Effects of rapid chilling of carcasses and time of deboning on weight loss and technological quality of pork semimembranosus muscle.

The effect of rapid air chilling of carcasses in the first 3 h of chilling at -31°C (then at 2-4°C, till 24 h post-mortem) and the possibility of earlier deboning (8 h post-mortem) after rapid air chilling, compared to conventional air chilling (at 2-4°C, till 24 h post-mortem) on weight loss and technological quality (pH value, tenderness, drip loss, cooking loss and colour - L(∗)a(∗)b(∗) values) of pork M. semimembranosus was investigated. Under the rapid chilling conditions, weight loss was 0.8% at 8 h post-mortem and increased to 1.4% at 24 h post-mortem when weight loss was 2.0% under conventional chilling. Carcasses that were rapid chilled had significantly lower (P<0.001) internal temperature in the deep leg at 4 (25.7°C), 6 (13.0°C), 8 (6.2°C) and 24 h (3.8°C) post-mortem compared to conventional chill treatment (32.7, 24.2, 19.1 and 5.1°C, respectively). Rapid chilling reduced significantly (P<0.05) the rate of pH value decline at 8 h (6.02) post-mortem in M. semimembranosus compared to conventional chill treatment (5.88). Compared to conventional chilling, in M. semimembranosus deboned in different time post-mortem, rapid chilling had a positive significant effect on drip loss (P<0.05, muscles deboned 8 h post-mortem), cooking loss (P<0.001) and incidence of pale colour (L(∗) value). Rapid chilling i.e. rapid chilling and earlier deboning had neither positive nor negative significant effects (P>0.05) on other investigated technological quality parameters of M. semimembranosus (tenderness, a(∗) value and b(∗) value) compared to conventional chilling.

HPLC determination of tiazofurin in the rat brain.

A sensitive, selective and reproducible HPLC method for determination of tiazofurin in rat brain was developed and validated. The method allowed determination and quantification of nanomolar concentrations of tiazofurin in brain and its regions (hippocampus, cortex and striatum) of treated animals. Separation of tiazofurin from other peaks from brain tissue was achieved by isocratic elution on reverse phase chromatographic column. The mobile phase consisted of 0.05 M sodium acetate pH 4.6. Run time was 15 min.

Lipid oxidative changes in chitosan-oregano coated traditional dry fermented sausage Petrovská klobása.

The effect of a chitosan coating with added essential oil of oregano (Origanum vulgare) on lipid oxidation of dry fermented sausage (Petrovská klobása) was investigated. Fatty acid profile, aldehyde contents and sensory analysis of odor and flavor were determined after drying and during seven months of storage. Between coated and control sausage, a difference was observed after two months storage in fatty acid profiles (myristic, oleic and linoleic acids), but after seven months storage there was no difference. Decrease in polyunsaturated acid content was observed (from 17.25% to 15.70%), as well as an increase in total aldehydes (from 4.54 µg/g to 31.80 µg/g), due to lipid oxidation during storage. After seven months storage, the content of most aldehydes was significantly lower in coated sausage than in the control. Sensory characteristics of odor and flavor were better for coated sausage, after seven months of storage. Results suggest that chitosan-oregano coating can be successfully applied to protect dry fermented sausages from lipid oxidation.

Sensory, physical and chemical characteristics of cooked ham manufactured from rapidly chilled and earlier deboned M. semimembranosus.

Effects of rapid chilling of carcasses (at -31°C in the first 3h of chilling, and then at 2-4°C) and earlier deboning (8h post-mortem), compared to rapid (till 24h post-mortem) and conventional chilling (at 2-4°C, till 24h post-mortem), on quality characteristics of pork M. semimebranosus and cooked ham were investigated. Quality measurements included pH value, colour (CIEL a b values) and total aerobic count of M. semimebranosus, as well as sensory (colour, juiciness, texture, and flavour), physical (pH value, colour - CIEL a b values and texture - Warner-Bratzler shear and penetration forces) and chemical (protein, total fat, and moisture content) characteristics of cooked ham. The cooked ham was manufactured from pieces of M. semimebranosus with ultimate lightness (CIEL value) lower than 50. Rapid chilling and earlier deboning significantly increased quantity of M. semimebranosus desirable for cooked ham manufacturing. Earlier start of pork fabrication did not affect important quality characteristics of cooked ham.

The characterisation of lactic acid bacteria during the fermentation of an artisan Serbian sausage (Petrovská Klobása).

Petrovská Klobása is an artisan Serbian sausage made only from meat and spices without any additives or starter cultures. In order to characterise lactic acid bacteria (LAB) microflora, a total number of 404 LAB strains were isolated from 15 samples collected during 90 days of the fermentation and 120 days of storage of one batch of Petrovská Klobása. The isolates were preliminarily identified by phenotypic tests and subjected to (GTG)5-PCR fingerprinting. Representatives of each group were identified by 16S rDNA sequencing. The results showed that among the isolates, Lactobacillus sakei and Leuconostoc mesenteroides predominate with 36.4% and 37.1% of total LAB strains, respectively. Pediococcus pentosaceus was also isolated in high proportion (18.4%) whereas Enterococcus durans and Enterococcus caseliflavus made only 1% and 6% of the total isolates, correspondingly. The analysis of vacuum packed and modified atmosphere packed (MAP) samples showed higher presence of L. mesenteroides and L. sakei in the total microflora.

Justification of metformin hydrochloride biowaiver criteria based on bioequivalence study.

The Biopharmaceutics Classification System (BCS) represents the framework for predicting the intestinal drug absorption based on its solubility and intestinal permeability. Recent research has lead to the use of in vitro tests to waive additional in vivo bioequivalence studies for some pharmaceutical products (i.e., biowaiver). The current regulations permit waivers for BCS Class I (highly soluble/highly permeable) drug substances, which represent up to 25% of the drugs. Efforts in both the science and regulatory bodies are being made to extend biowaivers to certain Class II and III products, which would represent more than 50% of all drugs coming to the market. The aim of this study was to investigate the influence of experimental conditions on metformin hydrochloride (CAS 1115-70-4) release from two immediate-release tablet formulations with proven bioequivalence and justify the biowaiver request for dissolution profile similarity in three pH media. The results obtained indicate that differences in drug dissolution observed in vitro were not reflected in vivo. Such data support the existing idea that BCS Class III drugs are eligible biowaiver candidates, even if a very rapid dissolution criterion is not fulfilled.