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Four rotation sequences consisting of ungrafted tomato cv. Durinta – melon cv. Paloma or tomato grafted onto the resistant rootstock ‘Aligator’ – melon grafted onto the resistant Cucumis metuliferus accession BGV11135, and in reverse order, were conducted from 2015 to 2017 in a plastic greenhouse infested or not with Meloidogyne incognita to determine the plant tolerance (T), the minimum relative crop yield (m) and fruit quality. The relationship between M. incognita densities in soil at transplanting (Pi) of each crop and the crop yield was assessed and T and m were estimated by the Seinhorst’s damage model. In addition, the volume and the number of nuclei of single giant cells and the number of giant cells, its volume and the number of nuclei per feeding site in susceptible tomato and melon were compared to those in the resistant tomato and C. metuliferus 15 days after nematode inoculation in pot test. The relationship between the Pi and the relative crop yield fitted the Seinhorst’s damage model in both ungrafted and grafted tomato and melon, but not for all years and cropping seasons. The estimated T for ungrafted and grafted tomato did not differ but m was lower in the former (34%) than the latter (67%). Sodium concentration in fruits from ungrafted but not from grafted tomato increased with nematode densities in spring 2015 and 2016. The estimated ungrafted melon T did not differ from the grafted melon cultivated in spring, but it did when it was cultivated in summer. The relative crop yield of ungrafted melon was lower (2%) than the grafted cultivated in spring (62%) and summer (20%). Sodium concentration in melon fruits from ungrafted plants increased with nematode densities. No variations in fruit quality from grafted melon cultivated in spring were found, although less dry matter and soluble solid content at highest nematode densities were registered when it was cultivated in summer. Lower number of giant cells per feeding site was observed in both susceptible tomato germplasms compared to the resistant ones but they were more voluminous and held higher number of nuclei per giant cell and per feeding site.

Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques were used to study the effect of four food additives, agar, alginate, lecithin and glycerol, at three different concentrations, 0.5, 1 and 1.5%, on the molecular structure of potato puree prepared from commercial potato powder. Vibrational spectra revealed that the amylose-amylopectin skeleton present in the raw potato starch was missing in the potato powder but could be fully recovered upon water addition when the potato puree was prepared. FTIR peaks corresponding to water were clearly present in the potato powder, indicating the important structural role of water molecules in the recovery of the initial molecular conformation. None of the studied puree samples presented a crystalline structure or strong internal order. A comparison of the FTIR and XRD results revealed that the additives exerted some effects, mainly on the long-range order of the starch structure via interacting with and changing -OH and hydrogen bond interactions.

The different intensities of common culinary techniques (boiling, baking and microwaving) produce several changes that reduce the nutritional and physical properties of potatoes. This study evaluated the effect of those cooking methods on the quality of commercial potato tubers (Agata, Kennebec, Caesar and Red Pontiac). The higher weight losses were obtained for baking, but the potato softening depended on the cultivar. Color losses were independent of the intensity of the treatment; however, microwaving promoted a prompt starch gelatinization with respect to the other methods. The resistant starch retention of baking and microwaving was higher than that of boiling, and the maximum retention of bioactive compounds was obtained with the lower core temperature during boiling, as well as higher temperature and shorter baking time and the lower power and longer microwaving time. Principal component analysis revealed significant relationships between the instrumental and functional properties of cooked potatoes. (C) 2015 Published by Elsevier Ltd.

The aim of this work was to investigate the effect of using ultrasound or edible coating as a possible alternative to blanching on the quality of vacuum-packaged potato strips. The treatments assessed were blanching (85 °C, 3.5 min), coating with 20 g L-1 alginate and sonicating (40 kHz, 5 min) in an ultrasonic bath containing a 20 g L-1 citric acid solution. Vacuum-packaged samples were stored up to 12 days at 3 ± 1 °C. The pH, polyphenol oxidase (PPO) activity, sugars and microbial load were assessed. Also, the colour, shear-force and dry matter of the treated and fried potato strips as well as the oil adsorption and acrylamide after frying were evaluated. The PPO activity of the treated samples was not significantly different over time (p > 0.05). The treatments applied did not affect the attributes of the fried potato strips over time; there were no significant changes in oil absorption, acrylamide content or colour (p > 0.05). However, the visual quality of sonicated packaged potato strips was significantly better than that of the other treatments after storage. The loss of the texture of blanched potatoes was remarkable (p < 0.05) before and after frying. Sonicated samples maintained mesophilic bacteria counts better than blanched and alginate coated vacuum-packaged potato strips.

The effects of agar, alginate, lecithin and glycerol on the rheological properties of commercial potato puree were investigated and interpreted in terms of starch microstructural changes, and the applicability of the Cox-Merz rule was evaluated. Each additive was applied separately at two concentrations (0.5 and 1%). Microscopic observations revealed more swollen starch aggregations in lecithin and glycerol compared with those of potato puree and agar, consequently affecting the rheological properties of potato puree. All samples exhibited shear thinning non-Newtonian behaviour. Rheological measurements were strongly concentration dependent. At 0.5% concentration, additives exerted decreases in all the rheological properties of potato puree in the order of glycerol > alginate > lecithin > agar, while at 1% concentration, the order changed to glycerol > lecithin > alginate, whereas 1% agar behaved differently, increasing all rheological values. This study also showed that agar and alginate in addition to potato puree could be valuable and advantageous for further technological processes, such as 3D printing.

The effects of agar, alginate, butter, olive oil, and carrots on the mechanical and rheological properties of potato puree prepared by two different cooking methods (microwave heating (MP) and boiling (BP)) were investigated and interpreted in terms of starch microstructural changes. Microscopic observations revealed more aggregated and densely concentrated starch granules in MP samples. This consequently led to a significant increase (p &lt, 0.05) in mechanical and rheological properties up to five times more than BP samples. All samples exhibited shear thinning non-Newtonian behavior. Butter proved its ability to maintain stiff network formation with starch molecules forming lipid-starch complexes characterized by high retention properties and increased stability due to high thixotropic and yield stress values. The pseudo-plasticity combined with high self-supporting ability (high yield stress and mechanical values) comprised by MP samples allows them to better behave during advanced technological processes such as extrusion 3D food printing.

This study aimed to assess the effect of sous vide cooking on the total and resistant starch content, color, and shear force in three potato cultivars (Agria, Agata, and Carrera). Potato strips were also cooked by three common treatments (boiling, frying, and microwaving) to evaluate the differences between the methods. According to principal component analysis (PCA), sous vide-processed cv. Agria and Agata potato strips were grouped with boiled samples, in contrast, cv. Carrera sous vide samples were grouped with microwaved samples. Higher water losses were associated with microwaved potatoes due to the diffusion of water inside the tuber. In addition, a significant decrease in shear force was obtained after microwaving and sous vide cooking (p < 0.05) irrespective of the treatment strength. The three cultivars became less bright, and the intensity of the color decreased; however, variations in the cook value (C100, min) between treatments did not affect the lightness and hue angle. Regardless of the initial value of resistant starch and the intensity of the cooking process, all of the cultivars reached a final content of less than 5%. From our results, in-pack sterilization may be considered for application in the food industry as a technology that has a similar impact to conventional cooking treatments used on potato products.

Organoleptic qualities are an important factor in the market value of legumes, especially in developed countries. Unfortunately, the molecules that have the greatest influence on the texture of beans undergo important transformations during soaking and cooking. Moreover, the extent to which these changes are linear is unknown, making uncertain the use of raw beans in chemical screenings for sensory properties. Results of our experiments show that the amount of protein and amylose present in raw beans provides a good indicator of these substances in cooked beans (correlation coefficients between raw and cooked beans = 0.91, p ⩽ 0.001 and 0.87, p ⩽ 0.01, respectively). The Mg content in the raw seed coat also shows a strong correlation with that found in the cooked seed coat (r = 0.86, p ⩽ 0.01). The correlations found for the other traits are weaker, indicating that the evaluation of raw samples is not predictive of the findings in cooked beans.

The Ganxet bean (Phaseolus vulgaris L), highly appreciated in Catalan gastronomy, has a higher proportion of seed coat than other beans (eg White Kidney or Faba Asturiana); however, general diners and sensory tests point out a lower perception of this seed coat. The differences in chemical composition between Ganxet, White Kidney and Faba Asturiana beans, before and after cooking, were established and related to perceived sensory differences in seed coat content. Ganxet's higher absolute and percentage losses of total dietary fibre (19.5%), soluble dietary fibre (32.5%), cellulose (25.6%) and pectins (38.1%) break down the consistency of the seed coat during cooking, which would explain its low sensory perception. The high loss of cellulose during cooking could be due to its partial combination with proteins, which would aid its breakdown. © 2002 Society of Chemical Industry

In the industry of fresh-cut potatoes, controlling browning and delaying the loss of texture are important factors to obtain a high-quality product. The use of ultrasound can avoid these undesirable phenomena due to its power to inactivate enzymes by breaking the cell membranes because the cavitation activities and formation of free radicals. For this purpose, this study aimed to evaluate the effect of different times of contact of ultrasound (40 kHz, 200 W for 1, 5 and 10 min) on quality parameters (browning, firmness and total starch content) of fresh-cut potatoes during the product shelf life (12 days; 3 ± 1 C) and cell microstructure. Ultrasound was applied to asterix strips (rectangular, 10 9 10 mm). Results showed that the time of sonication and storage affected significantly to the pH of the samples. Treated samples for 5 and 10 min presented the lower values of pH. No color degradation was noticed immediately after the application of treatments (Hue and Chroma). However, a slight decrease in Hue angle of fresh-cut potatoes during storage has been observed. The use of 5 min of sonication inhibited 50 % of polyphenol oxidase (PPO) activity for the first 4 days of storage. Samples submitted to 5 and 10 min of ultrasound also had maintained more uniform firmness after frying during storage time. However, the longest time of immersion (10 min) caused damage in the potato cells.

The Ganxet bean is a landrace that is greatly appreciated in northeast Spain. For commercial purposes a pure line selection process was undertaken in this landrace. Simultaneously, the Ganxet bean was compared with standard controls for nutritional traits. Seven inbred lines, representative of the variability within the Ganxet germplasm, were studied per se and compared with bean varieties White Kidney, Navy, Faba Asturiana and Tolosa. The Ganxet germplasm was found to contain more protein, less total dietary fibre, more digestible dietary fibre, a higher proportion of seedcoat, more glucose and less starch than the controls. Study of the agronomic, commercial, nutritional and gastronomic aspects of the Ganxet inbred lines showed sufficient variability to allow two inbred lines representative of Ganxet germplasm to be chosen for commercialisation.

The chemical composition determines plant-derived foods’ sensory traits; genetic and environmental effects and their interactions determine chemical composition. Understanding the importance of each factor should help characterise foodstuffs according to the variety and place of cultivation. We studied the effects of variety (five landraces + two checks) and environment (five locations and two years) on some molecules important for beans’ ( Phaseolus vulgaris L.) sensory value. The greatest location effects were on protein and starch content and variety effects were due to combinations of traits (mainly sucrose, protein, and malic acid). The variety × location interactions detected in protein, sucrose, citric acid, and malic acid were difficult to associate to the gastronomic success of a particular variety cultivated at a particular location. Our results showed that protected designation of origin (PDO) in beans could be delimited on the basis of chemical composition, derived from the particular environmental characteristics of a region and the genetic characteristics of the varieties admitted.

Fresh-cut potato (Solanum tuberosum L.) is a product widely consumed, but the susceptibility of this tube.r to browning is a drawback and limiting factor for its shelf life. This study aimed to evaluate the predisposition of different potato cultivars for being minimally processed, the effect of citric acid in inhibiting browning and the quality of the fried potato during the product shelf-life.