Technical note: Rapid method for determination of amino acids in milk.

A rapid method for measurement of amino acids in milk was developed and validated. The method included a first step of milk protein hydrolysis, followed by the derivatization and separation of amino acids by HPLC. Six combinations of hydrolysis agent and temperature-time conditions were compared with a reference method; derivatization procedures as well as HPLC separation were improved. Hydrolysis of milk samples with 6 N HCl at 160 degrees C for 60 min resulted in no significantly differences compared with the reference method but allowed the analysis of a greater number of milk samples in a short time. In addition, this method was characterized by high precision, low repeatability uncertainty, and high accuracy for all amino acids evaluated; the recovery mean value of the single amino acids was 98.38%. The proposed method is, therefore, accurate, simple, rapid, and suitable for large numbers of milk samples

Effect of Different Cooking Treatments on the Residual Level of Nitrite and Nitrate in Processed Meat Products and Margin of Safety (MoS) Assessment

Nitrite and nitrate are well-known food additives used in cured meats and linked to different food safety concerns. However, no study about the possible effect of cooking treatment on the residual level of these compounds before consumption is available. In this work, 60 samples of meat products were analyzed in order to evaluate the variation in residual nitrite and nitrate level after baking, grilling and boiling. The analyses by ion chromatography demonstrated that meat cooking leads to a decrease in nitrite and an increase in nitrate residual levels in the final products. Meat boiling caused an overall decrease in two additives’ concentration, while baking and particularly grilling caused an increase in nitrate and, in some cases, nitrite as well. Some regulatory aspects were also considered, such as the possibility of revising the legal limit of nitrate from the actual 150 mg kg−1 to a more cautious 100 mg kg−1. Indeed, several meat samples (bacon and swine fresh sausage) resulted in a higher nitrate concentration than the legal limit after cooking by grilling (eleven samples) or baking (five samples). Finally, the Margin of Safety evaluation demonstrated a good level of food safety, all values being higher than the protective threshold of 100

Advanced Analysis Techniques of Food Contaminants and Risk Assessment—Editorial

No one wants to eat food that is unsafe and that can put their health at risk in any way or form [...

A Service of zbw Technological Capabilities and Patterns of Cooperation of UK Firms: A Regional Investigation Technological Capabilities and Patterns of Cooperation of UK Firms: A Regional Investigation ABSTRACT Technological Capabilities and Patterns of

Standard-Nutzungsbedingungen: Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden. Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen. Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte

Determination of Sulphiting Agents in Raw and Processed Meat: Comparison Between a Modified Monier-Williams Method and the Direct Analysis by Ion Chromatography with Conductometric Detection

Sulphiting agents are a class of compounds that are used as preservatives since they release SO2 in food. Regarding meat products, the legislation restricts the use of these food additives, due to some toxic effects that they may have in humans. The most employed analytical procedure for the determination of sulphiting agents in foodstuffs is the Monier-Williams (M-W) method, but the reliability of this method was called into question by several authors. In this work, the M-W method was modified by replacing both the distillation unit to shorten the extraction time (from hours to 5 min) and the final titration with a chromatographic separation followed by conductometric detection of sulphate ion (m-M-W/IC-CD). This method was then validated, and the performance parameters were compared with those of the method based on the direct analysis of sulphite ion by ion chromatography with conductometric detection (DIC-CD). Linearity, accuracy at 40 and 80 mg kgâ\u88\u921 of SO2 and measurement uncertainty resulted comparable. Accuracy at 10 mg kgâ\u88\u921 of SO2 resulted higher for the m-M-W/IC-CD method, but this parameter could be influenced by traces of other sulphur-containing compounds that may be present in meat. The limit of determination of the m-M-W/IC-CD method was slightly higher than that obtained by the DIC-CD method. Finally, through spiking tests, it was proved that sulphide, 2-methyl-3-furanthiol and l-methionine cause â\u80\u9cfalse-positiveâ\u80\u9d responses, by using M-W-based methods

Survey of benzoic acid in cheeses: contribution to the estimation of an admissible maximum limit

Benzoic acid and its salts are commonly used additives in the food industry. Their use is not allowed in dairy products even though they can be found naturally. In this work, 100 cheese samples were tested to establish the maximum concentration that can be considered as "natural" and, therefore, permitted in cheeses. Analyses were carried out by a validated ion chromatography method and "positive" samples were confirmed by two other HPLC methods. Benzoic acid concentrations higher than the method LOQ (8.8 mg kg -1) were found in 18 samples, ranging from 11.3 to 28.7 mg kg -1, with a mean value of 20.5 mg kg -1. Taking into account the distribution of benzoic acid concentrations observed in "positive" samples, it is plausible to estimate a maximum admissible limit of 40.0 mg kg -1 for benzoic acid in cheese. Below this value, samples can be considered "compliant". © 2011 Copyright Taylor and Francis Group, LLC

Beta emitter radionuclides (90Sr) contamination in animal feed: validation and application of a radiochemical method by ultra low level liquid scintillation counting

⁹⁰Sr is considered as a dangerous contaminant of agri-food supply chains due to its chemical affinity with Calcium, which makes its absorption in bones easy. ⁹⁰Sr accumulation in raw materials and then in final products is particularly significant in relationship to its ability to transfer into animal source products. The radionuclides transfer (¹³⁷Cs and ⁹⁰Sr) from environment to forages and then to products of animal origin (milk, cow and pork meats) was studied and evaluated in different studies, which were carried out in contaminated areas, from Chernobyl disaster until today. In the present work, the development and validation of a radiochemical method for the detection of ⁹⁰Sr in different types of animal feed, and the application of this technique for routinely control activities, are presented. Liquid scintillation counting was the employed analytical technique, since it is able to determine very low activity concentrations of ⁹⁰Sr (<0.01 Bq kg^–1). All samples analysed showed a 90Sr contamination much higher than method detection limit (0.008 Bq kg^–1). In particular, the highest mean activity concentration was registered in hay samples (2.93 Bq kg^–1), followed by silage samples (2.07 Bq kg^–1) and animal feeds (0.77 Bq kg^–1). In fact, all samples were characterized by ⁹⁰Sr activity concentrations much lower than reference limits. This notwithstanding, the necessity to monitor these levels was confirmed, especially considering that ⁹⁰Sr is a possible carcinogen for human

Technological capabilities and patterns of innovative cooperation of firms in the UK regions

This paper focuses on the relationship between firms' technological capabilities and different forms of cooperation for innovation, paying specific attention to the role of regional location of the firm. The findings, based on the Fourth UK Community Innovation Survey (CIS4), show that cooperation within business groups, vertical cooperation with customers and suppliers, and horizontal cooperation with universities turn out to be significantly associated with firms' technological capabilities. However, it is found that the analysis for the UK as a whole masks stark regional differences in terms of the relationship between local and non-local collaborative linkages and firms' technological capabilities and competences

Firm capabilities and cooperation for innovation: evidence from the UK regions

This chapter focuses on the relationship between firms’ technological competencies and capabilities and different forms of cooperation for innovation by combining the analysis of both micro and meso levels, i.e. the level of the firm and of the geographical region. Our findings, based on the Fourth UK Community Innovation Survey (CIS), provide new insights regarding the relationship between cooperative linkages for innovation and firms’ technological status. Firstly, the distinction between competencies and capabilities adopted in this chapter seems appropriate for going beyond the rather simplistic dichotomy of ‘innovative’ versus ‘non-innovative’ firms commonly used in interpreting CIS data. Secondly, we find that the analysis for the UK as a whole masks stark regional differences in terms of intra- and extra-region collaborative linkages and firms’ technological status

Indagine sull’avvelenamento da rodenticidi anticoagulanti in Puglia e Basilicata (Italia)

This study evaluates the presence of anticoagulant rodenticides in animals with a diagnosis of suspected poisoning and in bait samples. The survey was carried out from 2010 to 2012, in 2 regions of South Italy (Puglia and Basilicata) on 300 organs of animals and 90 suspected bait samples. The qualitative and quantitative analyses were conducted using an analytical method based on high-performance liquid chromatography (HPLC) with fluorimetric detection (FLD) for the simultaneous determination of 8 anticoagulant rodenticides (bromadiolone, brodifacoum, coumachlor, coumafuryl, coumatetralyl, difenacoum, flocoumafen, and warfarin). The presence of anticoagulant rodenticides was detected in 33 organs of animals (11% of the total) and 6 bait samples (7% of the total). The most commonly detected compound was coumachlor (47% of 39 positive samples) followed by bromadiolone (24%), and brodifacoum (11%). The species mostly involved in anticoagulant rodenticide poisoning were dogs and cats. This study emphasizes the relevance of the determinations of anticoagulant rodenticides in cases of suspected poisoning in veterinary practice