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[EN] In this study, chocolate spreads were designed using oleogels with two oils (olive and sunflower), and hydroxypropylmethylcellulose (HPMC) and xanthan gum (XG), as structuring agents. Thus, the lipid profile of the spreads can be improved by totally or partially replacing the coconut butter used in their preparation. Structural behaviour was analysed using confocal laser scanning microscopy (CLSM), small amplitude oscillatory rheology, and a spreadability test. A Free Choice Profile analysis was performed by consumers to determine the sensorial attributes that described the chocolate spreads. The results showed that the oleogels conferred consistency to the spreads because of the network formed by HPMC and XG. However, while coconut butter replacement at 50% gave a similar structure to the control spread, 100% replacement resulted in less homogeneous spreads. This trend might be attributed to the chemical compatibility between the oleogel-coconut butter, which led to stronger systems. Sensory evaluation showed that chocolate spread replaced by sunflower oleogel at 50% presented sensory attributes like the control spread with "creamy appearance", "creamy texture", and "cocoa flavour". Therefore, using oleogels can be a viable and healthy alternative to replace the saturated fat present in chocolate spreads., The authors would like to thank Universitat Politecnica de Valencia by FPI-UPV 2017 grant and the project RTI2018-099738-B-C22 from the 'Ministerio de Ciencia, Innovacion y Universidades'.

[EN] In this study, the effect of two hot air drying conditions (40 degrees C for 23 h and 60 degrees C for 9 h) on the content, antioxidant activity, microstructure, and luminescence properties of persimmon carotenoids in three ripening stages was studied. Based on the results from total carotenoids content and HPLC analysis, the carotenoid's content increased with the advance of ripening, highlighting the beta-cryptoxanthin fraction. In addition, drying treatments did not affect the carotenoid content and profile but decreased the antioxidant activity. Microstructural studies showed that the ripening progress and/or drying treatments, led persimmon tissues to lose integrity, allowing the diffusion of carotenoids and their degradation. Photoluminescence measurements evidenced the synthesis of beta-cryptoxanthin during the fruit ripening. After drying, a new emitting specie at 340 nm was attributed to the carotenoid's isomerisation while the emission at 500 nm experienced a shift that was related to the formation of thermal degradation products. Both facts could explain the loss of antioxidant activity in persimmon submitted to drying treatments. In this sense, photoluminescence, in combination with spectro-photometric, chromatographic and structural techniques, helps to understand the phenomena caused by both, ripening and drying treatments, in the persimmon's carotenoids fraction., The authors thank the Ministerio de Ciencia, Innovacion y Universidades for the financial support given throughout Project RTA201700045-C02-02. They would also like to thank Phillip Bentley for assistance in correcting the manuscript's English.

[EN] Blackcurrant pomace is a by-product with bioactive compounds and dietary fibre, which can be used as ingredient to elaborate bakery products. However, its high content of fibre results in techno-functional problems affecting texture and sensory properties. We hypothesised that the use of different chemical leavening agents can counteract the negative effects of pomace addition improving the quality of the final product. Citric acid, sodium acid pyrophosphate, and glucono-delta-lactone were used as leavening agents in combination with sodium bicarbonate (encapsulated and free). A micro-baking simulation showed the expansion of the bubbles in the batter. In the cakes, the structure, texture, colour and sensory profile were studied. Cakes prepared with pyrophosphate (regardless bicarbonate type) and glucono-delta-lactone (plus free bicarbonate) incorporated more air, which led to bigger gas cells and a softer instrumental texture. These cakes were perceived as brittle and spongy. All the formulations were acceptable according to an untrained sensory panel., The authors are grateful to Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA-Spain) for financial support through the BERRYPOM - Adding value to fruit processing waste: innovative ways to incorporate fibres from berry pomace in baked and extruded cereal-based foods project included in the ERA-NET SUSFOOD programme. They would also like to thank Phillip John Bentley for his assistance in correcting the manuscript's English. They would also like to thank Phillip John Bentley for his assistance in correcting the manuscript's English.

Authors acknowledge the financial support of the Spanish Ministry of Economy and Competitiveness (Project AGL2014‐52928‐C2‐1‐R), the European Regional Development Fund (FEDER) and Generalitat Valenciana (Project Prometeo 2017/189).

[EN] Pomace from fruit juice production is a by-product with a high fibre and bioactive compound content. It is commonly used as animal feed, so using it in food brings added value. The present study assessed the effect of using black currant and aronia pomace to replace either part of the flour, fat or sugar in sponge cakes. Batters in which sugar was replaced showed the highest viscosity. On the other hand, flour replacement led to batters with the lowest viscosity and gave place to softer cakes with fewer but larger-sized air cells. Sugar replacement conferred greater hardness and a larger number of small air cells. In general, fat replacement gave rise to intermediate crumb texture and structure properties in comparison with flour and sugar replacements. In vitro starch digestion showed that the flour-replaced sponge cakes possessed the lowest hydrolysis index and glycaemic index values. The sponge cakes with the different replacements were well accepted by consumers, who expressed a high level of buying intention for all of them., The authors are grateful to Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA-Spain) for financial support through the BERRYPOM - Adding value to fruit processing waste: innovative ways to incorporate fibres from berry pomace in baked and extruded cereal-based foods project included in the ERA-NET - SUSFOOD programme. The German contribution was funded through the Federal Ministry of Education and Research via PTJ (grant 031B0004).

Increasing the protein content of a food is an effective way to deliver enhanced satiating signals to the consumer. Protein structures are related to their breakdown properties under gastric conditions and understanding their in vitro proteolysis could provide valuable information on their contribution to satiating ability. Four different yogurts were formulated with double the amount of protein by adding extra skimmed milk powder (MP), whey protein concentrate (WPC), calcium caseinate (CAS) or a blend of whey protein concentrate and calcium caseinate (MIX). Their rheological behavior and light microscopy and SDS-PAGE data were analyzed at different times of oral plus gastric in vitro digestion (0, 30, 60 and 120 min). The yogurts with added whey protein (WPC and MIX) maintained high consistency index values throughout in vitro digestion, which is related to increased gastric distension and to an extended feeling of fullness. In addition, the rapid gastric emptying of whey proteins in a more unaltered form than casein may result in a stronger increase in postprandial plasma amino acid concentration, increasing the satiating signals. Consequently, adding whey protein to the formulation of yogurts can enhance satiety, despite processing steps such as thermal treatment and fermentation.

[EN] The use of persimmon variety "Rojo Brillante", has seen a great expansion in recent years. Its production is associated with substantial amounts of post-harvest waste, therefore, development of products that allow its valorisation are of great interest. In this study, a freeze-drying technique was used to obtain a high quality product. Freeze-dried samples were conditioned in a range of water activities (0.113-0.680) at 20 degrees C at equilibrium, allowing for products of different water content. Water sorption isotherms were determined from persimmon slices, with BET (Brunauer, Emmett, and Teller) and GAB (Guggenheim, Anderson, and de Boer) models applied to the sorption data. The glass transition was analysed using differential scanning calorimetry (DSC); the Gordon & Taylor equation modelled the water plasticisation effect. Results confirmed a critical water activity (CWA) of 0.165 and a critical water content (CWC) of 0.0312 g water/g product. Below these critical values, the glassy state of the amorphous matrix and the crispness were guaranteed. This consequently avoids an increase in the rate of deterioration reactions, texture and colour changes, and the loss of the fruit bioactive compounds., The authors thank the Ministerio de Ciencia, Innovacion y Universidades for the financial support given throughout Project RTA2017-00045-C02-02. They would also like to thank Phillip Bentley for assistance in correcting the English manuscript.

The physico-chemical and microstructural changes of &ldquo, Rojo Brillante&rdquo, persimmons in two maturity stages (S1 and S2) were evaluated during air drying. The maturity stage influences moisture loss. A Moisture level of approximately 50%, a limit at which persimmons are considered semidried, was reached after 21 and 28 days for S1 and S2, respectively. Shrinkage resulting from water removal led to secondary epidermis formation concomitantly to internal flesh gelling, which was related to moisture loss and water activity changes of each fruit part. The thicker epidermis and the lower volume of gelled area inside the S1 fruits led to harder fruit compared to the S2 fruits. The microstructural study revealed parenchyma degradation during drying in both the outermost area (secondary epidermis) and internal flesh, and this process was faster in S1 than in S2. The second peel presented hollows, generated by water outflow, which were bigger in S1 and explained the faster internal dehydration in S1. During drying, slight browning occurred, as reflected in the declining color parameters (L*, h* and C*). Water removal led to soluble solids tannin reduction to non-astringency values on day 28.

The influences of four different cooking methods-pan, ohmic, vacuum and sous vide-were studied with regard to the microstructural, sensorial and physicochemical characteristics of pork meat. The end point temperature to all cooking methods was 70 °C. Pan cooking resulted in a softer meat with higher overall liking by the consumers, and ohmic cooking produced firmer (p .05) meats and myofibrils, with higher alignment compared to the pan-cooked meat as well as a golden colour. Sous vide-cooked meats were perceived as insipid, while vacuum-cooked meats showed loss of structure and were perceived as drier (p .01) and paler (p .01). No statistically significant differences were found for cooking loss and water-holding capacity (p .05). The results suggest that consumers preferred pan-cooking, as they described these samples as juicy, tender and tasty. Ohmic-cooked meat, which required shorter cooking times, showed similar characteristics to pan-cooked meat and could be used as alternative to pan cooking in the catering industry.

Protein is the most effective food macronutrient providing a satiating effect. Thus, formulating dairy foods with increased protein contents can help to modulate food intake. Oral perception cues also contribute an increased perception of satiating capacity when the oral residence time and handling are longer and more laborious. In the present work, yogurts were prepared with double skimmed milk powder (MP) and whey protein (WP), as well as a control (C) without extra protein. Three more samples were prepared by adding 2% of a physically modified starch to each (CS, MPS and WPS, respectively), in order to increase the consistency and impart creaminess. Rheological tests were used to characterize the flow and viscoelastic properties of the samples before and after saliva treatment, and their microstructure was observed. Finally the differences in sensory perceptions elicited by the samples were related to consumers' expected satiating capacity and liking scores. Before in vitro oral digestion, MP showed denser areas than C; in WP, two protein networks could be distinguished. In the samples with added starch, starch granules were embedded in the protein networks. After in vitro oral digestion the protein tended to aggregate; the starch granules maintained their structure indicating that they were not broken down by the saliva. These observations were related to the samples' rheological behavior. The sensory graininess, lumpiness and grittiness detected in the WP samples could be linked to the aggregation of whey protein and the formation of two different protein networks. All the added-starch samples elicited creamier and denser sensations than their counterparts without starch. MP with starch was scored as the most satiating and best-liked yogurt sample., The authors are grateful to the Spanish Ministry of the Economy and Competitiveness for financial support (AGL2012-36753-C02) and gratefully acknowledge the financial support of EU FEDER funds. They would also like to thank Mary Georgina Hardinge for assistance in correcting the English manuscript.

Much research has been done to explain the action of emulsifiers during breadmaking, but there is still plenty unknown to elucidate their functionality despite their diverse chemical structure. The aim of the present study was to provide some light on the role of emulsifiers on air incorporation into the dough and gas bubbles progress during baking and their relationship with bread features. Emulsifiers like diacetyl tartaric acid ester of monoglycerides (DATEM), sodium stearoyl lactylate (SSL), distilled monoglyceride (DMG-45 and DMG-75), lecithin and polyglycerol esters of fatty acids (PGEF) were tested in very hydrated doughs.Emulsifiers increase the maximum dough volume during proofing. Emulsifiers increase the number of bubbles incorporated during mixing, observing higher number of bubbles, particularly with PGEF. Major changes in dough occurred at 70 K when bubble size augmented, becoming more heterogeneous. DMG-75 produced the biggest bubbles. As a consequence, emulsifiers tend to increase the number of gas cells with lower size in the bread crumb, but led to greater crumb firmness, which suggested different interactions between emulsifiers and gluten, affecting protein polymerization during baking.The progress of the bubbles during baking allowed the differentiation of emulsifiers, which could explain their performance in breadmaking. © 2018 Society of Chemical Industry.

Blackcurrant pomace is a by-product from fruit juice production, which is rich in polyphenols and dietary fibre. When added to bakery products, its high fibre content has detrimental effects on dough/batter viscosity and on the texture and the structure of the final product. In this study, wheat flour extruded at different temperatures was used to replace 50% of wheat flour in a muffin formulation to counteract these detrimental effects. In addition, the effect of blackcurrant on the glucose release during in vitro digestion was analysed. The extrusion treatment of the flour caused a disruption of the starch granules, and affected starch characteristics such as water binding capacity and swelling. Its incorporation in muffins did not produce important differences in texture, nor in consumer acceptance, compared to a standard formulation. Moreover, the addition of blackcurrant counteracted the hyperglycaemic effect of pre-gelatinised starch.

Manifestation of flesh browning while commercialising Rojo Brillante persimmon is one of the main causes of postharvest loss. It is known that mechanical damage is a decisive factor for browning development and that astringent fruit is less sensitive to this disorder than fruit submitted to a CO2 deastringency treatment under standard conditions (24 h, 95% CO2, 20 C). However, there is no information available about the mechanism behind this alteration. In the present study, we evaluated the effect of treatment with high CO2 concentrations applied for 0 40 h on the incidence of mechanical impactinduced flesh disorders using biochemical, chromatographic and microstructural techniques. Our results show that the longer the CO2 exposure, the higher the incidence and the greater the severity browning. A deastringency treatment with CO2 results in O 2 accumulation in fruit, which is greater the longer treatment is. However, mechanical damage triggers the browning manifestation, resulting in the accumulation of both O 2 and H2O2. In this oxidative stress state, which must be greater as higher the level of O 2 previously accumulated in the deastringency treatment, insoluble tannins initially uncolour, undergo an oxidation process and turn red-brown, observed as flesh browning. Moreover, we identified a new disorder, pinkish-bruising , which is manifested in astringent fruit. The mechanism of this alteration, also associated with mechanical damage, seems similar to that of browning, but the oxidation process would affect soluble tannins., This study has been supported by the Spanish 'Ministerio de Economia y Competitividad (Project INIA-RTA 2010-00086-00-00) and FEDER Program from the EU. We thank to 'D.O. Kaki Ribera del Xuquer' for his support for these studies. We thank Ph.D. Takashi Tanaka (Nagasaki University) for his support during the chromatographic analysis. Ph.D. Cristina Besada is contracted by the 'Regional Ministry of Education of the Valencian Community'.

[EN] The first aim of this study was to observe the effect of adding dairy proteins and reducing the cream content in order to obtain healthier dairy desserts for use in weight management. The extra-whey protein low-cream sample had the densest, firmest matrix, which is related to increased satiety. The second aim was to investigate the in vitro gastric digestion behavior of whey and casein proteins in a heat treated semisolid real food. The extra-casein protein sample matrix broke down more slowly than the others because the caseins clotted at the gastric pH. Despite being heated, the whey proteins in the panna cottas were more resistant to pepsin digestion than caseins; this is related with a higher satiety capacity. These findings suggest that the combination of reducing fat content (to obtain a reduced energy density product) and adding whey protein (to increase satiety capacity) allows obtaining dairy desserts for weight management., This work was supported by the Spanish Ministry of the Economy and Competitiveness (AGL2012-36753-C02) and by EU FEDER funds.

The authors are grateful for the economic support received from Universitat Politecnica de Valencia - project PAID-06-09-2871, and Generalitat Valenciana - project GV-2010/038. The authors also thank the Universitat Politecnica de Valencia for the FPI grant given to Maria Hernandez Carrion.

Vacuum Impregnation (VI) is a non-destructive technology, used to introduce external liquids, in the porous structures of food matrices favored by the action of hydrodynamic mechanism as promoted by pressure changes. Previous studies evidenced the potentiality to apply VI to zucchini [2] but no systematic studies have been carried out yet. Aim of this study was to investigate the effect of VI by using mixed solutions containing structuring ability components (maltodextrins, salt and CaCl2) with on quality and microstructural properties of zucchini. Slices of zucchini (0.5-cm thick) ( Cucurbita pepo, L.) were subjected to VI treatments. VI solutions with different solutes composition were investigated: maltodextrines, NaCl and CaCl2 were used to prepare single (1 solute) or mixed (2 and 3 solutes) VI solutions Samples were analysed for total solids, soluble solids, salt and [Ca] content, textural properties (shear force, relaxation test), sensory and microstructure (Cryo-SEM). Mass balance (Solute Gain/Loss, Water Gain/Loss) was also computed. The composition of the VI solution affected mass transfer. A significant change in the textural properties was observed in zucchini processed with VI solutions containing NaCl and MD; the presence of CaCl2 in the VI solution in combination with the other solutes, was able limit the hardness loss and when alone even to determine an hardening effect. Cryo-SEM analysis highlighted a different effect on microstructure of the vegetable tissue due the use of the single or mixed VI solutions. The use of VI mixed solutions made with MD, NaCl and CaCl2 to process zucchini allows to favour solute and water gain while limiting textural and microstructural changes

The effect of calcium lactate on the structure (determined by microscopy), texture (penetration test), pectinmethylesterase activity and polygalacturonase activity of fresh-cut “Flor de Invierno” pears stored for 3 weeks at 4 °C was studied. The results showed that calcium lactate reinforced the structure of the fruit maintaining the fibrilar packing in the cell walls and the cell-to-cell contacts. This reinforcement counteracted the increase of both pectinmethylesterase and polygalacturonase activities. These results were reflected at a macroscopic level in an improvement of the texture of the calcium-treated pears. Calcium lactate could therefore be used to improve the structural integrity of fresh-cut “Flor de Invierno” pears.

Dry-cured ham, “Protected Designation of Origin (PDO)” Teruel, is a high quality meat product processed using a traditional dry-curing procedure. The objective of this paper was to study the microstructure of the Biceps femoris and Semimembranosus muscles during “PDO Teruel” dry-cured ham processing using electron microscopy techniques (Cryo-SEM, SEM and TEM). The Semimembranosus and Biceps femoris muscles from raw ham show the typical structure of muscle tissue in meat. The muscle fibres appear firmly attached to one another by the endomysial connective tissue; the myofibrils inside the cells are strongly attached to each other and to the sarcolemma. In raw ham, the typical structural elements that constitute the sarcomere can be observed by TEM. Important microstructural changes are observed following salting; reflected in the fact that the Z-disks inside the myofibrils are no longer in line and there is important degradation of the cell membranes in this stage. At the end of the process, an accumulation of solutes, which could be products from proteolysis occurring mainly in the last stage of ripening, could be observed in both muscles. Thus the proteolysis and dehydratation phenomena that take place during “PDO Teruel” dry-cured ham processing occur at an ultrastructural level, and this is the basis to produce a product with the sensory features appreciated by consumers.

Red sweet peppers are good sources of antioxidant compounds, such as fibre and carotenoids. Therefore, innovative products that may replace traditional ones, such as white sauces enriched with red sweet pepper, should be developed to improve their functionality. The aim of this work was to study the rheological behaviour, microstructure, syneresis, colour, sensory characteristics and consumer acceptability of new white sauces enriched with red sweet pepper. The results of the rheological studies (viscoelastic behaviour) showed that in the available frequency window all the sauces showed a predominance of the elastic modulus versus the viscous modulus. The effect of incorporating red pepper on the rheological properties depended upon the type of starch used. Microstructure of native starch sauces showed a complex matrix composed of protein and amylose and amylopectin leached from the granules that have been disintegrated during the sauce elaboration. Fat globules were homogenously dispersed and associated with the protein phase. Modified starch sauces showed more swollen starch granules compared with native starch sauces and a protein matrix stabilising the fat globules. All the sauces exhibited considerable intrinsic autofluorescence due to the presence of carotenoids from the red pepper. Consumers scored the modified starch sauces regardless of the starch concentrations based on their highest overall liking and found them beneficial for health. Therefore, new white sauces with high nutritional value, high acceptability, good rheological properties and stability against syneresis could be formulated using red pepper and modified starch., The authors wish to acknowledge the Spanish Ministry of Science and Innovation for their financial support (Project AGL2011-30064-C02-02) and to the Universitat Politecnica de Valencia (UPV) for the FPI grant awarded to Maria Hernandez-Carrion. Moreover, the authors wish to thank Elsevier for assistance with the English manuscript.

The objective of this paper was to study the main chemical and microstructural changes in squid proteins during processing as a frozen batter-coated product using different coatings. Protein bands of the squid and of the batters used for coating were studied using SDS-PAGE. It is concluded that it is not only the proteins of the layer of batter, which are directly exposed both to the frying oil and to freezing temperatures, that deteriorate during the preparation process, the protein fraction of the squid substrate, mainly the myofibrillar proteins, is also degraded. At a microstructural level, big voids are generated during freezing as a consequence of the packing of the fibres, although the size of these voids decreases after final frying. After this step of the process, the central sarcoplasm is still visible but has been altered by coagulation of the sarcoplasmic proteins and the sarcolemma is observed to be separate from the myofibrillar package.

Cryo-Scanning Electron Microscopy was used to study the microstructure of frozen batter-coated products prepared by an innovative process. This recently patented process makes possible to eliminate the industrial pre-frying stage that coagulates the batter layer and replace it by coagulation in a hot water bath at 70 °C followed by a short thermal treatment in a microwave oven. The innovative process is made possible by adding methylcellulose to the batter formula. The microscopic observations show that adding this cellulose derivative to the batter formula produces a microstructural matrix that favors the coating–food interaction. After immersing the batter-coated product in hot water, the coating was found to have developed a consolidated structure. This was further reinforced by the microwave oven step, allowing the product to be handled without deteriorating. Maintenance of good adhesion between the coating and the food (squid) surface was observed in the final fried product as well.

Osmotic dehydration (OD) permits the preservation of foods via a decrease in water content and an increase in solute concentration. Osmotically dehydrated fruits such as apple are suitable for the manufacture of desserts, cakes, salads, yoghurts, etc. Different microstructural and engineering aspects of OD are already known, but its effects on enzymatic activity are still unknown. This study analyses the activity of polyphenoloxidase (PPO) in fresh Granny Smith apples and the effect that OD by immersion in sucrose-saturated syrup has on this activity. The low PPO activity found in the edible parenchyma of osmotically dehydrated apples is attributed to penetration by the osmotic agent and flooding of the intercellular spaces, which produces a low moisture content and a limited O2 concentration in the immediate environment of the enzyme. These results show that OD prevents enzyme-substrate interaction. Thus the low PPO activity would reduce browning of this type of product.  2005 Society of Chemical Industry

Calcium plays a very important role in the maintenance of quality in vegetable foods and it is used as a texturing agent to preserve the structure of minimally processed vegetables. The osmotic dehydration (OD) of 'Granny Smith' apple parenchyma by immersion in a sucrose solution allows us to obtain products with sensorial characteristics similar to those of fresh products, but it produces a loss of cellular integrity. Here we study the use of calcium as a possible preservative for the microstructural integrity of the product during OD, as well as to test whether cellular permeabilization improves the impact of calcium on the edible parenchyma of the 'Granny Smith' apple. Sodium dodecyl sulfate (SDS) has been used for convenience as a permeating agent although we recognize this may not be used in practice. The microstructure of the OD apple treated with calcium chloride and with SDS has been compared with fresh apple by means of light microscopy, transmission electron microscopy and low temperature scanning electron microscopy. The results show that calcium has a protective effect on the structural integrity during OD: it strengthens the cellular walls cements, avoids cellular collapse and protects protoplasts from plasmolysis. Although SDS favours calcium penetration, its use is not advisable since it encourages the destructuring effect of the OD and counteracts the consolidating effect of calcium.  2004 Society of Chemical Industry

The present paper studies the influence that batter ingredients (wheat flour, corn flour, salt and leavening agent) have on fat content and oxidative degradation of the lipid fraction of deep-fried frozen battered squid. The use of a leavening agent significantly increases the fat content during frying; the generation of gas cells where oil easily lodges is the most important event observed by scanning electron microscopy when this additive is used in the formulation. The addition of salt in the formulation also increases fat content, but replacement of wheat flour by corn flour decreases significantly the oil content of the battered squids. The acidity index values indicate a relatively low degree of hydrolysis for all the batters studied. The batter formulation influences the degree of oxidation of the lipid fraction of the deep-fried products; the battered product with leavening in its formulation shows a lesser oxidation (P

Persimmon cv. Fuyu is chilling-sensitive and manifests chilling injury symptoms, flesh gelling and fruit darkening, during cold storage and subsequent shelf life. The objective of this study was to evaluate the effect of short-term high CO2 treatments on chilling injury manifestation of Fuyu . Short-term high CO2 treatments consisted in maintaining fruit in a 95% CO2 atmosphere for 0, 12, 24 or 36 h before storage at 1 C. After 35 d and 50 d of low-temperature storage and after subsequent shelf-life periods of 5 d at 20 C, fruit quality and microstructural changes of flesh were evaluated. Our results showed that shortterm high CO2 treatments alleviate the main chilling injury symptoms, flesh gelling and fruit darkening. The longer the treatment, the greater chilling injury alleviation becomes. The microstructural study revealed that flesh gelling is associated with a complete disruption of cell walls and membranes, which led to the total loss of the initial parenchyma structure. Short-term high CO2 treatment alleviated flesh gelling by preserving the integrity of cells walls and plasmalemma., This study has been supported by the Instituto Valenciano de Investigaciones Agrarias (Generalitat Valenciana. Conselleria de Presidencia y Agricultura, Pesca, Alimentacion y Agua).

The effect of frying on the microstructure of frozen battered squid rings was studied by means of scanning electron microscopy and low temperature scanning electron microscopy. It was observed that many microstructural modifications take place in the food substrate – squid – and in the layer of batter. In the fibres of squid that has been battered, frozen and fried, the central sarcoplasm is still visible but altered by coagulation of the sarcoplasmic proteins; the fibres of the muscle tissue also become more closely packed during the frying process, owing to loss of interfibrillar water by evaporation. It is seen that absorption of fat during frying – which may be more than 40% (w/w) – takes place not only in the layer of batter but also in the squid ring; the fat also draws other components of the batter, such as starch, to the denatured squid surface. After the final frying process, gas cells, formed by release of the gases generated, and consolidation of the microstructural components of the coagulated batter are observed. The structure of the solid fried batter matrix is basically formed by proteins and starch granules.

A study was made of the effect of pickling on the texture of carrots. Five different devices and tests were applied: puncture with needle, penetration with sphere or cylinder, texture profile analysis (TPA) and Warner–Bratzler knife. Phloem and xylem areas of samples were tested separately when possible. The results indicated a considerable difference in texture between unprocessed and 1 day pickled carrots. Some of the tests were able to discriminate between phloem and xylem in the samples. None of the tests applied was able to detect differences in texture between samples taken after 1 day of pickling and samples taken at any other point in the pickling process. Scanning electron microscopy (SEM) observations showed structural differences between phloem and xylem which reflected corresponding differences in texture. Some penetration of salt could be seen after 1 day of the pickling process, and a massive penetration of salt at the end of it. © 2001 Society of Chemical Industry

[EN] The microstructural, physical, and sensory properties of low-fat sauces made with different starches, soy protein, and inulin as a fat replacer were analyzed. Gluten-free waxy starches-rice and corn-were selected as well as soy protein to obtain sauces suitable for celiac and lactose intolerant consumers. Light microscopy was used to visualize the swollen starch granules dispersed in a protein-amylopectin-inulin phase. Inulin seemed to limit protein network development, which was related with a higher dispersion of starch granules within the sauce matrix. Therefore, the sauces made with inulin had a lower apparent viscosity (¿app) values (P < 0.05) in comparison with oil sauces. The sauces made with rice starches also exhibited a lower viscosity (P < 0.05) since these granules did not swell as corn granules do. All the sauces had a remarkable physical stability since there were no syneresis phenomena and color did not change significantly (P < 0.05) after 15 d of refrigeration storage (4 °C). Finally, the sensory test suggests that oil could be substituted by inulin in the preparation of low-fat sauces since no significant differences (P < 0.05) in texture and flavor were found. These results encourage further research to optimize the formulations of these types of alternative white sauces. Practical Application: Nowadays there is a great demand of ready-to-eat products due to new consumptions habits. In this context, it would be interesting to develop low-fat sauces with inulin that could be used in this type of products improving their nutritional profile. The requirement of processed food for specific groups of population, such as celiac and lactose intolerant consumers, makes it necessary to use gluten free starches and soy protein in the formulation of sauces. The characterization of structural, physical and sensory properties is required to understand the product acceptability and its behavior during its shelf life. © 2012 Institute of Food Technologists®., The authors are grateful for the FPU grant awarded to L. M. Guardeno and the economic support received from Univ. Politecnica de Valencia-project PAID-06-09-2871 and Generalitat Valenciana-project GV-2010/038.

[EN] High pressure homogenization (HPH) is a novel non-thermal preservation technology, which can improve the microbiological quality of products without affecting their stability. The main objective of this paper is to study the influence of different HPH treatments on the structure of a sauce (an egg/dairy emulsion). in order to obtain the higher physicochemical stability. The oil-in-water emulsion was stable up to 100 MPa with the oil droplets surrounded by several layers of natural emulsifiers. Critical pressures, between 150 and 250 MPa, produced a destabilization of the emulsion thus causing a separation of phases. A coalescence phenomenon progressively occurred when pressure increased. This phenomenon was due to the loss of the natural emulsifier barrier. Changes on the electrophoretic pattern were also observed at high pressure levels, showing an insolubilization of proteins. Lipid fraction was observed to be chemically stable after the HPH treatment. (C) 2011 Elsevier Ltd. All rights reserved., Authors want to thank to the European Commission for the financial support (Project FP6-FOOD-023140), to the Ministerio de Educación y Ciencia (Spain) for the grant awarded to the author R. Marco-Molés, and to the Ministerio de Ciencia e Innovación (Spain) for the financial support (AGL2007-30951-E). Finally, authors thank to the University of Bologna (Italy) for providing the HPH treated samples.

The demand for foodstuffs which are easily and fast prepared has increased considerably in recent years. Sauces are often used in this kind of products and their formulation usually includes polysaccharides (starch and/or gums) as thickening agents [1]. Sauce microstructure gives information about the components arrangement and how it affects physical and chemical properties such as viscosity. The aim of this work is to study the effect of different thickeners and salt concentrations on the microstructure of model systems.

The aim of this work was to study the main chemical changes in the protein fraction (SDS-PAGE) and the microstructure (TEM) of whole liquid egg treated with HPH and stored one week at 4°C. In the electrophoretic study, no changes were observed after the treatments neither after one week of refrigerated storage in the water-soluble pro - teins of the samples, indicating that no proteolysis was produced. The typical structure of the egg lipoprotein matrix was maintained after the HPH treatments and one week of refrigerated storage. However, a progressive disaggregation of the protein granules was observed, especially when high intensity HPH treatment was applied. It was attributed to the HPH treatment and the microstructural changes observed could affect the functionality of the whole liquid egg when it is used as an ingredient in foodstuffs.

Guardeno L.M., Quiles A., Llorca E., Pertusa J., Hernando I. (2013): Effect of microwave thawing on microstructure and physicochemical stability of low fat white sauces made with soy protein. Czech J. Food Sci., 31: 568–574. The microstructural and physicochemical stability of white sauces made with soy protein and modified waxy maize starch was evaluated after subjecting them to a freezing-thawing process in a conventional or microwave oven. The microstructure of sauces revealed a structured matrix of soy protein and starch polymers where fat globules and swollen starch granules remain dispersed. Both thawing methods affected the fat globule size and morphology but they did not affect the starch granules. The SDS-PAGE analysis did not show any apparent changes between sauces thawed by both methods. Moreover, a similar pattern was found in the soy protein isolate used as a raw material indicating that this type of protein was also stable to the cooking process. There were no significant differences ( P > 0.05) in the reducing power of the sauces regardless of the thawing method used. However, the acidity index and the k 232 parameter were significantly higher ( P 0.05) were found among different frozen storage periods. In conclusion, the formulation of the sauce is appropriate to develop low fat, vegetarian meals which can be subjected to frozen storage and microwave reheating.

Proteins, lipids and structural changes in white sauces after being stored at -18°C and thawed by microwave and conventional oven were studied in this work. The total crude and soluble protein fractions were quantified by N-Kjeldahl. The acidity grade and oxidation spectrophotometric parameters (k 232 and k 270 ) were used to analyse the lipid fraction. In addition, confocal scanning laser microscopy (CSLM) was used to study the structure of the sauce. The results showed that the total crude protein fraction increased in the thawed samples if compared to the freshly-prepared samples, mainly when microwave oven was used. However, the soluble protein fraction did not vary significantly ( P < 0.05) among the different samples. Regarding the lipid changes, the acidity index did not show significant differences among the samples. K 232 values of the microwave-thawed samples differed significantly from the freshly-prepared and the conventional-thawed samples. Furthermore, k 270 values were significantly different between the samples thawed using the conventional oven and the freshly-prepared ones. CSLM images showed degradation of the starch granules and an increase of size in the fat globules due to thawing.