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Background: The heating of a green smoothie during an innovative semi-continuous microwave treatment (MW; 9 kW for 15 s) was modelled. Thermal and dielectric properties of the samples were previously determined. Furthermore, the heating effect on the main chemopreventive compounds of the smoothie and during its subsequent storage up to 30 days at 5 or 15 °C were studied. Such results were compared to conventional pasteurization (CP; 90 °C for 45 s) while unheated fresh blended samples were used as control (CTRL). Results: A procedure was developed to predict the temperature distribution in samples inside the MW oven with the help of numerical tools. MW-treated samples showed the highest sulforaphane formation after 20 days, regardless of the storage temperature, while its content was 2-fold reduced in CP samples. Storage of the smoothie at 5 °C is crucial for maximizing the levels of the bioactive compound S-methyl cysteine sulphoxide. Conclusion: The proposed MW treatment can be used by the food industry to obtain an excellent homogeneous heating of a green smoothie product retaining high levels of bioactive compounds during subsequent retail/domestic storage up to one month at 5 °C. The authors are grateful to Spanish Ministry of Economy and Competitiveness (MINECO) Project AGL2013-48830-C2-1-R and FEDER for financial support. We are also grateful to M. Otón for his skillful technical assistance

Background. Some algae are an excellent sources of vitamin B12, of special interest for vegetarian/vegan consumers, and of fucose to supplement fruit and vegetable beverages such as smoothies. Nevertheless, supplementation of smoothies with algae may lead to possible quality changes during smoothie shelf life that need to be studied. Therefore, the quality changes in fresh green smoothies supplemented (2.2%) with nine edible algae (sea lettuce, kombu, wakame, thongweed, dulse, Irish moss, nori, Spirulina and Chlorella) were studied throughout 24 days at 5 °C. Results. The initial vitamin C content – 238.7–326.0 mg kg−1 fresh weight (FW) – of a 200 g portion of any of the smoothies ensured full coverage of its recommended daily intake, and still supplying 50–60% of the recommended intake after 7 days. Chlorella and Spirulina smoothies showed the highest vitamin B12 content (33.3 and 15.3 µg kg−1 FW, respectively), while brown algae showed fucose content of 141.1–571.3 mg kg−1 FW. These vitamin B12 and fucose contents were highly maintained during shelf life. Conclusion. The Spirulina supplementation of a 200 g smoothie portion ensured full coverage of the recommended vitamin B12 intake, with lower vitamin C degradation, during a shelf life of 17 days. Furthermore, thongweed and kombu are also considered as excellent fucose sources with similar shelf life. The authors are grateful to Spanish Ministry of Economy and Competitiveness, Project AGL2013−48830−C2−1−R and FEDER for financial support. We would also like to thank SAKATA SEED IBERICA S.L. for providing Bimi® samples.