This study was focused on a comparative analysis of two drying methods, such as convective and infrared drying, on the red beetroot purées with lactic acid bacteria, as a strategy for tailoring the health benefits of the selected plant. For both varieties, the total betalain contents varied from 13.95 ± 0.14 mg/g dry weight in Beta vulgaris var. cylindra when compared with 11.09 ± 0.03 mg/g dry weight in Beta vulgaris var. vulgaris, whereas significant differences were found in total phenolic and flavonoid contents. Significant drying induced changes were found in selected bioactives, in terms of total betalains, flavonoids, and polyphenols, which influenced the antioxidant activities of the purées, structure, and color parameters. In general, infrared technology was more protective, leading to an increase of 20% in flavonoids content. One logarithmic decrease in cell viability was observed in all powders samples. After the in vitro digestion, the betalains decreased, in both gastric and intestinal simulated juices, with a more pronounced profile in infrared processed purées. Textural and rheological analysis of the dried purées highlighted that the infrared drying is milder compared to the conventional one, allowing us to obtain powders with enhanced functional properties, in terms of bioactives content, cell viability, color, and structural and rheological behavior.
• Two methods were used to dry Băbească Neagră pomace together with probiotics. • The activation energies values suggested a higher temperature dependence for convective drying. • The lactic acid bacteria viable cells content decreased with 2 log during drying. • A wide polyphenolic content was highlighted in both powders. • Both powders showed antidiabetic potential.
Two main sources of fibers and bioactive compounds represented by pumpkin (Cucurbita maxima L.) and quince (Cydonia oblonga Mill.) were selected for the present study. The current changes in consumers behavior oblige manufacturers to develop new assortments of ready-to-eat products, considering their nutritional characteristics. Hence, this study aimed to process free sugar pumpkin and quince puree using a combination of freezing (−15 °C) and cooking at 95 °C for 20 min. Four variants of purees were obtained by using different combinations between pumpkin and quince (pumpkin puree, quince puree, and pumpkin and quince puree in ratios of 1:1 and 3:1). The samples were characterized in terms of complex interconnected analysis, which could provide further information for the added-value products. Thus, highest values of β-carotene content were attributed to pumpkin puree (P −5.34 ± 0.05 mg/g DW) and pumpkin and quince puree 3:1 (PQ 3:1 −3.78 ± 0.014 mg/g DW). These findings are also supported by the values of ABTS inhibition, which was registered as 71.32% for the P sample and 76.25% for the PQ 3:1 sample. The textural analysis revealed firmness values of 1.27 N for pumpkin puree and 2.33 N for quince puree. Moreover, the structural changes were minimum, while the cellular structure and some tissues were preserved intact.
28 October 2014 in Journal of Food Science and Technology
Two textural characteristics, elasticity modulus and firmness, were determined during the ripening process of Cascaval cheese, using both instrumental and sensorial techniques. Uniaxial compression was used to determine the textural characteristics and the results were compared with the ones obtained by sensorial analysis, revealing a good correlation. The chemical composition of cheese was also determined, including the nitrogen fractions (total nitrogen, water soluble nitrogen, non-protein nitrogen and phosphotungstic acid soluble nitrogen). The data thus obtained were statistically processed in order to find the differences between the samples, as well as to find the correlation between the techniques of analysis. The study showed that the ripening process of the Cascaval cheese is similar to the ripening of other pasta filata cheese. The moisture content decreases during maturation as a result of water evaporation. The concentration of nitrogen fractions increases during the ripening stage, and so do the firmness and elasticity modulus. The biochemical processes that occur during maturation largely influence the textural parameters and this is proved by both instrumental and sensorial analyses.