Quality of fresh-cut strawberry

The aim of this work was to study the physical, chemical, physiological and microbiological changes during the flow chart of fresh-cut strawberry. Strawberry cvs. Camarosa, Dover and Tudla, derived from experimental area of the Universidade Federal de Viçosa, were selected by color (red ¾) and absence of wound. Afterwards, the minimal processing was evaluated, as follows: fast cooling, water and ice, removal of the calyx followed by conservation at 5±0.5°C and 90-95% RH for 13 days, sanitation, drainage, cut in halves. Removal of the calyx did not result significant difference for fresh weight, total soluble solids, total titratable acidity, pH and ratio TSS/TTA. The rapid cooling resulted in lower electrolyte leakage and respiratory rate, especially sanitized fruits. Sanitization by immersion in chlorine solution slowed the growth of fungi and yeast. Drainage for 20 minutes eliminated practically all water on the surface of the fruits. The fresh-cutting did not affect the visual and nutritional quality of strawberries like appearance, microbiot, vitamin C, anthocyanins and phenolic compounds, consisting of alternative market potential economically viable.O objetivo deste trabalho foi estudar mudanças físicas, químicas, fisiológicas e microbiológicas durante o fluxograma de processamento mínimo de morango. Morangos das cultivares Camarosa, Dover e Tudla oriundos de área experimental da Universidade Federal de Viçosa, foram selecionados por cor (¾ vermelho) e ausência de danos. Posteriormente, foi avaliado o fluxograma de processamento mínimo: resfriamento rápido, água e gelo; remoção do cálice acompanhado de conservação a 5±0,5ºC e 90-95% UR, por 13 dias; sanitização; drenagem; corte, em metades. A remoção do cálice não resultou diferença significativa para massa fresca, sólidos solúveis totais, acidez total titulável, pH e razão SST/ATT. O resfriamento rápido ocasionou menores extravasamentos de eletrólitos e taxa respiratória, sobretudo nos frutos sanitizados. A sanitização por imersão em solução de cloro retardou o crescimento de fungos e levedura. A drenagem por 20 minutos eliminou praticamente toda a água na superfície dos frutos. O processamento mínimo não afetou a qualidade visual e nutricional dos morangos como aparência, microbiota, vitamina C, antocianinas e compostos fenólicos, consistindo em alternativa de mercado potencial economicamente viável

Modeling the Impact of the Type of Cutting and Storage Temperature on the Bioactive Compound Content, Phenylpropanoid Metabolism Enzymes and Quality Attributes of Fresh-Cut Strawberries

The aim of this work was to model the effect of the type of cutting (whole without hull, halved, and quartered), storage temperature (2, 6, and 13 °C) and time on the changes of bioactive compounds, phenylpropanoid metabolism enzyme activities, and quality attributes of fresh-cut strawberries. The effect of increasing the intensity of wounding revealed an activation of the phenylalanine ammonia lyase (PAL) enzyme, with the consequent synthesis of phenolic compounds. Results revealed that quartered strawberries stored at 2 °C for 15 days accumulated up to 22% more phenolics than whole strawberries. The changes on quality parameters (soluble solids, pH, and color), total anthocyanins, and polyphenol oxidase were adequately fitted with zero order kinetic. All rate constants of these attributes, except for anthocyanins, fitted appropriately with Arrhenius equation. Changes on total phenolic contents and on PAL activity were fitted with a consecutive reaction mechanistic kinetic model. The rate constants of phenolics kinetic showed no dependence with temperature. However, rate constants of PAL activity fitted appropriately with Arrhenius equation. This global study offers a better understanding of the effects of processing and storage conditions on general quality, bioactive compounds, and phenylpropanoid metabolism enzymes of fresh-cut strawberries.Fil: Van de Velde, Franco. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; ArgentinaFil: Fenoglio, Cecilia Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; ArgentinaFil: Piagentini, Andrea. Universidad Nacional del Litoral. Facultad de Ingeniería Química; ArgentinaFil: Pirovani, Maria Elida. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentin

Biodegradable PLA (polylactic acid) hinged trays keep quality of fresh-cut and cooked spinach

This work examines the effects of packaging using two different polymeric trays with hinged lids, polyethylene terephthalate (PET) and polylactic acid (PLA), on fresh-cut and cooked spinach (Spinacia oleracea). Samples were stored in a cold room for 16 days at 4 °C. Chemical (total pigments, total polyphenols, ascorbic acid, antioxidant activity), physical (water activity), technological (colour evaluation), sensorial (aroma, visual appearance and water accumulation) and microbial (total aerobic mesophilic and psychrotrophic counts) parameters were tested. Both polymeric trays maintained the overall quality of fresh spinach for 6 days but spinach stored in PLA trays maintained its flavour longer. A significant increase in total polyphenols, antiradical activity, total carotenoids as well as a decrease in ascorbic acid in fresh spinach was observed in the first 3 days of storage in both samples. Unfortunately, the PLA package accumulated condensed water. The total microbial load of fresh-cut spinach reached about 6.3–7.3 log CFU g(−1) within 8 days. Cooked spinach packed in PLA and PET polymeric hinged trays showed the same behaviour as fresh spinach in terms of quality and shelf life. In conclusion, PLA plastic hinged trays can be used for packaging fresh-cut and cooked cut spinach, but the problem of condensed water must be solved