Milk Powder Samples Research Articles

Comprehensive Analysis of Contaminants in Powdered Milk Samples Using an HPGe for γ Radiation.

Aims: This study aimed to assess the activity concentrations and cancer risk assessments of 232Th and 40K in powdered milk samples collected from various suppliers in Pakistan, considering the increasing concern about cancer risks associated with environmental radiological effects related to food consumption. Subjects and Methods: Specific activity concentrations were determined using a high-resolution, high-purity germanium γ-spectroscopy system. Results: The specific activity levels of 40K and 232Th in the analyzed powdered milk samples were found to be 230.86 and 6.87 Bq/kg, respectively, well within the safe limits recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The hazard index (0.074 Bq/kg) and radium equivalent (27.58 Bq/kg) were calculated as indicators of radiation hazard, along with absorbed dose (26.26 nGy/h), annual effective dose (0.13 nGy/h), and excess lifetime cancer risk (0.45). These parameters provide insights into the potential health risks associated with powdered milk consumption. Conclusions: The findings collectively affirm the radiological safety of the analyzed powdered milk samples, providing valuable insights into the potential health risks associated with their consumption.

A novel electrochemical sensor for the detection of metronidazole residues in food samples

The widespread use and misuse of antibiotics in pharmaceuticals and animal farming has resulted in their accumulation in food sources and the environment, posing significant threats to human health, the environment, and the global economy. In this study, we have developed a hypersensitive, and ultra-selective electrochemical sensor, the first of its kind, by integrating a thermally annealed gold-silver alloy nanoporous matrix (TA-Au-Ag-ANpM) with reduced graphene oxide (r-GO) and poly(glycine) at the surface of a glassy carbon electrode (GCE). This sensor aims to detect life-threatening metronidazole (MTZ) residues in food samples. TA-Au-Ag-ANpM/r-GO/poly(glycine)/GCE was thoroughly characterized using a range of analytical techniques, including UV–Vis, FT-IR, XRD, SEM, and EDX. Furthermore, its electrochemical properties were investigated by cyclic voltammetry (CV), square wave voltammetry (SWV), and electrochemical impedance spectroscopy (EIS). The sensor exhibited outstanding performance, with a broad linear range of 2.0 pM–410 μM. The limits of detection (LOD) and quantification (LOQ) were determined to be 0.0312 pM and 0.104 pM, respectively. The TA-Au-Ag-ANpM/r-GO/poly(glycine)/GCE exhibited exceptional reproducibility, repeatability, stability, and resistance to interferences. Moreover, the sensor demonstrated outstanding performance in detecting MTZ residues in milk powder, pork, and chicken meat samples, achieving very good recoveries (96.9%–101.4%) with a relative standard deviation (RSD) below 5%. This performance highlights the potential for practical applications in food safety and quality monitoring. Therefore, the developed sensor contributes to the advancement of electrochemical sensing technology and its application in ensuring food safety and integrity by combating antibiotic residues.

Sandwich-type electrochemical aptasensor based on hemin-graphite oxide as a signal label and rGO/MWCNTs/chitosan/carbon quantum dot modified electrode for sensitive detection of Acinetobacter baumannii bacteria

Acinetobacter baumannii (A. baumannii) is a pathogenic bacterium that causes severe infections and its rapid and reliable diagnosis is essential for effective control and treatment. In this study, we present an electrochemical aptasensor based on a signal amplification strategy for the detection of A. baumannii, the high specificity and affinity of the aptamer for the target make it favorable for signal amplification. This allows for a highly sensitive and selective detection of the target. The aptasensor is based on a carbon screen-printed electrode (CSPE) that has been modified with a nanocomposite consisting of multi-walled carbon nanotubes (MWCNTs), reduced graphene oxide (rGO), chitosan (CS), and a synthesized carbon quantum dot (CQD) from CS. Additionally, the self-assembled aptamers were immobilized on hemin-graphite oxide (H-GO) as a signal probe.The composition of the nanocomposite (rGO-MWCNT/CS/CQD) provides high conductivity and stability, facilitating the efficient capture of A. baumannii onto the surface of the aptasensor. Also, aptamer immobilized on Hemin-graphite oxide (H-GO/Aptamer) was utilized as an electrochemical signal reporter probe by H reduction. This approach improved the detection sensitivity and the aptamer surface density for detecting A. baumannii. Furthermore, under optimized experimental conditions, the aptasensor was demonstrated to be capable of detecting A. baumannii with a linear range of (10 – 1 × 107 Colony-forming unit (CFU)/mL) and a limit of detection (LOD) of 1 CFU/mL (σ = 3). One of the key features of this aptasensor is its ability to distinguish between live and dead bacteria cells, which is very important and critical for clinical applications. In addition, we have successfully detected A. baumannii bacteria in healthy human serum and skim milk powder samples provided using the prepared electrochemical aptasensor.The functional groups present in the synthetic CQD, rGO-MWCNT, and chitosan facilitate biomolecule immobilization and enhance stability and activity. The fast electron-transfer kinetics and high conductivity of these materials contribute to improved sensitivity and selectivity. Furthermore, The H-GO/Aptamer composite's large surface area increases the number of immobilized secondary aptamers and enables a more stable structure. This large surface area also facilitates more H loading, leading to signal amplification.

Prediction of Milk Powder Raman Spectra and Ammonium Sulfate Adulteration Concentration Based on Neural Network Model

This article aims to explore the changes in Raman spectra of milk powder when different concentrations of ammonium sulfate are adulterated. By conducting neural network tests on milk powder samples with different ammonium sulfate concentrations, we studied the impact of ammonium sulfate adulteration on milk powder. The research results show that moderate concentrations of ammonium sulfate adulteration can improve the solubility and flowability of milk powder, but high concentrations of adulteration may reduce the protein content of milk powder and have negative effects on its sensory quality and safety, causing significant adverse effects on human health. Therefore, the adulteration concentration of ammonium sulfate should be strictly controlled in the production and processing of milk powder to ensure its quality and safety.

Safety and quality assessment of hot-drinks vending machines in Southern Italy

Vending machines (VMs) are common and convenient sources of various food and beverage items. Due to limited available information, concerns have been raised about the hygiene and safety of products dispensed by VMs. This study aims to assess the microbiological contamination of VMs in the Campania region (Italy), by combining microbiological and molecular biology analyses. The results revealed notable microbial contamination in VMs. Total Viable Count exceeded acceptable limits in VMs components, particularly in the inner walls of beverage dispensing nozzles and in the hot-drink product. Coffee and ginseng powders exhibited comparatively lower Total Viable Count values, while chocolate displayed none. Regarding pathogens, Listeria monocytogenes and Salmonella spp. were not detected in any of the samples subjected to analysis. Bacillus cereus (B. cereus) and Staphylococcus aureus (S. aureus) were detected in various VMs components. B. cereus contamination was prevalent, exceeding 80% in some surface swabs (water intake pipe, mixer bowl, and dispensing nozzle), and coincided with a high occurrence in the hot-drink final product. S. aureus was frequently found in milk powder, dispensing nozzles, and cappuccino samples. This research offers valuable insights into VM hygiene and safety, emphasizing the importance of multifaceted approaches to address microbiological contamination and promote public health. Regulatory compliance with cleaning procedures and proactive measures, such as robust self-monitoring plans and adherence to Good Manufacturing Practices, are crucial in mitigating contamination hazards and safeguarding product quality.

Evaluation of essential and trace metals/metalloids distribution and probable human health risk implications from branded liquid and powder milks available in Dhaka City, Bangladesh.

The processed forms of milk, branded liquid, and power milk available in Dhaka city, the capital of Bangladesh, were investigated for essential and trace metal/metalloids regarding nutritional and human health risk aspects. For this, the potential nutritional contribution, estimated daily intake (EDI) and non-carcinogenic risk for six different life stages with male and female categories, as well as the carcinogenic risk for children and adults of both genders, were addressed. In total, 46 branded liquid and powder milk samples were considered for this analysis employing atomic absorption spectroscopy. The concentration of essential elements showed the trends of K > Ca > Na > Mg > Fe > Zn > Mn > Cu and K > Ca > Na > Mg > Fe > Cu > Mn > Zn for liquid and powder milk samples, respectively, but the potentially hazardous one showed the same trends (Cr > Pb > Hg > As > Cd) for both items. Except for Cr, Hg, and Fe, the elemental compositions of both milk categories differed considerably (< 0.05). Compared to the threshold values for milk samples (liquid and powder), Fe (19% and 27%), Mn (100% and 63%), Cu (0% and 23%), Zn (94% and 0%), Pb (25% and 13%), and Cr (0% and 3%) showed above the permissible limits. The nutrient input was the highest for Ca (27.2% and 18.7%), followed by Mg, K, and Na. The EDI of studied elements was within the daily permissible limit in both the milk category (except age group (≤ 3) and the female category). The non-carcinogenic risk assessment showed that the age groups ≤ 3 for liquid milk and ≤ 3 and 3 < X ≤ 14 with female categories for powder milk exceeded the threshold level (> 1) in the case of Cr, Cd, As, Zn, and Mn. The probable carcinogenic risks indicated an unacceptable risk level (< 1.00E-04) for the ingestion of Cr through powder milk samples for children in male and female categories. Finally, it believes that green cow farming practices and green milk processing technology, as well as continuous monitoring of toxic metals, can limit the ultimate risk worldwide.

Rapid authentication of characteristic milk powders by recombinase polymerase amplification assays

The authentication of dairy species has great significance for food safety. This study focused on a more rapid method for identifying major dairy species, and specific recombinase polymerase amplification (RPA)-based assays for cattle, goat, sheep, camel and donkey were developed. Through the developed RPA-based assays, goats and sheep could be simultaneously identified and bovine families could be differentiated. The performances of the RPA assays were validated using 37 milk powder samples, of which 16.2% (6/37) were suspected of being adulterated and 24.3% (9/37) were potentially at risk of being wrongly identified as adulteration. The effectiveness of the developed assays for crude DNA detection was also validated by a rapid nucleic acid extraction kit, and results showed that the presence of large amounts of protein and fat did not affect the qualitative results. Therefore, these assays could combine with the rapid nucleic acids extraction methods for being used in field detection.

Amide and carboxyl dual-functionalized magnetic microporous organic networks for efficient extraction of cephalosporins

Cephalosporins (CEFs) are a class of widely used toxic antibiotics. Development of a rapid and sensitive method for detecting trace CEF residues in food samples is still challenging. Herein, we report preparation of an amide and carboxyl groups dual-functionalized core-shelled magnetic microporous organic network MMON-COOH-2CONH for efficient magnetic solid-phase extraction (MSPE) of CEFs from milk powder samples. Under optimal conditions, the established MMON-COOH-2CONH-MSPE-HPLC-UV method owns wide linear range (3–10000 µg kg−1), low limits of detection (1–3 µg kg−1), large enrichment factors (93.9–99.4), low adsorbent consumption (3 mg), and short extraction time (6 min). Synergistic extraction mechanisms of ionic bonding, hydrogen bonding, π-π, and hydrophobic interactions were elucidated by both theoretical density functional theory calculations and experimental data. This study confirms that preparation of dual-functionalized MMONs and introduction of ionic groups are feasible to promote MMONs application in sample pretreatment.

Processing Practices and Quality of Dairy Products in Burkina Faso

Dairy industry is playing an increasing role in food security and economics of West African countries. However there is a need for more information on the quality and history of the dairy products found on the local markets in order to guide necessary reformations in this sector. The objective of this study was to provide data on the quality and processing practices of dairy products, including some locally manufactured dairy products and imported powder milk commercialised in Burkina Faso. Specifically, a survey was carried out first, to identify the locally manufactured dairy products as well as the manufacturing practices, particularly the malpractices not yet reported in the literature. Then, locally manufactured dairy products (excluding the traditionally fermented milk lait caillé and pasteurised milk), imported powder milk from brands frequently used for processing milk products and fraudulent practices identified during the survey were evaluated through laboratory analyses. Physico-chemical parameters such as pH, acidity and moisture content were determined. In addition microbiological parameters such as aerobic mesophilic flora, yeast and mold, thermotolerant coliforms or enterobactria, were also determined. &#x0D; Results from the survey showed that good manufacturing practices were not strictly observed. In addition it was reported use of salt and a popular street medicine “toupaϊ” (supposedly an antibiotic) for delaying the spoilage/fermentation of the raw milk. Six types of locally manufactured milk products were identified while seven brands of powder milk were frequently used, after repackaging, for processing milk products. Most samples of locally manufactured products were unsatisfactory for fungal and thermotolerant coliforms loads. Powder milk samples showed absence of enterobacteria. Sensory analyses showed that locally manufactured products from powder milk were more appreciated than those made from raw milk. Attempts to reproduce the malpractices of using salt or “toupaϊ” did not lead to significant results compared to the control, suggesting that some respondents did not fully open up about the malpractices. These data are useful since they would give tools to policy makers for quality control and regulation in the sector of dairy products.

Optimizing Milk Safety: Applying Nuclear Techniques in X-ray Fluorescence Spectroscopy for Heavy Metal Quantification in Powdered Milk Consumed in Senegal

This study conducted an elemental analysis and assessed heavy metal concentrations in five powdered milk samples (V1, L1, H1, G1, and D1) from Senegal, utilizing X-ray Fluorescence (XRF). The analysis focused on aluminum (Al), calcium (Ca), potassium (K), phosphorus (P), and chlorine (Cl). Aluminum was either undetected or found at negligible levels in all samples. Calcium levels consistently surpassed the Acceptable Maximum Level (AML) in all samples, with H1 exceeding the AML by approximately 11.1 times (27,745.06 ± 310.16 ppm). Potassium concentrations varied, with G1 exhibiting the highest levels, significantly exceeding the AML (51,058.15 ± 456.13 ppm), while V1 remained within acceptable limits. Chlorine concentrations generally complied with the AML, except for G1, which slightly exceeded the limit (3631.04 ± 31.23 ppm). Phosphorus concentrations in H1 were notably higher than the AML (13,750.94 ± 275.35 ppm). The non-uniformity in heavy metal concentrations among samples emphasizes the need for ongoing research and regulatory scrutiny to address potential risks and ensure the safety of powdered milk.

Target Analysis of Polychlorinated Naphthalenes and Nontarget Screening of Organic Chemicals in Bovine Milk, Infant Formula, and Adult Milk Powder by High-Resolution Mass Spectrometry.

Infant formula is intended as an effective substitute for breast milk but is the main source of polychlorinated naphthalenes (PCNs) to nonbreastfed infants. We performed target and nontarget analyses to determine PCNs and identify other organic contaminants in infant formula. The mean PCN concentrations in infant formula, milk powder, and bovine milk were 106.1, 88.8, and 78.2 μg kg-1 of dry weight, respectively. The PCN congener profiles indicated that thermal processes and raw materials were probably the main sources of PCNs in infant formula. A health risk assessment indicated that PCNs in infant formula do not pose health risks to infants. Using gas chromatography-Orbitrap mass spectrometry, 352, 372, and 161 organic chemicals were identified in the infant formula, milk powder, and bovine milk samples, respectively. Phthalate esters were detected in all four plastic-packed milk powder samples. The results indicated milk becomes more contaminated with organic chemicals during manufacturing, processing, and packaging.

Engineering an Antifouling Electrochemical Sensing Platform Based on an All-in-One Peptide and a Hierarchical β-Bi2O3-Au Microsphere for Vancomycin Detection in Food.

Challenges associated with interference aroused by nonspecific attachment of foulants in the food matrix steered the development of sensor surfaces capable of antifouling capacity. In this study, an antifouling electrochemical sensing platform based on an all-in-one peptide (DOPA3-PPPPEKDQDKKaa) with anchoring, antifouling, and recognition functions and a hierarchical β-Bi2O3-Au microsphere was proposed for vancomycin (Van) detection in food. The β-Bi2O3-Au with excellent conductivity was synthesized and introduced as an electrode modifier to accelerate electron transfer on the sensor surface, enhancing sensing response. Mussel organism-inspired oligo DOPA, that is, oligo 3,4-dihydroxyphenylalanine, was employed as the anchoring segment of the all-in-one peptide, which is versatile for surfaces with different materials. PPPPEKDQDK and Kaa as antifouling and recognition segments confer abilities to resist nonspecific adsorption of foulants and specifically bind Van on the sensor surface, respectively. Notably, the excellent antifouling performance of the proposed sensor has been verified in protein solutions, carbohydrate solutions, and even in diluted milk and honey. Molecular dynamics simulation was carried out to explain the antifouling mechanism of the all-in-one peptide. The proposed sensor can detect Van sensitively and selectively with a relatively wide linear range (0.1-100 ng mL-1) and a limit of detection (LOD) as low as 0.038 ng mL-1 and support the quantification of Van in milk, milk powder, and honey samples with satisfactory recoveries within 105.3-110.8%. This antifouling electrochemical sensing platform offers a feasible strategy to reduce matrix interference, which guarantees the accurate detection of Van in food samples.

Assessment of Aflatoxin M1 in human breast and powdered milk in Tehran, Iran

Aim and backgroundAflatoxins, produced by Aspergillus flavus and Aspergillus parasiticus, are among the most toxic mycotoxins. Aflatoxin M1 (AFM1) is a hydroxylated metabolite of aflatoxin B1 (AFB1), found in milk and dairy products from animals fed AFB1-contaminated feed. Consumption of AFM1 has related adverse effects on human health. Breast milk can be a source of contamination for infants due to the presence of AFM. AFM1 can also contaminate powdered milk, a significant product of the milk industry. Consequently, monitoring dairy products for these toxins is imperative. Study methodA total of 50 samples (25 samples of breast milk and 25 samples of powdered infant milk formula) were collected in Tehran from December 2021 to February 2022. HPLC method was used for the determination of AFM1 in samples. Resultsand Discussion: AFM1 was detected in 72% of breast milk samples and 96% of powdered milk samples. AFM1 levels varied significantly between the two sample types (p < 0.05). The average amount of AFM1 in breast milk samples was 25.82 ± 4.72 ng/kg, while the average amount in powdered milk samples was 40.59 ± 7.76 ng/kg. Moreover, 44% of the breast and 68% of powdered milk samples exceeded the AFM1 content limit of the European Union and the Iranian national standard. This study concludes that given the importance of breast milk and formula to maternal and infant health, monitoring and regulating the toxin levels in these products in Tehran is crucial.

Determination of the fatty and amino acid composition of camel milk, milk powder and shubat

Camel milk is considered an essential source of nutrition and an effective remedy with healing properties in treating several diseases. Shubat, a fermented drink made from camel milk, contains easily digestible proteins, determining its nutritional value. Meanwhile, few studies have analysed the fatty and amino acid composition of Bactrian camel milk, milk powder and shubat in Kazakhstan. In this paper, we used the gas chromatography-mass spectrometry method to determine milk the fatty and amino acid composition of Kazakhstan camel milk and camel milk powder and submit samples. As a result, significant differences in the fatty acid and amino acid compositions were observed among samples of raw milk, milk powder and shubat. differences were found in all amino acids. The most representative fatty acids in the three groups were С16:0, С18:0, С18:1n9c, С14:0 FAs. In camel milk samples, among indispensable amino acids, lysine (29.64%) was the highest in concentration, followed by methionine (25.68%). Some polyunsaturated fatty acids (PUFAs) such as С18:3n3c, С20:4n6, С18:3n3c, С20:3n3c 8,11,14 were found only in shubat samples. Furthermore, we revealed a significant decrease in both dispensable (DAA) and indispensable (IDAA) contents in camel milk powder. Meanwhile, an increase in the quantitative content of amino acids has been observed in shubat, especially in threonine (166.86%), aspargine (156.34%), alanine (114.48%), etc. The results provide a theoretical basis for additional studies of camel milk composition of Bactrian camel in Kazakhstan.

Liquid chromatography-high resolution mass spectrometry analysis of 300 illegally added drugs and their analogues in functional milk powder for the elderly

Various types of milk powder purportedly providing diverse health functions have emerged with the growth of the country's elderly population. Some manufacturers illegally add chemical drugs to their products to achieve their reported benefits, which poses a threat to consumer health. The existing standard methods are inapplicable to such complex sample matrices and require testing based on functional claims and classification. These limitations not only consume manpower and resources but also seriously impede daily regulatory efforts to detect unknown risk substances. In this study, a high-throughput method for the screening and quantitative analysis of 300 illegally added chemical drugs in functional milk powder and an identification strategy for unknown structural analogues were established using Zeno SWATH® data-independent acquisition (DIA) ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) technology combined with a QuEChERS sample purification method. The QuEChERS purification process was developed according to the characteristics of milk powder matrix. The supernatant was separated on a Kinetex F5 column (100 mm×3.0 mm, 2.6 μm) by gradient elution using 5 mmol/L ammonium formate aqueous solution (0.1% (v/v) formic acid, ) and methanol-acetonitrile (1∶1, v/v) as mobile phases. The method was validated in terms of selectivity, linearity, limits of detection and quantification (LODs and LOQs, respectively), matrix effect, accuracy, and precision. Based on a screening database for the 300 target substances, electron-activated dissociation (EAD) fragmentation was applied to obtain rich secondary MS fragmentation information, and unknown structural analogues were identified and confirmed through fragment attribution analysis. The results indicated that all compounds had good linear relationships in certain ranges with correlation coefficients >0.99. The LODs and LOQs were 0.04-2.7 and 0.2-8.0 μg/kg, respectively. The average recoveries at three spiked levels were in the range of 73.1%-125.2%, and the relative standard deviations were ≤14.8% (n=6). When the developed method was applied to detect illegally added chemicals in 60 functional milk powder samples, it detected benzoguanidine and sildenafil and successfully identified ethylphenidate, which is the structural analogue of an amphetamine. The proposed method is simple, sensitive, and accurate; thus, it may have practical application value for the daily supervision and law enforcement of milk powders with reported health functions.

Hyperspectral imaging of foodborne pathogens at colony and cellular levels for rapid identification in dairy products.

This study evaluated the efficacy of hyperspectral imaging (HSI) for the rapid identification of pathogens in dairy products at the colony and cellular levels. The colony and cellular levels studies were designed as completely randomized with six replications. Three strains of Listeria monocytogenes, four strains of Escherichia coli O157: H7, Big Six Shiga toxin-producing E. coli, three strains of Staphylococcus aureus, and ten serovars of Salmonella were used in this study. Pure cultures were streaked for isolation on respective selective media, and hyperspectral data (400-1100 nm wavelength) at the colony and cellular levels were collected and stored as reference libraries. Whole milk and whole milk powder were artificially inoculated (<10 CFU/g or mL) with individual pathogenic strains/serovars. All milk and milk powder samples were enriched using brain heart infusion (BHI) broth at 37°C for 24 h, streaked for isolation on the respective selective media, and hyperspectral data for individual pathogenic strains/serovars at the colony and cellular levels were acquired and treated as test samples data. The acquired colony or cellular images were imported into ENVI software and three regions of interest were selected for each image to obtain hyperspectral data for reference libraries and test samples. Using the kNN classifier and cross-validation technique, overall classification accuracies of 90.38% and 34% were obtained for the colony- and cellular-level identification, respectively. The individual classification accuracies of pathogens in dairy products at the colony level varied between 77.5% to 100%, whereas the accuracy varied between 2.78% and 49.17% for the cellular level.

Impact of Lactation Stage on the Metabolite Composition of Bovine Milk.

Bovine milk is a nutrient-dense food and a major component of the human diet. Therefore, understanding the factors that impact its composition is of great importance. Applications of metabolomics provide in-depth analysis of the metabolite composition of milk. The objective of this research was to examine the impact of lactation stage on bovine milk metabolite levels. Metabolomic analysis of bovine milk powder samples across lactation (N = 18) was performed using nuclear magnetic resonance (1H-NMR) spectroscopy and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Forty-one metabolites were identified and quantified in the 1H-NMR spectra. Statistical analysis revealed that 17 metabolites were significantly different across lactation stages (FDR < 0.05), of which the majority had higher levels in early lactation. In total, 491 metabolites were measured using LC-MS/MS, of which 269 had significantly different levels across lactation (FDR < 0.05). Compound classes significantly affected by lactation stage included phosphatidylcholines (59%) and triglycerides (64%), of which 100% of phosphatidylcholines and 61% of triglycerides increased from early lactation onwards. Our study demonstrates significant differences in metabolites across the stages of lactation, with early-lactation milk having a distinct metabolomic profile. More research is warranted to further explore these compositional differences to inform animal feeding practice.

Electrochemical determination of ethylvanillin based on LaV@GAC nanocomposite.

Ethyl vanillin (EVA) is widely used as a flavor additive in foods, and sensitive monitoring of EVA is of great significance for food safety. In this paper, the biomass of gum arabic derived carbon (GAC) coated with lanthanum vanadate (LaV) was constructed for the EVA sensor based on the synergistic effects of the electrochemical catalytic ability of LaV, the enhanced electrical conductivity with the GAC coating and the oxygen-containing functional groups in LaV@GAC. The as-developed LaV@GAC sensor showed a remarkable linear range from 0.06μM to 100μM and a low detection limit (LOD) of 6.28nM. The electrochemical oxidation of EVA is limited by a diffusion-controlled process involving 2 electrons and 2 protons. Moreover, the LaV@GAC sensor has good recoveries (94.5-103.05%) for the detection of EVA in real milk powder samples. The proposed LaV@GAC sensor has good repeatability, high stability, and great potential for sensitive detection of flavor additives in food.

Identification of the animal origin of milk via Laser-Induced Breakdown Spectroscopy

The identification of milk's animal origin is traditionally performed by chemical/biochemical techniques. More recently, modern spectroscopic techniques are emerging as more suitable tools for this task. In the present work, Laser Induced Breakdown Spectroscopy (LIBS) assisted by machine learning is proposed for the identification of milk animal origin (cow, goat, sheep). For that purpose, 1296 raw liquid milk samples, and 683 lyophilized powdered samples, were studied by LIBS, and the corresponding spectra were analyzed by different machine learning algorithms in view of their classification based on the animal origin. Furthermore, to reduce the spectroscopic data volume, few spectral features related to milk's mineral content were selected and used for the classification of the milk samples. In all cases, predictive models were constructed and evaluated, and the corresponding predictive accuracies were calculated using unknown milk samples. The achieved predictive accuracies using the entire LIBS spectra attained values as high as 92.8 and 95.5% for the liquid and lyophilized powder milk samples, respectively, while using only five spectral lines related to the inorganic content of milk (Mg, Ca, Na, and K), classification accuracies up to 87.6 and 92.9% were obtained for the liquid and lyophilized powder milk samples, respectively. The present findings demonstrate the great potential of LIBS for discriminating milk samples based on animal origin.

Quality evaluation and microbial enumeration of plant based probiotic yoghurt from powdered milk and tiger nut milk

Some commercial yoghurt manufacturers have promoted the usage of artificial thickening and binding agents in the production of yoghurt. These substances, most of which are chemically synthesized could be dangerous. The purpose of this research is to assess the physicochemical characteristics of yogurt made from full cream milk, skimmed milk, and tiger nut milk. It also aimed to estimate the total aerobic plate count, total coliform count, and total mold count of the products for microbiological analyses. The powdered milk samples were reconstituted into liquid and the sorted-clean tiger nut was blended in order to extract the milk. Tiger nut milk proportion of 20 to 30 % was incorporated into the liquid milk before fermentation. The harvested yoghurt was assayed for sensory, physicochemical and microbial analyses. The result obtained showed a level of significant difference (p &lt; 0.05). Among the samples produced, sample G has the least acceptable value 5.00 while sample C had the highest acceptable value 7.05 across the sensory scores. The values obtained from the physicochemical analysis showed that pH value ranged from 3.67 to 4.97. For TDS and titratable acidity (TA), the values ranged from 4.53 to 6.72 x 102 ppm and 0.62 to 0.87 respectively. None of the yoghurt samples had coliform growth on the medium after the incubation period while total viable count ranged from 78.67 to 227.33 cfu/ml and total mould count ranged from 16.67 to 56.67 sfu/ml at a dilution factor of 102. Tiger nut milk can be used in the production of yoghurt as a possible substitute because of its nutritional content and health advantages. Therefore, it is imperative to assert that the use of tiger nut milk in the manufacturing of yoghurt will improve the quality of yoghurt and ultimately result in a desired product.