Montserrat Pujolà

Bio: Montserrat Pujolà is an academic researcher from Polytechnic University of Catalonia. The author has contributed to research in topics: Starch & Acrylamide. The author has an hindex of 20, co-authored 42 publications receiving 1122 citations.

3D printing technology: the new era for food customization and elaboration.

Abstract: Background Digitalizing food using 3-Dimensional (3D) printing is an incipient sector that has a great potential of producing customized food with complex geometries, tailored texture and nutritional content. Yet, its application is still limited and the process utility is under the investigation of many researchers. Scope and approach The main objective of this review was to analyze and compare published articles pertaining 3D food printing to ensure how to reach compatibility between the huge varieties of food ingredients and their corresponding best printing parameters. Different from previously published reviews in the same journal by Lipton et al. (2015) and Liu et al. (2017), this review focuses in depth on optimizing extrusion based food printing which supports the widest array of food and maintains numerous shapes and textures. The benefits and limitations of 3D food printing were critically reviewed from a different perspective while providing ample mechanisms to overcome those barriers. Key findings and conclusions Four main obstacles hamper the printing process: ordinance and guidelines, food shelf life, ingredients restrictions and post processing. Unity and integrity between material properties and process parameters is the key for a best end product. For each group, specific criteria should be monitored: rheological, textural, physiochemical and sensorial properties of the material its self in accordance with the process parameters of nozzle diameter, nozzle height, printing speeds and temperature of printing. It is hoped that this paper will unlock further research on investigating a wider range of food printing ingredients and their influence on customer acceptability.

Aloe vera as an alternative to traditional edible coatings used in fresh-cut fruits: A case of study with kiwifruit slices

Abstract: In this work, a comparative study between Aloe vera, chitosan (formulated with acetic (-AC) or citric acid (-C)) and sodium alginate edible coatings was conducted to evaluate the effects on the quality and shelf life of minimally processed kiwifruit. The pH, soluble solids content, titratable acidity, ascorbic acid, color, texture properties, gas concentrations, pectin content, microbial load and sensory quality of the fruit were analyzed during 12 days at 4 ± 1 °C. Chitosan-AC and alginate based coatings act as a gas barrier, although after eight days of storage, a sharp rise in CO 2 production was detected for the alginate and chitosan-C coatings. Aloe vera coating maintained the firmness of the fruit, prevented the ascorbic acid losses and yellowing due to ripening. Aloe vera and chitosan-AC reduced microbial proliferation; however chitosan-AC coated slices were not accepted by the sensory panelists. In contrast, fruit treated with an alginate based coating had higher microorganism counts than the control samples. The sensory panel preferred the kiwifruit slices treated with Aloe vera or chitosan-C coatings compared to the other coatings. Our study indicates that Aloe vera was the best coating to both extend the postharvest shelf life and maintain the sensory properties of the product trough the storage period.

Short-term assay of soil urease activity using colorimetric determination of ammonium

Abstract: A rapid assay for soil urease in the absence of bacteriostatic agents has been developed. The method comprises incubation of soil with an aqueous or buffered urea solution, extraction of ammonium with 1 N KCl and 0.01 NHCl and colorimetric NH4 + determination by a modified indophenol reaction. The method is characterized by high sensitivity and stability of the coloured complex formed. Measurements obtained by this method showed that no change in urease activity occurred when field-moist samples of soils were stored at −20°C for as long as 5 months. Air-drying of field-moist soil samples may lead to an increase in urease activity.

Effects of anaerobic digestion on digestate nutrient availability and crop growth: A review

Abstract: Anaerobic digestion (AD) for biogas production leads to several changes in the composition of the resulting digestates compared to the original feedstock (ammonia content, pH, carbon to nitrogen ratio, etc.), which are relevant for the plant availability of macro- and micronutrients after field application. Increased NH4+-N content in digested slurries compared to undigested slurries does not guarantee improved uptake efficiency of slurry nitrogen and increased savings in fertilizer nitrogen. AD of crop residues and cover crops leads to an increase in the total amounts of mobile organic manures within the farming system, resulting in a higher nitrogen use efficiency and an increased scope for target-oriented nitrogen application in time and space, when needed by the crop, as an alternative to the site-bound soil incorporation as green manures. AD of dairy manure appears to reduce the fraction of immediate plant available phosphorus and micronutrients. This does, however, not affect short-term crop availability under field conditions. More studies are needed to improve current knowledge on sulfur losses during AD and fertilizer value of digestates.

Soil Enzyme Activities as Indicators of Soil Quality

Abstract: With the increasing pressure to produce more food, fiber, and fuel to meet world demands on a limited land area, there is an unprecedented need to address global concerns about soil degradation. Understanding the underlying biological processes in tandem with identification of early warning indicators of ecosystem stress is needed to provide strategies and approaches for land resource managers and policymakers to promote long-term ecosystem sustainability. Biological and biochemically mediated processes in soils are fundamental to terrestrial ecosystem function. Ultimately, all members of the food web are dependent on the soil as a source of nutrients, and for degradation and cycling of complex organic compounds. Primary decomposers of organic matter provide energy that supports the activities of organisms from a number of trophic levels in soils. Historically, chemical and physical properties have been used as crude measures of soil productivity. Most notably, determination of soil organic matter has been related to general soil tilth. Soil organic matter changes very slowly, and therefore, many years may be required to measure changes resulting from perturbations. However, there is growing evidence that soil biological parameters may hold potential as early and sensitive indicators of soil ecological stress or restoration (Dick, 1992; Dick & Tabatabai, 1992). In Chapter 5 (this book) information is provided on soil quality in relation to soil microorganisms. In this chapter, soil enzyme activities will be discussed as a potential biochemical/biological indicator of soil quality.