Quality of 'Delta Valencia' orange grown in semiarid climate and stored under refrigeration after coating with wax

The effects of carnauba-based wax on the quality of 'Delta Valencia' orange produced in Ceará state, Brazil, were studied. The fruits were coated with carnauba-based wax and refrigerated (7 ± 2 ºC and 85 ± 2% R.H.) for 28 days. The quality attribute parameters assessed were weight loss, peel color (brightness, hue angle, and chromaticity), peel moisture, pH, soluble solids (SS), titratable acidity (TA), SS/TA ratio, ascorbic acid, total soluble sugars, reducing sugars, yellow flavonoids, and polyphenols. The results showed that 'Delta Valencia' oranges grown in the dry climate of Ceará state has excellent quality. The coated fruits lost mass at a lower rate than the the control fruits. No significant loss of soluble solids, titratable acidity, pH, and SS/TA ratio was observed, while ascorbic acid, soluble sugars, reducing sugars, yellow flavonoids, and polyphenols increased during storage in both the coated and control fruits. Carnauba-based wax coated fruits showed no signal of dehydration keeping their shiny green peel up to the end of the storage. The use of coating was crucial for the maintenance of visual quality by reducing mass loss, as well as keeping peel moisture.

Effect of treatment with adsorbent resin on the volatile profile and physicochemical characteristics of clarified cashew apple juice

Increased preference for healthy and functional foods could be an opportunity to increase the consumption of clarified cashew apple juice. Given its level of fructose, glucose, and vitamin C, it can be used as a base in blends. However, its characteristic odor can interfere with the acceptance of these formulations, especially by consumers who are not familiar with cashew aroma. The aim of this study was to evaluate the effect of treatment with macroporous resins (FPA54, FPX66, XAD761, and XAD4) on the volatile profile and physicochemical characteristics of clarified cashew apple juice. After the treatment with the resins, the volatile profile was evaluated using solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS). The physicochemical analyses performed were: pH, soluble solids (ºBrix), total titrable acidity, reducing sugars, and vitamin C. Gas chromatography analyses showed that XAD4 and FPX66 led to a reduction of the initial amount of volatile compounds to 14.05% and 15.72%, respectively. These two resins also did not affect the physicochemical characteristics of the clarified cashew apple juice.

Evaluation of the PetrifilmTM and TEMPO® systems and the conventional method for counting microorganisms in pasteurized milk

New microbiological methods have been developed and commercialized, but their performance must be guaranteed. The aim of the present study was to evaluate the PetrifilmTM and TEMPO® systems compared to the conventional method for counting microorganisms in pasteurized milk. A total of 141 samples of pasteurized milk were analyzed by counting mesophilic aerobic, Coliforms at 35 ºC, Coliforms at 45 ºC, and Escherichia coli microorganisms. High correlation was found between the methods for counting Coliforms at 35 ºC, but low correlation was found for counting mesophilic aerobic, Coliforms at 45 ºC, and Escherichia coli. No significant statistical difference was found among the three methods for counting Coliforms at 35 ºC; however, the mean counts of mesophilic aerobic, Coliforms at 45 ºC, and Escherichia coli showed significant statistical difference. PetrifilmTM and TEMPO® systems had satisfactory results for Coliforms at 35 ºC in pasteurized milk but low performance for mesophilic aerobic, Coliforms at 45 ºC and Escherichia coli.

Carotenoid production by Rhodotorula rubra cultivated in sugarcane juice, molasses, and syrup

The Rhodotorularubra biomass and carotenoids production was evaluated in sugarcane juice, molasses, and syrup based media. The effects of media supplementation with urea- nitrogen or the commercial nutrient called Nitrofos KL was also verified. The experimental design used was a completely randomized factorial with 3 substrates (juice, molasses, and syrup) and three supplementations (control, urea, and Nitrofos KL). The results were submitted to variance analysis and Tukey test at 5% probability. The highest production of yeast dry mass was obtained with molasses media supplemented with urea or Nitrofos KL (15.09 and 14.87 g/L respectively). The intracellular carotenoid production was high in the media without supplementation (0.329 mg/g). The best growth medium for the volumetric production was molasses (2.74 mg/L), while those supplemented with urea and Nitrofos KL produced 2.55 and 2.32 mg/L, respectively. The major carotenoids produced were torulene, torularhodin, and β-carotene. The lowest carbohydrate consumption was observed in the sugarcane juice medium without supplementation, while the highest consumption was observed in the urea based supplementation medium.

Characterization and effect of clarified araçá (Psidium guineenses Sw.) juice on postprandial glycemia in healthy subjects

Brazilian native fruits are excellent sources of bioactive compounds of phenolic nature. Some of these compounds are able to inhibit carbohydrate- metabolizing enzymes (in vitro), α-amylase and α-glucosidase, delaying carbohydrate digestion. This study aimed to evaluate the effect of clarified araçá (Psidium guineenses Sw.) juice on postprandial glycemia in humans after consumption of 25 g of available carbohydrates (approximately 50 g of white bread) and characterize the phenolic compounds and in vitro antioxidant capacity of araçá juice and pulp. The results showed that the clarified juice had a positive effect on postprandial glycemia reducing the total amount of glucose absorbed, lengthening the time to reach maximum blood glucose concentration, reducing glucose incremental velocity, and decreasing glucose incremental percentage. Both frozen pulp and clarified juice had high amounts of phenolic compounds, antioxidant capacity, and proanthocyanidins, among which oligomers (monomers to tetramers), pentamers, hexamers, heptamers, octamers, nonamers, decamers, and polymers were detected, and they are probably associated with in vivo effects.

Study of the enthalpy-entropy mechanism from water sorption of orange seeds (C. sinensis cv. Brazilian) for the use of agro-industrial residues as a possible source of vegetable oil production

Orange seeds are a promising agroindustry-waste which can be implemented in the extraction and production of vegetable oil. The relationship between moisture content and water activity provides useful information for the processing and storage of this waste item. The aim of this study was to determine the mechanism of water sorption enthalpy-entropy of orange seeds (C. sinensis cv. Brazilians) according to the moisture content. Therefore, desorption isotherms were determined at five different temperature (30, 40, 50, 60, and 70 ºC) under a wide range of moisture content (0.005-0.057 kg kg-1 d.b.) and water activity (0.02-0.756). Theoretical and empirical models were used for modeling the desorption isotherms. An analytical solution of the Clausius-Clapeyron equation was proposed to compute the isosteric heat of sorption, the differential entropy, and Gibbs free energy using the Oswin model when the effect of temperature on the hygroscopic equilibrium was considered.

Development and optimization of a HPLC-RI method for the determination of major sugars in apple juice and evaluation of the effect of the ripening stage

The sugars in apple juice prove its authenticity and its sensory and nutritional properties. The aim of this study was to develop and validate a simple analytical method using high performance liquid chromatography with refractive index detection (HPLC-RI) to determinate and quantify the sugars sucrose, D-glucose, D-fructose, and D-sorbitol polyol in apple juices, as well as to analyze the juices from the Fuji suprema and Lis Gala cultivars at three ripening stages. The analytical performance parameters evaluated indicated that the method was specific for the compounds analyzed, and the linearity of the calibration curves of sugars showed high correlation coefficients (close to 1.0). The limits of detection and quantification are consistent with recommendations available in the literature for this type of matrix. Sample preparation is simple and generates small amount of residues. Over 70% of the sugars were determined in the juices of apples at the pre-ripe stage, with an increase during senescence. This method is applicable for the determination of sugars in juices and evaluation of apple ripening.

Use of Moringa oleífera Lamarck leaf extract as sugarcane juice clarifier: effects on clarifed juice and sugar

The objective of this study was to evaluate the effect of Moringa oleifera Lam. leaf extract on the sedimentation of impurities in the treatment of sugarcane juice and the effects on sugar quality and on the clarified juice. The experimental design used was a 4x2 factorial arrangement with four replications. The main treatments performed included the extracted original sugarcane juice, the synthetic polyelectrolyte (Flomex 9076), the leaf extract, and a control. The secondary treatments consisted of the sugarcane varieties RB92579 and RB867515. The clarification process used was simple defecation, in which the flocculating agents and the juice, limed and heated, were poured simultaneously into a decanter. The microbiological and chemico-technological characteristics of the extracted and clarified juices were evaluated. The clarified juice was concentrated up to 60° Brix (syrup) and subjected to boiling in a pilot pan using seeds to perform the graining: The sugar was recovered by centrifugation and analyzed for microbiological and chemico-technological characteristics. It was concluded that the use of the Moringa oleifera Lam. leaves extract resulted in a better quality of clarified juice and sugar.

Crossflow microfiltration of sugarcane juice: effects of processing conditions and juice quality

Sugarcane juice with passion fruit pulp was clarified using microfiltration under different T (temperature), P (pressure), and V (tangential velocity). The effects of these processing parameters were evaluated applying a rotational central composite experimental design (RCCD) and response surface methodology (RSM). The tests were performed at a filtration pilot plant using a polyamide hollow-fiber membrane with an average pore diameter of 0.4 µm and filtration area of 0.723 m². In addition, the resistances to the permeate flux during the microfiltration were investigated according to the series resistance. The final permeate flux ranged from 7.05 to 17.84 L·h- 1·m- 2. There was a rapid decline in flux (50%) in the initial stages of microfiltration. T and V were the major variables responsible for the flux increase. The concentration polarization showed the greatest influence on the flux decline, and highest values for the flux decline rate (λ) were found when low pressures were used. In the clarified juice there was a reduction in the contents of total solids, proteins, vitamin C, and acidity, while the soluble solids, pH, and ash contents did not change. Finally, membrane process could produce high quality filtered sugarcane juice with substantial flux and increased luminosity improving organoleptical properties.

Orange fiber as a novel fat replacer in lemon ice cream

Orange fiber was used as a novel fat replacer in light lemon ice cream. Nine ice cream formulations were compared: standard control ice cream (IC); ice cream with fiber (F1) from the peel, bagasse, and orange seed (ICA and ICB); ice cream with fiber (F2) from the orange peel alone (ICC and ICD); ice cream with fiber (F3) from the peel, bagasse, and orange seed pretreated with hydro-distillation (ICE and ICF); and ice cream with fiber (F4) from the orange peel pretreated with hydro-distillation (ICG and ICH).The orange fiber reduced the ice cream fat content (50 %) and the overrun ratio and increased the fiber content and the hardness, gumminess, and springiness values, but it did not affect the adhesiveness and odor of the samples. The samples with 1.0 % of orange fiber showed low melting rate values than those of the control ice cream. The overall acceptance of the ice cream with 1.0 % of pre-treated orange peel fiber did not differ from that of the control ice cream (80 %). The orange fiber proved a promising food ingredient since it can be used to decrease the fat content and increase bioactive compounds content, such as fiber and carotenoids.

Application of enzymatic preparations to produce araçá pulp and juice

In the present study, the effect of pectinases on the production of pulp and juice of araçá and the presence of bioactive compounds were evaluated. An enzyme extract (EE) produced by Aspergillus niger LB-02-SF in solid state fermentation and the commercial enzyme Ultrazym®AFP-L were used in this study. After enzyme treatment with the EE preparation, the extraction yield increased by 23.1% and viscosity decreased by 42.8%, during pulp maceration. During juice processing, there was an increase of 70.6% in clarification and a decrease of 72.87% in turbidity. Higher values of these parameters, 47.7, 69.0, 80.7, and 79.7%, respectively, were obtained using the Ultrazym®AFP-L, which also led to a significant increase in the polyphenol content, both in the pulp (24%) and in the juice (28%), with a less pronounced effect when the EE was applied (10 and 21%, respectively). The anthocyanins content in the araçá pulp increased after treatment with the commercial preparation (23%), and there was no significant increase with the use of EE. The use of Ultrazym®AFP-L increased the β-carotene content by 29.4% in the fruit pulp, while the treatment with EE did not result in significant changes compared with those of the juice and pulp controls.

Influence of agro-ecological production areas on antioxidant activity, reducing sugar content, and selected phytonutrients of orange-fleshed sweet potato cultivars

Sweet potato is an important staple, and it is mainly known for its contribution of β-carotene in human diet. The effects of cultivar and habitat on this pigment and other nutritional characteristics of the crop still require investigation. In this study, three locally bred cultivars of sweet potato, two of which are orange-fleshed, were grown in three different agro-ecological areas to determine soluble sugar content, β-carotene, and total antioxidants of roots. In addition antioxidant activity, total carotenoids, and chlorophyll content were determined in edible leaves. Reducing sugars, β-carotene, total antioxidants capacity, total carotenoids, and chlorophyll content were significantly affected by environmental conditions. The location at lower altitude and closer to the coastline showed high evapotranspiration, thus reducing sugar content, antioxidant activity, and phytonutrients in both storage roots and leaves. Absence of water stress in agro-ecological locations further inland and at higher altitudes was associated with an increase in these compounds. Free radical scavenging activity of DPPH was higher in the storage roots (610.49 µmoles TE/100g) than in the leaves (426.06 µmoles TE/100g); nevertheless, opposite results were found for the ferric ion reducing activity (FRAP). The deep orange-fleshed cultivar A45 contained high β-carotene (15 mg/100g), which is enough to meet RDA for vitamin A. There is evidence of agro-ecological effect on sweet potato nutritional value.

Influence of distillation time and sample mass on sulfur dioxide analysis in passion fruit juice through Monier-Williams method

AbstractThis study aimed to evaluate the effect of the distillation time and the sample mass on the total SO2 content in integral passion fruit juice (Passiflora sp). For the SO2 analysis, a modified version of the Monier-Williams method was used. In this experiment, the distillation time and the sample mass were reduced to half of the values proposed in the original method. The analyses were performed in triplicate for each distilling time x sample mass binomial, making a total of 12 tests, which were performed on the same day. The significance of the effects of the different distillation times and sample mass were evaluated by applying one-factor analysis of variance (ANOVA). For a 95% confidence limit, it was found that the proposed amendments to the distillation time, sample mass, and the interaction between distilling time x sample mass were not significant (p > 0.05) in determining the SO2 content in passion fruit juice. In view of the results that were obtained it was concluded that for integral passion fruit juice it was possible to reduce the distillation time and the sample mass in determining the SO2 content by the Monier-Williams method without affecting the result.

Cytotoxic and genotoxic potential of powdered juices

Abstract Powdered juices are widely consumed by the population especially because of their convenient preparation, availability in various fruit flavors and low cost when compared to other industrialized beverages. They have complex formulation, consisting of several classes of food additives. However, there are no scientific studies on the toxicity of these foods. Thus, this study evaluated the toxicity at the cellular level of industrialized powdered juices of orange and guava flavors of three different food companies. This analysis was made using root meristem cells of Allium cepa L., at the exposure times of 24 and 48 hours, and two concentrations, 30 g/1000 mL, considered ideal for consumption according to the label of the products, and 30 g/500 mL. Both flavors of juices, of the three companies, in both concentrations and the two exposure times promoted significant antiproliferative effect to root meristem cells and caused a statistically significant number of mitotic spindle changes and micronuclei in cells of the test system used. Therefore, under the studied conditions, all the samples of juice powder exhibited cytotoxic and genotoxic potential.

Effect of ultrasound treatment on quality and microbial load of carrot juice

Effect of ultrasound treatment on carrot juice was investigated through measuring pH, electrical conductivity, viscosity, visual color, total soluble solids, total sugars, total carotenoids, ascorbic acid contents and microbial load. No significant effect (p>0.05) of ultrasound treatment on pH of carrot juice was observed. Electrical conductivity, viscosity and color values gradually increased (p<0.05) with treatment time increase. Total soluble solids, total sugars, total carotenoids and ascorbic acid contents of carrot juice were significantly improved (p<0.05) due to ultrasound treatment. Moreover, significant decrease (p<0.05) in microbial load of sonicated carrot juice was observed. Results from present study suggested that ultrasound treatment could improve quality and safety of carrot juice.