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The present work investigates how ultrasound pretreatment modulates the effects of osmotic dehydration (OD) on the water state and microstructure of kiwifruit. Kiwifruit slices (10 mm thick) were subjected to ultrasonic waves in a water bath at a frequency of 35 kHz for 10, 20 and 30 min. OD process was then carried out by immersing the samples in 61.5% sucrose solution equilibrated at 25 °C for a contact period of 0, 10, 20, 30, 60 and 120 min. The partition of water into the cellular tissue structures (vacuole, cytoplasm, extracellular spaces and cell wall) was investigated by Time Domain Nuclear Magnetic Resonance (TD-NMR). In parallel, the microstructure of kiwifruits slices was examined using a Scanning Electron Microscope. The results showed that US pretreatment performed for more than 10 min had a positive effect on the mass exchange caused by osmotic dehydration. A creation of microchannels and an increase of the average cross-section area of cells were observed when the samples were pretreated with US before OD. TD-NMR showed a slight redistribution of water through the substructures of the cells, as a function of the length of the US pretreatment applied.

Whole strawberries were vacuum infused with cryoprotectants to improve their freezing tolerance. The strawberries were infused with 12 g/100 g trehalose solution; 0.2 g/100 g cold-acclimated wheatgrass solution (AWWE) containing antifreeze protein (AFP) or combination of 12 g/100 g trehalose with 0.2 g/100 g AWWE under vacuum for 14 mm. The fruits were frozen in liquid nitrogen and thawed at room temperature before being evaluated for cell viability, drip loss and preservation of texture. The results showed that the combined effects of both cryoprotectants significantly improved the freezing tolerance of the treated strawberries. The cryoprotection effect was influenced by the heterogeneity of the tissues in the fruits. (C) 2011 Elsevier Ltd. All rights reserved. (Less)

The influence of several process steps on the rheological, textural and calorimetric characteristics of dark chocolate was evaluated. Samples were obtained at each phase of the manufacturing process: mixing, pre-refining, refining, conching and tempering. Rheological fundamental and empirical properties and thermal characteristics were evaluated on samples. Samples showed marked shear thinning behaviour with yield stress strictly related with the different process steps. Fundamental measurements results were well fitted by the power-law model. From the mixing to the refining samples underwent a drastic significantly (p < 0.05) increase of all considered fundamental (yield stress, apparent viscosity, G′, G″ and K index), empirical (firmness, consistency, cohesiveness, viscosity index) and thermal parameters (T onset, T end, ΔH). This could be attributed to the reduction of samples particle size that involve an increase of the contact point between them. Subsequently, the addition of fat and lecithin in conching and tempering phase, covering the sugar and cocoa particles, reduced interactions and caused a significantly (p < 0.05) decrease in all rheological, textural and thermal parameters.

The aim of this work was to evaluate the influence of the ripening stage on fresh-cut kiwifruit tissues in terms of quality and tissue metabolism, during accelerated storage (AS) in controlled conditions. For this purpose three different ripening stages were selected, corresponding to about 11, 13 and 15 °Brix. For each ripening stage the fruits were peeled and cut into 1 cm thick slices and stored in climatic chambers at 10 °C, 90% RH, for 3 days. During storage, quality indices as soluble solid contents, titrable acidity, colour and texture were monitored. Metabolic assessment was carried out evaluating the endogenous metabolic heat using isothermal calorimetry, and monitoring O2 consumption and CO2 production simultaneously. Differences were found in the evolution of the quality indexes during storage; in particular kiwifruit at the lowest ripening stage showed the slowest quality degradation, both in terms of softening and visual quality modifications. Metabolic heat production results were different at the different ripening levels investigated, evidencing a strict connection between the physiological state of the tissue and the entity of its wounding response.

La réaction de Maillard représente la principale source de modifications chimiques, physiques et sensorielles des produits alimentaires au cours des traitements thermiques et de longues périodes de stockage. Celle-ci est le phénomène le plus important entre ceux qui prennent le nom de “brunissement non enzymatique” (NEB). En particulier, la formation des arômes et le développement des composants de couleur brune caractérisent les phases secondaires de la réaction, qui commence avec une condensation entre un groupe aminé (présent généralement soit dans les aminoacides soit dans des autres composants des aliments) et un groupe aldéhyde d’un sucre réducteur ou d’autres composants carbonylés, avec la formation d’eau. A partir de ces exemples des phénomènes de brunissement de produits alimentaires. Les modifications chromatiques peuvent varier de la crème blanche du lait pasteurisé, au jaune plus ou moins intense de la pâte jusqu’au brun des biscuits ou des produits cuits au four. L’opinion des consommateurs sur l'impact que les modifications de la couleur peuvent avoir, doit tenir compte du rapport risque/bénéfice, c’est-à-dire des autres phénomènes se produisant au cours de la réaction de Maillard, comme la formation possible de composés toxiques (acrylamide, HMF, furanes, etc.), la perte nutritionnelle ou des indices de dégradations thermique (perte de lysine, formation de furosine) mais aussi la formation de composés de la réaction de Maillard ayant des effets positifs (anti oxydant, antimicrobien) qui peuvent favoriser la stabilité microbienne et oxydative des produits alimentaires considérés

This study reviews the toughening and plasticization effects of water on coffee beans in terms of texture modifications and water status and mobility, investigated by the joint use of sorption isotherms, DSC, LF-NMR and integrates the results of the dielectric properties assessment currently ongoing on green and roasted coffee beans. This multi-analytical approach is aimed to a better understand the role of water status in the determination of the toughening and plasticization effect.

A screening of life cycle assessment (LCA) methodology to the evaluation of the damage arising from the life cycle of Polystyrene (PS), Polyethylene Terephtalate (PET) and Polylactic acid (PLA) boxes used for food packaging application has been carried out. For every line of product the environmental impact of the expanded version and the rigid version was takes into consideration. Purpose of the experimental work was to individualize and analyze the principal tied up environmental impacts to the life cycle for packing produced commercially. The study, after the phase of damage evaluation, allowed us to advance a possible proposals of improvement, with the purpose to minimize the total damage and to guarantee a level how much great possible of the environmental sustainability of the examined products. The production of the boxes in expanded material involves the use a less percentage of row material in comparison to the rigid boxes. The production process is articulated as following: 1) Melting of virgin granules; 2) Extrusion of the melted material; 3) Production and cooling of the obtained leaf; 4) Stamping of the leaf. In the case of the expanded material, in the first phase an expanding liquid is added, generally butane. The leaf of expanded polymer needs a period of rest, that allows the expanding gas to go out of the leaf. Only in some cases, the box is laminated with a multilayer film, type PSEVOH- PE.

The rheology study of complex systems made up from different solid particles dispersed in a continuous fluid, such as nut creams, is important because it is related to the efficiency of the main process steps and to the quality, stability and sensorial characteristics of final products. In particular formulation and the used ingredients become key parameters that can affect strongly their rheological properties. The effects of different types (palm oil and hydrogenated fats - HF) and amounts of fats, on the rheological and textural properties of laboratory made nut creams were evaluated. The creams were produced in roller ball mill pilot plant, and colour (hue angle, Chroma), rheological (steady and dynamic measurements) and textural (back extrusion test) characteristics were evaluated. The experimental nut creams were compared with two commercial ones. The highest amounts of HFs (50%) led to an increase of consistency, viscosity and elasticity of creams compared to ones without or with low level of HFs (25%), probably due to the presence of strongly fat networks that implies more aggregated structure. In particular, among the experimental creams, sample having in formulation 75% of palm oil and 25% of HFs showed fundamental (G’’ and K index) and textural properties similar to the commercial cream leader of market. Moreover it was found that the increase of HFs quantity in creams involves a reduction in hue angle and chroma values. Finally, both fundamental and empirical considered parameters resulted to be equally useful and sensitive in discriminate rheological properties of the different cream samples.

The effects of osmotic dehydration (OD) on kiwifruit outer pericarp tissue as affected by treatment extent (0–300 min) and raw kiwifruit ripening stage (9 and 14 °Bx) were investigated. Differential scanning calorimetry (DSC) measurements show decomposition of cell wall components (pectins, cellulose and hemi-celluloses). Changes in decomposition parameters (peak temperature lowered and enthalpy increased) were observed related to kiwifruit ripening degree and OD extent increased. Cell wall pectin network disassembly led to the formation of compounds with lower degradation temperature. Raw unripe fruits showed higher firmness values and lower compressibility compared to ripe and OD treated fruits. Isothermal calorimetry revealed metabolic heat production of unripe fruits decreasing linearly with the OD extent. Ripe fruit heat production sharply decreased during the first treatment hour, probably as a consequence of membrane integrity loss. Industrial relevance OD leads to moisture removal and solute uptake in vegetable tissue, providing minimally processed commodities or ingredients for bakery or ice-cream industry. The industrial relevance is the energy-efficiency, since the process does not require water-phase change. OD provokes still unknown collateral alterations on tissue structure and metabolism. The present work applies a new calorimetric approach to evaluate both structure and metabolism changes on kiwifruit as reliant on process extent and raw fruit ripening stage.

Whole strawberries were impregnated using vacuum infusion with different cryoprotective solutions to improve their freezing tolerance. The cryoprotective solutions used were: 12% (w/w) trehalose solution; 0.2 % (w/w) cold acclimated wheatgrass solution (AWWE) containing antifreeze protein (AFP) and combination of 12% (w/w) trehalose with 0.2 % (w/w) AWWE. The strawberries (70±5 g) were immersed in the coresponding solution under vacuum for 14 min. After the infusion the fruits were removed from the solution, blotted, dipped in liquid nitrogen for 25 s to freeze and then thawed for 2 h at room temperature. The quality of the strawberries after one freezing/thawing cycle was evaluated trough determination of the cell viability, drip loss, colour loss and preservation of texture firmness. The cryoprotective effect of the solutions depended on the heterogeneity of the tissues in the fruit. The results proved that there was evident reduction in the drip loss of the strawberries by using the combined effects of both cryoprotectants. Furthermore this combination significantly improved the overall freezing tolerance of the treated fruits, by obtaining cell viability in most of the tissues; reducing the colour loss to non-significant level when compared to the fresh strawberries and preserving the flesh firmness.

This paper presents the results of the comparison of different analytical techniques (Differential Scanning Calorimetry - DSC, Low Field Nuclear Magnetic Resonance - LF-NMR, Light Microscopy - LM and Transmission Electron Microscopy – TEM) in order to evaluate the mass transfer, water status and cellular compartment modifications of the kiwifruit outer pericarp tissue during osmotic dehydration treatment (OD). Two kiwifruit species, A. deliciosa and A. chinensis were submitted to OD. OD was performed in a 61.5 % w/v sucrose solution at three different temperatures (25, 35 and 45 °C), with treatment time from 0 to 300 min. Peleg’s model highlighted that the main response differences between the two kiwifruit species occurred during the initial phase of the osmotic treatment. DSC parameters appeared to be sensitive to water and solid exchange between fruits and osmotic solution. LF-NMR proton T2 revealed the consequences of the water-solid exchange on the cell compartments, namely vacuole, cytoplasm plus extracellular space and cell wall. During OD, the reduction of the vacuole proton pool, detected by LF-NMR, suggested a shrinkage of such compartment, confirmed by LM. Cell walls of outer pericarp showed considerable changes in size, structure and stain uptake during OD observed at TEM. The proposed multianalytical approaches should enable better design of combined processing technologies permitting the evaluation of their effects on tissue response. U ovom radu su prikazani rezultati poređenja različitih analitičkih tehnika (Diferencijalna skeniranja Kalorimetrija – DSC, Niska Polje nuklearna magnetna rezonanca - LF-NMR, svetlost mikroskopije - LM i Prenos elektronsku mikroskopiju - TEM), u cilju određivanja prenosa mase, statusa vode i modifikacije ćelija tkiva perikarpa kivija tokom osmotske dehidratacije tretmana (OD). Dve sorte kivija su bile izložene osmotskom tretmanu, A. deliciosa i A. chinensis. Osmotsko sušenje obavljeno je u 61,5% rastvoru saharoze na tri različite temperature (25, 35 i 45°C), sa vremenom trajanja sušenja od 0 do 300 minuta. Pelegovim modelom naglašene su glavne razlike između dve sorte kivija koje se događaju tokom početne faze osmotskog tretmana. DSC parametri osetljivi su na izmenu vode i čvrste materije između voća i osmotskog rastvora. LF-NMR-om otkrivene su posledice razmene vode i čvrste materije na ćeliju, odnosno vakuole, citoplazmu sa vanćelijskim prostorom i ćelijski zid. Tokom OD, smanjenje vakuole protona bazena, otkrivena je LF-NMR, predložio skupljanja takvog odeljka, potvrđeno LM. Ćelijske zidove spoljne perikarpa su pokazali značajne promene u veličini, strukturi i mrlja uzimanja u toku OD posmatrano na sistem. Predloženi multianalitical pristupi treba da omogući bolji dizajn u kombinaciji obrade tehnologija dozvoljava procenu njihovog uticaja na tkivo odgovor. Fil: Dalla Rosa, Marco. Università di Bologna; Italia Fil: Tylewicz, Urszula. Università di Bologna; Italia Fil: Panarese, Valentina. Università di Bologna; Italia Fil: Laghi, Luca. Università di Bologna; Italia Fil: Pisi, Annamaria. Università di Bologna; Italia Fil: Santagapita, Patricio Roman. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rocculi, Pietro. Università di Bologna; Italia

Vacuum Impregnation in food industry is an interesting process particularly in semy-dry fruit processing. At the beginning of the process the pressure is reduced and the internal gas in the product pores is expanded and partially flows out, after that, when atmospheric pressure is restored and residual gas is compressed, the external liquid flows into the pores. Although vacuum impregnation process has been widely studied, the metabolic consequences of the vacuum impregnation with different solutions on fruit tissue are still not well understood. The aim of this work was to study the metabolic consequences of vacuum impregnation on apple tissue. In particular, the respiration rate and the possibility of vesicular transport within the cells were explored.

In this research, recent results of isothermal calorimetry studies focused on differently processed and stored fresh-cut fruit are presented. Particularly the calorimetric approach has been applied in order to better understand the physiological response of fresh-cut kiwifruit, apple and cantaloupe tissues as a consequence of: - osmo-dehyration in sucrose solution for different treatment times, on the metabolic heat production of fresh-cut kiwifruit; - modified atmosphere exposure, on the metabolic heat production of fresh-cut apples, with an innovative instrument set-up; - storage in different syrup formulations, on the microbial growth heat production on fresh-cut cantaloupe. Obtained results are very promising, evidencing important aspects such as: - a progressive metabolic heat reduction of kiwifruit tissue with the proceeding of the osmotic treatment; - the inhibitory effect of specific gas mixtures with traditional and/or innovative packaging gases in terms of metabolic heat production of apple tissue; - the potentiality of this technique for the optimization of syrup formulation, in order to increase the microbiological stability of fresh-cut cantaloupe.

Osmotic dehydration is a partial dewatering process by immersion of cellular tissue in a hypertonic solution, which is accompanied by solutes counter-diffusion into the tissue. Low field-nuclear magnetic resonance (LF-NMR) seems to be a promising technique to follow the distribution of water/solutes through the cellular tissue during treatment. The objective of the present study was to evaluate the cellular compartment modifications of kiwifruit (Actinidia deliciosa) outer pericarp tissue caused by osmotic treatment in a 61.5% sucrose solution through the quantification of transversal relaxation time (T2) and water self diffusion coefficient (Dw) obtained by LF-NMR means. Proton T2 of the samples was measured using CPMG sequence. Three T2 were obtained of around 30, 200 and 1000 ms, which could be ascribed to the protons located in the cell walls, in the cytoplasm/ extracellular space, and in vacuoles, respectively and could be directly compared to those described in the literature for several fruits and vegetables. Vacuoles T2 represented around 66% of total kiwifruit protons. The leakage of water leading to vacuoles shrinkage seemed to cause a concentration of solutes, retained by the tonoplast, making the vacuoles T2 decrease at each treatment time. Dw were measured by means of the pulsed field spin-echo (PFSE) sequence. As expected, the kiwifruit Dw values measured in the raw kiwifruit were lower than free water one, as the structures and solutes of raw kiwifruit reduce water mobility, and decrease even more during osmotic treatment, due to the water loss and sugar gain. The coefficient measured by means of PFSE represented an average value of the whole kiwifruit tissue protons. In order to obtain Dw values specific for each cellular compartment, a two compartment fitting was also used. The Dw correspondent to vacuoles was much higher than the average one Dw.

The effect of different type of cooking methods on the chemical, physical and nutritional characteristics of broccoli (Brassica oleracea L.) was studied. Broccoli samples were cooked with steam, with a steam/microwave combined method, and with microwave cooking by using an accessory that generates steam. The treatment times were 15, 9 and 15 min, respectively. The fresh and cooked samples were evaluated for weight loss, water content, color, texture, free and total polyphenols content, and antioxidant capacity. Moreover, the dielectric properties of the samples were determined in order to analyze the viability of determining some nutritional and quality aspects of broccoli during the cooking operation. The results showed that the highest weight loss was observed in samples cooked with steam/microwave combined method (25 ± 1.5%). On the other hand, the polyphenols content increased with all the cooking methods analyzed. Dielectric properties changed significantly during the cooking treatments and showed good correlations with some of the chemical, physical and nutritional parameters studied.

The role of fruit in a healthy diet is growing because fruits are an important source of vitamins, antioxidants and basic ions such as potassium or calcium, which are fundamental in an equilibrated meal. Self life of fruit is short and requires conservation techniques to enhance its commercial life. In this sense, the online control of conservation treatments is essential to preserve the compounds with functionality. Dielectric spectroscopy is a good technique to control polar components such as water and also components with charge such as antioxidants or ions. The aim of this work is to analyze the chemical and structural changes in the osmotic treatment of kiwifruit by using dielectric spectroscopy. The osmotic treatment consisted on immerse the samples into 65% (w/w) sucrose aqueous solution at 30ºC during 60, 90, 120, 180, 250, 320, 400, 720, 1440, 2000 minutes. Some physical-chemical parameters were measured in fresh, treated and reposed (24h at 30ºC) samples. Dielectric spectra were measured in the frequency range from 500 MHz to 20 GHz by an Agilent 85070E Open-ended Coaxial Probe connected to an Agilent E8362B Vector Network Analyzer in the fresh, treated and reposed samples.

In tale lavoro è stata fornita una visione critica delle principali ricerche riguardanti lo studio degli effetti delle operazioni di preparazione e di conservazione sulle caratteristiche nutrizionali degli ortofrutticoli di IV gamma.

In the frame of the EU project Training Requirements and Careers for Knowledgebased Food Science and Technology in Europe (Track_Fast), a Support Action of FP7 KBBE (Project number 227220), a session on best and worst practices to attract students to the food science and technology studies has been carried out as an activity of the workpackage 4 on Motivation for Pursuit of a Career in FS&T. WP4 leading is performed by EFFoST. Information based on activities organized by the partner’s institutions or involving the partners, were presented.

This study dealt with the characterization and quality assessment of 3 kinds of potato-based pasta (gnocchi) made with steam-cooked, potato puree (water added to potato flakes), and reconstituted potatoes as main ingredients. The aim of the research was to evaluate the quality of the products in terms of physicochemical, textural, and sensory characteristics. Water content, water activity, color (L* and h°), and texture (texture profile analysis [TPA] and shearing test) were evaluated on both raw and cooked samples. In addition, on the recovered cooking water the loss of solid substances was determined and on the cooked gnocchi a sensory assessment was performed. Eight sensory attributes (yellowness, hardness, gumminess, adhesiveness, potato taste, sweet taste, flour taste, and sapidity) were investigated. Statistically significant differences among products were obtained, especially concerning textural properties. In fact, sample made with reconstituted potatoes and emulsifiers resulted the hardest (8.53 ± 1.22 N), the gummiest (2.90 ± 0.05 N), and the "chewiest" (2.90 ± 0.58 N) after cooking. Gnocchi made with potato puree or reconstituted potatoes significantly differed from the one produced with steam-cooked potatoes in terms of sensory properties (yellowness, hardness, flour taste, and sapidity). Pearson's correlation analysis between some textural instrumental and sensory parameters showed significant correlation coefficients (0.532 < r < 0.810). Score plot of principal component analysis (PCA) confirmed obtained results from physicochemical and sensory analyses, in terms of high discriminant capacity of colorimetric and textural characteristics.

Kiwi is an important fruit in the diet because contains vitamins, antioxidants and ions, fundamentals in an equilibrated meal. Self life of this fruit is short and requires conservation techniques to enhance it commercial life. In this sense, modern techniques to analyze how change the product (as SAFES) and how change through the treatment, allow as to develop a new product with the specific characteristics what are looking for. SAFES methodology (Systematic approach in food engineering systems) is a technique to describe the structure of food through any treatment which provides the physicochemical transitions, chemical and biochemical reactions and energy and mass transports. The aim of this work is to explain how change the structure of kiwi through the osmotic dehydration with 61,5% (w/v) sucrose solution at 45ºC, at short times from 0 to 300 minutes. Since the short times of dehydration applied did not allow the equilibration of the system and there were continuous changes of parameters, only one Matrix of changes was indentified. Considering the kiwifruit as a biological system compost of cells, pores and intercellular spaces, two types of tissue (vascular and parenchymatic) were individuated on the basis of cell characteristics that can influence the transport. Moreover the different phases as solid matrix and liquid phase were found in both tissues. One of the main ingredients of kiwifruit is water and its distribution was studied by SAFES application. The water sorption isotherm (Moraga et al., 2006) was used to characterize the adsorbed water in solid matrix, while the sharing out of the liquid water in vascular and parenchymatic tissues was performed by the external volume evaluation.

The relationship between food and health has an increasing impact on food innovation due to the popularity of the concept of functional food. Many food ingredients, such as herbs and spices, have been included in bread formulation to increase its diversity, nutrition or product appeal. In this study Zingiber officinale Roscoe, due to its affirmative action, was incorporated in bread formulation. The aim was to examine the possibilities of improving the quality of wheat flour based bread by using different amounts of ginger powder in order to obtain an antioxidant enriched bread with good physico-chemical and sensorial properties.

Nella produzione degli ortofrutticoli di IV gamma (OIV), le operazioni di preparazione sono responsabili dell’aumento dei fenomeni metabolici del tessuto vegetale (Mencarelli e Massantini, 1994). La previsione della shelf-life può essere attuata controllando gli agenti responsabili delle alterazioni qualitative (come la carica microbica e l’attività enzimatica) o monitorandone gli effetti (come le modificazioni del colore e/o la comparsa di sapori ed odori anomali). Per gli OIV tale approccio risulta molto complicato a causa della complessità intrinseca del prodotto, che continua a modificarsi a seguito della sua vitalità. In questa direzione la calorimetria in isoterma può essere utilizzata per ottenere un’indicazione diretta dell’attività metabolica dei tessuti vegetali, dovuta principalmente a fenomeni respiratori endogeni ed esogeni, aerobici ed anaerobici, legati al metabolismo da ferita ed allo sviluppo microbico. Un calorimetro misura la somma di tutto il calore prodotto dal campione, sia endogeno (metabolismo respiratorio), che esogeno (in caso di sviluppo microbico), permettendo di studiare un sistema biologico senza scendere nei dettagli. Un primo approccio calorimetrico per la comprensione e la minimizzazione degli eventi dovuti allo stress da ferita, è quello di stabilire la relazione tra il grado di lesione del tessuto vegetale e la sua attività metabolica, nonché quella dovuta allo sviluppo microbico (Wadsö et al., 2004). In passato sono stati effettuati numerosi studi riguardanti l’effetto di pre-trattamenti di immersione in soluzioni stabilizzanti (dipping) sulla qualità di OIV. La limitata conoscenza del loro effetto sul metabolismo del prodotto può essere estesa con l’ausilio della calorimetria in isoterma, anche in condizioni di stoccaggio refrigerato o invecchiamento accelerato (Rocculi et al., 2007). In aggiunta è possibile implementare studi metabolici fondamentali calo-respirometrici, sia in condizioni di aerobiosi che di anaerobiosi o di atmosfera controllata, attraverso la simultanea misura dell’energia metabolica con quella della velocità di consumo di O2 o di produzione di CO2, ottenendo informazioni molto utili per la scelta dell’atmosfera protettiva e della permeabilità dell’imballaggio ottimale (Gomez et al., 2005). Premesso questo, scopo del presente lavoro è quello di fornire una visione complessiva delle potenzialità della calorimetria in isoterma come tecnica per monitorare e predire l’evoluzione qualitativa di OIV

Osmotic dehydration consists of fruit immersion in hypertonic solution, generally from sugars, and it is one of the most interesting techniques for the shelf-life extension of fresh-cut fruit, as a partial removal of water from the tissues. Aim of this study was to investigate the effect of different times and temperatures of immersion in a specific sugar osmotic solution in the mass transfer phenomena and the main qualitative characteristics of two kiwifruit cultivars, one of them recnognised as "standard" kiwifruit (cv. Hayward) and the other better known as the new "yellow" kiwifruit.

L’1-Metilciclopropene (1-MCP) è un antagonista dell’azione dell’etilene recentemente inserito nella lista dei composti che si possono utilizzare per prolungare la shelf-life di prodotti di origine vegetale. Gli effetti dell’1-MCP sul rallentamento della maturazione sono stati dimostrati sia su frutto intero che sulla frutta tagliata ma in letteratura pochi sono i dati riferiti all’infl uenza dei trattamenti con 1-MCP sul contenuto nutrizionale di frutta fresh cut durante la conservazione. Lo scopo di questa ricerca è lo studio dell’effetto dell’utilizzo di miscele di gas innovative in combinazione con 1-MCP sul contenuto di acido ascorbico (AA) e deidroascorbico (DHA) in fette di kiwi (cv. Hayward) minimamente processate durante la conservazione refrigerata

Modified atmosphere packaging (MAP) is a widely used food storage technique that receives consumer perception as a natural and additive-free technique. The aim of this study was to compare some physico-chemical and technological properties of albumen of not-packed eggs (control) with that of eggs packed in high barrier plastic pouches, in air and in 100% CO2 MA. Fresh eggs and egg samples during 28 days of storage were analysed for albumen pH and dissolved CO2, Haugh unit (HU), texture of the coagulated albumen and crispness of meringues. Our research confirmed the beneficial effect of 100% CO2 MAP on egg freshness maintenance. In addition our findings showed that the exposition of shell egg to CO2 improved some technological performances of the albumen (e.g. meringue crispness), showing also high potentiality in order to modulate the hardness of coagulated albumen.

Un nuovo metodo elettroforetico, basato sull’elettroforesi capillare zonale (CZE), è stato sviluppato e confrontato con l’HPLC nella determinazione del contenuto di acido trans-10-idrossi-2-decenoico (10-HDA), in campioni di gelatina reale (GR) pura. Il metodo impiegava, come elettrolita di supporto, modeste quantità (c.a. 50 ml per 100 corse) di un tampone di tertaborato di sodio 50 mM. Un ampio intervallo di risposta lineare (0,006-0,808 mg-HDA/ml), una buona sensibilità (limiti di rilevabilità e di quantificazione: 0,002 e 0,004 mg/ml, rispettivamente), una soddisfacente ripetibilità strumentale sia rispetto al tempo di ritenzione dell’analita che dell’area del picco (RSD% inferiore a 1,0 e 2,0% per il tempo di ritenzione nella stessa giornata e in tre giorni consecutivi, rispettivamente) e un tempo di analisi ridotto (13 minuti per ciascuna corsa, incluse le fasi di lavaggio) erano le principali caratteristiche del metodo CZE. I risultati ottenuti mediante CZE ed HPLC erano significativamente correlati (p

Fresh-cut fruit and vegetables are minimally processed products that have to maintain their quality (appearance, texture, flavour and nutritive value) similar to that of the fresh product. The fundamental principle underlying the quality of these commodities is that they have metabolic active tissues and, as a consequence, show physiological response to preparation procedures as well as to the environment created in the package in which they are enclosed. In this product category, fresh-cut potatoes (Solanum tuberosum L.) could have a great importance from a commercial point of view, because of their high convenience, even if they are susceptible to a variety of physiological and microbiological phenomena during storage. Because of economic, labour and hygiene considerations, the potato processing industry has seen promises in offering potatoes as a freshcut product (pre-peeled, fresh-cut or sliced). Minimal processing for fresh-cut potato production includes raw material selection, washing, peeling and cutting, pre-treatments, drying, weighing and packaging. From a biological point of view, industrial treatments for the fresh-cut potato production can cause stress to the tuber and, therefore, knowledge of how the plant material will be affected in relation to time, environment and industrial manipulation is of fundamental importance for process optimization and quality assurance. The purpose of this review is to analyse the effects of the different minimal processing steps on the physiology and related quality of fresh-cut potatoes. To this aim, the manuscript has been divided into the following sections: production of fresh-cut potatoes; physiology and quality of fresh-cut potatoes (Respiration and metabolic consequences of minimal processing, Quality modifications, Colour and visual quality, Texture, Microbial spoilage, Flavour, Nutritional aspects); hurdle technology and fresh-cut potatoes (Sanitization, Pre-treatments, Modified atmosphere packaging, Refrigeration); future perspectives. Particular attention is given to the newest studies on processing innovation and innovative scientific approaches for a better understanding of fresa-cut products as biological systems. In this direction, the use of ozone sanitization, natural dipping pre-treatments and/or coatings (e.g. edible film enriched in ascorbic and citric acid), and modified atmosphere packaging at high O2 levels result the most promising and non-invasive techniques for the preservation of fresh-cut potatoes. As far as physiological studies of the product are concerned, fundamental metabolic research for process optimisation and quality assurance is needed. For this aim, isothermal calorimetry may provide a versatile tool to conduct fundamental metabolic studies of the effect of different processing steps on the quality and shelf-life of fresh-cut potatoes.

Il consumo di alimenti di origine vegetale è inversamente correlato al rischio associato all’insorgenza di molte patologie da stress ossidativo. Gli effetti benefi ci determinati dal consumo di vegetali sono imputati anche al loro alto contenuto in antiossidanti. I vegetali vengono consumati non solo come alimenti freschi, ma anche trasformati. L’attività antiossidante dei vegetali può essere ridotta dal processo di trasformazione, a causa di ossidazioni o degradazione termica degli antiossidanti, ma può essere anche incrementata da fenomeni di ossidazione parziale, idrolisi ed imbrunimento non enzimatico (NEB). La temperatura di processo può infl uenzare la AOA di un alimento secondo diversi meccanismi: (i) aumentando l’energia cinetica dei reagenti; (ii) infl uenzando la solubilità dell’ossigeno; (iv) aumentando l’accessibilità degli antiossidanti a seguito di danneggiamento dei tessuti; (v) infl uenzando la viscosità del sistema alimento; (vi) o la concentrazione degli antiossidanti. Quindi una corretta modulazione della temperatura può permettere l’ottimizzazione di un processo di trasformazione nell’ottica di massimizzare la AOA del prodotto fi nale. In questo articolo i risultati ottenuti da diverse ricerche condotte sulla AOA di alimenti di origine vegetale sono rivisti e ridiscussi al fi ne di delucidare gli effetti della temperatura sulla AOA in differenti condizioni di processo

The consumption of minimally processed fruit (MPF) is trendily increasing; this product category retains the qualitative characteristics of the raw material and offers a high convenience to the consumer. Up to now, the research on MPF focused on the study and optimization of processing, aiming to increase the product stability and to extend its shelf-life. The knowledge of the modifications of the functional properties of fresh-cut tissues upon storage and processing is still scarce [1]. Minimal processing for MPF production includes raw material selection, washing, peeling and cutting, pre-treatments, drying, weighing and modified atmosphere packaging (MAP). Few studies investigated the changes of functional properties during processing and storage of MPF but it has been showed that the bioactive compounds content and the antioxidant activity seem to be dependent on the fruit specie, type of pre-treatment, packaging atmosphere and storage time [2]. The effects of traditional and innovative processing operations on the antioxidants (both naturally present and of neo-formation) content and antioxidant activity of MPF and the evolution of the functional properties of these foods soon after preparation and during the refrigerated storage are still unknown. It is important to consider that MPF are living tissues, which show physiological responses to the stresses induced by the technological operations, and the environmental conditions inside the containers in which they are packed. Cutting and peeling operations could determine different effects on the nutritional and health properties of MPF that are not always negative, promoting the so called “wounding metabolism”. Cutting, peeling and the eventual refrigerated storage seem to determine, in some plant tissues (e.g. potato tubers), a cascade of concomitant anabolic and catabolic reactions, such as the flavonols biosynthesis through the induction of the phenylalanine ammonia-lyase enzyme, the well known induction of oxidative enzymes such as polyphenoloxidase and peroxidase, as well as the induction of vitamin C synthesis [3]. Moreover the dipping of fruit pieces in aqueous solutions of stabilizing agents could help the introduction in plant tissue of vitamins, antioxidants and other compounds of nutritional interest. For example, anti-browning pre-treatments with ascorbic acid solutions could determine a fortification of the vitamin C content of fresh-cut apples, as discussed by [2]. A deeper knowledge on the effect of pre-treatments on the content of bioactive compounds and antioxidant activity of MPF and on the evolution of these functional properties during storage in different environmental conditions (atmosphere composition, temperature and light exposure) is essential to obtain specific information on the functionality of MPF.

Lo scopo di questo lavoro è stato quello di mettere a punto metodiche analitiche rapide per la determinazione dei composti fenolici nelle noci. La scelta è ricaduta sull’elettroforesi capillare (HPCE), in quanto è una tecnica largamente utilizzata per la determinazione dei composti fenolici in diverse matrici. Un primo metodo è stato messo a punto mediante HPCE-UV/DAD. I risultati ottenuti sono stati soddisfacenti: è stata infatti ottenuta una separazione dei composti fenolici in 10 minuti, contro i 45 minuti delle metodiche HPLC riportate in bibliografia. La scelta dell’elettrofotesi capillare ha portato ad una serie di vantaggi quali l’uso di quantità estremamente ridotte di solventi e l’utilizzo di mezzi acquosi, con conseguenti vantaggi economici e maggiore sicurezza per l’operatore. La seconda fase del lavoro ha previsto l’identificazione dei composti fenolici mediante HPCE-ESI-microTOF. La separazione, nelle condizioni impiegate per l’interfacciamento con il TOF è stata effettuata in meno di 15 minuti e ha permesso l’identificazione e quantificazione di 9 composti fenolici.

Fresh-cut fruit and vegetable are minimally processed products that have to maintain their quality (appearance, texture, flavour and nutritive value) similar to those of the fresh product. The fundamental principle underlying the quality of these commodities is that they are metabolic active tissues and, as a consequence, show physiological response to preparation procedures as well as to the environment created in the package in which they are enclosed. Minimal processing for fresh-cut potato production includes raw material selection, washing, peeling and cutting, pre-treatments, drying, weighing and packaging. The purpose of this review is to analyse the effects of the different minimal processing steps on the physiology and related quality of fresh-cut potatoes. Particular attention is given to the newest studies on processing innovation and innovative scientific approaches for a better understanding of fresh-cut products as biological systems. In this direction the use of ozone sanitization, natural dipping pre-treatments and/or coatings (e.g. edible film enriched in ascorbic and citric acid), and modified atmosphere packaging at high O2 levels result the most promising and non-invasive techniques for the preservation of fresh-cut potatoes. As far as physiological studies of the product are concerned, fundamental metabolic research for process optimisation and quality assurance is needed. For this aim isothermal calorimetry may provide a versatile tool to conduct fundamental metabolic studies of the effect of different processing steps on the quality and shelf-life of fresh-cut potatoes.

Nell’aprile del 2002 Tareke e collaboratori (1) hanno riportato che molti alimenti sottoposti a cottura contengono livelli relativamente elevati di Acrilammide (AA), conosciuta per essere un composto neurotossico, genotossico e cancerogeno negli animali (2) e classificata dallo IARC (3) come probabile cancerogeno per l’uomo. L’AA è presente ad elevate concentrazioni in certi alimenti fritti, arrostiti e grigliati. Si forma nel corso della reazione di Maillard (4-6) a seguito di degradazione termica dell’amminoacido asparagina che reagisce con i gruppi carbonilici degli zuccheri riduttori, principalmente glucosio e fruttosio. Le patate crude non contengono AA ma elevate quantità dei suoi precursori, zuccheri riduttori e amminoacidi liberi (7), responsabili della formazione di AA durante la reazione di Maillard, ma anche della formazione di composti aromatici e del colore (8). La concentrazione di AA nelle patate cotte dipende dalla quantità di substrati presenti nei tuberi così come dalle condizioni di cottura (9). In particolare le patate fritte (French fries e chips) possono contenere più di 200 µg/kg di AA (10, 11). Temperature e tempi di frittura sono risultati fattori molto significativi per la loro influenza sulla formazione di AA nelle patate così come per lo sviluppo di composti aromatici tipici (12) e di altre caratteristiche organolettiche del prodotto. Tuttavia, la qualità culinaria di tali prodotti, in termini di texture, colore e contenuto in olio, viene raramente considerata. In tale lavoro è stato studiato l’effetto del tempo di frittura e della temperatura sulla formazione di AA ed i cambiamenti di colore, consistenza, contenuto in umidità e olio in patate fritte tipo French fries, ottenute da prodotto fresco utilizzando una friggitrice domestica. Ciò allo scopo di definire appropriate condizioni finalizzate a minimizzare la presenza di prodotti tossici (AA) e al contempo ottenere buone caratteristiche qualitative del prodotto finito.

Il consumo di alimenti di origine vegetale è inversamente correlato al rischio associato all’insorgenza di molte patologie da stress ossidativo. Gli effetti benefici determinati dal consumo di vegetali sono imputati anche alla presenza di antiossidanti. L’assunzione di antiossidanti attraverso gli alimenti è di estrema importanza, visto che gli antiossidanti assunti come supplemento dietetico hanno mostrato effetti controversi. Gli antiossidanti naturalmente presenti nei vegetali possono espletare la loro azione secondo meccanismi diversi e con una diversa efficienza. Per questo motivo una valutazione integrata della capacità antiossidante totale può essere persino più importante della concentrazione dei singoli antiossidanti. Da qui l’esigenza di valutare l’attività antiossidante di un alimento (AOA), cioè la capacità di un alimento di preservare un substrato ossidabile, inattivare una specie radicalica o ridurre un ossidante nell’unità di tempo. I vegetali vengono consumati non solo come alimenti freschi, ma anche trasformati. La AOA può essere ridotta dal processo di trasformazione, a causa di ossidazioni o degradazione termica degli antiossidanti, ma può essere anche incrementata da fenomeni di ossidazione parziale, imbrunimento non enzimatico (NEB) e idrolisi. La temperatura di processo può influenzare la AOA di un alimento secondo diversi meccanismi: (i) modificando la velocità delle reazioni di ossidazione, idrolisi e NEB; (ii) influenzando la solubilità dell’ossigeno o l’accessibilità degli antiossidanti a seguito di danno termico ai tessuti. Quindi una corretta modulazione della temperatura può permettere l’ottimizzazione di un processo di trasformazione nell’ottica di massimizzare la AOA del prodotto finale. Questo lavoro di carattere sperimentale analizza l’effetto della temperatura di processo sulla AOA di vegetali trasformati: surgelati, essiccati, tostati.

The cooking kinetics of spaghetti cooked in boiling water by a traditional method: (TRC) and by microwave (MWC) using an innovative oven suitable for pasta cooking were investigated. The quality of cooked spaghetti was studied as a function of the following cooking parameters: weight increase, total thermal effect and gelatinization extent. Microwave cooking resulted in a time–temperature profile different from that of the traditional cooking process and when the cooking parameters were equal, the microwave cooking was characterized by a lower total thermal effect. In spite of the lower total thermal effect, when the weight increase was equivalent, microwave cooking resulted in more gelatinized and softer products than traditional cooking. The higher gel degree and amylose solubility were not reflected in a higher cooking loss or stickiness; this was due to a more compact gluten network in the outer layer of spaghetti. By modulating the cooking time it was possible to obtain MWC samples with values of weight increase, gel degree and firmness, respectively, equal to the TRC ones; thus different “optimum cooking times” were defined. Sensory panels did not perceive any significant differences between TRC spaghetti and MWC spaghetti samples cooked for different “optimum cooking times” except for the yellow colour intensity, which resulted higher for MWC pasta in agreement with the instrumental analysis data.

Preservare la qualità della frutta lungo tutta la filiera, sia essa corta o lunga, è condizione indispensabile per far fronte alla globalizzazione dei mercati. maggiore attenzione a movimentazione e imballaggi è sempre più richiesta Le dinamiche della globalizzazione dei mercati impongono il trasporto a lunga gittata delle merci, anche di quelle deperibili e, tra queste, la frutta. Allungamento forzato delle epoche produttive, superamento della stagionalità e disponibilità di trasporti veloci hanno portato ad avere sovrapposizione e alternanza nell’offerta di prodotti delle stesse specie coltivate in diverse parti del pianeta, tanto che il consumatore disattento può non considerare la provenienza dei frutti, anche di quelli a lui familiari per abitudini di consumo nei periodi di disponibilità locale.

Research on dough rheology has been carried out for several years. Although many studies have considered the quality attributes of bread made from frozen dough, the use of additives and yeast in the formulation can mask the dough structure changes due to freezing. The objective of this study was to assess, by using texture profile analysis (TPA), Kieffer method and rheometer measurements, the influence of freezing and storage time on dough viscoelastic performance. As the aim of these experiments was only focused on the assessment of dough viscoelastic behaviour, no yeast or additives were incorporated to the samples’ composition. The obtained data showed that the longer the storage time at −18 °C, the lower the dough’s positive viscoelastic performance such as hardness, springiness, adhesiveness, σmax, εH, storage and loss modulus. The observed changes of the non-fermented frozen dough rheological properties after thawing may be attributed to the damage on the gluten cross-linking, mainly produced by the ice crystallization.

For a long time polymers have supplied most of common packaging materials because they present several desired features like softness, lightness and transparency. However, increased use of synthetic packaging films has led to a serious ecological problems due to their total non-biodegradability. Although their complete replacement with eco-friendly packaging films is just impossible to achieve, at least for specific applications like food packaging the use of bioplastics should be the future. The aim of this review was to offer a complete view of the state of the art on biodegradable polymer packages for food application.

MAP has become a widely used food preservation technique, which minimally affects fresh product characteristics, receiving better consumer perception as a natural and additive free techniques. To our knowledge, little data is available in literature regarding the influence of MAP on the shelf-life of packed whole eggs. The aim of this study was to compare some physico-chemical and technological properties of not packed eggs (control) with eggs packed in high barrier plastic pouches with three different atmospheres (air, 100% N2, 100% CO2) during 28 days of storage at 25°C. One day after laying just before packaging and after 1, 2, 4, 8, 15, 21 and 28 days of storage the following determinations were carried out: weight loss and water content, pH, aw, Haugh index (HI), albumen foam stability and texture profile analysis of cylinders of coagulated albumen. MAP was effecting in the reduction of water loss of albumen and of water gain of yolk, while it did not affect aw. As expected, the albumen of control sample showed a constant increase of pH (from about 9 to 10 at the end of storage) because of the loss of CO2 due to its diffusion through the shell pores. Samples packed in air and in 100% N2 did not exhibit this pH increase for all the storage period while the albumen of 100% CO2 eggs showed a rapid reduction of pH reaching values of about 7 after 8 height day of storage. This phenomenon was responsible of the better maintenance of the HI value of sample packed in 100% CO2 compared with samples packed in air and in 100% N2 and with the control one, that showed the most rapid decrease of this parameter. In addition, the foam obtained using the egg white of CO2 sample was about 10 times more stable than the others. Surprisingly thermal coagulation of the albumen of this sample promotes the formation of a very alveolar and soft coagulated structure. From an industrial point of view, the application of this technology (e.g. with controlled atmosphere storage) could permit the substitution of more artificial, complicated, and expensive process commonly applied to change the albumen pH in order to improve the quality characteristics of albumen based products. In the optic of fresh shell eggs commercialization, modified atmosphere packed eggs could represent a tailored innovative food product, with specific characteristics bound to its destination (e.g. fresh shell eggs special for whipping ).