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A study was conducted to determine the effects of journey duration (1 versus 3 h) and lairage time at abattoir (0 versus 5 h) on rabbit meat quality traits. Rabbits transported for 3 h produced meat with significantly higher pH values (P

Addresses the major areas of instrumentation of food analysis as well as instruments for sample processing of foods and for food analysis. Presents novel analysis instruments such as microwave-assisted process and nuclear magnetic resonance spectroscopy. Covers food analysis instruments based on chromatography, mass spectroscopy, and hyphenated techniques. Includes a color insert, more than 200 black and white illustrations, more than 40 tables, and 100 equations. Provides information on instruments to analyze food components and additives in lab studies. The identification, speciation, and determination of components, additives, and contaminants in raw materials and products will always be a critical task in food processing and manufacturing. With contributions form leading scientists, many of whom actually developed or refined each technique or instrument, the Handbook of Food Analysis Instruments discusses how to apply proper methods and use increasingly sophisticated instruments.

It is known that virgin olive oil (VOO) has higher nutritional quality and health benefits – especially due to the presence of a wealth of phenolic compounds - in comparison to other vegetable oils. Unfortunately, it is also well known that a great number of olive oils fraudulently sold as VOOs are actually illegally mixed with other cheaper olive oils of lower quality and poorer characteristics. The so-called "mild deodorized" olive oils are nowadays the most used adulterants, because of their difficulty of being detected when in mixture with VOOs. These oils commonly show physico-chemical characteristics similar to genuine VOOs. In addition, the mild conditions illegally applied for their deacidification and deodorization do not lead to the formation of chemical markers that could be exploited as forensic proofs of the fraud. Microwave heating is commonly utilized for home cooking, food catering and industrial processes. Microwave heating was reported to induce significantly higher amount of compounds formed by oxidation and hydrolysis of lipids in comparison with traditional cooking treatments, probably as the result of a different extent of radical formation. In this preliminary study, mild deodorized olive oil and their mixtures with VOO have been analyzed after heating treatments by microwave and conventional oven. Different patterns in oxidative and hydrolytic degradation of lipids in genuine and sophisticated olive oils have been evaluated by chromatographic and spectroscopic methods and related to heating treatments. The experimental plan focused on the following points: a) analysis of 1,2 and 1,3-diglycerides and monoglycerides content by GC and 31P-NMR methods to assess the degree of hydrolysis; b) determination of oxidative status of the samples by volatile compounds (SPME/GC-MS) and accelerated aging test (OSI); c) study of the changes in the phenolic profile upon heating by HPLC-DAD/MS and 1H-NMR.

Hydration of freeze-dried chicken breast meat was followed in the water activity range of aw = 0.12 – 0.99 by a multianalytical approach comprising of sorption isotherm, differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR). The amount of frozen water and the shape of the T2-relaxogram were evaluated at each water content by DSC and NMR, respectively. Data revealed an agreement between sorption isotherm and DSC experiments about the onset of bulk water (aw = 0.83–0.86), and NMR detected mobile water starting at aw = 0.75. The origin of the short-transverse relaxation time part of the meat NMR signal was also reinvestigated through deuteration experiments and proposed to arise from protons belonging to plasticized matrix structures. It is proved both by D2O experiments and by gravimetry that the extra protons not contributing to the water content in the NMR experiments are about 6.4% of the total proton NMR CPMG signal of meat.

L’Unità Operativa dell’Università di Bologna si è proposta di studiare, in collaborazione con il Gruppo Amadori, nuovi processi tecnologici per la produzione di preparati a base di carne avicola e valutarne gli effetti sulle caratteristiche chimico-fisiche, tecnologiche e sensoriali, nonché sulla stabilità microbiologica e la sicurezza igienica. In particolare, si è voluto mettere a confronto la tecnologia di produzione correntemente utilizzata con una nuova tipologia di lavorazione, principalmente caratterizzata da un’inversione delle fasi di cottura in forno e frittura. Un ulteriore fattore di variazione indotto nel processo produttivo riguarda le caratteristiche qualitative delle materie prime utilizzate per la preparazione dei prodotti a base di carne. Negli ultimi anni, infatti, l’industria mangimistica ha parzialmente o totalmente sostituito, nella formulazione dei mangimi, l’integrazione lipidica di origine animale con ingredienti di origine esclusivamente vegetale. Dalle considerazioni sopra esposte è sorta l’esigenza di studiare gli effetti della tecnologia di preparazione dei prodotti panati (Tradizionale vs. Innovativa) e della tipologia di carne (proveniente da animali alimentati con diete a base di grassi di origine animale o vegetale) sulle caratteristiche qualitative e sulla sicurezza dei prodotti. In questa relazione vengono riportate le metodologie di lavoro e i principali risultati ottenuti nella realizzazione del progetto dai quattro Gruppi di ricerca coinvolti.

In the last few years, the poultry industry has seen a significant decrease in the meat quality properties during the summer season. The objective of this study was to evaluate the seasonal effect (summer and winter) on turkey meat quality assessed both by conventional and Low-Resolution Nuclear Magnetic Resonance (LR-NMR) analysis. Eighty-eight breast muscles (35 winter and 53 summer) from BUT-Big 6 turkeys belonging to 16 flocks, were randomly collected from a commercial processing plant. The samples were analysed for transverse relaxation times (T2) by LR-NMR and for initial pH (15min post mortem), ultimate pH (24h post mortem) and pH after cooking, temperature at 15 min post mortem, water holding capacity (WHC) (drip loss, filter paper wetness and cooking loss), colour of raw (24h post mortem) and cooked meat and chemical composition (moisture, lipids and proteins). The results indicate that during the summer season turkey breast meat undergoes a relevant WHC decrease. Cluster analysis of the raw LR-NMR data evidenced the presence of two groups corresponding to samples harvested in each different season. Correlations between the LR-NMR signal and the conventional parameters measuring WHC were obtained by a recently proposed type of principal component regression (PCR) termed relative standard deviation PCR.

Many different ways have been devised over the years for analyzing phospholipids in soln. by 31P NMR. One promising method entails the use of the so-called CUBO solvent, a ternary mixt. of DMF, triethylamine and guanidinium hydrochloride. As this interesting system seems to have been overlooked in the literature, we present here a study on the quantification of phospholipids and lysophospholipids contained in 10 samples of com. lecithin using the CUBO/31P NMR method. Cluster anal. and principal component anal. of the NMR data showed clear differences among the samples according to the actual lecithin producer. Multivariate anal. of the chem. and phys. parameters of the samples confirmed these differences.

Quantitative 2 H NMR analysis at the natural abundance represents a well-recognized and efficient method for the identification of the origin of ethanol from different sources. An intrinsic limitation of the protocol used is the long time required, about 8 h, because of the long T 1 values of the 2 H resonances. In this work we propose the use a paramagnetic relaxation agent that significantly catalyzes the relaxation times and reduces the total time of the analysis. This agent is the macrocyclic Schiff base complex [Gd(H 2 L)(H 2 O) 3 (EtOH)](Cl) 3 · 2 EtOH (H 2 L is the [1 + 1] macrocycle derived from the condensation of 3,3 ′ -(3-oxapentane-1,5-diyldioxy)bis(2-hydroxybenzaldehyde) with 1,5-diamino-3-azamethylpentane), which is highly stable and soluble in the alcoholic solution used. Elemental analysis, IR and mass spectrometry have characterized this complex. The homogeneity of the complex and the correct Gd:Cl=1:3 ratio was established by SEM-EDS measurements. Further characterization of the paramagnetic complex has been achieved by measuring the magnetic field dependence of the 1 H longitudinal nuclear magnetic relaxation time of a 1 mM solution in CH 3 OD with a field-cycling relaxometer. The Gd III ion accommodates up to four methanol molecules in its inner coordination sphere, whose rapid exchange with the bulk provides an efficient relaxation mechanism. The addition of about 37 mg of the complex to a solution of ethanol (3.0 g) and tetramethylurea (TMU) (1.5 g) results in the reduction of the experimental time of more than 50% with a S/N ratio compatible with that required for this application.

The measure of the proton nucleus transverse relaxation rate (R2) is a good candidate for evaluating the quality of intact eggs albumen. For its succesful use some physical characteristics it depends on have been evaluated.

Biological systems often display multiexponential transverse relaxation times, diagnostic of the presence of different proton pools within the sample. A reliable representation of sample multiexponentiality can be calculated through the inversion of CPMG magnetization decays via the UPEN protocol. However, if a sample contains both liquid- and solid-like protons (as for example in muscle tissue or protein gels) CPMG cannot be used, as the solid-like signal may decay before the first echo is recorded. In these cases signal quantification is more simply attempted in the time domain, by fitting the FID to a discrete number of suitable decaying functions, provided no frequency difference exists between the signal pools. Low field spectrometers (0.47 T or less) are useful in this respect because FIDs obtained at low resolution do not usually carry frequency information. On the other side, they may suffer from very poor magnetic field homogeneity, owing to the fact that they are typically built around a permanent magnet with no shimming facilities, thus producing highly distorted FIDs whose shape can be hardly approximated by meaningful fitting functions. In this work we show that a technique known under the name of reference deconvolution in high resolution NMR can be slightly modified and used successfully in low resolution NMR for fitting highly distorted FIDs.

It is now well established that colour variations from dark, firm and dry (DFD-like) and pale, soft and exudative (PSE-like) poultry meat are associated with variations of water holding capacity (WHC) properties. The study of LR-NMR relaxation properties, and in particular the values of transverse (T2) relaxation, can give relevant information about meat WHC. To assess the existence of a direct connection between meat colour and T2 relaxation, 36 pale (L*>56), 36 normal (L* between 50 and 56) and 36 dark (L*