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A juice containing a mixture of fruits and vegetables (70% apple, 9% strawberry, 12% carrot and beet 9%) was evaluated as a potential substrate for the production of a novel probiotic beverage made with kefir grains. The effects of the kefir grains amount (1–4%, w/v) and fermentation time (12, 24 and 48 h) on the beverage composition, sensory qualities and colour were investigated. The results indicated that the amount of kefir grains have a significant effect on the content of the organic acids (lactic, acetic, citric, succinic, and malic acid), CO2 production, acidity, and viscosity and colour parameters (lightness (L*), hue (hab) and Chroma (C*ab)). Fermentation time also significantly affected all the parameters analyzed in the samples. The most suitable conditions to achieve the highest overall acceptability for the fermented beverage based on a mix of fruits and vegetable juice was: 2% (w/v) kefir inoculum during 24 h of fermentation time.

In food industry, roselle beverages and their subproducts could be functional ingredients since they are an excellent source of bioactive compounds with improved performance due to their important anthocyanins content. The aim of this study was to analyze anthocyanin content and antioxidant properties of aqueous infusions elaborated with color contrasting Hibiscus materials and design a mathematical model in order to predict color-composition relationship. Color measurements of beverages from roselle (Negra, Sudan and Rosa) were made by transmission spectrophotometry, anthocyanins quantification was determined by HPLC, and antioxidant potential was evaluated by in vitro methods (ABTS and FRAP assays). Beverages prepared with particle size minor of 250 μm presented until 4- and 2- times more anthocyanins content and antioxidant capacity respectively, in comparison to beverages prepared with powders with particle size major of 750 μm. Positive correlations among pigments composition and color parameters were found (p

Carotenoids, color and in vitro antioxidant capacity were analyzed in twenty-two genotypes of oranges produced in Spain in two consecutive seasons. The colorless carotenoids phytoene and phytofluene were also analyzed. An important influence of the genotype on the carotenoid profile was observed. In most genotypes, such profile was characterized by the predominance of xanthophylls (82.7-93.0%), except in Cara Cara, with a higher proportion of carotenes (around 70.0%). β-cryptoxanthin was the predominant carotenoid in Rohde late and Ambersweet. The samples with the lowest carotenoid contents were the ones exhibiting the lowest Trolox Equivalent Antioxidant Capacity (TEAC) and vice versa. A formula obtained by multiple regression is proposed to estimate the TEAC value from the carotenoid content. No significant correlation between TEAC values and color coordinates were obtained, suggesting that color parameters are not good predictors of TEAC values. Lastly, the samples could be classify with a high rate of success (>90%) by Linear Discriminant Analysis based on color and carotenoids.

Control of coffee quality has a great importance for being one of the most important raw materials within the international trade. The extractable composition of coffee has been studied in recent decades and the use of non-destructive methodologies is being continuously promoted. In this study, near infrared hyperspectral imaging has been applied to develop non-destructive methods for the control of extractable contents of caffeine, chlorogenic acid, total phenolics and melanoidins in coffee beans. Extractable contents and trends obtained among the different coffee types analysed are similar to those obtained previously in other studies. Moreover, modified partial least square (MPLS) regressions produced prediction models with standard errors of prediction in external validation of 12.01%, 15.61% and 17.61% for caffeine, chlorogenic acid and total phenolics, respectively. Therefore, results obtained for these three parameters indicate that NIR spectroscopy has a great potential for their control in coffee beans.

Background and Aims Winemaking generates a large quantity of grape marc that causes environmental and economic problems, which could be minimised by exploiting and adding value to these by-products. Marc is composed of seeds, skins and stems that are an important source of phenolic substances, which have antioxidant properties and potential benefits to human health. It is necessary to develop novel methods for assessing the composition of marc because conventional analyses are destructive and require lengthy preparation procedures and chemical reagents. Methods and Results Near-infrared hyperspectral imaging has been used for evaluating 27 individual phenolic substances in the components of grape marc after freeze-drying, the only sample preparation step. By applying partial least squares regression to the spectral data, values of R2 up to 0.98 were obtained even for estimating some minor compounds. Conclusions This methodology arises as an attractive alternative to analyse the phenolic composition of grape marc because of its speed and simplicity. Significance of the Study The use of this technique will allow wine producers to quickly determine the phenolic composition and decide the destination of this by-product.

The poultry meat production includes several stages. In this study, the whole process has been evaluated in order to determine the stages or processes which must be specially taken into account in the control system, and which other could be out of the routine controls. The study has been carried out in reverse by studying the relevance of every stages starting from the end of the process towards the initial point. A sequence of operations and consecutive statistical analyses has been performed to finally state the stages and/or operations that must be controlled. Based on the result of statistical studies, the plucking, gutting, washing and classifying stages should be considered Process Control Points. Air chilling and packaging stages are not considered checkpoints in the process verification system, although they should be included within the Good Hygiene Practices, since factors such as temperature, time, cleaning, disinfection or appropriate conditions of handling should be monitored.

The effect of different cold maceration times on Syrah red wines from warm climate has been evaluated. Differential colorimetry and tristimulus colorimetry were applied to colour data at different points of the vinification stage. Virtually, all the phenolic compounds showed significantly higher content in cold macerated wines, even more when longer contact time was used. Long cold macerated (LCM) wines had the significantly (P < 0.05) highest chroma values (C*ab) and lowest of lightness (L*) and hue (hab). Unexpectedly, wines submitted to short-time cold maceration (SCM) presented the lowest chroma values, even significantly inferior to that observed in traditional macerated (TM) wines. Moreover, colour changes (DE*ab) between TM and SCM were mainly quantitative (%D2L and %D2C), whereas they were also qualitative when compared TM with LCM (%D2C and %D2H). Cold maceration in warm climates characterised by common colour losses must be carefully employed because undesirable consequences on colour may occur. Consejería de Innovación, Ciencia y Empresa (Junta de Andalucía, Spain) project P-10- AGR-06331 Ministerio de Ciencia y Tecnología (Spain) project AGL2003-02972

[EN] A study of the changes of copigmentation phenomenon in wines elaborated from different varieties has been undertaken. Colorimetric measurement of Tempranillo (T) and Graciano (G) monovarietal wines, and two 80:20 blend wines: M, (grape blending T and G, co-maceration) and W (wine blending T and G, co-vinification) was performed by spectrophotometry. Significant differences (p < 0.05) were found among the color of the wines. The Graciano cv. afforded somewhat darker and more colorful wines than the other wines. The color difference values, ΔE*ab suggested that co-vinification (W) led to wines being more similar to T than the co-maceration (M). The ΔE*ab[w − c] between untreated wines – whole wines, w – and the wines diluted to eliminate copigmentation – corrected wines, c – was 14.2 CIELAB units in the initial stages of winemaking and 6.7 in the final stages. M had a greater proportion of color due to copigmentation than the monovarietal wines. Evaluation of this parameter confirms the importance of copigmentation process into wine color during the early stages of the vinification. Also, through the full spectrum, quantitative data obtained allow a visual interpretation of the changes involved. In addition, with the aging in bottle, M wines had more stable color and more different color than W wines.

Tomatoes ( Solanum lycopersicum L .) are food staples that contain high levels of lycopene (LYC), a red carotenoid thought to provide health benefits. Previous studies indicate that instrumental color measurements can be harnessed to estimate carotenoid levels in a rapid and non-destructive fashion, which offers important analytical advantages. In this investigation we have assessed the different LYC isomer contents by HPLC and the color of diverse tomato genotypes and tomato derived-products by SPR and DIA with four main purposes: 1) to compare the levels of LYC isomers in processed vs fresh tomato products, 2) to evaluate the validity of DIA and SPR to ascertain the color of these products, 3) to compare the ability of both instrumental methodologies to discriminate between the two different groups of samples, and 4) to compare the utility of both methodologies for estimating LYC levels. The results indicated that the parameters obtained by SPR and DIA were significantly correlated ( p

This study was conducted to gain insight into the influence of the chemical structure of carotenoids in the colour of orange juices. For this purpose we correlated the colorimetric information of commercially available OJ with their carotenoid content by means of multiple regressions We have concluded that the carotenoids better correlated to the hue are not necessarily the same as those mainly related to the chroma. According to our statistical analyses, the pigments mainly related to hab were zeinoxanthin, lutein and a mixture of violaxanthin isomers, whilst those mainly related to C ab ∗ were zeaxanthin, (9Z)- or (9′Z)-antheraxanthin and zeinoxanthin. These findings are very interesting for the citrus industry, since some carotenoids are used as colorants and the colour of OJ does influence the consumers’ choices.

The vinification technique called pre-fermentative cold maceration is used to enhance the anthocyans diffusion from the skins to the must, increasing the pigments extraction. For using this technique the application of low temperatures is needed. In this study, two different refrigerating methods (dry ice and cooling of grapes) have been assessed regarding the colour and the phenolic composition of the Syrah wines elaborated by applying pre-fermentative cold maceration. Results showed more intense and stable colours when grapes were previously refrigerated in cold-storage rooms, which showed higher values of chroma and more red-bluish hues. As regards phenolic composition, the cold maceration technique used yields to significant differences among the levels of phenolics, having higher levels of anthocyanins and some non-coloured phenols as flavonols in PR wines. Regarding the colour-composition relationships, it has been highlighted the importance of the co-pigments such as flavonols and cinnamic acids for classify the two groups of samples.

A methodology for food quality control, consisting of several consecutive concentric stages, is shown. It deals with a systematic and concentric study method, based on statistical results. The aim of this technique is to find the source of dissemination of a defined risk along the operations of a food process. It has been applied to the location of the presence of Listeria monocytogenes (Lm) within the different stages in a poultry slaughterhouse. By means of application of statistical techniques like chi-square test, the classifying stage, where the carcasses are greatly handled, has been identified as the main source of the Lm in the studied poultry slaughterhouse. Besides, by means of the application of logistic regression the Lm psychrotropic behavior has been confirmed.

BACKGROUND: The obtention and physicochemical characterization of an enzymatic vegetable extract (EVE) from agroindustrial wastes by a proteolytic extraction is described. The main components of EVE are nitrogen (peptides and free amino acids) and phytohormones (auxins, gibberellins, cytokinins), as functional components. The effect of EVE as fertilizer/biostimulant on several parameters of red grapes, such as colour and anthocyanins, was also evaluated. RESULTS: Its application induced high anthocyanin content with the specific induction of petunidin. Tristimulus colorimetry was applied in order to study the colour of musts. Grape juice with significant and perceptible differences in colour characteristics was obtained using EVE. The colour points were located around redder hues (hab) on the (a*b*)-plane and lightness (L*) was lower. CONCLUSION: The fertilization with biostimulant shows a promising future in the functional plant nutrition linked with an increase in the organoleptic and quality food parameters. Copyright © 2007 Society of Chemical Industry

The selection of control points is one of the most important steps in the design of a Hazard Analysis and Critical Control Points (HACCP) system. Total Count, Pseudomonas and Enterobacteriaceae are microorganisms frequently analyzed on carcasses in slaughterhouses. Its usefulness can be assessed by means of univariate and multivariate statistical methods. In this study, the use of these microbiological parameters for verification of the effect of the stages of washing with pressurized water and air chilling has been evaluated. It makes clear that multivariate statistics appears as a valuable tool to check which points and stages of the process must be controlled, demonstrating that the washing stage produces significant decreases in contamination (so it must be considered a CCP). The air chilling stage maintains the decrease in the contamination as the carcasses come out of the washing process. This is due to the control of temperature under adequate limits. The chiller air temperature would be considered a CCP in a HACCP system.

In poultry production, the washing stage takes place after the gutting stage. In the washing stage the carcasses are cleaned with pressurised water in order to remove any remains of blood, dirt and feathers on the skin, to reduce the superficial contamination, and to avoid subsequent drying in the freezers. This step is an important phase in the productive line because of its usefulness and its cost, since water is an expensive product and, sometimes, in short supply. Total Count, Pseudomonas, Enterobacteriaceae and Staphylococcus are microbial groups frequently analysed on carcasses in slaughterhouses. Their usefulness as index of microbiological quality can be assessed by means of univariate and multivariate statistical methods. In this study the influence of the washing stage on the superficial contamination of the chicken carcasses is shown with regard to the following factors: the water pressure, the amount of water and the length of the washing stage. It makes clear that multivariate statistics appears as a valuable tool for designing and implementing quality control systems, demonstrating that the contamination decreases significantly due to the effect of the washing stage and the water pressure. Time and amount of water variations do not affect the microbiological variables except for the Pseudomonas, which are affected by the amount of water and time variation but not by pressure variation. � 2004 Elsevier Ltd. All rights reserved.

The efficiency of C 30 stationary phases in the separation of carotenes and diverse hydroxycarotenoids has been the subject of several studies. However, little is known concerning their ability to resolve epoxycarotenoids isomers, whose study is of great importance due to the functions they serve and the information they can reveal concerning the processing of foods. We have concluded that C 30 columns provide an excellent separation of structural, geometrical and optical isomers of epoxycarotenoids and that the presence of 5,8-epoxide groups leads to a better shape recognition, to the extent that over 10 geometrical-optical isomers of 5,8-epoxycarotenoids have been separated. Additionally, it was observed that these carotenoids elute later than their 5,6-epoxide counterparts, albeit the latter have a longer chromophore.

We have devised a more sensible approach to estimate the carotenoid content of orange juices, which can be regarded as a model system of food with intricate carotenoid pattern. For this purpose spectroscopic information at several wavelengths and spectra of the juices and not from their carotenoid extracts were considered, such that more accurate and rapid quantitative assessments can be achieved. The wavelengths proposed on the basis of the characteristic vector method were 420, 455, 515, 545 and 610 nm or 420, 445, 510, 545 and 605 nm, depending on the measurement conditions. The correlations between the carotenoid content and the reflectances at these wavelengths were very good (R = 0.94 and 0.90, respectively). Additionally, it was demonstrated that the colour of the juices could be assessed with very good accuracy considering them. Due to its simplicity and rapidity, this method is intended to facilitate the quality control of the carotenoid content of foodstuffs in the industry and/or in the field.

10 pages, 5 tables, 4 figures., [EN] The triacylglycerol (TGs) composition of 1, 560 samples of subcutaneous fat of Iberian purebred and crossbred (iberianxDuroc) pigs reared extensively on three different feeding systems: montanera (M), cebo (C) and recebo (R), were determined. Seventeen TG species were identified by Gas Chromatography and six of them (POO, PSO, POL, OOO, SOO, OOL) accounted for 75 %. Significant differences (p < 0.01) were found for the majority of TG species among the three types of feeding. The effect of the duration of montanera on the TG composition was also explored and a significant positive correlation (p < 0.05) was found with the following TGs: OOO, SOL, OOL and OLL. After 110 days of Montanera, all the samples showed a percentage of OOO and OOL over 9.5 % and 4.5% respectively. Genotype also showed a significant effect (p < 0.01) on the TG composition. Principal Component and Linear Discriminant analyses were applied to the data set. No clear separation among the three groups (M, R and C) according to the TG profile was achieved. Only M and C groups were clearly separated according to their TG composition., [ES] Se ha determinado la composición de trigliceridos (TGs) en 1560 muestras de grasa subcutánea de cerdo ibérico puro y cruzado (ibericoxDuroc) criados en régimen extensivo en tres sistemas de alimentación: montanera (M), cebo (C) y recebo (R). Diecisiete TGs se han identificado mediante Cromatografía de Gases, y seis de ellos (POO, PSO, POL, OOO, SOO, OOL) representan el 75 %. Se encontraron diferencias significativas (p < 0.01) para la mayoría de los TGs entre los tres tipos de alimentación. También se investigó el efecto del tiempo de montanera sobre la composición de TGs, encontrándose una correlación positiva (p < 0.05) con los siguientes TGs: OOO, SOL, OOL y OLL. Tras 110 días de Montanera, todas las muestras presentaron % de OOO y OOL por encima del 9.5 % y 4.5 % respectivamente. El genotipo también mostró un efecto significativo (p < 0.01) sobre la composición de TGs. Se aplicó Análisis de Componentes Principales y Análisis Lineal Discriminantes a los datos obtenidos. No se obtuvo una buena separación entre los tres grupos de alimentación (M, R y C), sólo para los grupos de M y C se obtuvo una clara separación en base a la composición de TGs.