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The quality of Protected Designation of Origin (PDO) Fiore Sardo, an Italian cheese, is investigated by Time-Domain Nuclear Magnetic Resonance (TD-NMR) relaxometry. In this work, artisanal and industrial products are analysed in terms of relaxometric parameters to describe their quality. Artisanal cheeses were produced from raw milk (RC) by five shepherds, as indicated by following the official protocol. Heat-treated milk cheeses (HTC) counterparts were produced with the same manufacturing process. Commercial industrial cheeses (IND) were also analysed and compared to RC and HTC. TD-NMR relaxometry parameters are able to describe Fiore Sardo quality (RC, HTC and IND cheeses). The characteristic variability of artisanal productions is properly highlighted, and the influence of milk heat treatment and industrial processing is clearly observable in HTC and industrial cheeses as highlighted by TD-NMR relaxometry parameters. TD-NMR relaxometry can potentially be exploited in quality-control practices in the dairy sector, as a valid alternative to more sophisticated analytical techniques. [ABSTRACT FROM AUTHOR]

The study was conducted to estimate the quantity of the products of Maillard reactions and nitrogenous substances in milk samples heat-treated at different temperatures because of their great importance in determining the intensity of heat treatments that milk was exposed to and the extent of their impact On its nutritional value and the detection of the type of milk used by preparing 3 samples of raw milk and 3 samples of recycled dried milk, and treating them at different temperatures (63 °C/30 minutes, 73° C/15 seconds and 115 °C/15 minutes) and four samples of milk Ultra heat treated with were collected from the local Iraqi markets, by estimating the amount of Furosine, HMF, the percentage of total nitrogen, non-protein nitrogen and real protein. The quantity of Furosine on the first day of storage was between 4.09 - 283.15 mg/100 g protein in the milk samples. Laboratory heat and between 104.09 - 189.76 mg/100g protein in UHT milk samples and increased during storage to reach at the end of storage period between 4.13 - 286.76 mg/100g protein in laboratory heat-treated milk samples and between 144.71 - 238.72 mg/100g protein in samples UHT milk, as for HMF, its concentration on the first day of storage reached between 2.06 - 35.37 ìmol/L in laboratory heat-treated milk samples and between 4.28-33.06 ìmol/L in UHT milk and increased to reach at the end of the storage period between 2.22 - 35.76 ìmol/L in laboratory heat-treated milk samples and between 4.91 - 34.57 ìmol/L in UHT milk samples. The values of true protein and non-protein nitrogen were evaluated on the first day of laboratory heat-treated milk samples between 3.45 - 3.47, 3.03 - 3.22, 0.25 - 0.43% and in UHT milk between 3.03 - 3.32, 2.64 - 3, and 0.31 - 0.39% for each of them, respectively. The values of real protein and non-protein nitrogen increased and the values of real protein, real protein and non-protein nitrogen in milk samples thermally decreased at the end of the storage period between 3.43 - 3.49 and 2.71 - 2.91 and 0.58 - 0.71% and in UHT milk between 2.87 - 3.22 and 2.32 - 2.71 and 0.51 - 0.55% each, respectively. [ABSTRACT FROM AUTHOR]

The aim of our study was to establish whether heat treatment and souring of milk affect its estrone (E1) and 17β-estradiol (E2) concentrations. Milk samples were collected from 10 Holstein cows in late pregnancy. Concentrations of E1 and E2 were measured in milk samples that were previously heated to 70 and 95°C for 5 min. Additionally, E1 and E2 concentrations were determined in the same milk samples after 2 d of spontaneous souring at room temperature, and these samples were compared with E1 and E2 levels in raw, unprocessed milk. Concentrations of both hormones were determined by commercial ELISA kits. Concentrations of E1 in unprocessed and processed milk (milk heated to 70 and 95°C and soured milk) were (mean ± SE) 47.25 ± 4.16, 44.84 ± 3.47, 41.00 ± 4.55, and 44.92 ± 3.91 pg/mL, respectively. Concentrations of E2 in the same milk samples were 36.11 ± 10.01, 32.46 ± 9.88, 31.78 ± 9.56, and 31.43 ± 8.00 pg/mL, respectively. Concentrations of E1 and E2 in heat-treated milk did not differ significantly from those in unprocessed milk. Similarly, E1 and E2 concentrations in soured milk did not differ significantly from those in unprocessed milk samples. These results indicate that E1 and E2 are stable in milk and that milk processing (heating and souring) does not influence their degradation. Therefore, E1 and E2 concentrations are expected to be similar between commercial full-fat milk and the raw milk from which it was produced. [ABSTRACT FROM AUTHOR]

Bacillus cereus widely distributed in the environment and can survive all types of heat treatment so, The present study was undertaken to assess the presence of Bacillus cereus in 60 milk samples (boiled milk, pasteurized milk and ultra-heat milk "UHT") (20 each) were collected randomly from different dairy shops and supermarkets in Kafr El-Sheikh governorate. The results revealed that the incidence of B. cereus was 50%, 15% and 15%from boiled milk, pasteurized milk and ultra-heat milk (UHT), respectively. Susceptibility of B. cereus isolates to 14 antimicrobial agents showed that B. cereus isolates were high sensitive to Ciprofloxacin (Cp) 87.5%, Gentamicin 81.2%, Enrofloxacin (En) 62.5, Norfloxacin (NoR) 50%, Erythromycin (E) 43.8%, followed by Cephalothin (CN) 25%, Ampicillin (Am) 31.2%, Chloramphenicol (C), 18.8%, Cefixime (CF) 12.5%, Streptomycin (S 12.5%. Finally Oxytetracycline (T) 6.3%, while the isolates showed the highest resistance against Neomycin (N) 100%, followed by Kanamycin (K) 93.7% and finally Sulphamethoxazol (SXT) 81.2%. Detection of virulence genes of 16 isolates of B. cereus by multiplex PCR indicates that only 4 isolates (25%) were positive for hbl C gene, 2 isolates (12.5%) for cyt K gene and 10 isolates (62.5%) were positive for both hbl C and cyt K genes. Our data showed that the occurrence of the gene sequences that code for enterotoxins production increases the virulence and the public health hazard of these bacteria. [ABSTRACT FROM AUTHOR]

Consumers have recently shown a preference for natural food products and ingredients and within that framework, their interest in consuming raw drinking milk has been highlighted, claiming nutritional, organoleptic and health benefits. However, a public debate has simultaneously emerged about the actual risks and benefits of direct human consumption of raw milk. This paper compares the microbiological, nutritional and sensory profile of raw and heat-treated milk, to evaluate the real risks and benefits of its consumption. In detail, it provides an updated overview of the main microbiological risks of raw milk consumption, especially related to the presence of pathogens and the main outputs of risk assessment models are reported. After introducing the key aspects of most commonly used milk heat-treatments, the paper also discusses the effects such technologies have on the microbiological, nutritional and sensory profile of milk. An insight into the scientific evidence behind the claimed protective effects of raw milk consumption in lactose-intolerant subjects and against the onset of asthma and allergy disorders in children is provided. The emergence of novel milk processing technologies, such as ohmic heating, microwave heating, high pressure processing, pulsed electric fields, ultrasound and microfiltration is also presented as an alternative to common thermal treatments.

Aflatoxin M1 in milk and dairy products represents a concern for food safety, and laboratories involved in its determination have to use reliable and robust test methods. to this purpose, both method validation and participation in proficiency studies are mandatory requirements for demonstrating adequate technical competence. In this work, the validation of a HPLc method for determination of aflatoxin M1 (AFM1) in milk, through both proficiency testing and intra-laboratory study, according to the UNI CEI EN ISO/IEC 17025 standard is described. A survey about AFM1 levels in both raw and heat-treated milk from southern Italy over the years 2002-2005 is also reported. A total of 552 samples from cows, buffaloes, sheep and goats were analysed; AFM1 was detected in 248 samples (44.9%), from all the species. Most of these samples contained AFM1 concentrations that were well below the legal maximum residue limit (MrL); only 33 samples were non-compliant (6.0%); bovine milk was the most contaminated. Moreover, the first long-term survey regarding contamination of raw buffalo milk is described and discussed. The highest contamination levels were detected in 2003 and 2005. [ABSTRACT FROM AUTHOR]

Thermal treatments induce variable physical and chemical modifications in milk molecules, which determine the quality of dairy products. Discrimination of the samples involved in different degrees of heat treatment can be used to direct further ingredient formulations and target products. A new approach was developed to discriminate the degree of heat treatment applied to milk using infrared absorption profile coupled with chemometric measurements. Samples were submitted to different heating procedures that combined various times and temperatures. Infrared absorption spectra of the samples were obtained without any preparation. Principal component analysis was employed to extract characteristic absorption wavelengths of heat-treated milk by modeling the raw data of the absorption profiles after the samples underwent various heat treatments. The accuracy of the random forest model was as high as 0.97, which confirmed as the best performance classifier compared with support vector machine, k -nearest neighbor and linear discriminant analysis. Thus, the present method, which globally exhibits the structural or chemical changes in heat-treated milk by means of IR measurements, could be a comprehensive and accurate approach for heat treatment indicators. • A promising tool based on FTIR was developed for heated milk authentication. • RF model was indicated as the best performance classifier. • Structural or chemical changes of the heat-treated milk were globally exhibited. [ABSTRACT FROM AUTHOR]