scholarly journals Impact of Extending Hard-Cheese Ripening: A Multiparameter Characterization of Parmigiano Reggiano Cheese Ripened up to 50 Months

Foods ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 268 ◽  
Author(s):  
Paolo D’Incecco ◽  
Sara Limbo ◽  
John Hogenboom ◽  
Veronica Rosi ◽  
Serena Gobbi ◽  
...  
Keyword(s):  
Solid Phase ◽  
Residual Activity ◽  
Short Chain Fatty Acids ◽  
Bacterial Cells ◽  
Structural Variations ◽  
Ripening Period ◽  
Continuous Release ◽  
Selected Traits ◽  
Parmigiano Reggiano ◽  
Hard Cheese

Extending ripening of hard cheeses well beyond the traditional ripening period is becoming increasingly popular, although little is known about the actual evolution of their characteristics. The present work aimed at investigating selected traits of Parmigiano Reggiano cheese ripened for 12, 18, 24, 30, 40 and 50 months. Two cheeses per each ripening period were sampled. Although moisture constantly decreased and was close to 25% in 50-month cheeses, with a parallel increase in cheese hardness, several biochemical changes occurred involving the activity of both native and microbial enzymes. Capillary electrophoresis demonstrated degradation of αs1- and β-casein, indicating residual activity of both chymosin and plasmin. Similarly, continuous release of free amino acids supported the activity of peptidases deriving from lysed bacterial cells. Volatile flavor compounds, such as short-chain fatty acids and some derived ketones, alcohols and esters, evaluated by gas chromatography with solid-phase micro-extraction, accumulated as well. Cheese microstructure was characterized by free fat trapped in irregularly shaped areas within a protein network, with native fat globules being no longer visible. This study showed for the first time that numerous biochemical and structural variations still occur in a hard cheese at up to 50 months of aging, proving that the ripening extension deserves to be highlighted to the consumer and may justify a premium price.

A combined metabolomics and peptidomics approach to discriminate anomalous rind inclusion levels in Parmigiano Reggiano PDO grated hard cheese from different ripening stages

2021 ◽  
Vol 149 ◽  
pp. 110654 ◽  
Author(s):  
Gabriele Rocchetti ◽  
Sara Michelini ◽  
Valentina Pizzamiglio ◽  
Francesco Masoero ◽  
Luigi Lucini
Keyword(s):  
Ripening Stages ◽  
Parmigiano Reggiano ◽  
Hard Cheese

Amino Acids as Food Quality Factors in Parmigiano Reggiano Hard Cheese

2017 ◽  
pp. 357-367 ◽  
Author(s):  
Franco Bellesia ◽  
Adriano Pinetti ◽  
Livia Simon-Sarkadi ◽  
Claudia Zucchi ◽  
János Csapó ◽  
...  
Keyword(s):  
Amino Acids ◽  
Food Quality ◽  
Quality Factors ◽  
Parmigiano Reggiano ◽  
Hard Cheese

scholarly journals MOX Sensors to Ensure Suitable Parameters of Grated Parmigiano Reggiano Cheese

Proceedings ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. 38
Author(s):  
Marco Abbatangelo
Keyword(s):  
European Union ◽  
Northern Italy ◽  
The European Union ◽  
Protected Designation Of Origin ◽  
Mox Sensors ◽  
Parmigiano Reggiano ◽  
Hard Cheese ◽  
Made In

Parmigiano Reggiano (PR) cheese is a long-ripened hard cheese made in Northern Italy registered as a Protected Designation of Origin (PDO) in the European Union. [...]

scholarly journals The propionic acid and butyric acid in serum but not in feces are increased in patients with diarrhea-predominant irritable bowel syndrome

2019 ◽  
Author(s):  
Zhenyi Tian ◽  
Xiaojun Zhuang ◽  
Mei Luo ◽  
Wei Yin ◽  
Lishou Xiong
Keyword(s):  
Irritable Bowel Syndrome ◽  
Butyric Acid ◽  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Short Chain Fatty Acids ◽  
Mass Spectrometric ◽  
Healthy Controls ◽  
Age And Gender ◽  
And Gender ◽  
Irritable Bowel

Abstract Background & Aims ： Short-chain fatty acids (SCFAs) play a pivotal role in maintaining homeostasis in humans. It might be involved in the pathogenesis of irritable bowel syndrome (IBS). Our study aims to explore the alteration of SCFAs in patients with diarrhea-predominant IBS (IBS-D). Methods： We recruited patients with IBS-D defined by Rome Ⅳ criteria and age-and-gender matched healthy controls (HCs). A headspace solid-phase microextraction gas chromatography–mass spectrometric (HS-SPME-GC-MS) method was developed for the analysis of acetic, propionic and butyric acid in feces and serum. Results: Compared with HCs, the levels of the serum propionate (2.957 ± 0.157 vs 2.843 ± 0.098 mmol/L, P = 0.012) and butyrate (2.798 ± 0.126 vs 2.697 ± 0.077 mmol/L, P = 0.012) were significantly higher in IBS-D group. No significant differences were found among two groups with regard to the concentration of fecal acetate (4.953 ± 1.065 vs 4.774 ± 1.465 mg/g, P = 0.679), propionate (6.342 ± 1.005 vs 6.282 ± 1.077 mg/g, P = 0.868) and butyrate (2.984 ± 0.512 vs 3.071 ± 0.447 mg/g, P = 0.607). Conclusions ： Metabolites of gut microbiota, the propionic and butyric acid, are increased in patients with IBS-D in serum but not in feces. It suggests that propionic and butyric acid might be involved in the pathogenesis of IBS.

Solid-phase enzyme-receptor assay (SPERA): a competitive-binding assay for glycopeptide antibiotics of the vancomycin class.

1985 ◽  
Vol 31 (10) ◽  
pp. 1606-1610 ◽  
Author(s):  
A Corti ◽  
C Rurali ◽  
A Borghi ◽  
G Cassani
Keyword(s):  
Human Serum ◽  
Binding Assay ◽  
Solid Phase ◽  
Quantitative Detection ◽  
Synthetic Analog ◽  
Bacterial Cells ◽  
Glycopeptide Antibiotics ◽  
Competitive Binding Assay ◽  
Analytical Recovery ◽  
Receptor Assay

Abstract A solid-phase enzyme-receptor assay (SPERA) has been developed for glycopeptide antibiotics of the vancomycin class such as teicoplanin, vancomycin, ristocetin, avoparcin, actaplanin, A-47934, A-41030, and A-35512-B. The assay exploits the mechanism of most action of these antibiotics, which is based on their interaction with acyl-D-alanyl-D-alanine, a constituent of the walls of most growing bacterial cells. The antibiotics and enzyme-labeled teicoplanin compete for a synthetic analog of the biological receptor, albumin-epsilon-aminocaproyl-D-alanyl-D-alanine. The various antibiotics produced different competition curves, 50% displacement being obtained with antibiotic concentrations ranging from 0.04 to 4 mg/L, vancomycin and actaplanin being the weakest and strongest competitors, respectively. For teicoplanin in human serum the intra-assay CV was 7.2%, the interassay CV was 11.2%, and the analytical recovery 94%. Teicoplanin concentrations obtained by SPERA (chi) correlated well with those obtained by microbiological assay (y): y = 1.03 chi + 0.053 (r = 0.943; n = 60). We conclude that SPERA is a powerful tool for identification and quantitative detection of glycopeptide antibiotics, even in complex media.

scholarly journals Oncorhyncin III: a potent antimicrobial peptide derived from the non-histone chromosomal protein H6 of rainbow trout, Oncorhynchus mykiss

2003 ◽  
Vol 373 (2) ◽  
pp. 621-628 ◽  
Author(s):  
Jorge M. O. FERNANDES ◽  
Nathalie SAINT ◽  
Graham D. KEMP ◽  
Valerie J. SMITH
Keyword(s):  
Rainbow Trout ◽  
Antimicrobial Peptide ◽  
Lipid Bilayers ◽  
Solid Phase ◽  
Reversed Phase ◽  
Exchange Chromatography ◽  
Haemolytic Activity ◽  
Acid Extraction ◽  
Chromosomal Protein ◽  
Bacterial Cells

A 6.7 kDa antimicrobial peptide was isolated from trout skin secretions using acid extraction followed by cation-exchange chromatography, tC18 solid-phase extraction, and C18 reversed-phase HPLC. The molecular mass of this peptide, which is tentatively named oncorhyncin III, is 6671 Da, as determined by matrix-assisted laser-desorption ionization MS. N-terminal amino acid sequencing revealed that the first 13 residues of oncorhyncin III are identical with those of the non-histone chromosomal protein H6 from rainbow trout. Hence these data combined with the MS results indicate that oncorhyncin III is likely to be a cleavage product of the non-histone chromosomal protein H6 (residues 1–66) and that it probably contains two methylated residues or one double methylation. The purified peptide exhibits potent antibacterial activity against both Gram-positive and Gram-negative bacteria, with minimal inhibitory concentrations in the submicromolar range. The peptide is sensitive to NaCl, and displays no haemolytic activity towards trout erythrocytes at concentrations below 1 μM. Scanning electron microscopy revealed that oncorhyncin III does not cause direct disruption of bacterial cells. Reconstitution of the peptide in planar lipid bilayers strongly disturbs the membranes, but does not induce the formation of stable ion channels. Taken together, these results support the hypothesis that oncorhyncin III plays a role in mucosal innate host defence.

scholarly journals Comparison of Fluorescence Microscopy and Solid-Phase Cytometry Methods for Counting Bacteria in Water

2004 ◽  
Vol 70 (9) ◽  
pp. 5343-5348 ◽  
Author(s):  
John T. Lisle ◽  
Martin A. Hamilton ◽  
Alan R. Willse ◽  
Gordon A. McFeters
Keyword(s):  
Bacterial Abundance ◽  
Solid Phase ◽  
Fluorescent Microscopy ◽  
Industrial Applications ◽  
Bacterial Cells ◽  
Abundance Estimate ◽  
Statistical Confidence ◽  
Quality Of Water ◽  
Microscopic Count ◽  
Direct Counts

ABSTRACT Total direct counts of bacterial abundance are central in assessing the biomass and bacteriological quality of water in ecological and industrial applications. Several factors have been identified that contribute to the variability in bacterial abundance counts when using fluorescent microscopy, the most significant of which is retaining an adequate number of cells per filter to ensure an acceptable level of statistical confidence in the resulting data. Previous studies that have assessed the components of total-direct-count methods that contribute to this variance have attempted to maintain a bacterial cell abundance value per filter of approximately 106 cells filter−1. In this study we have established the lower limit for the number of bacterial cells per filter at which the statistical reliability of the abundance estimate is no longer acceptable. Our results indicate that when the numbers of bacterial cells per filter were progressively reduced below 105, the microscopic methods increasingly overestimated the true bacterial abundance (range, 15.0 to 99.3%). The solid-phase cytometer only slightly overestimated the true bacterial abundances and was more consistent over the same range of bacterial abundances per filter (range, 8.9 to 12.5%). The solid-phase cytometer method for conducting total direct counts of bacteria was less biased and performed significantly better than any of the microscope methods. It was also found that microscopic count data from counting 5 fields on three separate filters were statistically equivalent to data from counting 20 fields on a single filter.

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