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- Quality Index Method for fish quality control: Understanding the applications, the appointed limits and the upcoming trendsPublication . Freitas, Jorge; Vaz-Pires, Paulo; Câmara, José S.Background: The Quality Index Method (QIM) is a widely used approach for fish sensory grading, based on a structured scaling for freshness measurements, providing information concerning the fish freshness status, as a prediction of the remaining shelf-life for specific species or products. However, its tendency to be used in an oversimplified way and other common misapplications could lead to discredit of a methodology with great potential. Scope and approach: Review the principles of QIM methodology, discussing its concept, applications, and un derstand their limits, as a useful strategy to propose improvements, reinforce its predictive power and consequent acceptability. Key findings and conclusions: QIM methodology is based on a compromise between the number of fish samples necessary and the number of attributes, with sensory relevance in fish spoilage, that allows verifying if quality requirements are fulfilled. However, the assumptions inherent to the method, undermine the reliability of the shelf-life predictions. Determination of the variability associated with assessors, product, and correct structure of datasets for statistical analysis, will improve the predictive power of the method. However, it could lead to an increase in the method complexity that would drive it away from the industry’s needs for fast and easily implemented methods.
- Freshness assessment and shelf-life prediction for Seriola dumerili from aquaculture based on the quality index methodPublication . Freitas, Jorge; Vaz-Pires, Paulo; Câmara, José S.Fish and fish-based products are easily perishable foods due to different factors, including fragile organization, abundant endo-enzymes, psychrophilic bacteria, and impact of pre-harvest operations, that contribute to reducing its value. Therefore, a timely effective method for fish freshness and shelf-life evaluation is important. In this context, this study aimed to develop a sensory scheme based on the Quality Index Method (QIM) (sensory table and point system) for freshness monitorization and shelf-life prediction for Seriola dumerili from aquaculture in Madeira Island. Evaluation of appearance, texture, eyes, and gills was performed during 20 days of storage on ice (0 ± 1 ◦C). The shelf-life prediction was supported by the analysis of microorganisms (total viable colonies, TVC, counts), texture (Torrymeter), and production of trimethylamine (TMA), evaluated by HS-SPME–GC–MS and validated according to Association of Official Analytical Chemists AOAC guidelines. The result is a QIM scheme with 25 demerit points, where zero indicates total freshness. From the integration of sensory analysis, microbial growth at the time of rejection (TVC, 108 cfu/cm2 and H2S producers, 107 cfu/cm2 ), texture (Torrymeter value < 8), and TMA analyses (>12.5 mg/100 g), shelf-life was estimated as 12 days (±0.5 days). The obtained results show the high-throughput potential of the developed method for fish freshness assessment and shelf-life prediction. This QIM scheme is a secure way to measure quality and provide users with a reliable standardized fish freshness measure.
- Establishment of authenticity and typicality of sugarcane honey based on volatile profile and multivariate analysisPublication . Silva, Pedro; Freitas, Jorge; Silva, Catarina L.; Perestrelo, Rosa; Nunes, Fernando M.; Câmara, José S.Sugarcane honey (SCH) is a black syrup produced in Madeira Island widely known for their excellent quality being used in traditional pastry and confectionery. However, its notoriety has been affected by circumstances in which some producers do not guaranty the product quality. The purpose of this study was to establish, for the first time, the volatomic profile of SCH produced by certified and non-certified producers in order to define their authenticity and typicality as useful platform to ensure SCH safety, protect consumer interests and fight the continuous problems of food fraud and adulteration. Solid-phase microextraction in headspace mode (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was applied as high throughput approach for extraction, separation and identification of SCH volatile compounds. The extraction technique was optimized for nature of stationary phase, extraction temperature, extraction time, and validated according with IUPAC and AOAC guidelines. Different volatomic fingerprints for SCH from certified and non-certified producers were recognized, being identified up to 87 volatile organic compounds (VOCs) belonging to distinct chemical classes, mainly aldehydes, alcohols, ketones and furans. One-way ANOVA analysis showed the existence of 18 VOCs with statistically significant differences between volatile profiles from certified and non-certified producers. Principal component analysis (PCA) and linear discriminant analysis (LDA) differentiate and discriminate the samples from both type of producers. According to the obtained results, the followed strategy revealed an effective way to establish the authenticity and typicality of SCH, providing useful information to producers that might therefore be used to improve the SCH quality and a powerful platform to promote a European certification application.
- From aquaculture production to consumption: freshness, safety, traceability and authentication, the four pillars of qualityPublication . Freitas, Jorge; Vaz-Pires, Paulo; Câmara, José S.Farmed aquatic products are among the most widely traded commodities and one of the sectors with the fastest growth in the last years. However, aquaculture is still affected by negative connotations in comparison with other agroindustry sectors. Markets, consumer preferences and concerns about food safety and sustainability are influencing the growth of the sector and are forcing the implementation of quality management systems. Modern management systems help to minimize the environmental impacts and the distribution of unsafe or poor-quality products, thereby reducing the potential for bad image, liability and recalls. This article presents a compre hensive overview of the status, relevance, and impact of the quality management systems in the development of marine aquaculture, with the focus on four of the most important criteria associated with these systems: freshness, safety, traceability, and authenticity.
- A fast and environment-friendly MEPS PEP /UHPLC-PDA methodology to assess 3-hydroxy-4,5-dimethyl-2(5H)-furanone in fortified winesPublication . Freitas, Jorge; Perestrelo, Rosa; Cassaca, Rubina; Castillo, Mariangie; Santos, Mariana; Pereira, Jorge; Câmara, José S.Sotolon is widely associated with the quality of fortified aged wines, and has also been linked to premature oxidative aging (premox). Here we developed a single, fast and environmental-friendly microextraction by packed sorbent ultra-high pressure liquid chromatography analysis (MEPS/UHPLC-PDA) for sotolon quantification in different wines. The best extraction conditions (loading three times 250μL samples through the MEPSPEP sorbent and elution with 100μL of 50% MeOH) were combined with a fast UHPLC separation (5min separation using acidified 10% MeOH isocratic flow in a CORTECS C18 column) to allow unparalleled minimum sample and solvents volumes usage. The validated methodology showed good linearity (r(2)>0.993) and precision (<5.6%); high recovery (>81%) and detection limits (0.45-2.51μg/L) far below sotolon odor threshold for any type of wine. The methodology was successfully applied to selected white table and Madeira wines, encompassing therefore a wide range of alcohol and sugar contents. Furthermore, as far we may know, this is the first time a single methodology can be used to assess both wine aging or premox according to the type of wine.
- A systematic AQbD approach for optimization of the most influential experimental parameters on analysis of fish spoilage-related volatile aminesPublication . Freitas, Jorge; Silva, Pedro; Vaz-Pires, Paulo; Câmara, José S.The volatile amines trimethylamine (TMA) and dimethylamine (DMA) could be used as important spoilage indices for seafood products, assisting in the determination of the rejection period. In the present study, a systematic analytical duality-by-design (AQbD) approach was used as a powerful strategy to optimize the most important experimental parameters of headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) conditions for the quantification of TMA and DMA in Sparus aurata. This optimization enabled the selection of the best points in the method operable design region for HS-SPME extraction (30 min; 35 ◦C; NaOH 15 M and NaCl 35%, w/v) and GC-MS analysis (80 ◦C; gradient 50 ◦C/min; flow rate 1 mL/min and splitless mode). The rejection day, estimated through the TMA concentration (>12 mg/100 g, at days 9–10), was compared with sensory (quality index method: day 7–8), physical (Torrymeter: day 8–9), and microbial (day 9–10) analysis, corroborating the suitability of the proposed approach for estimating the period for which they will retain an acceptable level of eating quality from a safety and sensory perspective.
- Effect of processing and storage on the volatile profile of sugarcane honey: A four-year studyPublication . Silva, Pedro; Freitas, Jorge; Nunes, Fernando M.; Câmara, José S.Sugarcane honey (SCH) is a syrup from Madeira Island recognized by its unique and excellent aroma, associated to volatile organic compounds (VOCs) generated during the well-defined five stages of its traditional making process. The establishment of volatile profile throughout all SCH-making stages during four years, allowed the evaluation of the influence of each stage in the typical characterisitcs of SCH. One hundred eighthy seven VOCs were identified, being associated to several origins and formation pathways. VOCs formed during stage 1 and 2 were originate from raw material, and its oxidation (i.e. enzymatic browning) and thermal degradation (i.e. lipid oxidation, Maillard reactions, Strecker degradation). In stage 3 and 4, the caramelization and melanoidin degradation also occurred, while in stage 5, the thermal degradation continues, followed by microbial activity. Chemometric analysis allowed to identify 35 VOCs as potential markers for processing control by the producers and as guarantee of the typicality and authenticity of SCH. Based on the obtained results, we propose for the first time an innovative schematic diagram explaining the potential reactions and pathways for VOCs formation during the different steps of the SCH production.
- Sustainable Agricultural Systems for Fruit Orchards: The Influence of Plant Growth Promoting Bacteria on the Soil Biodiversity and Nutrient ManagementPublication . Freitas, Jorge; Silva, PedroAwareness towards the loss of soil quality as well as consumer perception about the environmental impact of agricultural activity have stimulated research and government activity toward the implementation of a sustainable agricultural system. The European Commission, in the next funding program, established specific objectives to promote the conversion towards a more environmentally sustainable agricultural system through its Green Deal Strategy. The demand for ecologically and sustainably cultivated fruits increases every year; however, suppressing such de mand is necessary to improve the production performance of orchards. The sustainable management of orchard production requires combined knowledge from different fields. The key challenge is to design orchard systems that can integrate sustainable practices, nutrient cycle knowledge and promotion of soil biodiversity. Therefore, this review compiles works that address the challenges in the implementation of a sustainable agriculture system based on Plant Growth-Promoting Bac teria (PGPB) and their impact on soil biodiversity as well as that of nutrient management on the development of fruit orchards.
- Emerging contaminants in seafront zones. Environmental impact and analytical approachesPublication . Câmara, José S.; Montesdeoca-Esponda, Sarah; Freitas, Jorge; Guedes-Alonso, Rayco; Sosa-Ferrera, Zoraida; Perestrelo, RosaSome chemical substances have the potential to enter the coastal and marine environment and cause adverse effects on ecosystems, biodiversity and human health. For a large majority of them, their fate and effects are poorly understood as well as their use still unregulated. Finding effective and sustainable strategies for the identification of these emerging and/or anthropogenic contaminants that might cause polluting effects in marine environments to mitigate their adverse effects, is of utmost importance and a great challenge for managers, regulators and researchers. In this review we will evaluate the impact of emerging contaminants (ECs) on marine coastal zones namely in their ecosystems and biodiversity, highlighting the potential risks of organic pollutants, pharmaceuticals and personal care products. Emerging microextraction techniques and high-resolution analytical platforms used in isolation, identification and quantification of ECs will be also reviewed.
- Chemical Differentiation of Sugarcane Cultivars Based on Volatile Profile and Chemometric AnalysisPublication . Silva, Pedro; Freitas, Jorge; Nunes, Fernando M.; Câmara, José S.Sugarcane (SC) is a perennial grass widely cultivated in tropical and subtropical regions. However, its cultivation in Europe is residual, where Madeira Island, Portugal, is the only region where SC continues to be extensively cultivated. For the first time, the volatile profiles of regional cultivars were established by solid-phase microextraction combined with gas chromatography− mass spectrometry. Different volatile profiles for each cultivar were recognized, identifying 260 volatile organic compounds belonging to 15 chemical classes, such as aldehydes, alcohols, ketones, hydrocarbons, esters, and terpenes. Chemometric analysis procedure, namely, one-way ANOVA with Tukey’s test, principal component analysis, partial least-square analysis, linear discriminant analysis, and hierarchical clustering analysis, allowed the differentiation between all regional cultivars. This study represents an important contribution for the maintenance of biodiversity and subsistence of the SC industry in Europe. Furthermore, it is also a valuable contribution to establish the typicality of traditional SC-based products, such as SC honey.