RCAAP Repository

Abstract The propolis produced by stingless bees of the tribe Meliponini is a viscous product that contains the resin collected from buds, leaves and plant exudates, mixed with salivary secretions, wax and soil. The species Scaptotrigona aff. postica (Latreille, 1807), (Hymenoptera, Apidae, Meliponinae) popularly known as “tubi” in Maranhão State, Brazil, does not mix soil to produce its propolis. The propolis from S. postica harvested in Barra do Corda, Maranhão State, is popularly used in the treatment of wounds and respiratory illnesses. The hydroalcoholic extract of this propolis, rich in flavone-6,8-di-C-glycosides (vicenin-2 and schaftoside), pyrrolizidine alkaloids derived from retronecine, catechin and caffeoylquinic acid derivatives exhibited antiviral activity against the herpes simplex and rubella viruses. The aim of this study was to increase knowledge about the chemical composition of the S. postica propolis by analyzing non-polar extracts obtained using hexane and chloroform as the solvents, by GC-EI-MS. A total of 15 constituents were identified comparing their respective mass spectral data with those available in the NIST data bases and those reported in the literature. The main constituents detected were the phenolic lipids, known as cardanols, 3-(4,7-heptadecadienyl) phenol (5), 3-(10-heptadecenyl) phenol (7), 3-heptadecylphenol (9) and 3-pentadecyl phenol or hydrocardanol (13), which predominated in the hexane extract, while the predominant constituents in the chloroform extract were 3-pentadecyl phenol or hydrocardanol (13) and 3-(8-pentadecenyl) phenol (12). The antioxidant, antitumoral, antifeedant, cytotoxic, anticarcinogenic, antiproliferative, antimicrobial, antileishmanial and larvicidal activities of the cardanols have been demonstrated in many studies.

Abstract Thistle flowers, and particularly their stigmas, are used to coagulate milk in the production of a number of traditional Portuguese cheeses due to their high milk-clotting activity provided by the high content of aspartic proteases. The aim of the present work was to determine the mass transfer properties of thistle flower under different drying conditions: natural drying and convective drying. Convective drying took place in a convection chamber set at different temperatures (35 to 65 °C) and the process was terminated when the sample presented a moisture content of about 5% or less. The traditional drying method was also used, placing the thistle flowers in a dry place sheltered from the sun, and leaving them to dehydrate at the variable room temperature. The present work allowed for the conclusion that convective drying was much faster than natural drying, and that the drying rate increased with temperature. The drying curve revealed an initial constant rate period followed by a falling rate. All the five thin layer models tested to fit the experimental data were shown to adequately describe the drying of the thistle flowers, but the best one was the Page model. The drying constant increased with temperature as did the effective diffusivity and the mass transfer coefficient. The results allowed one to estimate the activation energy for moisture diffusion (57 kJ/mol) and for convective mass transfer (78 kJ/mol). Thus this study showed the possibilities for designing efficient drying processes for the thistle flower used for milk-clotting in the manufacture of traditional cheeses.

Abstract Yacon syrup (YS) and cashew apple extract (CAE) are products with high concentrations of bioactive compounds such as fructooligosaccharides and carotenoids, which exhibit prebiotic and antioxidant properties. The objective of this work was to evaluate the impact of YS and CAE on the chemical, physical, physicochemical and sensory properties when these products were incorporated into natural yoghurt. Initially, the YS and CAE were characterized by chemical, physical and physicochemical analyses. The bioactive compounds, such as carotenoids, fructooligosaccharides and phenolic compounds, and the antioxidant activity were also determined. After characterization, natural yoghurt was supplemented with YS and CAE in different concentrations as follows: formulation A (non-supplemented yoghurt, as the control), formulation B (yoghurt with the addition of 20% of YS), formulation C (yoghurt with the addition of 20% of YS and 10% of CAE) and formulation D (yoghurt with the addition of 20% of YS and 20% of CAE). The formulations were evaluated for their sensory acceptance (overall acceptance, texture and appearance) and purchase intent, and were then characterized by chemical, physicochemical and physical analyses. The results indicated that the YS and CAE presented high concentrations of bioactive compounds, such as fructooligosaccharides and carotenoids, respectively. In addition, when the yoghurt was supplemented with these products, this induced changes in the chemical, physicochemical and physical properties of the yoghurt. In the sensory analysis, all the formulations presented good acceptance. The results indicated that yoghurt could be considered as an interesting vehicle for YS and CAE, products with high levels of bioactive compounds that may exert beneficial effects on human health.

Abstract This study aimed to quantify the concentration of natamycin in the rind and verify its migration in Gorgonzola type cheese, as well as evaluating the decline of natamycin in Blue cheese during maturation. Eight samples of Gorgonzola cheese were purchased in supermarkets of which six were produced in different regions of Brazil, one in Argentina and one in Italy. The rinds of four of the eight cheese samples presented natamycin concentrations above 5 mg/kg, three of these samples being from Brazil and one from Argentina. With the exception of the Italian cheese, all the samples showed natamycin inside the cheese mass (up to 6 mm from the rind). To evaluate the rate of decline during the ripening of Blue cheeses, samples were collected from an industry as from day 0 (day of manufacture) up to the 45 days of ripening. The results showed that, after 45 days of ripening for cheese immersed in a 3% natamycin solution, the concentration in the rind was 4 times the amount allowed by the legislation (5 mg/kg). However, for immersion in a 1.5% natamycin solution, after 25 days of ripening, the antifungal concentration was in accordance with the standards established by the legislation.

Abstract Oleaster (Elaeagnus angustifolia L.) is a fruit with special nutraceutical value which grows under a wide range of climatic conditions in Europe and Asia. In the present study, the effects of oleaster flour (15%, 30% and 45%) and active gluten at (0 and 3%) on the physical, chemical and sensory properties of sponge cakes were assessed. The best sample was selected based on the qualitative properties and compared with the control with respect to the staling rate and nutritional aspects. In order to decrease the calories, the sucrose content of the selected sample was replaced with potassium acesulfame and isomalt at the levels of 30%, 50% and 70%. Oleaster flour increased the density but decreased the hardness and cohesiveness of the cake. Active gluten decreased the density and hardness but increased the cohesiveness and springiness. Considering the qualitative properties of the sponge cakes, the sample containing 30% oleaster flour and 3% gluten (30 OFG) was selected as the best. Replacement of the sucrose in 30 OFG increased the hardness, density, redness and yellowness of the crumb. With 30% sucrose replacement, the quality of the product was adequately maintained. The use of oleaster significantly increased the calcium, potassium, crude fibre, fat and total phenolic compound contents of the sponge cakes as compared to the control. The sample containing 30% oleaster flour and 3% gluten with 30% sucrose replacement showed appropriate physicochemical, textural and sensory properties.

Abstract The aim of this work was to evaluate the crystal size distribution (CSD) and microscopy of the crystalline phase in isothermal lactose crystallization, using a high seeding concentration (dense phase). In-line monitoring was carried out using Focused Beam Reflectance Measurement (FBRM) and Particle Vision Measurement (PVM) probes in a stainless steel trunk-conical shaped jacketed crystallizer. The vibratory shaking system consisted of two perforated discs coupled to a movable axle. A conventional crystallization unit, with a three-blade propeller attached to a stainless steel shaft, was used for comparison. Concentrated cheese whey, purified with an organic coagulant, and commercial lactose solutions were used. Crystallization was improved in the high-purity solutions. Microparticles and/or aggregates appeared before seeding, mainly in the purified cheese whey solution, in which there are impurities. Secondary nucleation was present in both the vibratory agitation and conventional rotary agitation systems, being intensified by increases in agitation. Crystallization in a vibratory system should be carried out with a vibration frequency of 250 rpm, since an increase to 400 rpm reduced the amount of larger crystals.

Abstract Yogurt is an important source of many biologically active peptides with specific health benefits. The majority of the bioactive peptides produced during yogurt manufacture are related to angiotensin converting enzyme inhibitory (ACE-I) peptides. The present study evaluated the proteolysis and angiotensin converting enzyme (ACE) inhibitory activities of non-fat probiotic yogurt supplemented with sodium caseinate (0 to 4%), and Mentha piperita (peppermint) extract (0 to 0.4%) during 20 days of storage. Good correlation (R = 0.90) was found between the growth of Lactobacillus casei LFTI® L26 and ACE inhibition in all samples during the initial stages of storage, as compared to the control yogurt, with a significant (p < 0.05) decrease after storage. The results showed that the addition of sodium caseinate and peppermint extract had a significant (p < 0.05) effect on proteolysis and the viability of L. casei LFTI® L26, enhancing the ACE activity. The IC50 values of the sample containing 0.4% of peppermint and of the sample containing 4% of sodium caseinate were 0.12 and 0.02 mg/mL respectively. The results showed that the use of 4% of sodium caseinate and 0.4% of peppermint extract could provide higher probiotic viability (1.3×107cfu/g) on the 20th day of storage.

Abstract In Peru, approximately 20% of the production of avocado var. Hass is discarded due to its low quality, and sold at low prices in local markets. The aim of this study was to optimize the blanching time and temperature to produce avocado pulp, using low quality discarded fruits as the raw material. The process was optimized using Response Surface Methodology with a 22 central composite rotational design (R2 ≥ 0.75; p < 0.05). The independent variables studied were the blanching time (0, 1.5, 5, 8.5, 10 min) and temperature (65, 68, 75, 82, 85 °C), where the avocados were blanched by immersion (with peel), and the pulp extracted, processed, vacuum sealed (0.035 MPa) and stored under refrigeration at 5 °C for 49 days. The low quality discarded avocados were shown to be ideal for pulping, since 98% of the fruits had an oil content below 15% with an average pulp yield of 79.23%. The results indicated that longer blanching times and higher temperatures of above 5 min and 75 °C, respectively, retained the green colour and increased the brightness of the pulp, avoiding enzymatic browning. In addition, the increase in both contributed to the stability of the product acidity and pH level, extending its shelf life. However, in the sensory analysis, the pulp submitted to temperatures above 82 °C obtained the lowest scores for taste, odour and general acceptance due to the presence of a bitter taste and unpleasant odours in the pulp. The central point trials (5 min; 75 °C) presented the best scores for the independent variables such as colour, taste, odour and sensory texture, also showing good physicochemical stability with a shelf life of 37 days.

Abstract This study investigated the effects of different heat treatments, namely boiling, microwaving and pressure cooking, on the reduced ascorbic acid content and antioxidant activity in Momordica charantia extracts. The total antioxidant activity of M. charantia extracts was determined by ferric reducing-antioxidant power and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays. The reduced ascorbic acid content was estimated by ferric reducing-antioxidant power-ascorbic acid assay and confirmed by high performance liquid chromatography. Regardless of the cooking method, all cooked M. charantia extracts had significantly (p < 0.05) higher total antioxidant activity, radical scavenging potency and reduced ascorbic acid content than the uncooked sample. The decreasing order of reduced ascorbic acid in M. charantia was as follows: microwaved > boiled > pressure-cooked > uncooked. The reduced ascorbic acid in M. charantia strongly correlated with the total antioxidant activity (r = 0.958, p < 0.05) and radical scavenging potency (r= 0.951, p < 0.05). The principle component analysis showed that 87% of the variation in the antioxidant values of M. charantia extracts was attributed to the different cooking methods. Heat treatment either by boiling or microwaving for a short period of time (10 minutes) improved the reduced ascorbic acid content in the M. charantia extract. This study showed that the reduced ascorbic acid could be retained under high temperature and pressure in M. charantia extracts.

Resumo Objetivou-se com este trabalho avaliar o perfil físico-químico de sucos elaborados com uvas das variedades Vitis rotundifolia Regale, Noble, Summit e Carlos. O trabalho foi realizado na Epagri-Videira/SC, nas safras 2016, 2017 e 2018. O delineamento experimental utilizado foi um fatorial duplo (variedade × safra), de forma inteiramente casualizada e com três repetições. As análises físico-químicas realizadas foram: acidez total (AT), teor de sólidos solúveis (SS), relação SS/AT, pH, açúcares redutores, densidade e cor. Em relação ao pH, ‘Regale’ e ‘Carlos’ apresentaram valores que se mantiveram na faixa de 2,82 a 2,98, enquanto para ‘Noble’ e ‘Summit’, os valores foram superiores, chegando a 3,30. A acidez titulável dos sucos de ‘Regale’ e ‘Noble’ se destacou das demais variedades em ambas as safras avaliadas, devido aos teores de acidez mais elevados. Para o teor de sólidos solúveis totais, na safra 2016, apenas os sucos da variedade ‘Summit’ atingiram o valor de 14,00 °Brix, teor mínimo exigido para comercialização como suco integral perante a legislação brasileira. Os sucos dessa variedade obtiveram a maior relação SS/AT nas três safras avaliadas, com valores próximos a 30, comportamento diverso dos sucos de ‘Regale’, que apresentaram as menores médias para esta variável, com valores em torno de 10. As variedades tintas originaram sucos mais ácidos em comparação às variedades brancas. A variedade ‘Summit’ apresentou a melhor relação açúcar/acidez, apresentando aptidão para a elaboração de sucos nas três safras pesquisadas. ‘Regale’ e ‘Noble’ apresentaram prejuízos na produtividade e sanidade na safra 2016, no entanto, mostraram-se aptas ao processamento de suco nas safras 2017 e 2018. Os sucos da variedade ‘Carlos’ não atingiram o teor mínimo de 14 °Brix em nenhuma das três safras estudadas, fator que impossibilita a classificação destes como suco integral.

Abstract This study aimed to develop goat’s milk cheese to conserve the major milk constituents. Household dahi (yoghurt) is an inexpensive source of starter cultures that contains several types of microorganism of which most are thermophilic in nature and can be used in the production of goat’s milk cheese. Different concentrations of dahi (0.5%, 1.0%, 1.5%, 2.0% and 2.5%) were used to prepare the cheeses following the standard procedure for cheese manufacturing. The cheeses were analysed for their physicochemical, textural and organoleptic parameters. The highest yield was recorded for T1.0% (17.33%) and the lowest for T2.5% (15.58%). Significant (p < 0.05) differences were found for the pH, acidity and moisture content of the different goat’s milk cheese samples. The moisture content was highest in T0.5% (59.30) and lowest in T2.5% (52.20). The texture profile was significant (p < 0.05) for firmness, adhesiveness, gumminess and chewiness between the treatments. The sensory scores indicated that T1.0% was preferred by the panellists, followed by T1.5% and then the other treatments. It was concluded that goat’s milk cheese could be prepared with good quality characteristics using 1% dahi as the starter culture.

Abstract In this paper the physicochemical characteristics and the flow decline occurring during the reverse osmosis of skim milk, were analysed. The flow decline was evaluated using the resistances in series, the blocked pore models and a second conjugated model that combined the blocked pores with the development of a filter cake. The main resistance found was the concentration by polarization, which was mainly influenced by the complete blocking of the pores. The conjugated model was capable of predicting the flow decline of the process. With respect to the physicochemical properties, more than 98% of the lactose, protein, oils and fats were retained, demonstrating the efficiency of the process.

Resumo O patauá é uma fruta amazônica que, devido às suas propriedades sensoriais e nutricionais atrativas, tem despertado o interesse da comunidade científica. Entretanto, o elevado conteúdo de umidade confere alta perecibilidade ao produto fresco. Assim, objetivou-se estudar a cinética de secagem convectiva e determinar as propriedades termodinâmicas da polpa de patauá. A secagem foi realizada sob diferentes temperaturas (40, 50 e 60 °C) e espessuras da camada (0,3 e 0,6 cm), com velocidade do ar constante em 1,8 m s-1. Diferentes modelos de secagem em camada fina foram ajustados aos dados experimentais. O aumento da temperatura do ar e a diminuição da espessura da camada resultaram em aumento da taxa de remoção de umidade e, portanto, reduziram o tempo total de processo. Com base nos parâmetros estatísticos, o modelo de Midilli foi o que melhor descreveu a cinética de secagem das amostras para todas as condições avaliadas. Os coeficientes de difusão efetivos aumentaram com a elevação da temperatura do ar, apresentando magnitudes na ordem de 10-10 m2 s-1 e sua dependência com a temperatura foi representada pela equação de Arrhenius, com energia de ativação (Ea) de 32,41 e 40,10 kJ mol-1 para as espessuras de 0,6 e 0,3 cm, respectivamente. As variações de entalpia (ΔH) e de entropia (ΔS) reduziram-se com a elevação da temperatura de secagem, sendo menores na amostra desidratada na camada de 0,6 cm, enquanto que a variação na energia livre de Gibbs (ΔG) foi aumentada com a ampliação da temperatura, sendo mais elevada na secagem com camada de 0,3 cm.

Resumo É apresentado um estudo taxonômico de Metteniusaceae das cangas da Serra dos Carajás, no estado do Pará, Brasil. Uma espécie foi encontrada: Emmotum nitens, distribuída exclusivamente na América do Sul, com registros para o Brasil e Bolívia. São apresentadas uma descrição detalhada, ilustrações, fotografias, comentários sobre morfologia, distribuição e fenologia da espécie.

Resumo Passifloraceae é caracterizada principalmente pelo hábito lianescente, tendo Passiflora como gênero mais representativo. Na Serra dos Carajás foram registradas 12 espécies, mas nas áreas de canga ocorrem apenas P. ceratocarpa, P. glandulosa, P. tholozanii e Passiflora sp1. Neste estudo são apresentadas descrições, ilustrações e comentários morfológicos para as quatro espécies.

Resumo Um tratamento taxonômico para as espécies de Phyllanthaceae das cangas da Serra dos Carajás, no estado do Pará, é apresentado. O estudo foi baseado em coleções depositadas nos Herbários BHCB, IAN, INPA, MG e NY, além de amostras observadas no campo. Foram registradas cinco espécies de Phyllanthus, como seguem: Phyllanthus carolinensis, P. hyssopifoliodes, P. minutulus, P. orbiculatus e Phyllanthus stipulatus. São apresentadas descrições, chave taxonômica, ilustrações e comentários para as espécies.

Resumo Este estudo inclui o levantamento de Phytolaccaceae para as cangas da Serra dos Carajás, Pará, Brasil, e fornece descrições detalhadas, ilustrações e comentários morfológicos da única espécie registrada na área de estudo, Phytolacca thyrsiflora, amplamente distribuída nas Américas de Norte a Sul.

Resumo Duas espécies de Picramniaceae foram registradas na Serra dos Carajás, Pará, Brasil, pertencentes ao gênero Picramnia: P. ferrea e P. latifolia. Apenas a primeira foi registrada nas áreas de cangas da Serra, sendo endêmica da área. O presente estudo taxonômico apresenta descrição morfológica, ilustrações detalhadas e comentários diagnósticos de P. ferrea.

Resumo Apresenta-se um estudo florístico das espécies de Polygalaceae ocorrentes nas cangas da Serra dos Carajás (Pará). São apresentadas descrições, chaves taxonômicas, ilustrações e comentários taxonômicos dos táxons. Neste estudo foram encontradas seis espécies distribuídas em quatro gêneros: Bredemeyera divaricata, B. floribunda, Caamembeca spectabilis, Polygala adenophora, Securidaca diversifolia e S. rivinifolia, nenhuma delas endêmica da região ou do estado do Pará.

Resumo Este estudo apresenta a descrição detalhada, ilustração e comentários morfológicos das duas espécies de Pontederiaceae registradas para as cangas da Serra dos Carajás, no estado do Pará: Heteranthera oblongifolia e Heteranthera reniformis. Esse é o primeiro registro de H. oblongifolia para a região Norte do Brasil.