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Nutritional composition analysis and quality evaluation of cattle in different regions of Guizhou Province (China)
2023
HaoXiang Xu | WenJu Luo | Lu Lei | Long JiuLing | Bo Yu | YuanFeng Zhao | Rong Ai | Jiang Lingling | Jiang Ran | JingRui Zhou (email: 296655827@qq.co
This study aimed to investigate the variations in nutritional composition among different breeds of cattle in Guizhou. Specifically, this study selected Guanling, Weining, Sinan, Wuchuan, and Simmental cattle as experimental subjects. Assessing the nutritional quality of the longissimus dorsi muscle involves evaluating various parameters, including ultimate pH (pHu), meat colour, water-holding capacity, shear force, protein and fat content, levels of organic acids and amino acid composition. The study's findings indicated notable variations among the muscles of different cattle breeds tested. Guanling, Wuchuan, and Simmental cattle exhibited the highest water-holding capacity, while Wuchuan cattle displayed the highest shear forces. Guanling cattle and Simmental cattle had the highest levels of protein and fat. Weining cattle and Simmental cattle demonstrated the highest concentrations of lactic acid and oxalic acid. Guanling cattle exhibited the highest total amino acid and essential amino acid content. Moreover, Guanling cattle and Weining cattle showed the highest lightness (L*) and yellowness (b*) values, indicating lighter meat colour, while Weining cattle had the highest redness (a*) value, indicating redder meat colour. No significant differences among the five cattle breeds were observed in pHu and propionic acid content. These results provide a theoretical basis and serve as a data reference for assessing the suitability of different beef varieties for various processing purposes.
Afficher plus [+] Moins [-]Experimental evaluation of milk yield and selected traits of milk quality in Clun Forest ewes
2023
Jan Kuchtík | Květoslava Šustová | Tomáš Kopec | Ferenc Pajor | Leona Konečná
In general, it can be stated that the economics of non-dairy sheep breeding in the Czech Republic experienced a worsening trend in recent years. One of the ways to improve this situation is to use some of these breeds also for milk production. One of the possible breeds usable for milk production, especially for the good milk production of mothers, is the Clun Forest (CF). The aim of our experiment was to evaluate the daily milk yield (DMY) and the contents of fat (F), total protein (TP) and lactose (L), pH, titratable acidity (TA), concentration of urea (CU) and somatic cell count (SCC) in CF ewes during lactation. In our experiment, the following means of individual traits for the whole lactation were found: DMY: 579 g, contents of F, TP and L: 6.73%, 5.82% and 4.98%, pH: 6.55, TA: 8.74 °SH, CU: 36.08 mg/100 ml and log SCC: 4.71. The stage of lactation had a significant (P < 0.01) effect on DMY, contents of F and TP and pH and TA. The results of our experiment show that CF ewes had lower DMY than dairy breeds (DB). However, the majority of the milk quality traits was comparable to DB. Moreover, the high fat and protein contents and the values of most other milk quality traits are good prerequisites for high cheese yield and optimal final quality of other sheep's milk products. The results of our experiment suggest that CF ewes could be used for milk production while the milk production of CF ewes should ensure an improvement in the economics and competitiveness of smaller farms in particular.
Afficher plus [+] Moins [-]Incidence of aflatoxin M1 in cows' milk in Pakistan, effects on milk quality and evaluation of therapeutic management in dairy animals
2023
I Ullah | A Nasir | M Kashif | A Sikandar | M Sajid | M Adil | A Rehman | MU Iqbal | H Ullah
The present study was aimed at measuring the concentration of aflatoxin M1 (AFM1) in the milk of Holstein Friesian cows, its effect on the milk quality and seasonal trends, as well as to investigate the efficacy of a commercial clay-based toxin binder. For this purpose, milk samples from dairy cows (n = 72) were collected and assayed for AFM1 before employing a clay-based toxin binder. The milk samples (n = 72) were collected from selected animals, revealing that 69.4% of the milk samples had AFM1 levels above the United States permissible limit (0.5 µg/kg). The incidence of AFM1 in milk during the winter and summer was 82.5% and 53.1%, respectively. Owing to the presence of AFM1, the level of milk fat, solids-not-fat, and protein were found to be low. Subsequently, the affected animals were divided into two groups, i.e., AFM1 positive control (n = 10) and the experimental group (n = 40). The experimental group of animals were fed the clay-based toxin binder at 25 g/animal/day. A progressive decrease of 19.8% in the AFM1 levels was observed on day 4 and on day 7 (53.6%) in the treatment group. Furthermore, the fat, solids-non-fat and protein increased significantly in the milk. In conclusion, a high level of AFM1 contamination occurs in the milk in Pakistan, affecting the quality of the milk production. Clay-based toxin binders may be used to ensure the milk quality and to protect the animal and consumer health.
Afficher plus [+] Moins [-]Evaluation of the physicochemical and hygienic quality of cow’s milk and its derivatives in El Jadida city Morocco
2023
Najat Ariri | Hamid Aboukhassib | Nadia Echarrafi | Nysrine Mannani | Aziz Fitani | Abdelali Bitar
Background. Despite the efforts and investments made for traceability and the guarantee of a fair and safe milk product, the informal sector threatens the safety of milk. In fact, during this circuit, the product does not undergo any treatment and therefore presents serious risks for the health of the consumer. In this context, studies have been carried out on samples of peddled milk and products derived from it. Objective. The purpose of this study is to evaluate the relevance of the informal circuit in Morocco's Doukkala region (El Jadida Province) by physicochemical and microbiological investigation of raw milk and its derivatives at various points of sale. Materials and method. 84 samples were taken between (23 for raw milk, 30 for the «Lben», and 31 for the «Raib») between January 1st, 2021 and October 30th, 2021. According to Moroccan rules, microbiological analyses revealed an extremely high non-compliance rate in most samples obtained at the level of outlets situated in the El Jadida region, with a non-compliance ratio of 65 percent for raw milk sold, 70 percent for the «Lben», and 40 percent for the «Raib». Results. Likewise, these analyses revealed that majority of the samples did not fulfill international criteria for the pH values of raw milk samples «Lben» and «Raib», which are respectively between 5.85 and 6.71; 4.14 and 4.43 and 4.5. Other characteristics, including lactose, proteins, fat, mineral salts, density, and additional water, have also yielded results. Conclusion. This has allowed us to analyze the major impact of the peddling circuit at the regional level, which is a risk factor for consumer health.
Afficher plus [+] Moins [-]Bynær dyrking med resirkulert gjødsel? En vurdering av tungmetallrisiko
2023
Løes, Anne-Kristin | Rittl, Tatiana | Eiter, Sebastian | Haraldsen, Trond K.
Mange som dyrker grønnsaker til direkte salg er interessert i økologiske driftsmetoder. Det er mye organisk materiale tilgjengelig i byer og tettbygde strøk. Matrester og avfall fra hager og parker kan bli til både energi og gjødsel, som kan brukes i dyrking av grønnsaker i bynære strøk. Da får vi korte verdikjeder, men hva med innholdet av tungmetaller? Beregninger viser at grenseverdier i jord vil mettes først for kobber og sink, som også er viktige mikronæringsstoffer. for planter. Jordforbedringsmidler med høyt innhold av organisk materiale, som hage-park kompost og hestegjødsel, inneholder mer tungmetaller per kg tørrstoff enn fjørfegjødsel og utråtnet matavfall.
Afficher plus [+] Moins [-]Developing radio frequency (RF) heating protocol in packed tofu processing by computer simulation
2023
Baozhong Cui | Pengfei Ye | Ke Wang | Yanan Sun | Chao Mao | Huiyun Pang | Hongfei Fu | Yequn Wang | Xiangwei Chen | Yunyang Wang
Packed tofu was produced by reheating the mixture of preheated soymilk and coagulant in a sealed container. This study aimed to replace the conventional heating method with RF heating during the reheating of soymilk for packed tofu production. In this study, dielectric properties (DPs), thermal properties (TPs), and rheological properties of soymilk were determined. A mathematical model was developed to simulate the RF heating process of soymilk to determine the appropriate packaging geometry. Water holding capacity (WHC), texture analysis, color measurement, and microstructure observation were performed to evaluate the quality of RF-heated packed tofu. Results showed that soymilk added with Glucono-Delta-Lactone (GDL) coagulated at the temperature above 60 °C, and the loss factor (ε″) was slightly reduced when soymilk was converted to tofu at coagulation temperature. Based on the simulation results, the cylindrical vessel (φ50 mm × 100 mm) was chosen as the soymilk container for desired heating rate (5.9 °C/min) and uniformity (λ = 0.0065, 0.0069, 0.0016 for top, middle, and bottom layers). The texture analysis revealed that the hardness and chewiness of packed tofu prepared by RF heating were enhanced (maximum 1.36 times and 1.21 times) compared with commercial packed tofu, while the springiness were not significantly changed. Furthermore, the denser network structure was observed inside RF-heated packed tofu by SEM. These results indicated that packed tofu prepared by RF heating was of higher gel strength and sensory quality. RF heating has the potential to be applied in packed tofu production.
Afficher plus [+] Moins [-]Water-Rock Action Analysis and Quality Evaluation of Shallow Groundwater in Rural Areas: A Case Study of Suzhou City, Northern Anhui, China
2023
Li Gao | Jingyu Zhao | Hongtao Zhao | Jiying Xu | Jiewei Xu | Shuxin Han | Ling Wang | Xiaoyue Wang | Yonglie Shu
Groundwater is the main water source for humans and plays an important role in health and food production. To understand the hydrogeochemical characteristics and quality of shallow groundwater in rural areas of Suzhou, Anhui Province, China, 32 groups of shallow groundwater samples were collected. The results of the study showed that the nature of the groundwater is slightly alkaline. The order of abundance of cations is Ca<sup>2+</sup> > K<sup>+</sup> + Na<sup>+</sup> > Mg<sup>2+</sup>, whereas that of anions is HCO<sub>3</sub><sup>−</sup> > Cl<sup>−</sup> > SO<sub>4</sub><sup>2−</sup>. The main hydrochemical types are HCO<sub>3</sub>-Ca, HCO<sub>3</sub>-Mg, and HCO<sub>3</sub>-Na. Hydrogen and oxygen isotope abundances indicated that shallow groundwater recharge in the study area is due to precipitation and is affected by evaporation. The ion ratio analysis suggested that the ions in the shallow groundwater originate from the weathering of silicate minerals and the dissolution of carbonate and sulphate minerals, accompanied by different degrees of ion exchange. Water quality evaluation indicated that the water is good and can be used directly as agricultural irrigation water.
Afficher plus [+] Moins [-]Study on Environmental Quality and Prevention of Soil Salinization in Northern Shandong Plain (North of Yellow River)
2023
ZHANG Hongjun | XU Yan | WANG Qiang | ZHANG Taiping | ZHAO Hui | WANG Wei | ZHANG Ruihua | WANG Kuifeng
【Objective】 Soil salinity is a common abiotic stress most crops experience during their growth. Understanding its spatiotemporal variation and the underlying reasons is impetus to improve agricultural management. We propose a model in this paper to classify soil salinity and analyze the underlying mechanisms. The model is applied to the North of Yellow River in Northern Shandong Plain. 【Method】 The model is based on the two - level fuzzy comprehensive evaluation method. A comprehensive evaluation index system is constructed using soil environment factors, groundwater environmental factors, and physical geographical factors. It considered eight indexes: proportion of land areas affected by salinized soil, degree of soil salinity, soil salt content, lithology of unsaturated zone, depth of groundwater table, groundwater salinity, evaporation-prescription ratio, and topography and landform. The degree of soil quality was divided into excellent, good, moderate, poor, and very poor grades. 【Result】 The areas of soil classified as very poor, poor, moderate, good and excellent based on soil salinization were 5 277.49 km2, 6 564.76 km2, 4 383.79 km2, 5 995.52 km2, and 4 919.29 km2, respectively. Based on their genesis and salinization, the salinized soils in the region can be divided to three areas consisting of eight sub-areas. 【Conclusion】 Soil salinity in the North of Yellow River in Northern Shandong Plain varies in its severity and space. The results presented in this paper can aid in improving soil management practices to promote a healthy agricultural and rural economy in the region.
Afficher plus [+] Moins [-]Soil Quality Evaluation for Cotton Fields in Arid Region Based on Graph Convolution Network
2023
Xianglong Fan | Pan Gao | Li Zuo | Long Duan | Hao Cang | Mengli Zhang | Qiang Zhang | Ze Zhang | Xin Lv | Lifu Zhang
Accurate soil quality evaluation is an important prerequisite for improving soil management systems and remediating soil pollution. However, traditional soil quality evaluation methods are cumbersome to calculate, and suffer from low efficiency and low accuracy, which often lead to large deviations in the evaluation results. This study aims to provide a new and accurate soil quality evaluation method based on graph convolution network (GCN). In this study, soil organic matter (SOM), alkaline hydrolysable nitrogen (AN), available potassium (AK), salinity, and heavy metals (iron (Fe), copper (Cu), manganese (Mn), and zinc (Zn)) were determined and evaluated using the soil quality index (SQI). Then, the graph convolution network (GCN) was first introduced in the soil quality evaluation to construct an evaluation model, and its evaluation results were compared with those of the SQI. Finally, the spatial distribution of the evaluation results of the GCN model was displayed. The results showed that soil salinity had the largest coefficient of variation (86%), followed by soil heavy metals (67%) and nutrients (30.3%). The soil salinization and heavy metal pollution were at a low level in this area, and the soil nutrients and soil quality were at a high level. The evaluation accuracy of the GCN model for soil salinity/heavy metals, soil nutrients, and soil quality were 0.91, 0.84, and 0.90, respectively. Therefore, the GCN model has a high accuracy and is feasible to be applied in the soil quality evaluation. This study provides a new, simple, and highly accurate method for soil quality evaluation.
Afficher plus [+] Moins [-]Study on Denoising Method of Photoionization Detector Based on Wavelet Packet Transform
2023
Zengyuan Liu | Xiujuan Feng | Chengliang Dong | Mingzhi Jiao
Aiming at the task of noise suppression caused by the photoionization detector (PID) monitoring signal of volatile organic compounds (VOCs) due to local non-uniformity of the photocathode surface of PID in the ionization chamber, this paper proposes an analytical method of a PID signal with the adaptive weight of the small wave package decomposition node. The PID signal is transmitted to the upper machine software through the single-chip microcontroller. The appropriate wavelet packet decomposition level is determined according to the time frequency characteristics of the original signal of the PID, and the optimal wavelet packet base is selected through the polynomial fitting of the signal quality evaluation index. By comparing the quality of signals processed by the traditional wavelet packet denoising method and the denoising method presented in this paper, the superiority of the proposed method in the denoising signals of PID was verified. This method can eliminate the noise generated by local non-uniformity on the photocathode surface of the PID ionization chamber in a high humidity environment, which lays a foundation for the accurate monitoring of VOCs in a high humidity environment.
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