Victor Escalona - Academia.edu (original) (raw)

Papers by Victor Escalona

Postharvest Biology and Technology, 2014

In recent years, the minimally processed food industry has increased due to a consumer trend towa... more In recent years, the minimally processed food industry has increased due to a consumer trend toward healthier eating. Among these products, watercress represents an interesting alternative due to its high content of functional compounds. The aim of this study was to investigate the effect of non-conventional modified atmosphere packaging (nitrogen (89.7% N 2 , 10.3% O 2), argon (89.9% Ar, 10.1% O 2), helium (90.1% He, 9.9% O 2), nitric dioxide (89.3% N 2 O, 10.7% O 2) and air (0.03% CO 2 , 21% O 2)) on fresh-cut watercress leaves preserved for 13 days at 5 • C. The respiratory rate was reduced by the non-conventional atmosphere up to 3 days of storage, and no significant effects were observed on C 2 H 4 production. In addition, mesophilic microbial growth was reduced up to 3 days of storage, and no effect was observed on psychrotrophic and Enterobactericeae counts. He and N 2 O atmospheres increased the antioxidant activity of watercress at the end of the storage period. Nevertheless, there was no clear effect of non-conventional gases on the color parameters, polyphenol contents and sensory parameters of fresh-cut watercress.

International Conference Postharvest Unlimited Downunder 2004, 2005

Italian Journal of Agronomy

Changes in plant responses have been associated with different fractions of the visible spectrum ... more Changes in plant responses have been associated with different fractions of the visible spectrum and light intensity. Advances in light emitting diodes (LED) have enabled the study of the effect of narrow wavelengths on plant growth and antioxidant compound synthesis. LED technology also facilitates the incorporation of light sources in a controlled setting where light spectra and intensity can be regulated. The objective of this study was to compare the effect of two commercial light spectra (S1: standard white light with 32.8% blue, 42.5% green, 21.7% red and 2.4% far red;S2: AP67 spectrum, designed for horticultural growth, with 16.9% blue, 20.5% green, 49.7% red and 12.3% far red) at two light intensities [LI: low intensity (78 µmol·m-2s-1 of photons for S1 and 62 µmol·m-2s-1 for S2, and HI: high intensity (102 and 100 µmol·m-2s-1 for S1 and S2, respectively)] on growth and antioxidant compound contents in two leafy vegetables: endive (Cichorium endivia L.) and lettuce (Lactuca ...

European Journal of Horticultural Science, 2007

Fresh-cut butter lettuce inoculated with Listeria in nocua was stored under controlled atmosphere... more Fresh-cut butter lettuce inoculated with Listeria in nocua was stored under controlled atmospheres (CA) containing 5 kPa O2 and 0 kPa CO2, 5 kPa O2 and 15 kPa CO2, 75 kPa O2 and 0 kPa CO2, 75 kPa O2 and 15 kPa CO2, and 21 kPa O2 and 0 kPa CO2 (as control) for 10 days at 7 °C. The growth of L. innocua, aerobic mesophilic bacteria, lactic acid bacteria and yeasts was studied. Additionally, the respiration rates and visual appearance of the butter lettuce were monitored in all treatments. The browning was measured on the let tuce stems using L*, chroma and hue values. High CO2 conditions promoted the growth of I. innocua. No O2 effect was found on the growth of L. innocua. However, when high O2 and CO2 conditions were combined, a reduction in the aerobic mesophilic bacterial count was observed. A high O2 condition alone could reduce the mesophilic count to the same extent as low O2 lev els combined with high CO2 levels while avoiding anaerobic fermentation reactions. The studied CA con...

Acta horticulturae, 2010

... S. Geysen, BE Verlinden, VH Escalona, A. Conesa and BM Nicolaï Flanders Centre/Laboratory of ... more ... S. Geysen, BE Verlinden, VH Escalona, A. Conesa and BM Nicolaï Flanders Centre/Laboratory of Postharvest Technology Katholieke Universiteit Leuven Willem de ... This value lies in the range normally found for EaVm,O2 in vegetable produce (around 40 to 110 kJ·mol-1 ...

Postharvest Biology and …, 2009

The minimal processing industry for fruit and vegetables needs appropriate selection of raw mater... more The minimal processing industry for fruit and vegetables needs appropriate selection of raw materials and operation of improved sustainable strategies for reducing losses and providing high quality and safe commodities. The most important target for keeping overall quality of these commodities is a decrease in microbial spoilage flora as these cause both decay and safety problems. Every step in the production chain will influence microbial load and the implementation of an accurate disinfection program should be the main concern of commercial processing. The only step that reduces microbial load throughout the production chain is washing disinfection, and the keys are proper handling and optimizing existing techniques or a combination of them. Chlorine is a common efficient sanitation agent but there is the risk of undesirable by-products upon reaction with organic matter and this may lead to new regulatory restrictions in the future. Moreover, its efficacy is poor for some products. Consequently the minimal processing industry wants safer alternatives. Several antimicrobial washing solutions, O 3 , UV-C radiation, intense light pulses, super high O 2 , N 2 O and noble gases, alone or in combination, are presently considered promising treatments. However, change from use of conventional to innovative sanitizers requires knowledge of the benefits and restrictions as well as a practical outlook. This review addresses some recent results obtained with these eco-innovative sanitizers on fresh-cut plant commodities.

Food Science and Technology

Twenty-two colored-flesh potatoes and three commercial noncolored-flesh varieties-which were all ... more Twenty-two colored-flesh potatoes and three commercial noncolored-flesh varieties-which were all raw as they were microwaved (800 W, 8 min) and fried (180 °C, 5 min)-were characterized in terms of functional, sensory aspects and suitability for use. Twelve genetic samples were more suitable for frying (> 20% dry matter), four for boiling (~15-18% dry matter) and nine for preparing puree or roasting (~18 to 20% dry matter). The total polyphenol content (TPC) of the raw colored-flesh potatoes contained between 1.10 to 3.68 g of gallic acid equivalent kg-1 in fresh weight (FW), which was between two-and threefold higher than the measured values in noncolored-flesh varieties. The total antioxidant capacity (TAC) was between 1.00 to 4.71 g of Trolox equivalent kg-1 FW, which was also lower in noncolored-flesh potatoes. The cooking process (frying and microwave) did not affect the TPC in most of the genetic samples analyzed, but it reduced the TAC by 40-75% (fried) and 30-90% (microwaved). According to sensory evaluation results, the genetic samples R2, R19, R3 and R5 were suitable for frying, while R16, R21, R9, R15 and R22 were suitable for microwaving. Colored-flesh potatoes are an interesting alternative for consumers due to their greater phytochemical content.

HortScience

Freshly harvested bulbs of fennel (Foeniculum vulgare var. dulce) `Clio' were sliced at 5 °C,... more Freshly harvested bulbs of fennel (Foeniculum vulgare var. dulce) `Clio' were sliced at 5 °C, dipped in 100 mg·L–1 NaOCl solution, and packaged in passive modified atmosphere packaging (MAP) by using trays covered and thermal sealed with unperforated or perforated polypropylene film. According to common commercial needs a shelf life of 14 d at 0 and 5 °C was applied. The respiration rate of fresh-cut fennel was 1.3- to 1.7-fold higher at 5 °C than at 0 °C, and was 1.4- to 1.8-fold higher than that reported for whole bulbs. MAP did not prevent the declines in SSC and TA that occurred during storage, while pH did not change. Water loss was lower than 0.1% in all treatments, and no decay or physiological disorders developed during storage. The gas compositions of 16 to 18 kPa O2 plus 2 to 4 kPa CO2 generated within the perforated packages at 0 and 5 °C or 1.5 to 2 kPa O2 plus 18 to 20 kPa CO2 in unperforated packages at 5 °C did not inhibit browning on the cut surface or other sens...

Postharvest Biology and Technology

The effect of a humidified flow of ozone-enriched air applied cyclically (4 ± 0.5 L L −1 of O 3 f... more The effect of a humidified flow of ozone-enriched air applied cyclically (4 ± 0.5 L L −1 of O 3 for 30 min every 3 h) on metabolic behaviour and sensorial and microbial quality of whole and fresh-cut 'Thomas' tomatoes stored up to 15 days at 5 • C was examined. The application of O 3 initially stimulated the respiration rate in a way similar to a stress, although after 2 days, the metabolic activity decreased to a rate lower than that of control (air flow). In O 3-treated whole and sliced tomatoes a higher sugar (fructose and glucose) and organic acid (ascorbic and fumaric) content was found. The kind of cut (whole or slices) did not affect the sensitivity of tomato to O 3. In whole tomatoes, O 3 maintained the tissue firmer than in control fruit while no influence was found on slices. The O 3 treated fruit retained a good appearance and overall quality in slices but experienced a reduced aroma. Also, O 3 substantially reduced microbial counts, being more noticeable on bacteria (1.1-1.2 log 10 units) than on fungi (0.5 log 10 units). This effect was higher when the storage time was longer and when a higher O 3 level (7 L L −1) was used. O 3 did not cause any damage or off-flavour in slices or whole tomatoes. In conclusion, the assayed O 3 treatment can be useful for maintaining quality and reducing microbial populations in whole and sliced tomato.

Postharvest Biology and Technology, 2017

CyTA - Journal of Food, 2016

Escalona (2017) Compositional changes on colored and light-yellow-fleshed potatoes subjected to t... more Escalona (2017) Compositional changes on colored and light-yellow-fleshed potatoes subjected to two cooking processes, CyTA

Lebensmittel Wissenschaft Und Technologie, Apr 1, 2007

To improve the keeping quality of the kohlrabi stems and avoiding wilting of the leaves, modified... more To improve the keeping quality of the kohlrabi stems and avoiding wilting of the leaves, modified atmosphere packaging (MAP) with oriented polypropylene and amide-polyethylene copolymer bags was applied. Avoiding wilting of the kohlrabi leaves is crucial because European consumers consider the freshness of kohlrabi leaves as a key quality parameter. Whole kohlrabies were stored within, abovementioned sealed bags, for 14 days at 0 1C and 95% RH, followed by 3 days at 10 1C. In the MA packages gas compositions of about 5 kPa O 2 and 10-15 kPa CO 2 were generated. The respiratory activity, C 2 H 4 production, firmness (of stems and leaves), sugars, organic acids contents, as well as chemical and sensory quality attributes were monitored. The respiratory rate of the kohlrabi stems in air at 0 1C was 10-11 mg CO 2 /kg/h with a C 2 H 4 production lower than 0.05 ml/kg/h (traces). However, when the temperature was increased at 10 1C the respiration rate raised 3.5 folds. Acidity, pH, soluble solids, sugars and organic acids content and firmness did not show significant changes at the end of both cold storage and retail sale periods. MAP was very effective improving keeping quality of the stems and retarding wilting of the leaves. During the retail sale period at 10 1C, the bags must to be perforated to avoid anaerobic conditions.

Revista Iberoamericana De Tecnologia Postcosecha, 2013

Proyecto académico sin fines de lucro, desarrollado bajo la iniciativa de acceso abierto Ensalada... more Proyecto académico sin fines de lucro, desarrollado bajo la iniciativa de acceso abierto Ensaladas de frutas mínimamente procesadas… González Marta y Cols. (2013)

Revista Iberoamericana De Tecnologia Postcosecha, 2012

The controlled atmosphere technique is used to understand the effect of gas composition (O 2 and ... more The controlled atmosphere technique is used to understand the effect of gas composition (O 2 and CO 2) on the quality of minimally processed fresh fruit (MPF). The aim of this study was to evaluate the effect of low concentrations of oxygen and carbon dioxide moderate (% CO 2 +% O 2) (21 +0, 0 +5, 5 +0, 5 +5) on the content of aroma and carotenoids (mainly β-carotene and cryptoxanthin) of wedges of 'Royal Glory' peaches treated with an antibrowning solution (0.5% ascorbic acid + 0.5% citric acid + 0.5% CaCl 2) and stored 9 d at 5 ° C. The aroma volatile compounds were extracted from the headspace of MPF peaches by SPME and analyzed by GC-MS, while the carotenoid content was analyzed by HPLC. The aroma profile of whole and MPF peach consisted hexanal, Establecimiento de la composición de la… Maulén, Andrea y cols. (2012)