Luca Maria Chiesa

Moulds and ochratoxin A on surfaces of artisanal and industrial dry sausages.

The use of moulds as a seasoning for sausage can have both desirable and undesirable consequences. The desirable consequences are the creation of a successful product that appeals to consumers. The undesirable consequences are due to the growth of undesirable moulds that produce highly toxic secondary metabolites referred to as mycotoxins. The aim of the paper was to investigate the presence of moulds producing ochratoxin A (OTA) on the surface of sausages from northern Italy. A total of 757 mould strains were isolated from sausage casings. The most frequently identified species were Penicillium nalgiovense, Penicillium oxalicum, Eurotium amstelodami, Penicillium olsonii, Penicillium chrysogenum, Penicillium verrucosum, Penicillium viridicatum, and Eupenicillium crustaceum. Aspergillus ochraceus was detected in only one production lot. Approximately 45% of these samples were positive for the presence of OTA. On the casings of the investigated sausages, the lowest and highest OTA values were 3 and 18 microg/kg, respectively. The OTA concentration was reduced to below the limit of detection (LOD) by brushing and washing the sausages prior to sale. From these data it appears that the presence of OTA on the surface of sausage (on the casings) is not indicative of any health risk for human consumption of sausage, since OTA was not identified inside the dry meat.

A headspace solid-phase microextraction gas-chromatographic mass-spectrometric method (HS-SPME–GC/MS) to quantify hexanal in butter during storage as marker of lipid oxidation

A method using headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC/MS) was developed and validated for the extraction and quantification of hexanal content in butter (at ngg(-1) level) during storage at 4°C. The variability of hexanal content among seasons of production and the influence of high extraction temperature on ex-novo formation of hexanal were also evaluated. The HS-SPME conditions were optimised and analytical parameters of the method (linearity, accuracy, and precision) demonstrate its usefulness. The reproducibility and accuracy of the quantitative analysis was assured by the use of D(12)-hexanal as internal standard. For the applications, the headspace was extracted using CAR/PDMS fiber for 180min at 4°C. Hexanal contents in samples during all storage period (shelf-life) and from butters produced in different seasons were analysed. Butter samples at the end of shelf-life and samples produced in August showed highest values of hexanal, confirming that the temperature both in storage and distribution phases represents a critical factor to maintain the quality of butter.

Effect of dietary carnosic acid on the fatty acid profile and flavour stability of meat from fattening lambs

Thirty-two lambs were fed with barley straw supplemented by a concentrate alone, or a concentrate enriched with either vitamin E (VITE006: 0.6 g kg(-1) feed concentrate) or carnosic acid (CARN006: 0.6 g kg(-1) feed concentrate; or CARN012: 1.2 g kg(-1) feed concentrate). In order to elucidate the influence of the dietary supplementation of carnosic compared with a reference diet antioxidant (vitamin E), the animals were slaughtered and the longissimus thoracis were lyophilised to determine the FAs profile and the phenolic compounds. In addition, longissimus lumborum slices were stored in a modified atmosphere package for 3 days and then grilled to determine volatile compounds. Dietary carnosic acid did not modify the FAs profile, but had a clear effect on the production of volatile compounds, in a dose-dependent manner. These results have implications for the food industry, since dietary carnosic acid seems to extend the shelf life of lamb meat.

Melissopalynological and Volatile Compounds Analysis of Buckwheat Honey from Different Geographical Origins and Their Role in Botanical Determination

Volatile organic compounds (VOCs) have been proposed as one of the main factors for differentiating honeys from different botanical/floral origins. In this work, we investigated the volatile profile of honeys, commercially labeled as buckwheat honeys, from the Alps and its relationship with melissopalynological investigation. The results showed that buckwheat honey samples that contained, to different extents, buckwheat pollen grains on melissopalynological analyses showed similar VOCs profiles, distinguishing them from the other honey floral types analyzed. Among VOCs identified, 3-methylbutanal, butanoic acid, pentanoic acid, and isovaleric acid were considerably greater in the buckwheat honey samples from the Alps. Other compounds were identified only in the honeys containing buckwheat pollen grains such as 3-methyl-2-buten-1-ol, 2-butanone, 2-hydroxy-3-pentanone, 4-methylpentanoic acid, 4-pentanoic acid, butanal, 2-methylbutanal, pentanal, dihydro-2-methyl-3(2H)-furanone, 5-methylfurfural, and cis-linalool oxide. These compounds give to buckwheat honey its characteristic aromatic and organoleptic properties and may be considered interesting as potential “variety markers” for botanical determination.

Determination of veterinary antibiotics in bovine urine by liquid chromatography-tandem mass spectrometry.

A follow-up of antibiotics (tetracyclines, fluoroquinolones, cephalosporins, penicillins and amphenicols) in the bovine urine is important for two reasons: to understand if they are still present in organism, and whether their occurrence in urine might be considered as an environmental risk. A validated HPLC-MS/MS method (Decision 2002/657/EC) for antibiotics determination in bovine urine was developed. CCα and CCβ were in the range of 0.58-0.83 and 0.55-1.1 ng mL(-1), respectively. Recoveries were 92-108%, with inter-day repeatability below 12%. Analysis of bovine urine revealed frequent presence of tetracyclines, which was related with animals age. The cause, most presumably, might be found in different therapeutic protocols applied for veal calves and young bulls enrolled in this study. Most abundant was oxytetracycline with highest level in veal calves (1718 ng mL(-1)) vs. young bulls (2.8 ng mL(-1)). Our results indicate the necessity of antibiotics monitoring in bovine urine before animals undergo further processing in the food industry.

Different Fibres for the Analysis of Volatile Compounds in Processed Meat Products by Solid Phase Micro-Extraction (SPME)

L.M. Chiesa1,∗, S. Soncin1, P.A. Biondi2, P. Cattaneo1 and C. Cantoni1 1Laboratory of Food Inspection, Department of Veterinary Sciences and Technologies for Food Safety, Faculty of Veterinary Medicine, University of Milan, Milan, Italy; 2Laboratory of Food Biochemistry, Department of Veterinary Sciences and Technologies for Food Safety, Faculty of Veterinary Medicine, University of Milan, Milan, Italy ∗Correspondence: E-mail: luca.chiesa@unimi.it

HS-SPME-GC/MS analysis of the volatile compounds of Achillea collina : Evaluation of the emissions fingerprint induced by Myzus persicae infestation

A Headspace Solid-phase Microextraction (HS-SPME) method combined with Gas Chromatography-Mass Spectrometry (GC/MS) was developed and optimized to extrat and analyze the volatile compounds of aerial parts of Achillea collina Becker ex Rchb. and to investigate the effect of the phlem feeding aphid Myzus persicae Sulzer on the Volatile Organic Compounds (VOCs) emitted by the infested plants. The extraction of 1 g of powdered freeze dried plant samples for 120 min at 30°C using divinylbenzene-carbowax-polydimethylsiloxane (DVB/CAR/PDMS) fiber showed the highest area counts for the majority of the volatile compounds. Overall, 62 and 80 volatile compounds were detected in control and infested plant samples respectively. In A. collina infested plants, we observed a great increase in both monoterpenes and sesquiterpenes fractions. Several changes among alcohols also occurred, particularly regarding Z-3-hexen-1-ol, E-3-hexen-1-ol and E-2-hexen-1-ol proposing these compounds as herbivore-induces plant volatiles (HIPVs). New perspective for agricultural practice may derive from the opportunity to identify novel herbivores-induced plant VOCs active as plant protection agents.

Evidence for false-positive results for Boldenone testing of veal urine due to faecal cross-contamination during sampling

European Directive 96/22/EC, which controls veterinary residues in animals, does not permit the presence of synthetic growth promoters in products of animal origin or in livestock. Boldenone is categorized in class A3 (growth promoters — steroids) and is thus a banned substance. Testing of veal urine for banned substances is part of the European Union statutory programme for animals going into the food chain. In relation to this monitoring, three studies were conducted to investigate the apparent presence of the banned growth promoter boldenone in veal urine, which was suspected as being caused by interference from faecal contamination of the sample. In the first study, urine samples were collected at different times (time 0 and after 30 min) using (1) a conventional zoonotechnical apron and (2) a technique designed specifically to avoid faecal contamination (‘kettle’). This resulted in samples that were, respectively, positive and negative for the presence of α-boldenone (α-BOL). In a second study, urine samples negative to α-BOL were collected from eight veal calves, but became positive after deliberate faecal contamination. In a third study, data obtained from the Italian RNP (Residual National Program) indicated that 18.1% of 3295 urine samples collected using the zootechnical apron were positive for α-BOL and 2.1% for β-boldenone (β-BOL), whilst of 902 samples collected using the kettle, β-BOL was not detected in any samples and only 0.2% were positive to α-BOL, in concentrations lower than 2 ng ml−1. These results further support the supposition that faecal contamination of the urine during sample collection can lead to false-positive results during boldenone analysis.

Secondary metabolites and antioxidant capacities of Waldheimia glabra (Decne.) Regel from Nepal.

BACKGROUND The phenolic content, volatile compound fingerprint and antioxidant capacity of Waldheimia glabra (Decne.) Regel (Asteraceae), a wild plant from the Himalayan mountains used in Sherpa religious rituals and in traditional medicine, were determined for the first time to investigate its suitability as a source of natural antioxidants. RESULTS The total phenolic content and antioxidant capacity of dried and powdered plants from two different altitudes (5000 and 5200 m above sea level) in Khumbu Valley, Nepal were estimated by the Folin-Ciocalteu and 2,2-diphenyl-1-picrylhydrazyl radical methods respectively. The volatile organic compound (VOC) fingerprints from leafing plants (in vivo and in situ VOC sampling) and from dried plant samples were evaluated by headspace solid phase microextraction. The results indicated that W. glabra was a good source of phenolics with antioxidant properties. A correlation between total phenolic content and antioxidant capacity was found (r² = 0.9111). Seychellene, a volatile compound that characterises patchouli oil, was detected for the first time in a species of the Asteraceae family. CONCLUSION Waldheimia glabra was proved to be a good source of antioxidants, partially supporting its traditional uses. Further studies aimed at deepening knowledge on W. glabra bioactivity and its possible uses will be of interest, considering the lack of proper scientific awareness regarding these aspects.

Secondary Metabolite Profile, Antioxidant Capacity, and Mosquito Repellent Activity of Bixa orellana from Brazilian Amazon Region

The Brazilian flora was widely used as source of food and natural remedies to treat various diseases. Bixa orellana L. (Bixaceae), also known as annatto, urucu, or achiote, is a symbol for the Amazonian tribes that traditionally use its seeds as coloured ink to paint their bodies for religious ceremonies. The aim of this study was to investigate the volatile organic compounds (VOCs) profile of B. orellana fresh fruits (in vivo sampled), dried seeds, wood, bark, and leaves analyzed with Headspace solid-phase microextraction coupled with gas chromatography and mass spectrometry. A screening on phenolic content (the Folin-Ciocalteu assay) and antiradical activity (DPPH assay) of seeds was also conducted. In addition, the repellent properties of seed extracts against Aedes aegypti L. were investigated. Volatile compounds detected in B. orellana samples consisted mainly of sesquiterpenes, monoterpenes, and arenes: α-humulene is the major volatile compound present in seed extracts followed by D-germacrene, γ-elemene, and caryophyllene. B. orellana proved to be a good source of antioxidants. Preliminary data on repellency against A. aegypti of three different dried seed extracts (hexane, ethanol, and ethanol/water) indicated a significant skin protection activity. A protection of 90% and 73% for hexane and ethanol/water extracts was recorded.