Roberto N. Maeda

Desenvolvimento e aceitabilidade de geléia dietética de cubiu (Solanum sessiliflorum Dunal) Development and acceptability of a low calorie cubiu (Solanum sessiliflorum Dunal) jam

With the aim of improving utilization of Amazonian fruits and satisfying the growing demand for new products in the market, we formulated a low calorie cubiu jam with xylitol as a sucrose substitute, and evaluated its shelf life and acceptability. The cubiu fruits from the Experimental Station of the National Research Institute of Amazonia (INPA) were harvested, bleached, pealed, ground, sieved, and stored in plastic bags at –20xa0± 1 °C until their utilization. At the same time, triplicate samples of the cubiu pulp were analysed for humidity, protein, lipids, soluble and insoluble fibers, ash, pH, total acidity, total and reducing sugars, and phenolic compounds. The conventional and the xylitol-based jams were prepared with a 1:1 proportion of pulp:sucrose or pulp:xylitol, respectively. The mixture was concentrated up to 65° Brix with pH adjustment and pectin addition. The jams were analyzed for protein, lipids, ash, pH, acidity, sugar, and phenolic compounds. The shelf life was evaluated through monthly physicochemical, microbiological, and sensory analyses for a period of 180 days. The results showed no statistical difference between the acceptability of conventional and xylitol-based jams and presented the same physicochemical, microbiological stability during storage. Xylitol can be a viable sucrose substitute for the preparation of cubiu jams.

Processamento e avaliação da vida-de-prateleira do tucumã (Astrocaryum aculeatum Meyer) desidratado e pulverizado

The present study had as objective to process tucuman by dehydration and pulverization and to evaluate its shelf-life in different types of packaging and storage temperatures. The edible part of the fruit was dehydrated, triturated and passed through a sieve to standardize granule diameter, then packed in three different types of packaging (polyethylene plastic film, laminated film, and steel can) and stored at different temperatures (4 and 24 °C). The in natura and dehydrated fruits were analyzed for moisture content, pH, acidity, total and reducing sugars, proteins, lipids, ash, carbohydrates, energy, β-carotene and retinol equivalent. The dehydrated and pulverized tucuman was analyzed every 30 days during the 150 days of storage for peroxide, acid and iodine values and microbiological parameters. The constituents that stood out in the in natura fruits as well as in the dehydrated and pulverized fruits were lipids, carbohydrates and, consequently, energy and β-carotene. Regarding shelf-life, all treatments presented good chemical and microbiological stability during the 150 days of storage. It can be concluded that dehydrated and pulverized tucuman, independent of the type of packaging and storage temperature, can be stored and consumed for up to 150 days, allied to the nutritional potential as an energy and β-carotene source.

Determinação da formulação e caracterização do néctar de camu-camu (Myrciaria dubia McVaugh)

Camu-camu is a wild fruit distributed throughout the banks of lakes and rivers in Amazonia, which presents a great economical potential on account of its agronomic, technological and nutritional features. Nevertheless, its consumption is still restricted due to its high acidity, bitterness, and skin astringency, thus needing the use of proper technologies for its use. The objective of the present study was to determine the ideal camu-camu nectar formulation and to assess its physical and physical-chemical characteristics. Nine formulations with different pulp and sugar concentrations, which were submitted to a preference test by a board of 30 untrained tasters, were prepared in order to obtain the nectar. Among the tested formulations, the one presenting the highest degree of preference was prepared with 17.5% of sugar and 17% of pulp, presenting values of LHunter 32.00, aHunter 3.22 and bHunter -0.38, ascorbic acid 382.07 mg/100 mL, anthocyanins 2.51 mg/100 g and 89.1% global acceptance. The findings demonstrate the camu-camu nectars nutritional and technological viability on account of its attractive colour, good tasting flavour, and pleasant aroma, as well as for being a source of vitamin C.

Estabilidade de ácido ascórbico e antocianinas em néctar de camu-camu (Myrciaria dubia (H. B. K.) McVaugh)

Camu-camu is a fruit with a remarkable nutritional potential due to its high ascorbic acid content. Hence, the aim of the present study is to evaluate the stability of ascorbic acid and pigments present in camu-camu nectar stored under different light and temperature conditions. Fruits were depulped and assessed as to their physico-chemical characteristics. Nectar obtained from the pulp was placed in plastic bottles and stored at room temperature and refrigerated, with and without light, and were assessed for 120 days as to stability of the ascorbic acid and anthocyanins. The ascorbic acid content in nectar stored under light did not differ statistically from that protected from it. It was found that this vitamin in nectar stored for 120 days at a chilled temperature presented good stability. Concerning the anthocyanins, room temperature contributed negatively bringing about a more accelerated degradation, yet, exposure to light had no effect. According to trial conditions used in the present study, it was concluded that the light factor had little influence on the ascorbic acid and anthocyanins in the camu-camu nectar and that the temperature of storing it in the open shows it had a negative factor on the stability of these pigments.

Melhoria do rendimento e do processo de obtenção da bebida alcoólica de pupunha (Bactris gasipaes Kunth)

Pejibaye (Bactris gasipaes Kunth) fruits and natural fermentation are used by Amazonian natives to produce a thick drink called caicuma. The beverage presents high turbidity because of numerous pulp fragments of various sizes. A study done at the National Institute of Amazon Research showed that enzymatic starch hydrolysis, fermentation by Saccharomyces cerevisiae and filtration transformed caicuma into a highly acceptable drink. The experiment was carried out with the aim of increasing beverage volume yield and process efficiency by increasing the water:pulp ratio of the mash and eliminating the starch enzymatic hydrolysis, respectively. Raw and cooked pejibaye fruits were characterized in terms of their chemical properties. The mash was prepared with pejibaye pulp (previously cooked and autoclaved) and sucrose syrup. After Saccharomyces cerevisiae inoculation, the fermentation process was monitored (every 24 hours) during seven days by physical-chemical analysis. The beverage obtained was analyzed chemically, and, after sweetening, was submitted to a sensory evaluation panel. The cooked and autoclaved fruits presented partially hydrolyzed starch. Fermentation evolution was followed by sugar consumption, and alcohol and acid production. The beverage obtained showed high yield (about 60%), ideal alcoholic content (12.1%, v/v), characteristic color of the fruit, clearness, pleasant flavor and high acceptability (81.9%). The fermentation process without enzymatic hydrolysis of pejibaye starch and increased beverage volume did not affect the good quality and acceptability of the pejibaye beverage. The increased water:pulp ratio of the mash formulation contributed to the high beverage yield.