety and reduce the risk for consumers in Iraq.

English

The mastitis causing microorganisms resist beta-lactam antibiotics by releasing beta-lactamase and the enzyme can be traced in raw milk. This study was aimed at developing a novel platform test to detect beta-lactam antibiotics residues in raw milk based on the Hardy Diagnostic Beta-lactamase Test (HDBT) reagent. The HDBT ingredients modified were penicillin, sodium chloride, trisodium citric acid, trisodium phosphate and phenol red dissolved in distilled water. Pooled raw milk samples were obtained from 3 Friesians and 3 Ayrshires lactating cows identified to have subclinical mastitis and treated using beta-lactam antibiotics. The appropriate mixing ratios were investigated at nine levels. Investigation on the effect of breeds on the test method results was also carried out. Evaluations to determine the colour differences between beta-lactam positive and negative raw milk samples for all the experiments were carried out using trained panelists. The results indicate that gradual addition of trisodium phosphate and phenol red in the reagent showed significant difference (P ≤ 0.05) between a beta-lactam positive and negative raw milk sample. Ratio 5:5 was selected as the best and had significant difference (P ≤ 0.05) from the others. Conversely, the test method indicated no significant difference (P ≤ 0.05) between the Friesians and Ayrshires raw milk samples. This method can be used along the raw milk collection routes to accept, set aside or reject raw milk suspected to have residues. The colour observed for a beta-lactam negative sample was fuchsia purple while peach or pink signified a positive sample.   Key words: Raw milk, antibiotic residues, beta-lactam, beta-lactamase enzyme, trisodium phosphate

The analysis of acidic and basic non-steroidal anti-inflammatory drugs in milk and muscle samples: a comprehensive analytical approach using UHPLC-MS/MS

ABSTRACT In animal husbandry for food production, the administration of non-steroidal anti-inflammatory drugs (NSAIDs) as anti-inflammatory, analgesic, and antipyretic agents, has seen an increase due to raised awareness of animal welfare issues. Residues of NSAIDs may be present in animal products that are intended for human consumption, and since some may pose a certain risk to human health, there is a need to monitor NSAID residues at low levels via routine and targeted surveillance. In analytical chemistry, NSAIDs are usually differentiated using their acid-base properties. Within this study, a method for simultaneous analysis of 27 NSAIDs, including both groups, in milk and muscle samples in 12.5 min is described. Sample processing consisted of enzymatic hydrolysis and acetonitrile extraction, followed by a clean-up of the extract by SPE, and measurement by UHPLC-MS/MS. The in-house validation study (alternative approach), covering trueness, precision, sensitivity, decision limit (CCα), detection capability (CCβ) and matrix effect, was designed and evaluated with the help of validation software to meet the demands of regulatory compliance. The method recovery for milk and muscle matrix was in the range of 98.1% to 106.5% and 98.8% to 102.7%, whereas the CCβ as the parameter for screening analysis, ranged from 0.07 to 46.7 µg/kg and 1.19 to 69.7 µg/kg, and the CCα, as the parameter for confirmatory analysis, from 0.11 to 56.7 µg/kg and 1.12 to 518.6 µg/kg, respectively. The occurrence of NSAID residues in milk and muscle samples was assessed using the developed method within the Croatian National Residue Control Plan, revealing quantifiable residues for diclofenac, ketoprofen, and salicylic acid mostly in milk samples. The most abundant NSAID in analysed samples was salicylic acid, which may be introduced into the food chain and be present in various types of matrices due to its natural occurrence in plants as a phytohormone.

Quantitative determination of targeted and untargeted pesticide residues in coconut milk by liquid chromatography – Atmospheric pressure chemical ionization – high energy collisional dissociation tandem high-resolution mass spectrometry

Quantitative determination of targeted and untargeted pesticide residues from food products is very important for the assessment of safety of the food products. In the present work, a simple, selective and sensitive method based on liquid chromatography atmospheric pressure chemical ionization high energy collisional dissociation high-resolution tandem mass spectrometry (LC-APCI-HCD-HRMS/MS) for quantification of 19 priority organophosphorus and carbamate pesticides and 10 untargeted pesticides from coconut milk samples was developed and validated. The pesticide residues were extracted by solvent partition followed by dispersive solid-phase extraction clean-up and quantified by LC-APCI-HRMS/MS technique. The method showed the linearity for targeted pesticides in the range of 0.5–1000 ng/g with a limit of detection of ranging 0.5–5 ng/g and limit of quantification of ranging 1–10 ng/g measured at 3:1 and 10:1 signal to noise ratios, respectively. The untargeted pesticide residues were quantified by the response factor method. The method was validated for intraday and interday precision, which was less than 15%. The recovery of the analytes varied between 82 and 117%, and the developed method was applied for the analysis of the coconut milk samples. The analyzed samples showed the presence of quinalphos, malathion, and methiocarb at concentrations of 4.55, 5.54, and 206.99 ng/g.

The system of monitoring of inhibitory drug residues in raw cows' milk in Slovakia

This article provides brief information on the system of monitoring raw cows’ milk for the presence of inhibitory veterinary drug residues in the Slovak Republic. We are describing in detail how the monitoring is carried out and what laboratory methods are used for this monitoring. We also deal with the issue of the disposal of contaminated milk. The presence of inhibitory veterinary drugs like antibiotics or residues of these drugs in milk in an amount exceeding maximal residual limits defined in legislation is illegal. Milk supplies containing detectable concentrations are not acceptable. The reputation of milk as a healthy and safe food should be protected. Dairy companies and consequently consumers want to be confident that milk and milk products are free of inhibitory veterinary drugs contamination. Small amounts of certain antimicrobial agents may affect antibiotic resistance in the human population, some percentage of the population is hypersensitive to antibiotics and other drugs. The presence of drug residues in milk affects the technological process of the production of fermented dairy products. Each country should implement a system of monitoring these drugs' residues in food. The system, which is applied in Slovakia, is effective, it can detect and the presence of these substances before milk processing in dairies. The total incidence of these substances in 2020 was 0.025% of all 12,181 samples tested in central testing laboratories. During the last 20 years.

Selection of broad-spectrum aptamer and its application in fabrication of aptasensor for detection of aminoglycoside antibiotics residues in milk

The multi-residues of aminoglycoside antibiotics (AAs) have been reported present in a food product. Taking the broad-spectrum aptamer as recognition element of sensors for simultaneous detection of the class of AAs is of great significance. In this paper, broad-spectrum ssDNA aptamers for AAs with high affinity and specificity were successfully selected by graphene oxide (GO)-SELEX with a group of targets. Further sequence analysis, the truncated aptamer (AAs 03-2) of only 49 nt was observed with higher affinity than original aptamer of 79 nt. The binding mechanism analysis was performed by circular dichroism and molecular docking simulations, which showed the folding structure of aptamer (AAs 03-2) provided binding pockets for AAs and could recognize AAs conserved structure. Subsequently, the affinity of aptamer (AAs 03-2) for other AAs with favorable binding ability was further verified. Finally, the aptamer (AAs 03-2) was used to fabricate electrochemical biosensor based on screen-printed carbon electrode modified by ordered mesoporous carbon for signal amplification. The aptasensor realized simultaneous analysis of AAs with limit of detection of 2.47 nM. Moreover, the proposed aptasensor was successfully applied to evaluate the residual level of AAs in milk, which provides a new method for multi-residues detection of antibiotics.

Notice of correction: The Effect of Boiling on Stability of Oxytetracycline and Sulfamethazine Residues in Raw Milk using HPLC Method

Notice of correction: The Effect of Boiling on Stability of Oxytetracycline and Sulfamethazine Residues in Raw Milk using HPLC Method

Improvement of the computational method for determining the cryoscopic temperature of functional ice cream mixtures

Nowadays the functional ice cream production keeps developing. Due to that the traditional composition of the ice cream is amended. In case of substitution of the low molecular weight nutrients (sucrose, lactose and mineral salts of dry skimmed milk residue) with technologically functional nutrients, it changes the cryoscopic temperature, which influences the parameters of production process, in particular the temperature of the ice cream getting from the freezer. In this regard, the problem of calculating the cryoscopic temperature of ice cream mixtures has become acute, since it is not possible to find this parameter experimentally at all food enterprises. While calculating the cryoscopic temperatures on the basis of existing reference data, in some cases the authors encountered a significant (more than 0.5 °C) deviation of the calculation results from the experimental data. In order to establish the cause of these deviations, the authors analyzed aqueous solutions of sucrose, fructose, trehalose, erythritol, maltodextrin, polydextrose, sorbitol, glucose-fructose syrup, dry glucose syrup, inulin in concentrations that provide for the cryoscopic temperatures of solutions within the range from 0 °C to minus 6 °C. The cryoscopic temperature of the solutions was measured by an osmometer-cryoscope, and the conventional molecular weight of the substances was calculated on the basis of Raoult ratio, taking into account the high molecular weight substances and admixed impurities. It was shown that the values of the conventional molecular weight for trehalose and sorbitol solutions differ by more than 15% from the values of chemically pure substances due to presence of low molecular weight monomers in their composition. The presented experimental data on the conventional molecular weight values can be used for calculation of cryoscopic temperature of various types of mixtures used for ice cream production. As an example of application of obtained clarified values of conventional molecular weights, this article provides a method for calculation of cryoscopic temperature of low sucrose and sucrose-free ice cream mixtures, as well as a comparison of the calculation results with experimentally obtained data.