Stability of DON and DON-3-glucoside during baking as affected by the presence of food additives

The mycotoxin deoxynivalenol (DON) is one of the most common mycotoxins of cereals worldwide, and its occurrence has been widely reported in raw wheat. The free mycotoxin form is not the only route of exposure; modified forms can also be present in cereal products. Deoxynivalenol-3-glucoside (DON-3-glucoside) is a common DON plant conjugate. The mycotoxin concentration could be affected by food processing; here, we studied the stability of DON and DON-3-glucoside during baking of small doughs made from white wheat flour and other ingredients. A range of common food additives and ingredients were added to assess possible interference: ascorbic acid (E300), citric acid (E330), sorbic acid (E200), calcium propionate (E282), lecithin (E322), diacetyltartaric acid esters of fatty acid mono- and diglycerides (E472a), calcium phosphate (E341), disodium diphosphate (E450i), xanthan gum (E415), polydextrose (E1200), sorbitol (E420i), sodium bicarbonate (E500i), wheat gluten and malt flour. The DON content was reduced by 40%, and the DON-3-glucoside concentration increased by >100%, after baking for 20 min at 180°C. This confirmed that DON and DON-3-glucoside concentrations can vary during heating, and DON-3-glucoside could even increase after baking. However, DON and DON-3-glucoside are not affected significantly by the presence of the food additives tested.     

Ochratoxin A in wines,musts and grape juices from Spain

A survey on the occurrence of ochratoxin A (OTA) in 240 grape‐based beverages was carried out. Red and white wines from four different Spanish Designations of Origin (n = 160), musts (n = 20), grape juices (n = 10), ordinary wines (n = 20), special wines (Malaga, muscatel, sherry, vermouth, etc) (n = 20) and sparkling wines (n = 10) were assayed for OTA content using immunoaffinity column clean‐up and high‐performance liquid chromatography with fluorimetric detection (detection limit 0.05 µg l^?1). Forty‐three (17.9%) of the samples tested contained detectable levels of OTA. The overall mean OTA concentration in red and white wines of Designations of Origin was 0.30 and 0.18 µg l^?1 respectively (ranges 0.05–3.19 and 0.05–1.13 µg l^?1 respectively). The percentage of wine samples with detectable amounts of OTA was higher for red (18.3%) than for white (10%) wines. OTA was also found in two of 10 red ordinary wines (0.68 and 4.24 µg l^?1), whereas none of 10 white ordinary wines contained OTA. The mean OTA amount detected in sparkling wines was 0.44 µg l^?1 (range 0.14–0.71 µg l^?1). Two of 20 must samples contained OTA at low levels (0.08 and 0.18 µg l^?1), while none of 10 grape juice samples contained OTA. Highest amounts of OTA were found in special wines (45%), with a maximum of 15.25 µg l^?1 in a muscatel sample. Copyright © 2004 Society of Chemical Industry     

Computational Shelf-Life Dating: Complex Systems Approaches to Food Quality and Safety

Shelf-life is defined as the time that a product is acceptable and meets the consumers expectations regarding food quality. It is the result of the conjunction of all services in production, distribution, and consumption. Shelf-life dating is one of the most difficult tasks in food engineering. Market pressure has lead to the implementation of shelf-life by sensory analyses, which may not reflect the full quality spectra. Moreover, traditional methods for shelf-life dating and small-scale distribution chain tests cannot reproduce in a laboratory the real conditions of storage, distribution, and consumption on food quality. Today, food engineers are facing the challenges to monitor, diagnose, and control the quality and safety of food products. The advent of nanotechnology, multivariate sensors, information systems, and complex systems will revolutionize the way we manage, distribute, and consume foods. The informed consumer demands foods, under the legal standards, at low cost, high standards of nutritional, sensory, and health benefits. To accommodate the new paradigms, we herein present a critical review of shelf-life dating approaches with special emphasis in computational systems and future trends on complex systems methodologies applied to the prediction of food quality and safety.     

Determination of the optical depth of a DI diesel spray

The optical depth is responsible of limiting the optical diagnostic using visible wavelength in the sprays. This paper proposes to measure the optical depth directly in a real Diesel spray through line-of-sight laser extinction measurements. This easily reproducible method which does not require expensive or complex optical techniques is detailed and the measurement procedure is presented in this paper. As diesel sprays are mostly optically thick, the measurements in the denser region are not reliable and a fuel concentration model has been used to derive the results to the entire spray. This work provides values of SMD at different distance from the nozzle tip depending on the specific parameters like injection pressure or discharge density. The values extracted from a combined experimental/computational approach have been compared to PDPA measurements under the same testing conditions. The results have shown that the maximum optical depth was higher than 10 and that an increase of the injection pressure led to higher τ values. The SMD values appeared to be below the results measured by the PDPA and the droplet diameter showed to be the main responsible of the optical depth of the jet under the tested conditions.     

A Nondestructive Methodology for the Study of Colored Enamels: Insights into Manufacturing and Weathering Processes

We studied ancient enamels on gilded copper from a collection of archeological horse harness pendants of the Museo Instituto Valencia de Don Juan (Madrid, Spain) to test the benefits of a new, nondestructive analytical methodology based on chemometric analysis (i.e., Principal Component Analysis, PCA) on micro‐ATR‐FTIR spectral data and chemical quantification using SEM‐EDS. The novelty of this approach was threefold: (i) PCA allowed the discrimination of the different harness pendants of known origin and attributed to the 14th and 15th centuries according to the chemical complex composition, nanostructure, glass weathering, and/or coloring mechanisms of each colored enamel, separately (i.e., red, purple, blue, and white), (ii) it is a cheap, easily available and nondestructive methodology that enables us to (iii) draw archeological conclusions about the quality of the manufacturing process, reassess the chronology of these objects and attempt to attribute them to different workshops according to the different traditional recipes identified. In particular, the enamels were made of alkali and/or alkaline earth lead‐glass with a wide range of chemical compounds in the form of pigments or opacifiers. Two types of coloring mechanisms were identified, colloidal particles such as copper‐ruby for red enamels, and ionic mechanisms such as Fe(II) and Co(II) to achieve a blue pigments; Mn(III) in the purple pigment; and two kind of white enamels were identified, i.e., tin oxide as an opacifier and uranium oxide. In addition, we established the reason for the poor state of conservation of some of the enamels by means of the identification of depolymerization and ion exchanges, well‐known harmful effects of glass weathering, and finally a chronology was assigned for some of these pieces according to the enamel composition.     

Polyphenolic contents in Citrus fruit juices: authenticity assessment

The contents of 49 polyphenols in sweet orange, tangerine, lemon and grapefruit juices from 18 cultivars grown in Spain were determined by reversed-phase high-performance liquid chromatography with photodiode array detection. Citrus polyphenolic profiles consist of 81–97 % of flavanones, 0.3–13.6 % of flavones, 0.1–6.0 % of flavonols, 0.6–9.6 % of hydroxycinnamic acids and 0.2–0.4 % of coumarins (only found in grapefruit juices). Several markers that allow to distinguish with practical certainty grapefruit and lemon juices between them and from the other Citrus species are reported. Each of these markers is a reliable and useful tool to detect juice adulteration. Grapefruit juice markers were naringenin-7-O-neohesperidoside, naringenin-7-O-neohesperidoside-4′-O-glucose, naringenin-O-hexosylhexoside, hesperetin-7-O-neohesperidoside, naringenin-O-rhamnosylmalonylhexoside, isosakuranetin-7-O-neohesperidoside, hesperetin-7-O-rutinoside, apigenin-6-C-hexoside-O-hexoside, apigenin-7-O-neohesperidoside and scopoletin-O-hexoside. Lemon juice markers were eriodictyol-7-O-rutinoside-4′-O-glucoside, eriodictyol-7-O-rutinoside, diosmetin-6,8-di-C-glucoside, diosmetin-8-C-glucoside, luteolin-7-O-rutinoside, diosmetin-6-C-glucoside and diosmetin-6,8-di-C-hexosideacylhexoside. The markers naringenin-O-hexosylhexoside, apigenin-6-C-hexoside-O-hexoside, scopoletin-O-hexoside, diosmetin-8-C-glucoside and diosmetin-6,8-di-C-hexosideacylhexoside were detected, characterized and quantitatively determined in grapefruit and lemon juices for the first time by our research group, as far as the authors know. Classification models provided by LDA and PLS-DA correctly identify all sweet orange and tangerine juices. Moreover, PLS regression model determines the percentage (10–70 %) of tangerine juice used to adulterate sweet orange juice with a suitable confidence interval (RMSEP = 7 %).     

Oxygenated compounds derived from glycerol for biodiesel formulation: Influence on EN 14214 quality parameters

The methyl esters of fatty acids (biodiesel) obtained via transesterification of vegetable oils or animal fats are an alternative to current fossil fuels. A large amount of glycerol as a by-product is generated in this process and new applications for this surplus need to be found. Thus, the transformation of glycerol into branched oxygen-containing compounds could be an interesting solution to provide an outlet for increasing glycerol stocks. In this work, several oxygenated compounds, obtained by transformation of glycerol via etherification, esterification and acetalisation, have been assessed as components for biodiesel formulation. Different quality parameters have been evaluated following the procedures listed in the EN 14214 European Standard for biodiesel specifications. These parameters have been correlated with the amount and chemical nature of oxygenated derivate present in the biodiesel. The best performance as component for biodiesel formulation has been achieved by the mixture of ethers produced via etherification of glycerol with isobutylene. The addition of these compounds has not only improved the low-temperature properties of biodiesel (i.e. pour point and cold filter plugging point) and viscosity, but also did not impair other important biodiesel quality parameters analyzed. Although most of the studied oxygenated derivates do not significantly improve any biodiesel property, they do not exert a significant negative effect either. Furthermore, all of them allow an enhancement of overall yield in the biodiesel production. Nevertheless, further improvement could be addressed with a better purification to reduce the presence of non-desired impurities such as di-isobutylenes and unreacted acetic acid, which have a negative influence especially in acid number and oxidation stability.