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1.
The aim of this article was to present the studies of radiological level of some commercial dairy products in Mazovian, Kuyavian—Pomeranian and Lublin regions. They were carried out for 27 commercial dairy products such as two specimens of lean cottage cheese, three specimens of cottage cheese containing a limited percentage of fat, three specimens of fat cottage cheese, three specimens of milk containing 3.2% of fat, three specimens of milk containing 2.0% of fat, two specimens of sour cream containing 12% of fat, three specimens of sour cream containing 18% of fat, one specimen of 30% whipping cream, two specimens of homogenized (strawberry and vanilla) cheese, three specimens of hard rennet cheese, one specimen of powdered milk, one specimen of goat milk. For the given commercial dairy products there were calculated effective doses (μSv) obtained after consumption of 1 kg contaminated product for different age groups.  相似文献   

2.
In this study, the encapsulation of saffron extract (SE) was examined at four various concentrations of soy lecithin (0.5%–4% w/v) and constant concentration of SE (0.25% w/v). Particle size and zeta potential of liposomes were in the range of 155.9–208.1 nm and −34.6–43.4 mV, respectively. Encapsulation efficiency was in the range of 50.73%–67.02%, with the stability of nanoliposomes in all treatments being >90%. Encapsulated SE (2% lecithin) was added to ricotta cheese at different concentrations (0%, 0.125%, 1%, and 2% w/v), and physicochemical and textural properties of the cheese were examined. Lecithin concentration significantly (p ≤ 0.05) affected the particle size, zeta potential, stability, and encapsulation efficiency of the manufactured liposomes. In terms of chemical composition and color of the functional cheese, the highest difference was observed between the control cheese and the cheese enriched with 2% liposomal encapsulated SE. Hardness and chewiness increased significantly (p ≤ 0.05) in the cheeses containing encapsulated SE compared to the control cheese. However, there was no significant difference in the case of adhesiveness, cohesiveness, and gumminess among different cheeses. Overall, based on the findings of this research, liposomal encapsulation was an efficient method for the delivery of SE in ricotta cheese as a novel functional food.  相似文献   

3.
The stability of milk proteins is affected by changes in the pH value of milk, the heating temperature, and the addition of calcium compounds or chelating agents, which can cause alterations in calcium distribution. The purpose of this study was to determine the potential of the use of calcium citrate to manufacture fresh acid rennet cheese from high-temperature-pasteurized goat’s milk (90 °C, 15 s) from the spring and autumn season and the effect of the calcium dose used on the physicochemical and organoleptic properties of the cheese. Autumn milk was found to be a richer source of total solids, confirming the effect of the production season on milk quality. The applied doses of calcium did not cause the denaturation of goat milk proteins and allowed pasteurization to take place at 90 °C for 15 s. The addition of calcium citrate resulted in a significant increase in the pH value of milk and cheese compared to the control sample. Adding 15 and 20 mg of Ca 100 g−1 to milk as citrate had the most beneficial effect on increasing protein retention in cheese in both seasons, showing a rise from 1.33% to 2.40%. The production season significantly influenced the cheese yield. The control goat cheese from the autumn season showed a 6.85% higher yield compared to the spring cheese. An increase in cheese yield was also observed as the calcium dose of milk increased. The content of micro- and microelements in cheese was affected by the production season. The addition of calcium citrate to milk resulted in a significant increase in the calcium content of cheese—from 120.83 to 147.45 mg 100 g−1 in the spring season and from 130.66 to 151.21 mg 100 g−1 in the autumn season. Increasing the dose of calcium increased the hardness of cheese samples by 1.37 N in the spring and 0.90 N in the autumn. The organoleptic evaluation showed that adding calcium to milk did not significantly affect the organoleptic characteristics of goat cheese.  相似文献   

4.
Summary Transfer of 226Ra, 85Sr and 137Cs from cow and sheep milk to various Syrian dairy products has been evaluated. Dairy products include Kashkivan cheese, braided cheese, Haloom cheese, Sircassian cheese, liquid cheese, native cheese, cottage, thick yogurt, butter and milk cream. The results showed that the percentage of 226Ra, 85Sr and 137Cs transferred from cow milk to milk cream (Pt=food processing retention factor′processing efficiency′100%) has reached 32%, 16% and 7%, respectively. Butter and liquid cheese were found to have the lowest percentage of transferred 226Ra, 85Sr and 137Cs. Most of the obtained Pt values of the studied radionuclides in thick yogurt were relatively low in spite of the high processing efficiencies of thick yogurt. Moreover, the transfer, Pt, of the studied radionuclides from cow milk to the prepared cheese was higher than those values determined for sheep milk. This is due to differences in chemical compositions of each type of milk. On the other hand, the treatment of Native cheese, most commonly consumed cheese in Syria, with different concentrations of NaCl solutions showed that 137Cs was completely removed from cheese soaking in 5% NaCl solution (soaking time of 48 hours), while 40% of 226Ra and 80% of 85Sr were also decontaminated using 0-2.5% NaCl solutions and soaking time of 48 hours. Based on the obtained results, industrialization processes of the dairy products that resulted the removal of radionuclides have been identified.</p> </p>  相似文献   

5.
Zinc is an essential mineral which plays a key role in several important biological processes in the human body. The determination of its level in food matrices can contribute to the food quality characterization and to the adequacy of the diet. Animal food products generally have a higher zinc content compared to vegetables. Among them, dairy products consumption can provide a great contribution to the zinc reference intakes. In this study, different Italian cheeses (38 Protected Denomination of Origin and 9 Traditional) were evaluated for their zinc content. Cow cheeses generally showed the highest zinc content (1.83–7.75 mg/100 g cheese), followed by sheep cheeses (1.34–3.69 mg/100 g), and cheeses from mixed milk (0.39–4.54 mg/100 g). The only cheese from buffalo milk (Mozzarella di Bufala Campana PDO) showed a zinc content of 2.14 mg/100 g. The great variability in the zinc content observed among the samples is the result of the influence of several factors, such as the feeding system, the species (cow, sheep, goat, and buffalo), and the cheese-making. Most of the samples resulted in a great contribution (>10%) to the zinc Daily Reference Intake set by EU (10 mg/day), with only two samples contributing to less than 4%.  相似文献   

6.
Pickering emulsions, which are emulsions stabilized by colloidal particles, are being increasingly positioned as novel strategies to develop innovative food product solutions. In this context, the present work aims to develop Pickering emulsions stabilized by natural-based curcumin-loaded particles produced by the solid dispersion technique as promising mayonnaise-like food sauce alternatives. Two particle formulations (KC1 and KC2) were produced using k-carrageenan as the matrix material and different curcumin contents, then employed in the preparation of three Pickering emulsion formulations comprising different oil fractions (φ) and particle concentrations (KC1 φ 0.4 (4.7%), KC2 φ 0.4 (4.7%) and KC2 φ 0.6 (4.0%)). The creaming index tests accompanied by the optical microscopy analysis evidenced the good stability of the developed products for the tested period of 28 days. The final products were tested concerning color attributes, pH, oxidative stability, textural, and nutritional composition, and compared with two commercial mayonnaises (traditional and light products). Overall, the produced emulsions were characterized by a bright yellow color (an appealing attribute for consumers), an acidic pH (similar to mayonnaise), and a considerably improved oxidative stability, implying a foreseeable longer shelf life. The sauce KC1 φ 0.4 (4.7%) showed a similar texture to the light commercial mayonnaise, being a promising alternative to conventional sauces, holding a low-fat content and potentially added benefits due to the curcumin and virgin olive oil intrinsic properties.  相似文献   

7.
In this research effects of heat treatment duration on the electrical properties (zeta potential and conductivity), texture and color of polymerized whey protein (PWP) were analyzed. Whey protein solutions were heated for 30 min to obtain single-heated polymerized whey protein (SPWP). After cooling to room temperature, the process was repeated to obtain double-heated polymerized whey protein (DPWP). The largest agglomeration was demonstrated after 10 min of single-heating (zeta potential recorded as −13.3 mV). Single-heating decreased conductivity by 68% and the next heating cycle by 54%. As the heating time increased, there was a significant increase in the firmness of the heated solutions. Zeta potential of the polymerized whey protein correlated with firmness, consistency, and index of viscosity, the latter of which was higher when the zeta potential (r = 0.544) and particle size (r = 0.567) increased. However, there was no correlation between zeta potential and color. This research has implications for future use of PWP in the dairy industry to improve the syneretic, textural, and sensory properties of dairy products.  相似文献   

8.
Iron–manganese silicate (IMS) was synthesized by chemical coprecipitation and used as a catalyst for ozonating acrylic acid (AA) in semicontinuous flow mode. The Fe-O-Mn bond, Fe-Si, and Mn-Si binary oxide were formed in IMS on the basis of the results of XRD, FTIR, and XPS analysis. The removal efficiency of AA was highest in the IMS catalytic ozonation processes (98.9% in 15 min) compared with ozonation alone (62.7%), iron silicate (IS) catalytic ozonation (95.6%), and manganese silicate catalytic ozonation (94.8%). Meanwhile, the removal efficiencies of total organic carbon (TOC) were also improved in the IMS catalytic ozonation processes. The IMS showed high stability and ozone utilization. Additionally, H2O2 was formed in the process of IMS catalytic ozonation. Electron paramagnetic resonance (EPR) analysis and radical scavenger experiments confirmed that hydroxyl radicals (•OH) were the dominant oxidants. Cl, HCO3, PO43−, Ca2+, and Mg2+ in aqueous solution could adversely affect AA degradation. In the IMS catalytic ozonation of AA, the surface hydroxyl groups and Lewis acid sites played an important role.  相似文献   

9.
Saffron is a spice obtained from the drying process of the stigmas of the flower Crocus sativus Linnaeus. It is well known that the organoleptic characteristics of this spice are closely linked to the production area and harvesting year. The present work aims to evaluate whether saffron samples produced in different years and origins present sensibly different crocin profiles. To achieve this goal, 120 saffron samples were harvested between 2016 and 2020 in four different Italian areas. The crocins were analysed, identified, and quantified by high-performance liquid chromatography–electrospray–tandem mass spectrometry (HPLC–ESI–MS/MS) in multiple reaction monitoring mode (MRM). Subsequently, ANOVA–simultaneous component analysis (ASCA) was used to evaluate whether the origin and annuity significantly affected the composition of the crocins. ASCA confirmed the relevance of these effects. Eventually, soft independent modelling by class analogy (SIMCA) models were created for each of the four different origins. Mixtures of saffron from different areas were also prepared to test the robustness of the models. SIMCA provided satisfying results; in fact, models provided 100% sensitivity for three origins (Cascia, Sardinia, and Città della Pieve) on the external test set (48 samples) and 88% (sensitivity on the external test set) for the Spoleto class.  相似文献   

10.
Molecular sensors able to detect ions are of interest due to their potential application in areas such as pollutant sequestration. Alkynylplatinum(II) terpyridine complexes with an amide-based receptor moiety have been synthesized and characterized. Their anion binding properties based on host–guest interactions have been examined with the use of UV-vis absorption and emission spectral titration studies. Spectral changes were observed for both complexes upon the addition of spherical and nonspherical anions. Their titration profiles were shown to be in good agreement with theoretical results predicting a 1:1 binding model, and the binding constants were determined from the experimental data. Drastic color changes from yellow to orange–red were observed for one of the complexes upon titration with fluoride (F) ion in acetone. These changes were ascribed to the deprotonation of the amide functionalities induced by F ion, and this was confirmed by the restoration of spectral changes upon addition of trifluoroacetic acid to the F ion–complex mixture as well as by electrospray ionization mass spectrometry (ESI-MS) data.  相似文献   

11.
Manure is a major source of soil and plant contamination with veterinary drugs residues. The aim of this study was to evaluate the uptake of 14 veterinary pharmaceuticals by parsley from soil fertilized with manure. Pharmaceutical content was determined in roots and leaves. Liquid chromatography coupled with tandem mass spectrometry was used for targeted analysis. Screening analysis was performed to identify transformation products in the parsley tissues. A solid-liquid extraction procedure was developed combined with solid-phase extraction, providing recoveries of 61.9–97.1% for leaves and 51.7–95.6% for roots. Four analytes were detected in parsley: enrofloxacin, tylosin, sulfamethoxazole, and doxycycline. Enrofloxacin was detected at the highest concentrations (13.4–26.3 ng g−1). Doxycycline accumulated mainly in the roots, tylosin in the leaves, and sulfamethoxazole was found in both tissues. 14 transformation products were identified and their distribution were determined. This study provides important data on the uptake and transformation of pharmaceuticals in plant tissues.  相似文献   

12.
An ultra-high performance liquid chromatography tandem mass spectrometry method was developed and validated for the sensitive determination and unambiguous confirmation of residues of per and polyfluorinated alkyl substances (PFAS) in breastmilk, retail milk and infant formulas following two sample preparation methods. Sample pre-treatment was carried out by a simplified QuEChERS method without requiring dSPE or any further clean-up. The method was validated in accordance with the requirements of Commission Decision 657/2002/EC with slight modifications. The method displayed good linearity with R2 ranging from 0.9843–0.9998 for all target PFAS. The recovery and within-laboratory reproducibility of the method (n = 63) were in the range 60–121% and 5–28%, respectively. The decision limit, detection capability and limit of quantitation ranged from 30–60 ng kg−1 to 40–100 ng kg−1 and 5–50 ng kg−1, respectively. Acceptable matrix effect values in the range −45–29% were obtained with uncertainty of measurement lower than 25% for all target PFAS. The method displays its suitability for the sensitive and high-throughput confirmatory analysis of C4–C14 PFAS in breastmilk, dairy milk and infant formulas.  相似文献   

13.
Deoxynivalenol (DON) is one of the most common mycotoxins in grains, causing gastrointestinal inflammation, neurotoxicity, hepatotoxicity and embryotoxicity, even at a low quantity. In this study, a facile electrochemical aptasensor was established for the rapid and sensitive determination of DON based on a multifunctional N-doped Cu-metallic organic framework (N–Cu–MOF) nanomaterial. The N–Cu–MOF, with a large specific surface area and good electrical conductivity, served not only as an optimal electrical signal probe but also as an effective supporting substrate for stabilizing aptamers through the interactions of amino (-NH2) and copper. Under the optimal conditions, the proposed sensor provided a wide linear concentration range of 0.02–20 ng mL−1 (R2 = 0.994), showing high sensitivity, with a lower detection limit of 0.008 ng mL−1, and good selectivity. The sensor’s effectiveness was also verified in real spiked wheat samples with satisfactory recoveries of 95.6–105.9%. The current work provides a flexible approach for the rapid and sensitive analysis of highly toxic DON in food samples and may also be easily extended to detect other hazardous substances with alternative target-recognition aptamers.  相似文献   

14.
This research developed model foods of gelatine-based gels, where carbohydrates from Agave tequilana Weber var. Azul (agave syrups or/and agave fructans) were incorporated into gel formulations as healthy sucrose and glucose substitutes. The sugars (sucrose and glucose) were substituted by agave carbohydrates (agave syrups and agave fructans), obtaining the subsequent gel formulations: 100% agave syrup (F2 gel), 100% agave fructan (F3 gel), and 50% agave syrup–50% agave fructan (F4 gel). The unsubstituted gel formulation was used as a control (F1 gel). The prebiotic activities, physical properties, thermal stability (HP-TLC), and texture of gelatine-based gels were evaluated. The gel formulations showed translucent appearances with approximately 36 g/100 g of water and water activities values between 0.823 and 0.929. The HP-TLC analysis validated that agave fructans did not hydrolyse during the thermal process of gels production. Gels produced with agave syrup and agave fructan (F2-F4 gels) provided higher hardness, gumminess, and springiness values (p < 0.05) than those produced with glucose and sucrose (F1 gel). Gelatine-based gel formulations displayed prebiotic activities correlated to the ability of Lactobacillus plantarum, Lactobacillus paracasei, and Lactobacillus rhamnosus to use agave carbohydrates as carbon sources. Based on the prebiotic effect and physical and textural properties, the F2 and F4 gel formulations displayed the best techno-functional properties to produce gel soft candies.  相似文献   

15.
The color stability of anthocyanins (ACN) has been shown to be improved by interaction with whey proteins (WP). In this study, we explore the ACN–WP interaction using Fourier transform infrared spectroscopy (IR). ACN from purple corn, grape, and black carrot (50 μM) were evaluated. IR spectra (4000–700 cm−1) were collected for native and preheated (40–80 °C) WP (5 mg/mL) and ACN–WP mixtures at pH 7.4. Soft independent modeling of class analogy was used to analyze the IR data. The WP secondary structure changed after heat treatments and after interaction with ACN. As expected, the WP α-helices decreased, and β-sheet increased after heat treatment. The intensities of the WP amide I and II bands decreased after ACN addition, revealing a decrease in the WP α-helix content. Higher preheating temperatures (70–80 °C) resulted in a more disordered WP structure that favored stronger WP–ACN interactions related to amide III changes. Addition of ACN stabilized WP structure due to heat denaturation, but different ACN structures had different binding affinities with WP. WP structure had less change after interaction with ACN with simpler structures. These results increase our understanding of ACN–WP interactions, providing a potential strategy to extend anthocyanin color stability by WP addition.  相似文献   

16.
The aim of this study was to determine the effect of adding calcium compounds to processed goat’s milk, and on the properties of acid rennet goat’s milk gels, which are a middle product obtained in the manufacture of acid rennet cheese. The properties of the gels directly affect the quality of acid rennet cheeses. The analysis of raw goat’s milk was carried out, then acid rennet gels were produced with the addition of six different calcium compounds (chloride, citrate, bisglycinate, gluconate, lactate, and carbonate). The dynamics of milk fermentation were performed by monitoring the pH value of milk during acidification. The pH, syneresis, color, and texture profile were determined in the formulated acid rennet gels. An organoleptic evaluation was also performed. The study demonstrated that, not only calcium chloride, but also calcium citrate, gluconate, lactate, bisglycinate, and calcium carbonate could be used in the production of goat’s milk acid rennet gels, or the middle product in the manufacture of acid rennet curd cheese from goat’s milk. Notably, the addition of citrate, bisglycinate, and calcium carbonate in doses of 20 mg Ca 100 g−1 most effectively reduced syneresis compared to the control sample by 4.76% (citrate), 7.85% (bisglycinate), and 10.28% (carbonate). The hardness of the control gels ranged from 2.35 N to 2.99 N. The addition of chloride, citrate, gluconate, lactate, and calcium carbonate to the milk improved the acid rennet gel’s hardness. The addition of 20 mg Ca 100 g−1 as gluconate increased the hardness the most (3.61 N). When increasing the calcium dosage in the form of all compounds, there was a tendency to increase the gel’s springiness. The addition of chloride, citrate, and bisglycinate to milk did not result in a darkening of the gel’s color. The addition of calcium compounds mostly reduced the intensity of goatish taste and odor. Calcium gluconate, in particular, reduced the goatish taste the most, a taste which is not always acceptable by the consumers.  相似文献   

17.
Low-density lipoprotein (LDL) is a cardiac biomarker identified in the pathology of cardiovascular disease (CVD). Typically, the level of LDL is calculated using the Friedewald relationship based on measured values of total cholesterol, high-density lipoproteins (HDL), and triglycerides. Unfortunately, this approach leads to some errors in calculation. Therefore, direct methods that can be used for fast and accurate detection of LDL are needed. The purpose of this study was to develop an electrochemical platform for the detection of LDL based on an antibody–ferrocene conjugate. An anti-apolipoprotein B-100 antibody labeled with ferrocene was covalently immobilized on the layer of 4-aminothiophenol (4-ATP) on the surface of gold electrodes. Upon interaction between LDL and the antibody–ferrocene conjugate, a decrease in the ferrocene redox signal registered by square wave voltammetry was observed, which depends linearly on the concentration from 0.01 ng/mL to 1.0 ng/mL. The obtained limit of detection was equal to 0.53 ng/mL. Moreover, the satisfied selectivity toward human serum albumin (HSA), HDL, and malondialdehyde-modified low-density lipoprotein (MDA-LDL) was observed. In addition, the acceptable recovery rates of LDL in human serum samples indicate the possible application of immunosensors presented in clinical diagnostics.  相似文献   

18.
Current scientific evidence indicates that consumption of industrial trans fatty acids (TFA) produced via partial hydrogenation of vegetable oils increases the risk of coronary heart disease. However, some studies have suggested that ruminant TFA, especially vaccenic acid (VA or 11t-18:1) and rumenic acid (RA or 9c,11t-18:2), which is a conjugated linoleic acid (CLA) isomer, may have potential beneficial health effects for humans. To date, no concerted effort has been made to provide detailed isomer composition of ruminant TFA and CLA of Canadian dairy products, information that is required to properly assess their nutritional impacts. To this end, we analyzed the fatty acid profile of popular brands of commercial cheese (n = 17), butter (n = 12), milk (n = 8), and cream (n = 4) sold in retail stores in Ottawa, Canada, in 2006-2007 by silver nitrate thin-layer chromatography and gas liquid chromatography. The average total TFA content of cheese, butter, milk, and cream samples were 5.6, 5.8, 5.8, and 5.5% of total fatty acids, respectively. VA was the major trans-octadecenoic acid (18:1) isomer in all the Canadian dairy samples with average levels of (as % total trans-18:1) 33.9% in cheese, 35.6% in butter, 31.0% milk, and 30.1% in cream. The different dairy products contained very similar levels of CLA, which ranged from 0.5 to 0.9% of total fat. RA was the major CLA isomer of all the dairy products, accounting for 82.4-83.2% of total CLA. There were no significant differences (P > 0.05) in the fatty acid profile between the 4 different dairy groups, which suggests lack of processing effects on the fatty acid profile of dairy fat.  相似文献   

19.
A sensitive and reliable method was developed to determine methylene blue (MB) and its metabolite residues, including azure A (AZA), azure B (AZB), and azure C (AZC) in aquatic products by HPLC–MS/MS. The samples were extracted by acetonitrile and cleaned up by alumina-neutral (ALN) cartridges. The analytes were separated on a Sunfire C18 column (150 mm × 2.1 mm, 5 µm). The method was validated according to the European criteria of Commission Decision 2002/657/CE. Good linearity between 1–500 µg/L was obtained with correlation coefficients (R2) greater than 0.99. The limit of quantification (LOQ) was 1.0 µg/kg. The average recoveries at three levels of each compound (1, 5, and 10 µg/kg) were demonstrated to be in the range of 71.8–97.5%, with relative standard deviations (RSDs) from 1.05% to 8.63%. This method was suitable for the detection of methylene blue and its metabolite residues in aquatic products.  相似文献   

20.
The present research was undertaken to investigate polyphenolic profiles of peel, pulp and juices made from two standard commercial and five traditional apple cultivars from Bosnia and Herzegovina. The main goal of the study was to monitor the distribution and changes of polyphenolic profiles through different phases of apples’ processing into cloudy and clear juices, with regard to L-ascorbic acid pretreatment. Quantitative determination of phenolic compounds was carried out by using high-performance liquid chromatography with diode-array detection. The obtained results showed that traditional cultivars, namely ‘Paradija’ and ‘Prijedorska zelenika’, displayed significantly higher content of these compounds compared to commercial ones. Flavan 3-ols and flavonol glycosides were mostly found in peels of all cultivars (21.2–44.1 and 5.40–33.3%, respectively), while phenolic acids along with flavan 3-ols were predominant in the pulp (8.20–30.8 and 5.10–13.9%, respectively). Apples’ processing into juices caused decrease (more than 90%) in the content of all polyphenols and the distribution of these compounds from fruits to final products had a negative trend, particularly evident in clear juices. The most drastic loss occurred in the flavonol glycosides and dihydrochalcones content, while chlorogenic acid displayed quite stable distribution from apples to final products due to its good solubility. Apple mash pretreatment with L-ascorbic acid had a positive impact on the preservation and retention of polyphenols.  相似文献   

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