The impact of raw milk quality on product quality

Milk Quality ◽  
1995 ◽  
pp. 102-111 ◽  
Author(s):  
F. Harding
2016 ◽  
Vol 99 (12) ◽  
pp. 10128-10149 ◽  
Author(s):  
Steven C. Murphy ◽  
Nicole H. Martin ◽  
David M. Barbano ◽  
Martin Wiedmann

Author(s):  
Oto Hanuš ◽  
Irena Němečková ◽  
Jan Pozdíšek ◽  
Igor Huňády ◽  
Marcela Klimešová ◽  
...  

Current changes in climate (increasing drought) and the rise in prices of protein concentrate feed are the reasons for the increasing interest in growing and production and increasing silages from legume‑cereal mixtures (LCM) in rations for dairy cows. Another reason is to improve the soil fertility using LCM in crops rotation. The impact of feeding of dairy cows (Czech Fleckvieh and Holstein, 50 herds) on milk quality was monitored (for 3 years) when modifying the roughage feeding rations by additions of LCM silages. Bulk milk samples were tested (n = 641 (15 herds) LCM as experiment and 2,428 (35) as control). LCM was higher in crude protein, lactose, solids non‑fat and total microorganisms (from P ≤ 0.05 to P ≤ 0.001). The lower was LCM in the milk freezing point and the urea content (P < 0.05 and P < 0.001). The fat content and the somatic cell count were insignificantly different (P > 0.05). There was a significant effect of LCM on milk thermostability (18.85 < 20.9 minutes, P < 0.05). The residues of inhibitory substances in milk were not recorded in the LCM group. The LCM application is a risk‑free way of replacement of roughage component part of dairy cow feeding rations with regard to raw milk quality.


Domiati cheese is the most popular brand of cheese ripened in brine in the Middle East in terms of consumed quantities. This study was performed to investigate the impact of the microbiological quality of the used raw materials, the applied traditional processing techniques and ripening period on the quality and safety of the produced cheese. Three hundred random composite samples were collected from three factories at Fayoum Governorate, Egypt. Collected samples represent twenty-five each of: raw milk, table salt, calf rennet, microbial rennet, water, environmental air, whey, fresh cheese, ripened cheese & swabs from: worker hands; cheese molds and utensils; tanks. All samples were examined microbiologically for Standard Plate Count (SPC), coliforms count, Staphylococcus aureus (S. aureus) count, total yeast & mould count, presence of E. coli, Salmonellae and Listeria monocytogenes (L. monocytogenes). The mean value of SPC, coliforms, S. aureus and total yeast & mould counts ranged from (79×102 CFU/m3 for air to 13×108 CFU/g for fresh cheese), (7×102 MPN/ cm2 for tank swabs to 80×106 MPN/ml for raw milk), (9×102 CFU/g for salt to 69×106 CFU/g for fresh cheese) and (2×102 CFU/cm2 for hand swabs to 60×104 CFU/g for fresh cheese), respectively. Whereas, E. coli, Salmonella and L. monocytogenes failed to be detected in all examined samples. There were significant differences in all determined microbiological parameters (p ≤0.05) between fresh and ripened cheese which may be attributed to different adverse conditions such as water activity, pH, salt content and temperature carried out to improve the quality of the product.


Author(s):  
Annemarie Siebert ◽  
Katharina Hofmann ◽  
Lena Staib ◽  
Etienne V. Doll ◽  
Siegfried Scherer ◽  
...  

Abstract The highly complex raw milk matrix challenges the sample preparation for amplicon-sequencing due to low bacterial counts and high amounts of eukaryotic DNA originating from the cow. In this study, we optimized the extraction of bacterial DNA from raw milk for microbiome analysis and evaluated the impact of cycle numbers in the library-PCR. The selective lysis of eukaryotic cells by proteinase K and digestion of released DNA before bacterial lysis resulted in a high reduction of mostly eukaryotic DNA and increased the proportion of bacterial DNA. Comparative microbiome analysis showed that a combined enzymatic and mechanical lysis procedure using the DNeasy® PowerFood® Microbial Kit with a modified protocol was best suitable to achieve high DNA quantities after library-PCR and broad coverage of detected bacterial biodiversity. Increasing cycle numbers during library-PCR systematically altered results for species and beta-diversity with a tendency to overrepresentation or underrepresentation of particular taxa. To limit PCR bias, high cycle numbers should thus be avoided. An optimized DNA extraction yielding sufficient bacterial DNA and enabling higher PCR efficiency is fundamental for successful library preparation. We suggest that a protocol using ethylenediaminetetraacetic acid (EDTA) to resolve casein micelles, selective lysis of somatic cells, extraction of bacterial DNA with a combination of mechanical and enzymatic lysis, and restriction of PCR cycles for analysis of raw milk microbiomes is optimal even for samples with low bacterial numbers. Key points • Sample preparation for high-throughput 16S rRNA gene sequencing of raw milk microbiota. • Reduction of eukaryotic DNA by enzymatic digestion. • Shift of detected microbiome caused by high cycle numbers in library-PCR.


2017 ◽  
Vol 29 (1) ◽  
pp. 82-100
Author(s):  
Svetoslav Georgiev ◽  
Emil Georgiev

Purpose The purpose of this paper is to analyse the evolution of top management’s understanding of product quality in Bulgaria since the end of communism. The study examines three specific areas: top management’s understanding of the term “quality”; top management’s understanding of the relationship between quality and business performance; and top management’s understanding of the impact of job position on quality. Design/methodology/approach The paper relies on a quantitative research approach by using data from a survey of 186 companies in Bulgaria. Findings The paper suggests that senior managers in Bulgaria continue to base their understanding of “quality” on a single approach (*a characteristic of the communist era), with the product-based and the user-based approaches currently being the two most common ones. At the same time, surprisingly enough, this study claims that senior management in Bulgaria is currently well aware of the importance of quality as a dimension of firm’s competitiveness, and is also highly conscious of its roles’ impact on product quality. Research limitations/implications The results of this study are exclusively based on the case of Bulgaria and must be treated with caution in the case of other former communist states from the Central and Eastern Europe (CEE) region. Practical implications This paper has relevance for both managers and companies doing business in Eastern Europe. Originality/value This is the first paper to provide detailed analysis of the evolution of the understanding of “product quality” in CEE since the end of communism. Moreover, this paper applies, for the first time, Garvin’s five approaches to defining quality within a practical context.


2021 ◽  
Author(s):  
Omesh Kini ◽  
Mo Shen ◽  
Jaideep Shenoy ◽  
Venkat Subramaniam

In this paper, we study the impact of labor unions on product quality failures. We use a product recall as our measure of quality failure because it is an objective metric that is applicable to a broad cross-section of industries. Our analysis employs a union panel setting and close union elections in a regression discontinuity design framework to overcome identification issues. In the panel regressions, we find that firms that are unionized and those that have higher unionization rates experience a greater frequency of quality failures. The results obtain even at a more granular establishment level in a subsample in which we can identify the manufacturing establishment associated with the recalled product. When comparing firms in close elections, we find that firms with close union wins are followed by significantly worse product quality outcomes than those with close union losses. These results are amplified in non–right-to-work states, where unions have a relatively greater influence on the workforce. We find that unionization increases firms’ costs and operating leverage and, consequently, crowds out investments that potentially impact quality. We also find some suggestive evidence that unions may compromise quality by hurting employee morale and by resisting technological upgrades in the firm. Overall, our results suggest that unions have an adverse impact on product recalls, and thus, product quality is an important dimension along which unions impact businesses. This paper was accepted by Gustavo Manso, finance.


1989 ◽  
Vol 21 (2) ◽  
pp. 63-75
Author(s):  
William A. Schiek ◽  
Emerson M. Babb

AbstractThe Southeast is a net importer of milk and milk products. Milk must be imported from other regions at certain times of the year. Reverse osmosis (RO) is a new processing technology which could significantly reduce milk transportation costs between regions by removing half the water from raw milk prior to shipment. A network flow algorithm, which incorporates federal milk orders and solves for the least cost procurement pattern, was used to assess the impact of RO on southeast milk marketing orders under alternative raw product pricing scenarios.


2016 ◽  
Vol 32 (2) ◽  
pp. 133-143 ◽  
Author(s):  
Denis Kucevic ◽  
Snezana Trivunovic ◽  
Vladan Bogdanovic ◽  
Ksenija Cobanovic ◽  
Dobrila Jankovic ◽  
...  

Possible differences between composition of raw milk due to dairy farming system (organic vs conventional) as well as seasonal variations were investigated. The samples were analysed during one year. A total of 6.782 samples of raw milk were collected (4.496 from organic farming). Dairy farms were located in the northern part of Republic of Serbia (Province of Vojvodina). The principle of analysis of raw milk samples was in accordance with the methodology by midinfrared spectrometry and flow cytometry. The fixed effect of system of farming and season (winter, spring, summer and fall) have shown a high statistical significance (P < 0.01) on all examined milk parameters except fat, total solids and somatic cell count, where the impact was slightly lower (P < 0.05). Significant difference wasn't found in number of bacterial colonies (P > 0.05). Composition of milk is also affected by a number of other factors, therefore it is recommended to involve factors such as nutrition of dairy cows, breed and farm management.


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