Concentration of pineapple juice by reverse osmosis: physicochemical characteristics and consumer acceptance

Reverse osmosis has been used for the concentration of fruit juices with promising considering the quality of the obtained products. The objective of this study was to concentrate single strength pineapple juice by reverse osmosis. The concentration was carried out with polyamide composite membranes in a 0.65 m² plate and frame module at 60 bar transmembrane pressure at 20 °C. The permeate flux was 17 L.hm-2. The total soluble solid content of the juice increased from 11 to 31 °Brix corresponding to a Volumetric Concentration Factor (VCF) of 2.9. The concentration of soluble solids, total solids, and total acidity increased proportionally to FCV. The concentrated juice and three commercial concentrated pineapple juices were evaluated regarding preference and purchase intention by 79 pineapple juice consumers. The concentrated juice by reverse osmosis was the preferred among consumers. It can be concluded that this process may be considered an alternative to the pre-concentration of fruit juices.

Effect of genotype, finishing system, and sex on physiochemical characteristics of goat meat

Seventy-eight kids of both sexes and five genotypes were used: Alpine, ½ Boer + ½ Alpine (½ BA), ¾ Boer + ¼ Alpine, ½ Anglo-nubian + ½ Alpine and "tricross" (½ Anglo-nubian + ¼ Boer + ¼ Alpine) with initial average weight of 14.1 ± 2.5. The objective was to evaluate the effect of genotype, finishing system, and sex on the physiochemical characteristics of goat meat. Finishing systems were: ST1 - kid + dam in pasture and ST2 - weaned kid and feedlot. Kids in ST1 were kept in an area with Panicum maximum cv. Tanzania, and after grazing, water and mineral salt/mix were fed ad libitum to the animals. The animals in ST2 were confined in collective pens distributed according to genotypes and received diet with 16% CP and 73% TDN. The values of pH, a* (red content), Cooking Loss (CL), and Ether Extract (EE) percentage were influenced by genotype. Values for red content (a*) and L* (brightness), CL and percentages of moisture, protein, EE, and ash were influenced by the finishing system. Longissimus dorsi muscle from animals ½ BA exhibited better physiochemical characteristics. For greater tenderness and higher percentages of fat, consumers should choose female kid goat meat.

Starch edible coating of papaya: effect on sensory characteristics

The coating of papayas with Cassava Starch (CS) and carboxymethyl starch (CMS) is an alternative to extend the shelf life of these fruits. This study evaluated the effect of the three different levels of CS and CMS (1, 3, and 5%) on sensory characteristics of papayas during storage. Nine selected and trained assessors evaluated 13 sensory attributes using the Multiple Comparison Test. The appearance and flavor attributes of the papayas treated with CS and CMS were compared to the control or reference sample (R - fruit without coating) using a nine-point scale, which varied from 1: less intense than R; 5: equal to R; 9: more intense than R. The samples were coded with three digit numbers and evaluated with repetition by a panel of assessors. In general, appearance was more affected by the coatings than flavor. Fruits coated with 3 and 5% of both coatings kept the green color longer than the other coating’s concentrations, and at 5% the color of the fruits was less uniform on the last evaluation day. The 3 and 5% CS coating gave greater brightness to the fruits. 5% CMS favored the presence of fungi and damaged the fruit surface at the 14th day of storage. The CS coating at 5% presented peeled surface during all experimental time. Changes in fruits’ flavor were perceived at the 12th and 14th days of storage. A less characteristic flavor and a bitter taste were noticed in the fruits coated with CS and CMS at 5% at the 12th day of storage.

Analytical characteristics and discrimination of Brazilian commercial grape juice, nectar, and beverage

The production and commercialization of Brazilian grape juice is increasing annually, mainly due to its typicality, quality, and nutritional value. The present research was carried out in view of the great significance of Brazilian grape juice for the grape and wine industry. The purpose of this study, therefore, was to assess its composition as well as the discrimination between grape juice and other beverages. Twenty four samples of whole, sweetened, and reprocessed grape juices, grape nectar, and grape beverage were evaluated. Classical variables were analyzed by means of physicochemical methods; tartaric and malic acids, by HPLC; methanol, by gas chromatography; minerals, by atomic absorption spectrophotometry. These products were discriminated by the Principal Component Analysis (PCA). Results show that whole and sweetened grape juices were discriminated from other grape products because they featured higher values of total soluble solids, tartaric and malic acids, most minerals, phenolic compounds, and K/Na ratio, whereas grape nectar and grape beverage presented higher values of ºBrix/titratable acidity ratio. Reprocessed juice was discriminated due to its higher concentrations of Li and Na and lower hue.

Physicochemical characteristics and functional properties of vitabosa (mucuna deeringiana) and soybean (glycine max)

Physicochemical characteristics and functional properties of vitabosa flour (Mucuna deeringiana) and soybean flour (Glycine max) were determined. Oil absorption capacity was higher in vitabosa. Water absorption capacity was higher in soy and it was affected by the change in the ionic strength of the medium. Emulsifying Activity (EA) decreased with increasing concentration of flour, while Emulsifying Stability (ES) showed an increased. EA and ES of flours have more ionic strength in the range between 0.0 and 0.4 M, but it is reduced afterwards with the higher concentration of NaCl. Foaming stability varied with the concentration of flour solution reaching maximum values of 39 and 33% for vitabosa and soybean, respectively at 10% flour concentration.Vitabosa had the best foaming capacity (56% to 0.6 M) compared with soybeans (47% to 0.4 M). Maximum capacity of gelation was observed in vitabosa at 10% flour concentration. Increases in ionic strength of the flour solution, at low salt concentrations (<0.4 M), improved the gelation of flours.

Not any type of rice performs equally to improve lactose-induced diarrhea characteristics in rats: is amylose an antidiarrheal factor?

The effectiveness of different types of rice in relation to their ability to accelerate diarrhea recovering was evaluated in a rat model of osmotic diarrhea (OD). Animals (90-100 g) received protein free diet until reaching up to 20% weight loss, followed by lactose rich diet (LRD) to induce osmotic diarrhea. Rats presenting osmotic diarrhea were divided into 4 groups, which received lactose rich diet for 4 days from 8 am to 8 pm, and one of three experimental products containing 6% rice flour differing in amylose content during the night: high (HA), intermediate (IA), and low (LA). A group fed stock diet containing equivalent amount of lactose was taken as control and allowed to recover spontaneously. Amylose and viscosity (cp at 25 °C, 10 rpm) of final products were determined. Effectiveness was expressed as the ratio between percentages of normal vs. diarrheic stools during the treatment. Fecal characteristics in this rat model improved only as result of feeding high amylose content (HA) type of rice. In this experimental model of osmotic diarrhea in young rats, the antidiarrheal effects of rice were strongly dependent on the type of diet used and appear to be related to its amylose content.

Effect of harvest at different times of day on the physical and chemical characteristics of vegetable-type soybean

The objective of this study was to evaluate the effect of harvest at different times of day on the chemical and physical characteristics of vegetable-type soybean BRS 267 cultivar, harvested at the R6 stage (seed development) and to compare it with that on the grains harvested at the R8 stage (maturation). The pods of the BRS 267 cultivar were harvested at the R6 stage (at 8:00 AM, 12:00 AM, and 6:00 PM), the color parameters were evaluated, and the grains were analyzed for chemical composition, activity inhibitor trypsin, phytic acid content, starch, sugars, fatty acids, and isoflavones. No differences were observed among the different harvest times in terms of the chemical constituents of vegetable-type soybean BRS 267 cultivar harvested at the R6 stage. Isoflavones content did not change with different harvest times, and the aglycone forms (daidzein, glycitein, and genistein) were found in smaller quantities at the R6 stage compared to the R8 stage. The color of the pods of soybean BRS 267 cultivar, harvested at the R6 stage did not change with different harvest times. The grains harvested at the R6 stage had lower protein content, phytic acid, and sucrose and higher levels of lipids, carbohydrates, starch, glucose, fructose, stachyose, and linolenic acids than those collected at the R8 stage. The different times of harvest did not affect the quality of the vegetable-type soybean BRS 267 cultivar harvested at stage R6. Nevertheless, it is recommended to harvest in the morning, when the temperature is milder, like other vegetables, to facilitate and optimize its marketing and in natura consumption.

Effect of pre and post-slaughter processes on meat characteristics of Santa Ines ewes discarded due to age

The effects of body condition recovery (BC), carcass electrical stimulation (ES), aging time (AT 7 - 14 days), and calcium chloride injection on the meat characteristics of Santa Inês ewes (±5 years old) slaughtered immediately after weaning or after the body condition recovery period were studied. The carcass temperature, pH, shear force (SF), cooking loss (CL), meat color (L*, a*, b*), and meat tenderness were evaluated. A completely randomized design in a 2 × 2 × 2 × 3 (BC × ES × CaCl2 × AT) factorial arrangement was used, and the sensory tenderness data were analyzed using the table of Minimum Number of Correct Answers for the Duo-Trio test. The body condition recovery reduces the shear force in 8%, increasing their tenderness. Electrical stimulation reduced the shear force (24%) and did not change the other parameters. The aging time (7 or 14 days) decreased the shear force (18-26%), effect that was enhanced by electrical stimulation, and it darkened the meat reducing lightness (L*) and increasing yellowness (b*). The treatment with CaCl2 was the most effective in tenderizing meat by reducing the shear force ( 35%); increasing the cooking loss (4.5%); and increasing L* and b* lightening the meat. The sensory evaluation of tenderness corroborates the findings of the experimental evaluation regarding the effect of the treatment with CaCl2 on the meat quality improvement. It was concluded that the treatments improve meat characteristics achieving better results when applied together.

Physical, chemical, technological and sensory characteristics of Frankfurter type sausage containing okara flour

The addition of okara flour to an emulsified meat product (Frankfurter type sausage) was evaluated based on the physical, chemical, technological, and sensory characteristics of the final product. Okara, residue from soymilk production, was provided by two soymilk producing companies whose production systems were based on the hot disintegration of the decorticated (company B) or undecorticated (company A) soybeans. The okara was dehydrated using a flash dryer and then ground into flour (>420 µm). However, The okara flours A and B showed approximately the same amount of protein (35 and 40 g.100 g-1 dwb). However, the okara flour A presented higher values (p < 0.05) for all technological functional properties studied (emulsification capacity, emulsion stability, protein solubility, and water hold capacity) than those of okara flour B. The A and B okara flours were used in a frankfurter sausage formulation as substitution of 1.5% and 4% of meat. The results showed that the sausages containing okara flours A and B, as well as the control sausage, were accepted by the sensory panel. Moreover, there were no significant differences (p < 0.05) in the physical (color, objective texture, and emulsion stability) and chemical (pH and proximate composition) measurements of the sausages with and without the okara flour.

Meat quality characteristics of exotic and SPRD crossbred goats from the semiarid region

Thirty-two intact male goats from four genetic groups (eight pure-bred Boers, eight ¾ Boer + ¼ SPRD crossbreeds, eight ½ Boer + ½ SPRD crossbreeds, and eight ½ Anglo Nubian + ½ SPRD crossbreeds) were evaluated for meat quality. The goats were reared in confinement and slaughtered at the average live weight of 29 kg. Temperature and pH decrease in the longissimus dorsi muscle was determined for 24 hours, and analyses of colour, cooking loss, water-holding capacity, and sensory attributes were also performed. Genotype significantly (P < 0.05) influenced the confinement period; ½ Boer + ½ SPRD crossbreeds required the most time in confinement to reach the target weight, while the pure-bred Boers required the least time. Genotype also significantly influenced (P < 0.05) the weight loss due to cooking, shearing force, colour (intensity of yellowness and luminescence), and the sensory attributes of flavour, odour, and raw colour of the meat. The crossing of exotic Boer and Anglo Nubian breeds with the native SPRD resulted in a goat meat of high quality.

Genetic diversity and comparison of physicochemical and nutritional characteristics of six quinoa (Chenopodium quinoa willd.) genotypes cultivated in Chile

The present study was focused on the analysis of agronomical, nutritional, physicochemical, and antioxidant properties of six genetically different quinoa (Chenopodium quinoa Willd) genotypes cultivated in three distinctive geographical zones of Chile. Ancovinto and Cancosa genotypes from the northern Altiplano (19 ºS), Cáhuil and Faro from the central region (34 ºS), and Regalona and Villarica from the southern region (39 ºS) are representative of high genetic differentiation among the pooled samples, in particular between Altiplano and the central-southern groups. A Common-Garden Assay at 30 ºS showed significant differences among seed origins in all morphometric parameters and also in yields. Altiplano genotypes had larger panicule length but no seed production. A significant influence of the different quinoa genotypes on chemical composition and functional properties was also observed. Protein concentration ranged from 11.13 to 16.18 g.100 g-1 d.m., while total dietary fiber content ranged from 8.07-12.08 g.100 g-1 d.m., and both were the highest in Villarrica ecotype. An adequate balance of essential amino acids was also observed. Sucrose was the predominant sugar in all genotypes. Antioxidant activity was high in all genotypes, and it was highest in Faro genotype (79.58% inhibition).

Influence of xylanase addition on the characteristics of loaf bread prepared with white flour or whole grain wheat flour

The aim of this study was to verify the influence of the addition of the enzyme xylanase (four concentrations: 0, 4, 8, and 12 g.100 kg-1 flour) on the characteristics of loaf bread made with white wheat flour or whole grain wheat flour. Breads made from white flour and added with xylanase had higher specific volumes than those of the control sample (no enzyme); however, the specific volume did not differ significantly (p < 0.05) among the breads with different enzyme concentrations. All formulations made from whole grain wheat flour and added with xylanase also had specific volumes significantly higher than those of the control sample, and the highest value was found for the 8 g xylanase.100 kg-1 flour formulation. With respect to moisture content, the formulations with different enzyme concentrations showed small significant differences when compared to the control samples. In general, breads made with the addition of 8 g enzyme.100 kg-1 flour had the lowest firmness values, thus presenting the best technological characteristics.

Effect of starter culture and inulin addition on microbial viability, texture, and chemical characteristics of whole or skim milk Kefir

The effect of inulin addition and starters (Kefir grains or commercial starter culture) on the microbial viability, texture, and chemical characteristics of Kefir beverages prepared with whole or skim milk was evaluated during refrigerated storage. The type of starter did not influence microbial viability during the storage of the beverages, but the chemical and textural changes (decreases in pH, lactose concentration, and inulin and increased acidity, firmness, and syneresis) were more pronounced in the formulations fermented with grains than those fermented with the starter culture. The addition of inulin did not influence acidity or viability of lactic acid bacteria, but in general, its effect on the survival of acetic acid bacteria, Lactococcus and yeasts, firmness, and syneresis depended on the type of milk and starter culture used. Generally, the yeast, acetic acid bacteria, and Leuconostoc counts increased or remained unchanged, while the total population of lactic acid bacteria and Lactococcus were either reduced by 1 to 2 logs or remained unchanged during storage.

Studies of chemical and enzymatic characteristics of Yacon (Smallanthus sonchifolius) and its flours

Due to the importance of studies on yacon related to health, its in natura pulp, in natura peel, pulp flour, and peel flour were chemically analyzed in terms of its centesimal composition, specific minerals, total dietary fiber and fractions, pH, total soluble solids, total titratable acidity, tannins, oxalic acid, and nitrate. The polyphenoloxidase and peroxidase enzymatic activities were evaluated for in natura pulp and peel only. Yacon pulp and peel flour presented average yield of 7.94% and 10.86%, respectively. The in natura pulp presented a higher moisture and carboydrate content and lower lipid, protein, total dietary fiber, and ash than those of the peel flour. The same pattern was observed for pulp flour when compared to peel flour. The highest tannin, nitrate, and oxalic acid levels were found in the peel flour, 15,304.5 mg.kg-1, 1,578.3 mg.kg-1, and 7,925.0 mg.kg-1 (wet weight), respectively. The polyphenoloxidase and peroxidase enzymes presented higher enzymatic activity in the yacon peel. Based on the results obtained, it can be said that the yacon and its derivatives are important dietary carbohydrate and mineral sources and contain antinutritional substance contents lower than those harmful to health.

Physicochemical and microbiological characteristics of minimally processed 'Champagne' oranges (Citrus reticulata × Citrus sinensis) in different packgings

The objective of this study was to investigate the influence of the level of minimal processing and modified atmosphere on the quality of 'Champagne' orange stored under refrigeration. The fruits were subjected to the following processing: a) whole fruit without flavedo; b) whole fruit without flavedo and albedo; and c) segmented into wedges and packed as follows: uncoated packaging (control); polyethylene film; PVC film; gelatin-based edible films (3%); and polyesthyrene translucent plastic container with a lid. The minimally processed oranges were stored at 5 ± 1°C for 8 days and were subjected to physicochemical and microbiological analyses every two days. Greater weight loss occurred in fruits without flavedo and segmented, uncoated, and coated with the edible gelatin film During storage, there was a slight increase in Total Soluble Solids (TSS) for the treatments with greater weight loss and reduction in acidity and ascorbic acid, regardless of the packaging type. The microbial counts did not exceed the acceptable limits in the treatments; however, higher counts were observed at the end of storage. The minimally processed fruit packed in lidded polystyrene containers and polyethylene and PVC films kept their overall fresh visual appearance with a few physicochemical and microbiological changes up to the 8th day of storage.