Francisco Artés - Academia.edu (original) (raw)

Papers by Francisco Artés

Nutricion Clinica y Dietetica Hospitalaria

Combined effect of heat treatment, UV-C and superatmospheric oxygen packing on phenolics and brow... more Combined effect of heat treatment, UV-C and superatmospheric oxygen packing on phenolics and browning related enzymes of fresh-cut pomegranate arils

Food Microbiology, 2015

The inactivation of Escherichia coli, S. Enteritidis and Listeria monocytogenes after UV-C radiat... more The inactivation of Escherichia coli, S. Enteritidis and Listeria monocytogenes after UV-C radiation with 0, 2.5, 5, 7.5, 10 and 15 kJ UV-C m(-2) on fresh-cut kailan-hybrid broccoli was explored. Inactivation did not follow linear kinetics. Hence, it was modelled by using the Weibull distribution function, obtaining adjusted R(2) values higher than 94%, indicative of the accuracy of the model to the experimental data. The UV-C doses needed to reduce 1 log cycle the E. coli, S. Enteritidis and L. monocytogenes counts were 1.07, 0.02 and 9.26 kJ m(-2), respectively, being S. Enteritidis the most sensitive microorganism to UV-C radiation while L. monocytogenes was the most resistant. According to experimental data, UV-C doses higher than 2.5 kJ m(-2) did not achieve great microbial reductions. No differences in the growth behaviour of these microorganisms was observed in the treated samples stored under air conditions at 5, 10 and 15 °C, compared to the control. Conclusively, low UV-C doses are effective to reduce E. coli, S. Enteritidis and L. monocytogenes populations in fresh-cut kailan-hybrid broccoli keeping such counts stable during shelf life at 5-10 °C. The current study provides inactivation models for these foodborne pathogens that can be used in microbial risk assessment.

Postharvest Biology and Technology, 2013

ABSTRACT The effects of neutral electrolysed water (NEW), ultraviolet light C (UV-C) and superatm... more ABSTRACT The effects of neutral electrolysed water (NEW), ultraviolet light C (UV-C) and superatmospheric O2 packaging (HO), single or combined, on the quality of fresh-cut kailan-hybrid broccoli for 19 days at 5 °C were studied. As controls, washing with water and sanitation with NaClO were both used. Electrolyte leakage, sensory, microbial and nutritional quality changes throughout shelf-life were studied. At day 15, the combined treatments achieved lower mesophilic and psychrophilic growth compared to the single ones. Single treatments produced higher ascorbate peroxidase (APX) reductions just after its application, while superoxide dismutase (SOD) showed the opposite behaviour. After 5 days at 5 °C, a great increase of APX and guaiacol peroxidase (GPX) activity was observed, NEW + UV-C + HO and HO-including treatments achieving the highest and the lowest APX increases, respectively. UV-C-including treatments produced the highest α-linolenic acid (ALA) decreases ranging 35–38% over control contents on the processing day. NEW-including treatments greatly reduced, throughout shelf-life, ALA and stearic acid (SA) content by 27–44% and 31–61%, respectively. Total phenolic content and antioxidant capacity (1415 mg ChAE kg−1 fw and 287 mg AAE kg−1 fw, respectively) remained quite constant during shelf-life. In general, the treatments and their possible combinations seem to be promising techniques to preserve, or even enhance, the quality of fresh-cut kailan-hybrid broccoli and, probably, other vegetables.

Journal of the Science of Food and Agriculture, 2006

The kinetics of polyphenol oxidase (PPO, EC 1.14.18.1) with respect to oxygen concentrations from... more The kinetics of polyphenol oxidase (PPO, EC 1.14.18.1) with respect to oxygen concentrations from 5 to 100% using chlorogenic acid (CGA) as substrate was examined. In vitro mushroom PPO activity was determined by measuring the consumption of oxygen during the oxidation reaction. A differential Michaelis-Menten model was fitted to the obtained total depletion curves. The product concentration as well as the concentration of oxygen had a clear inhibitory effect on the reaction rate. However, the inhibitory effect of oxygen was more evident at low product concentration. A linear mixed inhibition model that considered both the product (oxidised CGA) and oxygen as inhibitors was developed. A model with the product as a competitive inhibitor and oxygen as an uncompetitive inhibitor was the most appropriate to explain the reaction kinetics. The values of the inhibition constants calculated from the model were 0.0032 mmol L −1 for K m (Michaelis-Menten constant related to oxygen), 0.023 mmol L −1 for K mc (constant for competitive inhibition due to the product), 1.630 mmol L −1 for K mu (constant for uncompetitive inhibition due to oxygen) and 1.77 × 10 −4 mmol L −1 s −1 for V max (maximum reaction rate). The results indicate that superatmospheric oxygen concentrations could be effective in preventing enzymatic browning by PPO.

Journal of the Science of Food and Agriculture, 1995

The fatty acid composition of the seed oils of six pomegranate (Punica granatum L) cultivars was ... more The fatty acid composition of the seed oils of six pomegranate (Punica granatum L) cultivars was qualitatively and quantitatively determined by gas chromatography. The seeds contained oil in the range 51 152 mg kg 1 dry matter. Intervarietal differences in fatty acid composition were demonstrated (fatty acid esters as % (w/w) total fatty acid esters. Sour varieties had the highest while sour-sweet varieties had the lowest oil content. Eleven fatty acids were identified. In all varieties, the predominant fatty acids were linoleic (25 2-38.6%) and oleic acid (24'8-35.5%) followed by palmitic (18.2 22.6'%), stearic (6'9 l0'4"A) and linolenic acict (0.6 9.9%). To a lesser extent arachidic (1.1-3.4%) and palmitoleic acid (0.2 2.7"A) were also found in all varieties. Lauric, myristic, behenic and lignoceric acids were rarely detected. As far as we know linolenic (18:3), arachidic (20:0), behenic (22:0) or lignoceric (24:0) acids have not been previously reported in the seed oils of edible pomegranate varieties. Lignoceric acid has not previously been found in pomegranate seed oil.

Journal of the Science of Food and Agriculture, 2013

Fresh-cut arils were subjected to hot water dipping at 55 C for 30 s, UV-C light (4.54 kJ m À2 ) ... more Fresh-cut arils were subjected to hot water dipping at 55 C for 30 s, UV-C light (4.54 kJ m À2 ) and passive modified atmosphere packaged or high oxygen (initial 90 kPa O 2 ) active modified atmosphere packaging treatments. Arils were stored at 5 C and 90% relative humidity up to 14 days. Superoxide dismutase, catalase, peroxidase and polyphenol oxidase activities as well as individual and total phenolics compounds and anthocyanins were assessed. All treatments reduced superoxide dismutase activity. However, UV-C and high oxygen, alone or combined, resulted in arils with the highest superoxide dismutase activity. UV-C þ high oxygen treated arils also showed the lowest reduction in catalase activity. Hot water was effective suppressing polyphenol oxidase activity while peroxidase activity increased. All treatments involving high oxygen and/or UV-C kept high anthocyanins and especially phenolic content. Results showed that the decrease of superoxide dismutase and catalase and the increase in peroxidase and polyphenol oxidase might induce quality loss and browning development. The combination of UV-C and high oxygen preserved superoxide dismutase and catalase, had lower values of peroxidase and polyphenol oxidase and maintained the concentration of antioxidant compounds. These treatments seem to be a good option to improve and extend the shelf life of fresh-cut arils.

Journal of Food Science, 2002

Fennel was washed on the butt-end cut with ascorbic (1%) and citric (5%) acids and packed in poly... more Fennel was washed on the butt-end cut with ascorbic (1%) and citric (5%) acids and packed in polypropylene (PP) baskets sealed with PP film to generate a modified atmosphere. As a control, perforated PP was used. Storage conditions were 14 d at 0 8C followed by 4 d in air at 15 8C. Chemical and sensory quality attributes were monitored. No browning of external leaves developed. Modified atmosphere of 16 to 17% O 2 and 3 to 4% CO 2 was able to inhibit browning of the butt-end cut, the main factor for keeping quality of fennel, but treatments with antioxidants did not. In all treatments, green color and firmness decreased, although under modified atmosphere the best results for keeping fennel quality were found.

Journal of Food Quality, 1993

Food Science and Technology International, 2010

Elaboration of minimally processed or fresh-cut vegetables requires a quick and reliable method f... more Elaboration of minimally processed or fresh-cut vegetables requires a quick and reliable method for detection of bacterial contamination over the recommended limits. PCR-based methods fulfil these requirements, but amplification from DNA preparations of the food product is often hampered due to inhibiting substances. The purpose of this study was to develop a fast quantitative PCR (qPCR)-based method for aerobic bacterial enumeration in fresh-cut lettuce, using as reference the centrifugation water (CW) that comes up during processing instead of the food matrix itself. Comparisons between bacterial numbers on lettuce leaves before processing and bacterial numbers in the CW both for naturally occurring bacterial populations and for artificially inoculated lettuce were performed. On an average, 35% of the natural bacterial population and 64% of inoculated bacteria were recovered in the CW. Bacterial number in CW was proportional to initial lettuce contamination suggesting that measures on CW allow a narrow estimation of lettuce contamination. In qPCR, a 23S rDNA region was amplified from bacterial DNA present in the CW, followed by melting peak analyses and quantification. Enumeration of cell number by qPCR did not differ significantly from plate assay and might therefore replace it. The proposed protocol, which includes sample taking, DNA extraction and qPCR from the CW can be performed within less than 5 h. The resulting quantification might be used as a proxy of initial lettuce contamination, allowing direct intervention measures before fresh-cut commodity is shipped from the factory.

Food Research International, 2013

ABSTRACT Glucosinolates are sulphur-containing compounds present in Brassica species that are hyd... more ABSTRACT Glucosinolates are sulphur-containing compounds present in Brassica species that are hydrolyzed by the plant enzyme myrosinase to isothiocyanates (ITC), which have previously reported chemopreventive properties. In vivo, ITC are metabolized and excreted in urine as mercapturic acids. A cross-over-design study of 7 subjects after ingestion of 200-g raw or microwaved kailan-hybrid broccoli was conducted. Total ITC equivalents in the vegetable, urine and blood samples were determined by HPLC as the cyclocondensation product of 1,2-benzenedithiol. The highest ITC metabolization (53.6 ± 15.7% over the total ITC ingested) was observed during the first 4 h after ingestion of raw product. However, the highest ITC metabolization after consumption of microwaved samples was delayed to 4–10 h, with 23.2 ± 27.6%. The high ITC metabolization during the first 4 h was most likely due to absorption in the small intestine, while the second peak (4–8 h) could be presumably attributed to an ITC absorption in the colon. The total ITC metabolization after raw kalian-hybrid consumption (79.1 ± 18.8%) was approximately 2-fold higher than that from microwaved broccoli (41.3 ± 8.8%), which was statistically significant (P, t test = 0.005). The ITC absorption of the kailan-hybrid was 2 times higher for raw and 3–9 times higher for cooked samples than the values previously reported in the bibliography with conventional broccoli varieties. Compared to other brassicas, kailan-hybrid can be presented as a vegetable with both, a high concentration and a great ITC metabolization.

Food Control, 2012

Water disinfection is a vital control-point to minimize transmission of diverse pathogens from wa... more Water disinfection is a vital control-point to minimize transmission of diverse pathogens from water sources or produce within and among lots at harvest, during initial postharvest handling, and within subsequent postharvest re-packing and processing. The use of ClO 2 as an alternative to NaClO for water disinfection is being adopted by the fresh tomato postharvest handling industry. Lack of data to define performance for this specific water sanitizer under commercial conditions is a barrier to setting meaningful standards and audit criteria for water sanitation and associated food safety goals. The current work aims to establish a correlative capacity of the Oxidation Reduction Potential (ORP) to ClO 2 dose, under different conditions of water turbidity and temperature, and their potential to reflect the efficacy in inactivation of Salmonella enterica in tomato process wash water during primary packing. ORP was monitored at delivered doses of 1, 3 and 5 mg/L ClO 2 , 10, 25 and 40 C water temperature, and varying turbidity (0, 40 and 160 NTU). As main results, inverse correlations between water turbidity, temperature and ORP were observed. An increase in turbidity significantly reduced the final ORP and increased the contact time required for a 5-log inactivation of S. enterica at any assayed temperature. An increase in temperature and ClO 2 concentration reduced the contact time and achieved a 6-log reduction of S. enterica within a 2 min of contact time. Additionally, differences in the required contact time were determined for inactivation of seven different S. enterica serovars. ClO 2 was effective in achieving a 6-log reduction, or greater, of S. enterica under a range of water quality and temperature. However, water composition strongly affects the dynamic ORP status which can limit total inactivation of S. enterica. Data acquired demonstrated the impacts of water quality and temperature to maintain an effective ORP toward inactivation of S. enterica. The outcomes of these studies will likely be useful in reassessing the current definition of adequate water quality and safety standards where ClO 2 is used.

European Food Research and Technology, 2001

Shogun' broccoli florets were film-wrapped and stored for 7 days at 1°C to simulate a maximum per... more Shogun' broccoli florets were film-wrapped and stored for 7 days at 1°C to simulate a maximum period of commercial shipment. After cold storage, florets were kept for 2.5 days at 20°C to simulate a retail sale period. For wrapping, polyvinyl chloride (PVC) 9 µm thickness and low-density polyethylene (LDPE) 11, 15, and 20 µm thickness were used. Soluble solids content, pH, titratable acidity, weight loss, physiological disorders, visual quality, and gas composition within packages were monitored. Gas composition (about 18% O 2 and 1% CO 2 during cold storage and about 16% O 2 and 2-3% CO 2 during shelf life), overall quality, and yellowing and browning of the florets were at similar levels among the films studied. However, weight loss was about sixty times lower for all LDPE films than for PVC film. After shelf life the best results were obtained by using 15 µm LDPE. This polymeric film could be a good alternative to PVC for wrapping broccoli for commercial shipment purposes, particularly to those countries where use of PVC has been forbidden.

European Food Research and Technology, 2000

For two consecutive seasons, 40 Spanish pomegranate cultivars (cvs) were analysed and their indiv... more For two consecutive seasons, 40 Spanish pomegranate cultivars (cvs) were analysed and their individual organic acids and sugars compositions were examined. Intervarietal differences in acidity content reported by different authors were confirmed. According to organoleptic characteristics and chemical compositions three groups of varieties were established: sweet (SWV), soursweet (SSWV) and sour (SV). On average, for two seasons, total organic acids on a dry basis ranged between 0.317 g/100 g (SWV) and 2.725 g/100 g (SV). Citric, malic, oxalic, acetic (first reported here), fumaric, tartaric and lactic acids were detected, although lactic and fumaric were not quantifiable. On average, for both seasons, citric acid was predominant with a range of 0.142±2.317 g/100 g (average content for all CVS, 0.282 g/100 g). Malic acid was the second most abundant, with a range of 0.135±0.176 g/100 g (average of 0.139 g/100 g). Total sugars ranged between 11.43 g/100 g and 13.5 g/100 g. Glucose, fructose, sucrose and maltose were detected, although maltose (first reported here) was not quantifiable. Fructose ranged between 5.96 g/100 g and 7.04 g/100 g, with an average of 6.58 g/100 g, quite similar to that of glucose (6.14 g/100 g). Sour cv showed the lowest fructose and glucose contents. The average sucrose content was 0.01 g/100 g. Other differences among the groups of cvs were detected. Low total sugars and high acids were found in SV. The SSWV group had higher sugars than the SV. However, no difference in total sugars between SSWV and SWV was found. A lower acids content than SV but higher than SWV was found in the SSWV group. No other studies have been published so far on the individual organic acids and sugars of pomegranate fruit.

European Food Research and Technology, 1999

For five new clones of pomegranate, cultivated under homogeneous conditions, changes in juice ant... more For five new clones of pomegranate, cultivated under homogeneous conditions, changes in juice anthocyanin contents during ripening were studied. Six anthocyanin pigments were found to be responsible for the red color of pomegranate juice. These were quantitatively and qualitatively analyzed by high-performance liquid chromatography and identified as delphinidin 3glucoside and 3,5-diglucoside, cyanidin 3-glucoside and 3,5-diglucoside and pelargonidin 3-glucoside and 3,5-diglucoside. Generally, there was an increase in juice pigmentation during fruit ripening. In the early fruit-ripening stages, delphinidin 3,5-diglucoside was the main pigment, followed by cyanidin 3,5-diglucoside, while in the later stages, the monoglucoside derivatives cyanidin 3-glucoside and delphinidin 3-glucoside increased considerably. The pelargonidin derivatives were always present in small amounts.

European Food Research and Technology, 2002

Fennel (Foeniculum dulce D. C. f. vulgare Miller) 'Orion' cv was stored up to 11 days at 0°C or 5... more Fennel (Foeniculum dulce D. C. f. vulgare Miller) 'Orion' cv was stored up to 11 days at 0°C or 5°C and 90-95% RH under controlled atmosphere (CA) of 5% O 2 +0% CO 2 and 5% O 2 +5% CO 2 (N 2 as the balance gas). In 'Clio' cv, CA of 5% O 2 +5% CO 2 and 5% O 2 +20% CO 2 for 14 days at 0°C and 90-95% RH were applied. As control, cold storage in air for both cv was used. A shelf life of 3-4 days at 15°C and 60-70% RH in air was applied. A low to moderate non-climacteric respiratory activity in both fennel cv was found. When temperature decreased from 5 to 0°C as well as when CA was applied a decrease on respiratory activity was shown. Respiration rates in 'Orion' were always higher than in 'Clio' cv. Heat production rates under different storage conditions were calculated. No fungal attacks developed in any treatment at any moment. Both fennels cv were insensitive to low O 2 and high CO 2 . No differences in visual appearance, aroma, flavour and texture after storage and shelf life on 'Orion' cv under all stated conditions were found. After shelf life in bulbs stored at 0°C browning of the butt end cut and of the external leaves were lower in 'Clio' than in 'Orion' cv and under both CA these disorders were inhibited. After shelf life in bulbs stored at 5°C only 'Orion' cv under 5% O 2 +5% CO 2 was marketable. Quality attributes changes under CA storage, respiratory activity and heat production rates of fennel are firstly reported here.

Palabras clave: Spinacea oleracea, cultivo sin suelo, calidad sensorial y microbiana, seguridad a... more Palabras clave: Spinacea oleracea, cultivo sin suelo, calidad sensorial y microbiana, seguridad alimentaria, cuarta gama. Resumen Se ha estudiado, por primera vez hasta donde conocemos, la evolución de la calidad organoléptica y microbiológica de cuatro variedades comerciales de espinaca "baby" (Dolphin, Eagle, Koala y 51-71) cultivadas en bandejas flotantes, tras su procesado mínimo en fresco y envasado en atmósfera modificada hasta 21 días a 5ºC. La actividad respiratoria de todas las variedades osciló entre 200 y 250 mg CO 2 / kg.h. En todos los casos, la atmósfera de equilibrio en el interior de los envases de polipropileno, termosellados con polipropileno orientado de 35 µm, se alcanzó tras 10 días con 7-9 kPaO 2 y 12-15 kPaCO 2 . Tras 21 días de conservación el mejor aspecto visual con buena calidad global lo obtuvo la variedad 51-71, seguida de la Dolphin. El recuento microbiano inicial fue bajo (3 a 4 unidades logarítmicas por g), lo que benefició la seguridad alimentaria, y permaneció siempre inferior a los límites legales, sin diferencias entre las cuatro variedades. La vida comercial de todas ellas fue de 21 días.

International Journal of Food Science & Technology, 2010

The differences in polyphenol oxidase, peroxidase, pectin methylesterase and polygalacturonase ac... more The differences in polyphenol oxidase, peroxidase, pectin methylesterase and polygalacturonase activities as well as the main physical and chemical attributes of nine different slice portions (from the inner to the outer end and from the blossom to the stem end) of two groups of melon (Cucumis melo var. cantalupensis 'Galia' cv. and inodorus 'Piel de sapo' cv.) at commercial maturity were studied. Moving from the inner to the outer end of the pulp, physico-chemical properties, such as pH, total soluble solids and phenolics increased whereas titratable acidity, firmness and Chroma decreased in both types, reflecting different degrees of maturity within the same fruit. As for physico-chemical attributes, the enzymatic activities responsible for browning and softening phenomena showed an increasing trend moving from the inner to the outer end of mesocarp in both cv., except for polygalacturonase in cantalupensis type.

The use of UV-C radiation treatments to inhibit the microbial growth and extend the shelf-life of... more The use of UV-C radiation treatments to inhibit the microbial growth and extend the shelf-life of minimally processed 'Red Oak Leaf' lettuce was investigated. Initially, UV-C resistance of 20 bacterial strains from different genera often associated with fresh produce (Enterobacter, Erwinia, Escherichia, Leuconostoc, Pantoea, Pseudomonas, Rahnela, Salmonella, Serratia and Yersinia) were tested in vitro. Most of the bacterial strains were inhibited with the minimum dose (30 J m À2 ). Erwinia carotovora, Leuconostoc carnosum, Salmonella typhimurium, and Yersinia aldovae were the most resistant strains requiring a UV-C dose of 85 J m À2 to completely inhibit growth. An in vivo study consisted of treating minimally processed 'Red Oak Leaf' lettuce (Lactuca sativa) with UV-C at three radiation doses (1.18, 2.37 and 7.11 kJ m À2 ) on each side of the leaves and storing the product under passive MAP conditions at 5 1C for up to 10 days. The gas composition inside packages varied significantly among the treatments, with CO 2 concentrations positively and O 2 concentrations negatively correlating with the radiation dose. All the radiation doses were effective in reducing the natural microflora of the product, although the highest doses showed the greatest microbial inhibitions. Taking into account the microbial limit set by Spanish legislation [Boletı´n Oficial del Estado (BOE), 2001. Normas de higiene para la elaboracio´n, distribucio´n y comercio de comidas preparadas, Madrid, Spain, Real Decreto 3484/2000, pp. 1435-1441, all UV-C treatments extended the shelf-life of the product. However, the 7.11 kJ m À2 dose induced tissue softening and browning after 7 days of storage at 5 1C. Therefore, the use of two sided UV-C radiation, at the proper dose, is effective in reducing the natural microflora and extending the shelf-life of minimally processed 'Red Oak Leaf' lettuce. r