No abstract

No abstract

No abstract

The quality of strawberry fruits (cv. ''Clery'' and cv. ''Asia'') was studied and compared under the conditions of two different growing systems (under a high plastic tunnel and in the open field). Several chemical parameters were determined in the harvested fruits: dry matter, soluble solids, total acidity, ratio between sugars and acids, vitamin C, total phenols, non-flavonoid phenolic compounds, total anthocyanins, reducing sugars, sucrose, colour of fruits, and HPLC analysis of flavonols, flavanols, and phenolic acids content. The fruits of cultivar ''Clery'' had more antioxidant compounds than the fruits of cultivar ''Asia'' when grown in the open field. The fruits of both cultivars grown under a tunnel generally had good properties; however, the total phenol content and the non-flavonoid fraction were somewhat lower. Among the phenolic compounds, (þ)-catehin, (7)-epicatehin, ellagic, p-coumaric acid, quercetin, and kaempferol were identified and quantified using HPLC equipped with Photo Diode Array detection. The highest content of phenolic compounds was found in cv. ''Clery'' from the open field production. Analysis of antioxidant compounds has not shown statistically significant differences as a result of growing system or grown cultivar. Samples of strawberries grown under a high plastic tunnel, regardless of examined cultivar, had better basic chemical parameters. The mash colour also depends on cultivar and growing system. Keywords: strawberries; Fragaria x ananassa; cultivar; growing system; open field; high plastic tunnel; fruit quality La calidad de las frutas de la fresa (cv. ''Clery'' y cv. ''Asia'') se estudiaron y compararon en condiciones de dos diferentes sistemas de cultivo (bajo invernaderos altos de pla´stico y en campo abierto). Varios para´metros quı´micos se determinaron en las frutas recolectadas: materia seca, so´lidos solubles, acidez total, relacio´n entre azu´cares y a´cidos, vitamina C, fenoles totales, compuestos feno´licos no flavonoides, antocianinas totales, azu´cares reductores, sacarosa, color de fruto y ana´lisis HPLC de contenido de flavonoles, flavanoles y a´cido feno´lico. Frutas del cultivar ''Clery'' tuvieron ma´s componentes antioxidantes que los frutos del cultivar ''Asia'', cuando se cultivaron en campo abierto. Los frutos de ambos cultivares crecidos bajo invernaderos generalmente tuvieron buenas propiedades; sin embargo, los contenidos de fenoles totales y su fraccio´n de no flavonoides fueron algo menores. Entre los compuestos feno´licos, (þ)-catequina, (7)-epicatequina, a´cido ela´gico, a´cido p-cuma´rico, quercetina y kaempferol se identificaron y cuantificaron usando HPLC con detector de matriz de fotodiodos. Los contenidos ma´s altos de compuestos feno´licos se encontraron en el cultivar ''Clery'' obtenidos en produccio´n en campo abierto. El ana´lisis de compuestos antioxidantes no mostro´diferencias estadı´sticamente significativas en cuanto al sistema de cultivo o el cultivar. Las muestras de fresas crecidas bajo invernadero alto de pla´stico, independient...

This study investigated the status of bioactive compounds (phenolic compounds, carotenoids, and vitamin C), changes in color performance, and microbiological quality in smoothies preserved by high-pressure processing (HP) and thermal pasteurization (P) during cold storage at 4 °C for 21 days. Chemometric tools were used to select relevant variables that represent the most useful information for the fast and accurate quality assessment of smoothies. HP was performed at 350 and 450 MPa for 5 and 15 min at room temperature, respectively, while P was performed at 85 °C for 7 min. Smoothies were prepared by blending juices of apple (50%, v/v), carrot (20%, v/v), chokeberry (5%, v/v), Indian banana puree (10%, w/v), and almond drink (15%, v/v). The results obtained indicated that lower pressures with a shorter duration of HP showed higher levels of bioactive compounds in the smoothies, compared to the control samples. Compared to P, the HP samples exhibited a greater stability of bioactive compounds during shelf life. HP was found to be highly effective in reducing the native microflora of the smoothies, without subsequent microbial activation during storage. This study demonstrated the usefulness of the chemometric approach in interpreting complex datasets for the effective quality assessment of smoothies treated with different preservation technologies.