Amazonian palm tree fruits: From nutritional value to diversity of new food products.

The rapid growth of the world population has increased the demand for new food sources, constituting a major challenge concerning the maximum use of existing food resources. The fruits of Amazonian palm trees have excellent nutritional composition and bioactive compounds. This review highlights four fruits of Amazonian palm trees that are still little explored by the food industry: açai (Euterpe oleracea), pupunha (Bactris gasipaes), buriti (Mauritia flexuosa), and tucumã (Astrocaryum aculeatum). This paper aims to inspire new ideas for researching and developing products for the food industry. It also explores the impacts of Amazonian palm fruits on health, highlighting their role in disease prevention through their nutritional effects.

Encapsulation of bioactive compounds extracted from plants of genus Hibiscus: A review of selected techniques and applications.

The genus Hibiscus includes more than 250 species, and many studies showed that these plants contain bioactive compounds with technological potential to be used in the development of functional foods. However, the instability of these compounds during typical food processing conditions, such as exposure to high temperatures, pH changes and presence of light and oxygen have stimulated the use of encapsulation techniques to increase their stability and applicability. Among the existing Hibiscus species, only H. sabdariffa, H. cannabinus, and H. acetosella have been investigated in encapsulation studies, being spray drying the most common method approached. Considering the high technological potential offered by the incorporation of encapsulated bioactive compounds from plants of the genus Hibiscus in food formulations, this review discusses key information of selected encapsulation techniques, which represents promising alternatives to increase food systems' stability and stimulate the design of new functional foods. Relevant gaps in the literature were also noticed, mainly the lack of systematic studies regarding the composition of bioactive compounds after encapsulation, instead of total determinations, and biological activities in different analytical systems, such as antioxidant, antimicrobial and anti-inflammatory properties as well as bioaccessibility and bioavailability.

Peach palm flour: production, hygroscopic behaviour and application in cookies.

In this work, two types of flour from peach palm fruits (Bactris gasipaes) were prepared to be used to produce cookies: one with the whole fruit (pulp + peel) and another one with only the pulp. Analyses of proximate composition, physicochemical and hygroscopic behaviour were carried out in both flour, as well as sensory analysis of the produced cookies. Both the types of flour did not differ statistically in total lipids, total carbohydrates and ashes (p > 0.05). Among the mathematical models tested for the prediction of the hygroscopic behaviour of both flour, Halsey model showed the best fit to the experimental data (R2 = 0.99 and P<10%). The cookies produced with both types of peach palm flour presented low moisture (4.9-6.2%), high lipid content (25.56-26.37%) and total carbohydrates (59.10-61.84%), resulting in a product with high total energetic value (501.8-502.8 kcal/100 g). Based on the results of acceptance test, both cookie formulations presented good sensory acceptance (>70%). The purchase intention inquiry showed that the cookie prepared with the whole fruit flour presented the highest percentage of purchase intention (85%), which demonstrate that the use of peach palm peels in the development of new food products represent an excellent alternative for the use of by-products.

Influence of spontaneous fermentation of manipueira on bioactive amine and carotenoid profiles during tucupi production.

Tucupi is a kind of broth that is common to the Amazonian region of Brazil, which is produced after the spontaneous fermentation and boiling of manipueira, a liquid by-product extracted from cassava roots during cassava flour production. The bioactive amines formation and their alterations during tucupi processing were investigated for the first time. In addition, the physicochemical changes, instrumental color parameters and carotenoid profile were monitored during tucupi production. Regarding the changes on the profile of carotenoids, all-trans-ß-carotene was the major carotenoid, followed by its 9- and 13-cis isomers, and this profile was not altered throughout the process. Spermidine (polyamine), putrescine, tyramine and histamine (biogenic amines) were the bioactive amines identified during the tucupi production process, but at low levels (0.76-7.24 mg/L). Principal Component Analysis suggested three distinct stages during tucupi production: the first stage was characterized by the manipueira up to 12 h of fermentation with the highest values of pH, total and reducing sugars, and total starch; the second stage refers to the end of the fermentation process (16 to 24 h), in which biogenic amines (histamine and tyramine) were produced; and the third stage was characterized by the final product (tucupi), with the highest values of total acidity, soluble solids, polyamines and tyramine. Therefore, the results suggest the need of an accurate control of the fermentation of the manipueira to avoid or minimize the formation of biogenic amines.

Application of pulsed-vacuum on the salt impregnation process of pirarucu fillet.

The influence of the pulsed-vacuum impregnation (PVI) and periodic pulsed-vacuum impregnation (PPVI), and the temperature, on the salting process of pirarucu fillet was studied. For this, the dorsal region of the fish in the slab-shaped (60 mm × 20 mm × 5 mm) and sodium chloride solution (30 g/100 g NaCl) were used. The process was conducted at different temperatures (10 °C - 40 °C) and the following pulsed-vacuum conditions: initial vacuum pulse (5 min at 10 kPa) and alternating periods of vacuum pulse (5 min at 10 kPa) and atmospheric pressure (101 kPa) for 5 min, 10 min and 15 min intermittently. The solid gain (SG) in the fillet was more pronounced in the first two hours of the salting process. The increase of salt content in the product (0.33 ±â€¯0.02 to 0.43 ±â€¯0.04 g/g db) promoted the gradual reduction of moisture (72.99 ±â€¯1.27 to 57.1 ±â€¯2.4 g/100 g) and water activity (1.00 ±â€¯0.03 to 0.78 ±â€¯0.05). PVI and PPVI processes can be used efficiently at room temperature or under refrigeration in the salting process of pirarucu fillet. On the other hand, at higher temperatures (>30 °C), the effect of temperature prevails over the effect of vacuum. Peleg model satisfactorily explains the salting kinetics of the pirarucu fillet.

Optimization of spray drying process parameters for tucupi powder using the response surface methodology.

A completely randomized 23 factorial experimental design was used to optimize the process parameters for obtaining tucupi powder through spray drying. The effects of the process variables [inlet air temperature (IT), feed flow rate (FR), and maltodextrin concentration (MD)] on the product properties [moisture, water activity (aw), hygroscopicity, water absorption index (WAI), water solubility index (WSI), total color difference (ΔE*), and ß-carotene content] were studied using the response surface methodology (RSM) and linear perturbation plot. In addition, scanning electron microscopy (SEM) images were obtained of the product. According to ANOVA and the regression coefficients (R2 > 0.90), the RSM models were significant and IT was the variable with the greatest impact on most of the responses. SEM shows that the powders obtained with higher IT and MD and lower FR were more uniform, with smooth and intact surfaces. The optimal conditions estimated for the process were IT at 214 °C, FR at 8.67 mL/min, and MD at 27%. Under those conditions, the product's minimum values of moisture (9.56 g/100 g), aw (0.101), hygroscopicity (37.45% d.b.), and ΔE* (17.05) and maximum values of WAI (6.68 g/g d.b.), WSI (84.77%), and ß-carotene (13.72 µg/g) were estimated.

Combined osmotic dehydration and drying process of pirarucu (Arapaima gigas) fillets.

The osmotic dehydration (OD) and complementary drying of pirarucu (Arapaima gigas) fillets were studied. Pieces of the dorsal portion of pirarucu (60 mm × 20 mm × 10 mm) underwent OD in a binary solution (NaCl-water) with the application of vacuum pulse following a central rotatable composite design. The effect of the following process variables was assessed: temperature (20-40 °C), osmotic solution concentration (15-25% NaCl), and vacuum pulse pressure (7-101 kPa) on water loss (WL), solid gain (SG), and water activity (aw). OD kinetics was obtained and the Peleg model was fitted to WL and SG data. The osmotically dehydrated pirarucu was dried (40-70 °C) in a fixed-bed dryer and mathematical models were fitted to the drying data. The optimal operational condition for the OD process was 35 °C, solution with 25% NaCl, and atmospheric pressure, which yielded WL of 14.87 ± 1.46%, SG of 8.56 ± 0.45%, and aw of 0.87 ± 0.02. The Peleg model efficiently predicted the WL and SG kinetics. The increase in the water loss in drying was more evident at low temperatures (40-50 °C) with effective diffusivity ranging from 10.85 × 10-9 to 12.30 × 10-9 m2/s. The Midilli and Page models efficiently predicted the drying kinetics.

Anthocyanins of Jambolão (Syzygium cumini): Extraction and pH-Dependent Color Changes.

Jambolão fruits are promising sources of anthocyanins, and in this study, the jambolão fruit from the Brazilian Amazonian region was characterized and the efficiency of six ethanol-based solutions to extract anthocyanins was determined. Moreover, the color changes of anthocyanin extracts, as influenced by different pH conditions (pH from 1.0 to 8.0), were evaluated. The fruits exhibited high contents of total anthocyanins (296 mg/100 g) and the CIELAB parameters characterized jambolão as a purple-red colored fruit (a* = 20.30, b* = -4.17, and hab∘= 348.39). Among the six different ethanol-based solutions, ethanol 95% with 1% of HCl (v/v) was the most efficient solution to extract anthocyanins from jambolão fruits. Furthermore, the CIELAB parameters were characterized as useful tool to monitor the color changes of anthocyanins of jambolão over the tested pH range. Therefore, jambolão fruits from Amazonian region have technological potential for the application by food, pharmaceutical, and cosmetic industries. PRACTICAL APPLICATION: Jambolão fruits are great source of anthocyanins and the incorporation of these natural pigments as food colorants is not only valuable to improve overall appearance, but it is also beneficial to human health. The production of natural extracts with high levels of anthocyanins from jambolão can be considered a very useful approach to the food, pharmaceutical and cosmetic industries.

Bioactive amines and phenolic compounds in cocoa beans are affected by fermentation.

Cocoa is the target of increased scientific research as it is one of the richest source of bioactive compounds. The formation of bioactive amines and their changes in cocoa beans during seven days of traditional fermentation was investigated for the first time. In addition, total phenolic compounds, anthocyanins contents and the scavenging capacity against ABTS radical were determined to monitor the fermentation process. Only two biogenic amines (tryptamine and tyramine) and two polyamines (spermidine and spermine) were detected in cocoa beans during fermentation. Fermentation was characterized by three stages: i) high levels of tryptamine, phenolics, and scavenging capacity; ii) high contents of spermine, total biogenic amines and total polyamines; and iii) the highest spermidine levels and total acidity, but the lowest total phenolic compounds and anthocyanins contents. The scavenging capacity of cocoa beans during fermentation correlated with total phenolic compounds and anthocyanins contents.

Influence of the process parameters on osmotic dehydration of mapara (Hypophthalmus edentatus) fillet.

The effects of temperature, time, pressure and brine concentration were assessed during osmotic dehydration (OD) of H. edentatus fillet. The response surface methodology (RSM) showed that using vacuum during the OD process did not cause a statistically significant change (p > 0.05) on the water loss (WL), solid gain (SG) and water activity (aw). The other factors showed a statistically significant effect (p ≤ 0.05) on at least one of these responses. Through RSM, the following condition could be defined for the OD process: brine concentration at 25 % NaCl, 25 °C, 120 min and atmospheric pressure. The Azuara model was shown to be effective in predicting the WL and SG kinetics during the OD process. The simplified solution of Fick's second law of diffusion for a slab geometry was used to calculate the average values of apparent diffusion coefficient (Deff), namely 4.73 × 10(-10) m(2)/s for WL and 1.33 × 10(-9) m(2)/s for SG.