Search

As a fresh food, sweet potatoes are highlighted for their taste and appearance. In the industry, they are valued for their starch and sugar content. In both scenarios, much attention has been given to the composition of bioactive compounds. The application of abiotic stresses seems to induce an overproduction of these compounds in some vegetables. The objective was to examine the influence of harvest time on the synthesis and accumulation of bioactive compounds in varieties of minimally processed sweet potatoes with different flesh colors. Sweet potato cultivars (Beterraba, Jerimum, Mãe de Família Roxa, and BRS Cuia) were harvested at 120, 150, and 180 days after planting, then subjected to minimal processing and stored at 5 ºC for 10 days. The most recommended time for harvesting sweet potatoes in semi-arid conditions for minimal processing by the industry is between 150 and 180 days. This is the period when the sweet potatoes exhibit the best quality for fresh consumption, as detected in ‘Mãe de Família Roxa’ and ‘Jerimum’. ‘BRS Cuia’ harvested at 120 days showed the highest phenolic compound levels, the highest polyphenol oxidase and peroxidase enzyme activities, and the most intense browning symptoms. In addition to its starch content, it can be used as a raw material for the extraction of phenolic compounds of interest. ‘Beterraba’ showed low sugar values, rendering them unfavorable for fresh consumption or minimal processing. However, this cultivar also exhibited a high content of carotenoids, making them bio-factories for the food and pharmaceutical industries. RESUMO Como alimento fresco, a batata-doce se destaca pelo sabor e aparência. Na indústria, é valorizado por seu teor de amido e açúcar. Em ambos os cenários, muita atenção tem sido dada à composição dos compostos bioativos. A aplicação de estresses abióticos parece induzir uma superprodução desses compostos em algumas hortaliças. O objetivo foi examinar a influência da época de colheita na síntese e acúmulo de compostos bioativos em variedades de batata-doce minimamente processadas com diferentes cores de polpa. As cultivares de batata-doce: Beterraba, Jerimum, Mãe de Família Roxa e BRS Cuia foram colhidas aos 120, 150 e 180 dias após o plantio, submetidas ao processamento mínimo e armazenadas a 5 ºC por 10 dias. A época mais recomendada para a colheita da batata-doce em condições semi-áridas para a indústria de processamento mínimo foi entre 150 e 180 dias, período em que a batata-doce apresentou melhor qualidade para consumo in natura em destaque para 'Mãe de Família Roxa' e 'Jerimum'. A ‘BRS Cuia’ colhida aos 120 dias apresentou os maiores teores de compostos fenólicos, as maiores atividades das enzimas polifenoloxidase e peroxidase e os sintomas de escurecimento mais intensos, podendo ser utilizado como matéria-prima para a extração de compostos fenólicos de interesse, além do amido. A ‘Beterraba’ apresentou baixos valores de açúcar, tornandoos desfavoráveis para consumo in natura ou processamento mínimo. No entanto, esta cultivar também apresentou um alto teor de carotenóides, tornando-os biofábricas para as indústrias alimentícia e farmacêutica.

The objective was to carry out a physicochemical characterization of the mucilage obtained from different sizes of cladodes harvested at different times. Nopalea cochenillifera Salm Dyck cladodes were collected in two sizes (100 to 230 and 240 to 300 mm), at two different times (6 am and 8 pm), and processed for mucilage extraction. This was dried in an oven, and then hydrated and kept at 5 °C for 12 days. The mucilage yield after harvest was quantified, in addition to the characterization of the main bands in the infrared region. In the mucilage, the following physicochemical analyzes were performed: K+ and Na+ content, electrical conductivity, titratable acidity, pH, total phenolic compounds, vitamin C, total soluble solids, total soluble carbohydrates, total soluble proteins after harvest (day 0), and to the 12 days of storage at 5 ºC. Correlation between the variables was determined through principal component analysis (PCA). The highest mucilage yield was obtained in cladodes harvested at 6 am, regardless of size. The 6 am harvest showed higher acidity and protein content and lower concentrations of soluble solids, EC, Na+, K+, vitamin C, carbohydrates, and phenolic compounds. In conservation, the mucilage of the cladodes with sizes between 100 and 230 mm and the harvest at 6 am showed greater stability. Principal component analysis (PCA) showed a tendency of formed groups between different sizes, harvest times, and conservation days, indicating that different conditions for obtaining the cladodes result in differences in the composition and stability of the mucilage. Thus, the results show that, in addition to the climatic conditions, as proposed by other authors, the harvest time and the size of the cladode modulate the physicochemical and important ion composition and stability, which can change the technological and industrial applications of mucilage.

This study proposes to characterize hydrated and refrigerated mucilage obtained from cladodes of clones of prickly pear cactus harvested during the drizzle and dry seasons in the semiarid of Brazil. Cladodes of Opuntia stricta [Haw.] Haw (Orelha de Elefante Mexicana [OEM] clone) and Nopalea cochenillifera Salm Dyck (IPA Sertânia [IPA] and Miúda [MIU] clones) were harvested at 6 am and extracted mucilage. The main bands in the infrared region were characterized. Physicochemical analyses were performed on day zero and at 12 days. Cladodes harvested in the dry season showed higher mucilage yield and soluble solid, total soluble carbohydrate, and K+, for the three clones. The OEM clone also exhibited significant increases in pH, Na+, and electrical conductivity when harvested in the dry season than in the wet season. In addition, the mucilage extracted from the Opuntia cladodes did not have changes in the carbohydrate, titratable acidity, or total soluble protein levels. The IPA and MIU clones, in turn, were characterized by parameters that remained stable during conservation (phenolic compounds, titratable acidity, K+ and Na+). The spectroscopic profile was similar for all studied clones. The principal component analysis allowed the formation of clusters between seasons and conservation times. It is suggested that the cladodes of the genus Nopalea showed better potential in the manufacture of edible films and coatings. The cladodes of the genus Opuntia, for the use of mucilage as ingredients in foods such as bread, pasta, and others, making them with better functional properties. Therefore, these factors should be considered for the use of mucilage in the industry.

Cultivation conditions are determining factors that affect the quality of cut flowers. The objective of this study was to evaluate the vegetative growth, flowering and vase life of commercial gladiolus cultivars under different shading conditions in the Brazilian semi-arid region. Two cultivars of gladiolus (Jester and Rose Friendship) were grown under two conditions: full sun and 70% shade. Biometrics were evaluated 60 days after planting and the growth rate of the crop was evaluated at 15-30, 30-45 and 45-60 days for the variables: number of tillers, stem diameter, number of leaves and plant height. After 45 days, the fresh weight, dry weight and total relative water content of the area and root parts of the plants were evaluated. After the harvest, the stems were kept at a temperature of 22±3 °C and relative humidity (RH) of 60%. Visual assessment, pH of the solution, variation in the volume of water and loss of fresh mass were measured every two days. Cultivation with 70% shading resulted in greater accumulation of biomass in the aerial part of gladiolus plants, greater neck diameter and height. The Rose Friendship cultivar underwent a greater translocation of dry matter to the aerial part of the plants, resulting in greater height. On the other hand, the gladiolus stems from cultivation under full sun conditions resulted in longer vase life, 10 days under conservation conditions at 22±3 °C and RH 60%. Resumo As condições de cultivo são fatores determinantes que afetam a qualidade das flores de corte. Diante disso, objetivou-se, neste estudo, avaliar o crescimento vegetativo, floração e vida de vaso de variedades de gladíolos comerciais no semiárido brasileiro, sob diferentes condições de sombreamento. Duas variedades de gladíolos (Jester e Rose Friendship) foram cultivadas em duas condições: sol pleno e 70% de sombreamento. Avaliou-se a biometria em 60 dias após o plantio e a taxa de crescimento da cultura aos 15-30, 30-45 e 45-60 dias para as variáveis: número de perfilhos, diâmetro do colo, número de folhas e altura da planta. Após 45 dias, avaliou-se a massa fresca, massa seca e conteúdo relativo de água total da parte área e da parte radicular das plantas. Após a colheita, as hastes foram mantidas em temperatura de 22±3 °C e umidade relativa (UR) de 60%. A cada dois dias, realizou-se avaliação visual, além de avaliação do pH da solução, variação no volume de água e perda de massa fresca. O cultivo com 70% de sombreamento resultou em maior acúmulo de biomassa na parte aérea das plantas de gladíolos, maior diâmetro do colo e altura. A variedade Rose Friendship resultou em maior translocação de massa seca para a parte aérea das plantas. Isso resultou em maior altura. Por outro lado, as hastes de gladíolos provenientes do cultivo nas condições de pleno sol resultaram em maior vida de vaso: 10 dias em condições de conservação a 22±3 °C e UR 60%.