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- Thermal and non-thermal Cantaloupe melon juice pasteurization: Assessment of the impact of ozone exposure on microbiological, physicochemical and bioactive characteristicsPublication . Sroy, Sengly; Fundo, Joana F.; Miller, Fátima A.; Brandão, Teresa R.S.; Silva, Cristina L. M.
- Impact of ozone processing on microbiological, physicochemical, and bioactive characteristics of refrigerated stored Cantaloupe melon juicePublication . Sroy, Sengly; Fundo, Joana F.; Miller, Fátima A.; Brandão, Teresa R. S.; Silva, Cristina L. M.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 L. innocua was previously assessed. A thermal treatment was also performed seeking comparison with ozone treatment impact. After ozone exposure, L. innocua was not detected in juice samples, while thermal pasteurization allowed a reduction of 5.2 ± 0.2 log cycles. Although ozone reduced the intrinsic microflora loads, this reduction was higher for heat‐treated samples. Vitamin C was highly retained in ozone‐treated juices (68%), when compared with the pasteurized ones (39%). After 13 days of storage, ozone allowed the retention of the most quality parameters analyzed and, therefore, it can be considered as a promising alternative to traditional pasteurization of Cantaloupe melon juice. Practical applications The actual consumers' demand for high‐quality food standards has launched research to alternative and milder nonthermal processes, which have gained increasing attention and importance in the fruit juice industries. Ideally, preservation and/or processing of foods should involve technologies that prevent undesirable microbial survival and minimize quality attributes changes and nutrient losses. Thermal treatments are conventionally used to attain such targets; however, the content and the biological activity of the most health‐related compounds are dramatically reduced. In this context, and particularly in the beverages industries, ozone has been exploited due to its potential for inactivating spoilage and pathogenic microorganisms, while being effective in overall quality retention of the products.
- UV-C radiation as an effective non-thermal process for ‘Cantaloupe’ melon juice decontaminationPublication . Mandro, Gabriela; Fundo, Joana F.; Miller, Fátima A.; Tremarin, Andréia; Brandão, Teresa R. S.; Silva, Cristina L. M.Thermal pasteurization has negative impacts on overall quality characteristics of foods. UV-C radiation has a germicidal effect and has been applied to eliminate undesirable microorganisms in food products. This technology is more effective in liquid foods, being an alternative non-thermal processing that can be applied to fruit juices.The objective of this study was to evaluate the effect of UV-C radiation on some quality characteristics and microbiological decontamination of cantaloupe melon (Cucumis meloL. var. reticulatus) juice, whichis an excellent source of antioxidant compounds, such as vitamins, phenolics and carotenoids. Cantaloupe melon juice was artificially inoculated with Alicyclobacillus acidoterrestrisspores (spoiler indicator) and Listeria innocua(non-pathogenic surrogate of L.monocytogenes), used as indicators of the UV-C treatment efficacy. The initial concentration of both microorganisms was around 107CFU/mL. Juice was exposed to UV-C radiation at an intensity of 13.44 W/m2, during 5 and 20 minutes. Some physic-chemical characteristics (pH, colour and soluble solids content), total phenolics and antioxidant capacity were evaluated before and after treatments. Exposure time affected significantly colour (very distinct alterations) and pH (slight increase from 6.3±0.1 in fresh, to 6.7±0.1 and 7.0±0.1 after 5 and 20 min of radiation; values are mean±margin of confidence interval at 95%). The remaining characteristics were not affected by the radiation and were similar to the ones observed in fresh/untreated juice. In terms of A. Acidoterrestris spores, reductions of 0.8±0.1 and 4.7±0.1log-cycles were observed after 5 and 20 minutes of radiation, respectively. For L. innocua, a reduction of 3.9±0.7 log-cycles was attained after 5 minutes and, for the highest exposure time, no cells were detected. Since UV-C was effective on microbial inactivation and was able to retain the most of quality parameters analysed, this technology can be considered as a promising alternative to traditional pasteurization of fruit juices.
- Effect of non-thermal processing on the aromatic profile of Cantaloupe melon juicePublication . Georgiev, Radoslav; Pereira, Joel; Fundo, Joana F.; Miller, Fátima A.; Brandao, Teresa R.S.; Chalova, Vesela I.; Silva, Cristina L. M.
- Thermosonication applied to kiwi juice processing: anti-listerial effect and quality retentionPublication . Striglio, Federica M.; Fundo, Joana F.; Miller, Fátima A.; Brandão, Teresa R.S.; Silva, Cristina L.M.
- Valorisation of Cantaloupe melon peel by freeze drying processPublication . Sroy, Sengly; Miller, Fátima A.; Fundo, Joana F.; Silva, Cristina L. M.; Brandão, Teresa R. S.Melon is a fruit with a high amount of waste parts, particularly peel (around 25 % of total weight). Wastes are abundant sources of bioactive compounds, considered to be health beneficial. Waste parts deserve valorisation that may be attained by developing strategies to transform them into more convenient forms that can be used as food ingredients.The objective was to transform melon peel into powder by freeze drying and assess the impact of the process on some quality characteristics (total phenolics and chlorophylls contents and antioxidant activity) and on total mesophylls and yeasts and moulds flora. Cantaloupe melon (Cucumis meloL. var. reticulatus) peel was removed and cut into small pieces. Approximately 300 g of peel was submitted to a freeze drying process (-45 ºC, 20 Pa, 96h), replicated twice. Dried samples were smashed into powder and analysed.The characteristics above mentioned and target microorganisms were evaluated before and after the freeze drying process. Initial moisture was 9.0 (dry basis; d.b.) and the water activity of dried samples was 0.060±0.010.Total phenolics content (μggallicacid/gsampled.b.) was significantly affected by the freeze drying process, decreasing 22% (2216.0±312.9 in fresh and 1720.7±227.4 after drying). Total chlorophylls content (μg/g d.b.) suffered a significant decay of 7% (923.4±13.4 in fresh and 859.2±24.1in dried samples). Antioxidant activity (μgascorbic acid/gsampled.b.) was not affected (2079.2±305.4 in fresh and 1595.6±727.4 after drying).Initial counts of mesophylls were 8.0x106cfu/mL, decreasing 0.3±0.1 log-cycles after freeze drying. Yeasts and moulds averaged 3.7x105cfu/mL in fresh peel, suffering a fall of 1.1±0.1 log-cycles after processing.Freeze dried melon peel retained antioxidant activity and a considerable amount of total chlorophylls and can be used as an innovative food ingredient with bioactive compounds. Investigation on decontamination processes is still required for maximum quality retention and safety levels of the material.
- Physicochemical and bioactive compounds of ‘Cantaloupe’ Melon: effect of ozone processing on pulp and seedsPublication . Miller, Fátima A.; Fundo, Joana F.; Silva, Cristina L. M.; Brandão, Teresa R. S.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 min) on melon seeds paste (nonedible part) and compare with the effect on pulp (edible part). Ozone treatments were evaluated in terms of physicochemical (color, pH, and soluble solids content) and nutritional profiles (total phenolics, total carotenoids, and total antioxidant capacity) of processed material. Results indicate that ozone has a different impact on the two fruit matrices, being seeds less affected by this preservation treatment.
- Physicochemical characteristics, bioactive compounds and antioxidant activity in juice, pulp, peel and seeds of Cantaloupe MelonPublication . Fundo, Joana F.; Miller, Fátima A.; Garcia, Ester; Santos, João Rodrigo; Silva, Cristina L. M.; Brandão, Teresa R. S.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 characteristics, bioactive compounds and total antioxidant activity. Juice, pulp, peel and seeds represent 42, 23, 25 and 7% of total weight, respectively. Juice and pulp presented identical profiles in terms of physicochemical characteristics, bioactive compounds and antioxidant activity. They contributed to the majority of the overall content of carotenoids (80%) and vitamin C (84%) in Cantaloupe. Peel and seeds had the highest concentrations of potassium, being seeds the richest portion (7.08 ± 0.16 mg/g). Seeds had also the significantly highest total phenolics concentration (229.13 ± 20.92 μg/g), antioxidant activity (653.67 ± 169.20 μg/g), and soluble solids content (11.79 ± 0.90 °Brix). Peel stood out by the presence of chlorophylls. Since waste parts of Cantaloupe melon represent around 32% of total weight, their valorization is a challenge and strategies to improve ways of re-using them should be developed.
- Preservation processes applied to kiwi peel as strategies to add value to fruit wastesPublication . Striglio, Federica; Miller, Fátima A.; Fundo, Joana Freitas; Silva, Cristina; Brandão, Teresa R.S.
- UV-C light processing of Cantaloupe melon juice: evaluation of the impact on microbiological, and some quality characteristics, during refrigerated storagePublication . Fundo, Joana F.; Miller, Fátima A.; Mandro, Gabriela F.; Tremarin, Andréia; Brandão, Teresa R. S.; Silva, Cristina L. M.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. monocytogenes) and Alicyclobacillus acidoterrestris spores (spoilage indicators) used as indicators of the UV-C treatment efficacy. Total mesophylls and yeasts and molds were also enumerated. Results demonstrated that 5 min of exposure allowed 3.7 ± 0.3 log10 cycles reduction of L. innocua, while for A. acidoterrestris, 20 min were required to decrease 4.7 ± 0.1 log10 cycles. At the end of refrigerated storage for 13 days, UV-C treated juices retained color, total phenolics content and antioxidant activity, and yeast and molds did not grow. Since UV-C process was effective on microbial inactivation and allowed juice quality maintenance, it can be considered as a promising alternative to thermal pasteurization.