Cristina L M Silva

• PhD
• Professor (Associate) at Universidade Católica Portuguesa

Due to the increasing consumer demand for healthy, beneficial foods, natural fruit juices have gained popularity for their rich nutritional value and appealing flavor. However, traditional thermal processing can compromise these quality attributes. This study investigates using pulsed thermosonication, a novel mild thermal processing method, on Lis...

Avocado production is mostly confined to tropical and subtropical regions, leading to lengthy distribution channels that, coupled with their unpredictable post-harvest behavior, render avocados susceptible to significant loss and waste. To enhance the monitoring of ‘Hass’ avocado ripening, a data-driven tool was developed using a deep learning appr...

This study explores the potential of thermosonication as an alternative to traditional heat treatments, such as pasteurization, in the processing of fruit juices. Conventional methods often lead to undesirable quality changes in fruit juices, whereas thermosonication offers promising results regarding microbial inactivation and quality preservation...

Recent years have seen a remarkable growth trend in avocado consumption, with projections that its exports will overpass those of pineapple by 2030, becoming the second most traded tropical fruit. When paired with their high unit value, this growth could make the avocado one of the most important fruit commodities of the next decades. As the produc...

Most Food Science and Technology curricula are very technical driven, preparing the students to meet the industry demands or embrace a researching career. Although this model accomplishes its purpose when the students follow that path, it also understimulates their entrepreneurial creativity, potentially adding to the overall inertia of starting ne...

The 2030 Sustainable Development Agenda calls for all social actors to contribute to significant societal and environmental issues [...]

The peels of many fruits are rich sources of nutrients, although they are not commonly consumed. If they are properly decontaminated, they can be used as healthy food ingredients reducing food waste. The objective was to apply thermosonication processes to kiwi peel and evaluate the impact on Listeria innocua survival (a non-pathogenic surrogate of...

Melon peel is recognized as a source of healthy nutrients and oxidant compounds. Being considered a non-edible part with no profit value, large amounts of melon rinds are discharged by fruit industries. Innovative food ingredients with potential health benefits may arise if these parts were conveniently transformed. The objective was to freeze-dry...

Nowadays, consumers demand high-quality and fresh-like food products. In the fruit juices industry, the applied processes to guarantee safety and increase shelf life often negatively impact final product quality. Although thermal treatments are the most frequently applied processes to preserve fruit juices, heating may induce undesirable changes in...

Fruit waste parts, particularly peel, are abundant sources of bioactive compounds. To be included in the formulation of value-added foods, peel needs to be transformed and subjected to a preservation process. Therefore, this study seeks to assess the effect of ozone on the quality and antilisterial indicators of cantaloupe melon peel paste, aiming...

In order to improve the overall quality of frozen carrots (Daucus carota L.), the degradation kinetics of several attributes were quantified during frozen storage under isothermal and nonisothermal conditions. The experimental results showed that the analyzed quality parameters were significantly affected by both tested frozen regimes. For both sto...

The production of rapeseed oil leads to generation of large quantities of rapeseed meal as a by-product. To increase the applicability of the rapeseed meal in feed and food industries, the content of antinutrient compounds is often reduced by treatment with ethanol. The aim of the study was to evaluate the influence of ethanol pre-treatment of the...

The solubility of plant protein isolates is a key determinant of their potential application. Two protein isolates (PI) from ethanol-treated industrial rapeseed meal, PI10.5–2.5 and PI2.5–8.5, were prepared by sequential isoelectric precipitation of alkali-extracted proteins (pH 12) starting from pH 10.5 to 2.5 or from pH 2.5 to 8.5, respectively....

In recent years, solar cooking has become increasingly explored due to the importance of energy savings, sustainability and reduction of fossil fuel consumption. However, while several authors have mainly focused on analysis and modeling of solar cookers thermal performance, food science research on the impact of this cooking method on food quality...

Broccoli (Brassica oleracea L. ssp. Italica) is recognized worldwide as one of the most nutritious vegetables and a good source of bioactive compounds, including antioxidants, phenolics and vitamins. Epidemiological studies have proven a positive correlation between broccoli consumption and health benefits such as the reduction of cancer risk. Ther...

Tomatoes are a popular and rich fruit due to their nutritional and bioactive composition as vitamins, antioxidants, and phenolics contributing to the promotion of consumer health. For this reason, emerging postharvest technologies need to be evaluated to achieve the maintenance of sensorial and quality-related characteristics, like color and textur...

The objective of this study was to evaluate the impact of ozone treatment on microbiological decontamination (intrinsic microflora and inoculated Listeria innocua) and some physicochemical characteristics and bioactive compounds of Cantaloupe melon juice, also during refrigerated storage. To determine adequate ozone exposure, the survival curve of...

Two biopreservation approaches for fresh lettuce, rocket salad, parsley and spinach were studied. The potential of Pediococcus pentosaceus DT016, as a protective culture, to suppress Listeria monocytogenes in vegetables during storage was evaluated. The pathogen numbers in the vegetables inoculated with P. pentosaceus DT016 were significantly (p<0...

Rapeseed meal is produced in large quantities as a by-product of vegetable oil production. To enhance the utility and profitability of the rapeseed meal, it was treated with ethanol and used for concomitant preparation of two protein-rich ingredients, namely protein isolate (PI) and acid soluble protein (ASP). Their functional properties were evalu...

Mathematical modelling plays an important role in food engineering having various mathematical models tailored for different food topics. However, mathematical models are followed by limited information on their application in food companies. This paper aims to discuss the extent and the conditions surrounding the usage of mathematical models in th...

andreiacosta94@icloud.com Freezing vegetables requires pre-treatments to reduce microbial load and destroy enzymes that impair the frozen product quality. So far blanching has been the most effective pre-treatment, preferred by the food industry, despite its severity: heating up to temperatures close to 100 °C for 1–3 min causes sensory and texture...

A protein isolate (ERPI) was prepared from ethanol-treated rapeseed meal and used as a stabilizing agent in sunflower and rapeseed oil-in-water emulsions. The aim of the current study was to explore the influence of protein and oil concentrations on initial stability of sunflower and rapeseed oil-in-water emulsions by evaluating Gibbs free energy (...

UV-C light is a non-thermal technology with potential application in food industries. The objective was to assess UV-C radiation effect (13.44 W/m²) on microbiological decontamination and some quality characteristics of Cantaloupe melon juice, during refrigerated storage. Juice was inoculated with Listeria innocua (non-pathogenic surrogate of L. mo...

BACKGROUND Wine colour is an important quality parameter, being the first sensorial attribute evaluated during wine tasting. The perception of wine colour can be different depending on many factors, including the depth of the sample under observation. The main objectives of the present study were to measure the colour of Port wines using CIE L*, a*...

A spore-forming bacterium, Alicyclobacillus acidoterrestris, is often responsible for fruit juices quality degradation. The objective was to study the influence of ultrasounds and combinations with temperature (thermosonication) on A. acidoterrestris spores inactivation in apple juices. Commercially available juice was artificially inoculated with...

Ozone is used in grains to guarantee mycotoxin degradation, microbial inactivation, and insect disinfestation. However, its oxidizing properties can promote changes in the grain constituents, affecting both product properties and process behavior. Even so, the effect of ozone processing on quality properties of grains and their process, was rarely...

The use of the rapeseed meal as a source for preparation of protein-rich ingredients for the food industry is an alternative to the current limited application as a feed additive. The aim of this study was to evaluate foaming properties of an acid-soluble protein-rich ingredient (ASP) obtained from industrial rapeseed meal as a co-product of a prot...

The knowledge produced by students from PhD Programs in agro-food science and technology areas when assessed by companies can result in technology transfer processes, being in this way a source for innovation. Therefore, creating an environment that promotes the interaction between university and business, as well as promoting the entrepreneurial s...

Ozone treatment is a non-thermal technology with promising applications in food processing. The objective of this study was to evaluate the effect of gaseous ozone at a concentration of 7.0 ± 2.4 g/L for 30 and 60 min of exposure, on some physicochemical characteristics (soluble solids content, pH, titratable acidity and color), bioactive compounds...

Although it is known that fruit products are rich sources of natural bioactive compounds, information on the nutritional value of their waste parts is scarce. The objective was to characterize the edible (juice and pulp) and waste (peel and seeds) parts of Cantaloupe melon (Cucumis melon L. var. reticulatus) in terms of some physicochemical charact...

Melon seeds are an important source of bioactive compounds, which are considered to be health beneficial. Therefore, the objective of this work was to assess the impact of gaseous ozone treatments (30 and 60 minutes) on melon seeds paste (non-edible part), and compare with the effect on pulp (edible part). Ozone treatments were evaluated in terms o...

Microbial inactivation often follows a sigmoidal kinetic behaviour, with an initial lag phase, followed by a maximum inactivation rate period and tending to a final asymptotic value. Mathematically, such tendencies may be described by using primary kinetic models (Gompertz based model is one example) that describe microbial survival throughout proc...

Evaluation of the effect of bean processing with ozone on its phenolic compounds and antioxidant capacity, as well as its impact on the physical properties and inactivation of Listeria innocua.

Many minimally processed foods depend on a combination of inhibitory factors to reduce the hazard of foodborne illness. Therefore, inactivation of Listeria innocua was studied according to a 24 factorial experiment designed to draw conclusions about temperature (52.5 °C and 65.0 °C), pH (4.5 and 7.5), water activity (aw=0.95 and 0.99) and solute ty...

Many minimally processed foods depend on a combination of inhibitory factors to reduce the hazard of foodborne illness. Therefore, inactivation of Listeria innocua was studied according to a 2⁴ factorial experiment designed to draw conclusions about temperature (52.5 °C and 65.0 °C), pH (4.5 and 7.5), water activity (aw=0.95 and 0.99) and solute ty...

This chapter discusses the simulation process of food solar drying, presenting the basic issues of mass and heat transfer under time-varying conditions. Food drying embraces several phenomena, and scientists do not completely understand its underlying mechanisms. However, mathematical simulation and modelling provide comprehensions to improve the k...

The purpose of this study was to evaluate the drying characteristics and the effects of convective drying temperature on quality attrib0utes of watercress, without any pretreatment. Drying temperatures of 40, 55, and 70 °C resulted in drying times of 230, 119, and 92 min, respectively. The nutritional parameters were negatively correlated with the...

Byssochlamys fulva is an ascospore producer fungus known to be heat resistant and commonly found in fruit juices. This work aims at studying the influence of soluble solid content and storage temperature on the growth of B. fulva in apple juices. Agar-added apple juices, adjusted to different levels of soluble solids (12, 20, 25, 35, 45, 55, 70 °Bx...

Protein-rich products, prepared from industrial rapeseed meal, have the potential for versatile applications in the food, feed, and nutraceutical industries. The aim of study was to characterize the biochemical composition of two protein-rich products obtained from industrially produced rapeseed meal. Protein isolate (PI) and acid soluble protein (...

This work evaluated the effect of the air-drying temperature and vacuum packaging on quality and nutritional compounds of dehydrated galega kale, previously steam blanched, during 5 months of storage. When compared with the vacuum packaged kale, the packaging without vacuum yielded improved nutritional features, in general. This approach combined w...

It is well known that temperature is the key factor controlling the microbial survival/inactivation. However, the interactive effects of further stressing environmental conditions may influence microbial behaviour. The objective of this work was to include, in the inactivation model, temperature, pH and aw effects using a black box polynomial model...

This work focuses on the use of the Gompertz-inspired model to predict the thermal inactivation behaviour of microorganisms obtained in solid food products, validated for isothermal and non-isothermal conditions. Experiments were carried out in parsley, artificially inoculated with Listeria innocua. For the isothermal conditions tested, the predict...

Alicyclobacillus acidoterrestris is a spore-forming bacterium, which is responsible for quality degradation of fruit juices. Non-thermal treatments, such as ultraviolet-C radiation (UV-C) and ultrasound (US), are promising methods for microbial inactivation. The main objective was to study the influence of UV-C, ultrasound and combinations of both...

Ultraviolet-C radiation (UV-C) is widely used as an alternative strategy to control microorganism in food products. Alicyclobacillus acidoterrestris is a thermo-acidophilic, non-pathogenic and spore-forming bacterium, able to grow at low pH and high temperatures. It is a concern, particularly in apple juice thermal pasteurization, because it is res...

Fresh-cut fruit is an important segment in fruit market due to the increasing demand for healthy/convenient foods. However, processing promotes a decrease in fruits stability with faster physiological and microbiological deteriorations. Food stability is strongly attributed to its molecular dynamics and “water availability”. Understanding changes i...

Previously optimised postharvest treatments were compared to conventional chlorinated water treatment in terms of their effects on the overall quality of tomato (‘Zinac’) during storage at 10 °C. The treatments in question were water heat treatment (WHT = 40 °C, 30 min), ultrasounds (US = 45 kHz, 80 %, 30 min), thermosonication (TS = 40 °C, 30 min,...

The objective of this work was to evaluate the effect of six pretreatments on quality and nutritional contents of sliced Galega kale submitted to convective drying. Among all treatments, steam blanching was the most favourable, allowing improvements in retention of vitamin C, total antioxidant capacity and chlorophylls in comparison to the absence...

The main goal of this chapter is to evaluate the potential functional properties of nuts and dried fruits cultivated in Portugal, contributing for the valorization of the national species, increasing of local products consumption, and local environment and socio-economic sustainability. This work contributes also to value a Mediterranean diet, incl...

Natural fruit juices are difficult to transform into powder because they are rich in sugars and acids with low glass transition temperatures, resulting in a sticky behaviour during spray drying. The present research work aimed to test the prebiotics maltodextrin and arabic gum as drying agents in order to be able to produce dehydrated powder from p...

Editorial: The general aims of the ISEKI_Food conference series are to contribute to the creation of an ‘‘open’’ international forum for researchers, education scientists, technologists and industry representatives as well as food consumers, to promote constructive dialogue and collaboration on topics relevant to Food Science and Technology, Indust...

Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.  Authors are able to enter into separate, additional contractual...

The qualifications of Food Science and Technology/Engineering (FST/E) professionals were examined by a web-based survey conducted in 15 countries (14 EU and Turkey). The analysis of the responses showed that 65% of the respondents had a higher education (HE) degree (BSc 29%, MSc 28%, and PhD 8%), and 20% carried out extracurricular training before...

The aim of this study was to develop fruit powders (apple, banana and strawberry) enriched with a probiotic strain (Lactobacillus plantarum 299v). Two methodologies were proposed: (i) drying (by convection) of the fruit withprobiotic culture incorporated or (ii) drying (by convection) of the fruit and addition of spray-dried probiotic culture. In t...

The effect of UV-C treatments (0.32, 0.97, 2.56, 4.16 and 4.83 kJ.m(-2) at 254 nm) on the physical-chemical properties [colour, texture, total phenolic content (TPC), weight loss (WL)], and mesophylic counts of whole tomato, was evaluated during 15 days at 10 °C. During storage, the Ctr samples acquired faster red colour than all UV-C samples (high...

Drying has been applied to vegetables in order to preserve, store and transport these food products. However, drying implies not only physical changes, easily detectable by the consumer through visual assessment, but also chemical modifications. These are not always visible, but are responsible for alterations in colour, flavour and nutritional val...

The objective of this work was to evaluate the drying characteristics and the effect of drying temperature on the quality characteristics of Galega kale without any pretreatment. Drying times of 330, 162, 78 and 51min provided minimal moisture contents, using temperatures of 35, 50, 70 and 85C, respectively. The L* and a* values diminished and b* i...

In this work physical-chemical properties of chitosan/ glycerol film forming solutions (FFS) and the resulting films were analysed. Solutions were prepared using different concentrations of plasticising agent (glycerol) and chitosan. Films were produced by solvent casting and equilibrated in a controlled atmosphere. FFS water activity and rheologic...

Molecular mobility is a fundamental parameter which reflects the dynamic properties of food components and contributes to food degradation reactions comprehension. Fresh-cut fruits have become an important food market segment. However, processing of fruits promotes faster its physiological deterioration, biochemical changes and microbial degradatio...

Foods are partially crystalline partially amorphous systems. Edible films are considered good models for food systems due to their interesting physical properties, quite straightforward matrices, and easy reproduction. Chitosan is a semicrystalline biopolymer, biocompatible, biodegradable, with antimicrobial activity and filmogenic properties, and...

Physical properties and stability are critical for delivering safe and healthy food to the consumers and thus is a theme that attracts food scientists for a long time. Recently, literature suggests that stability can be fully grasped only if food molecular dynamics and structure are taken into consideration, i.e. an appropriate understanding of the...

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Two different pre-treatments were applied to grapes prior to drying in a mixed mode solar dryer. Grapes were blanched in water and in a 0.1% sunflower oil water emulsion, both at 99oC and for approximately 15 seconds. Several models were tested to fit the experimental data of drying curves but the normalized Newton model gave the best fit results....

A shelf-life study on cupuaçu nectar (Theobroma grandiflorum) was carried out in two parts. Part I studied the microbial stability of the regular nectar (batch R) and the same nectar fortified with synthetic ascorbic acid (AA) (batch F), pasteurized at 90 °C for 3 min and hot filled in glass bottles. Total Plate Count (TPC), yeast and molds as well...

A shelf-life study on cupuaçu nectar (Theobroma grandiflorum) was carried out in two parts. Part I studied the microbial stability of the regular nectar (batch R) and the same nectar fortified with synthetic ascorbic acid (AA) (batch F), pasteurized at 90 °C for 3 min and hot filled in glass bottles. Total Plate Count (TPC), yeast and molds as well...

Ozone has been recognized as a promising food processing agent, which is gaining interest in the food industry due to its oxidant properties. In order to generate commercial levels of ozone, the corona discharge method is generally used. However, there are other less mainstream methods of ozone generation, such as electrochemical and radiochemical...

European Higher Education, learning outcomes and competences have been used sometimes with different meanings and sometimes with the same meaning. But both terms have been more commonly used to refer to knowledge, understanding and abilities a student must demonstrate at the end of a learning experience. Their use is a consequence of the paradigm s...

Two different pre-treatments were applied to grapes prior to drying in a mixed mode solar dryer. Grapes were blanched in water and in a 0.1% sunflower oil water emulsion, both at 99oC and for approximately 15 seconds. Several models were tested to fit the experimental data of drying curves but the normalized Newton model gave the best fit results....

The microbiological safety of fresh produce is a significant concern of consumers and industry. After applying at an inoculated level (6–7 log CFU/mL) of Listeria monocytogenes on Iceberg lettuce, the antilisterial properties of balsamic vinegar from Modena, white wine vinegar and acetic acid solutions were investigated. Different proportions of th...

This study evaluated the effect of water heat treatment (WHT, immersion in a water bath at 40C – 30 min) application in alternative to the conventional decontamination treatment of chlorinated water (150 ppm at 5C, pH 6.5 during 2 min) on tomato (cv. Zinac) at two maturity stages (turning and pink).Physiochemical attributes, enzymatic activities an...

e-learning refers to the use of technology in learning and education. There are several aspects to describe the intellectual and technical development of e-learning, and these aspects can be categorized into discrete areas. One of the main objectives of the working packages on `Teaching Materials & Methods` in ISEKI-Food projects focused on prepar...

Fresh tomato (Solanum lycopersicum) is one of the most consumed fruits and the preservation of itsquality and shelf-life extension is a continuous challenge. An understanding of fruit deteriorationfactors allows the investigation of new approaches to reach this objective. Fruit preservationis achieved by destroying enzymes and micro-organisms, and...

Strawberry is an attractive fruit, with potential benefits to human health, due to its excellent sources of natural antioxidants, anthocyanins, flavonoids, phenolic acids, as well as nutritive compounds such as minerals, vitamins and dietary fibers. However, strawberries are extremely perishable as a consequence of tenderness and susceptibility to...

Vegetables play a particularly important role in human diet and their stabilization after harvesting and during sub-sequent storage is critical. Among several long-term preservation processes, freezing is widely recognized as a proven and efficient method for vegetables. Most vegetables require a short heat treatment (blanching) prior to freezing t...

Fresh tomato (Solanum lycopersicum) is one of the most consumed fruits and the preservation of its quality and shelf-life extension is a continuous challenge. An understanding of fruit deterioration factors allows the investigation of new approaches to reach this objective. Fruit preservation is achieved by destroying enzymes and micro-organisms, a...

Consumers expect that food products will be safe and convenient to use and still have all the qualities of a fresh product. Foods often undergo processing, which has three major aims: to make food safe while providing products with the highest quality attributes, to transform food into forms that are more convenient or more appealing, and to extend...

The development and application of efficient methods for the preservation of food products have always been industrial concerns. The search for new technologies that assure safety and quality of the products is an ever-growing challenge. In this context, ozone has emerged, presenting a set of characteristics that makes it highly suitable for fruits...