Thermosonication applied to kiwi juice processing: anti-listerial effect and quality retention

info:eu-repo/semantics/acceptedVersio

Thermal and non-thermal Cantaloupe melon juice pasteurization: Assessment of the impact of ozone exposure on microbiological, physicochemical and bioactive characteristics

info:eu-repo/semantics/publishedVersio

Freeze and freeze drying applied as preservation processes of melon peel

info:eu-repo/semantics/submittedVersio

Impact of UV-C radiation on melon peel

info:eu-repo/semantics/publishedVersio

Impact of ozone processing on microbiological, physicochemical, and bioactive characteristics of refrigerated stored Cantaloupe melon juice

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.info:eu-repo/semantics/publishedVersio

Effect of gaseous ozone process on cantaloupe melon peel: assessment of quality and antilisterial indicators

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 at obtaining a product with the potential to be used as a food additive. Ozone was bubbled during 30 and 60 min, and some physicochemical characteristics (soluble solids content, pH and colour), bioactive compounds (total phenolics, chlorophylls and vitamin C) and antioxidant activity were analysed. Peel was also inoculated with Listeria innocua, used as a treatment efficiency indicator. The results indicated that, although ozone negatively affected antioxidant activity, it positively influenced all bioactive compounds analysed. An L. innocua reduction of 1.2 log cycle was achieved after ozone exposure. Ozone should be exploited as a promising technology to assure the quality/safety of cantaloupe melon peel. Indeed, if melon peel is conveniently converted into a suitable form that can be used as a food ingredient, this will promote the valorisation of waste materials with the consequent reduction of industrial by-products and new perspectives for market opportunities.info:eu-repo/semantics/publishedVersio

Valorisation of Cantaloupe melon peel by freeze drying process

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.info:eu-repo/semantics/publishedVersio

EuFooD-STA Centre developed a free and open access digital library for the food sector

N/

UV-C radiation as an effective non-thermal process for ‘Cantaloupe’ melon juice decontamination

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.info:eu-repo/semantics/publishedVersio