Drying of sicilian lemon residue: influence of process variables on the evaluation of the dietary fiber produced

In this study, the effect of the process variables of the air-drying of Sicilian lemon residues on some technological properties of the fibers produced was studied. The determination and modeling of desorption isotherms were used to establish the equilibrium moisture content at 60, 75, and 90 °C using the static method with 8 saturated salt solutions. The best fit was obtained with BET and GAB models. The drying process was conducted in a vertical tray dryer and delineated according to a central composite experimental design (2²) using the following as factors: air velocity (0.5, 0.75 and 1 m/s) and temperature (60, 75, and 90 °C), and it presented a good fit to the exponential model (R² > 99.9%). The experimental design responses evaluated were the technological properties of the fibers: water-holding, oil-holding, and swelling capacity. Since these properties were present in high levels, the lemon residues could be used to increase content of fibers in foods resulting in the addition of nutritional benefits for the consumers.

Sensory evaluation and nutritional value of cakes prepared with whole flaxseed flour

The objective of this study was to evaluate the nutritional value, the oxidative stabilitiy, and consumer acceptance of cakes containing four different concentrations of flaxseed flour (5, 15, 30 and 45%) as partial replacement for wheat flour. The oxidative stability of polyunsaturated fatty acids was evaluated through the lipid peroxidation test (TBARS) in the flour and cakes. Linolenic acid was determined by gas chromatography as well as contents of protein, lipid, ash, and dietary fiber. Consumer acceptance was assessed using a structured hedonic scale of nine points. The oxidative stability of lipid flaxseeds was not affected by the heat treatment during flour processing and cake baking. Cakes made with 5, 15, and 30% of flaxseed flour, the most accepted by consumers, had dietary fiber levels ranging from 3.5 to 6.2 g and linolenic acid ranging from 445 to 2,500 mg.100 g-1 of the product. The cakes received claims of good and excellent source of dietary fiber and linolenic acid, respectively, both are bioactive compounds. The use of up to 30% of flaxseed flour in the preparation of cakes is a useful strategy to optimize the consumption of food rich in functional ingredients.

Effects of defatted amaranth (Amaranthus caudatus L.) snacks on lipid metabolism of patients with moderate hypercholesterolemia

We evaluated the effects of defatted amaranth (Amaranthus caudatus L.) snacks on plasma lipids in moderate hypercholesterolemic patients. Twenty-two subjects [30-65 years old), 11 males, with total cholesterol (TC) > 240 mg.dL-1, low-density cholesterol (LDL-c) 160-190 mg.dL-1 and plasma triglycerides (TG) < 400 mg.dL-1] were randomized in a double blind clinical trial to receive an amaranth snack (50 g/day) or equivalent corn snack (placebo) for 2 months. There were no differences between amaranth and placebo on TC and LDL-c, and TG respectively: -8.4 and -5.7% (p = 0.17); -12.3 and -9.7% (p = 0.41) and -0.6 and -7.3% (p = 0.47). However, amaranth snacks significantly reduced high-density cholesterol (HDL-c): -15.2 vs. -4% (p = 0.03). In conclusion, the intake of 50 g of extruded amaranth daily during 60 days did not significantly reduce LDL-c in moderate hypercholesterolemic subjects; furthermore there was a significant reduction in HDL-c. Studies with greater number of subjects and greater quantity of this food are necessary to test the effects of amaranth on lipid metabolism in humans.

Cultivar, harvest year, and storage conditions affecting nutritional quality of common beans (Phaseolus vulgaris L.

Sixteen common bean cultivars were compared concerning the physicochemical characteristics of their raw seeds in the course of two consecutive harvests, as well as the effect of storage conditions on starch and dietary fiber content of cooked beans. Using cluster analysis it was possible to identify groups of cultivars with different nutritional features. Bean cultivars were categorized into four different groups according either to their macronutrient content (crude protein-PROT, total dietary fiber-TDF, insoluble dietary fiber-IDF, soluble dietary fiber-SDF, digestible starch-DS, and resistant starch-RS) or to their micronutrient levels (Fe, Zn, Mn, Cu, Ca, Mg, and P). Guateian 6662 and Rio Tibagi appeared to be the most suitable cultivars to prevent nutritional deficiencies, because they had high PROT, DS, Fe, and Zn content. The high total dietary fiber and RS content of Iraí, Minuano, and TPS Bonito cultivars, and specially the high soluble fiber content of Guateian 6662 and Rio Tibagi cultivars suggests that they could have a beneficial role in controlling blood lipid and glucose levels. Cooked beans had a decrease in DS and an increase in RS content after storage (4 °C or -20 °C), but these changes were more prominent in beans that had low RS content before cooking than in those of high RS content. TDF, IDF, and SDF did not change after storage.

Effect of the daily consumption of ostrich and bovine meat on the lipid metabolism in rats

The objective of this study is to evaluate the effect of the daily consumption of ostrich meat (lliofemuralis internus) and bovine meat (Psoas major) on the lipid metabolism in adult mice. The analyses of the centesimal composition of the meats and preparation of the diets were accomplished following the recommendations of the American Institute of Nutrition-AIN-93. Three groups of 150 day-old animals: group I (diet I, with casein), group II (diet II, with ostrich meat), and group III (diet III with bovine meat) were fed for 13 weeks with the respective diets and weight gain, food efficiency coefficient, total cholesterol, lipoprotein fractions, hepatic, transaminases and body fat percentage and hepatic fat content were evaluated. No difference (p < 0.05) it was found for weight gain and coefficients for feed efficiency among the groups. Total cholesterol, HDL-cholesterol, LDL-cholesterol, relationship of total cholesterol/HDL-cholesterol, VLDL, triglycerides and hepatic transaminases were also not different among the groups (p < 0.05). This research suggests that the consumption of ostrich meat or thin bovine meat on a daily basis does not raise concerns about weight gain, and an increase in the plasma concentrations of lipoprotein and levels of hepatic transaminase.

The influence of achyrocline satureioides ("Marcela") extract on the lipid oxidation of salami

The effect of two levels (0.5 and 1%) of hydroalcoholic extract of Achyrocline satureioides on the safety (TBARS values) and quality (pH, water activity, colour, weight loss, and sensorial attributes) of salami was evaluated. The addition of Achyrocline satureioides extract decreased TBARS values significantly during the storage of salami when compared to the control, which was elaborated without Achyrocline satureioides extract. The treatment with 1% of "Marcela" extract showed larger lipid stability than that of the lot with 0.5%, However, it presented a decrease (p < 0.05) in the sensorial acceptance. The two levels of "Marcela" extract did not influence pH, water activity, colour, and weight loss significantly. This study indicates that the hydroalcoholic extract of "Marcela" was effective in decreasing the lipid oxidation and at 0.5% it did not alter the sensorial features; therefore, it may be used in salami to provide safer products for the consumers.

Conjugated linoleic acid supplementation: lipid content and hepatic histology in healthy Wistar rats

This work aimed to evaluate the effects of the consumption of two commercial conjugated linoleic acid (CLA) mixtures on lipid content and liver histology of healthy rats. The investigation was carried out using thirty rats divided into three groups: C (control), AE (AdvantEdge®CLA), and CO (CLA One®). The concentration of CLA was 2% of feed consumption, and the animals were supplemented daily for 42 days. The total lipid content of the liver was determined, and the histology of the organ was examined by Transmission Electronic Microscopy. The results of total liver lipid contents did not exhibit significant differences between the groups. With regard to hepatic histology, it was observed that although fat globules were visibly present in higher numbers and bigger size in the CLA groups, the organ histology was considered normal since both cytoplasm and organelles showed integrity. It was concluded that even though liver microscopic images indicated the presence of fat globules in the liver, from a statistical point of view, the supplementation for 42 days did not bring about lipid accumulation, nor did it alter hepatic histology.

Quinoa (Chenopodium quinoa, Willd.) as a source of dietary fiber and other functional components

Four varieties of an Andean indigenous crop, quinoa (Chenopodium quinoa Willd.), were evaluated as a source of dietary fiber, phenolic compounds and antioxidant activity. The crops were processed by extrusion-cooking and the final products were analyzed to determine the dietary fiber, total polyphenols, radical scavenging activity, and in vitro digestibility of starch and protein. There were no significant differences in the contents of total dietary fiber between varieties of quinoa. In all cases, the contents of total and insoluble dietary fiber decreased during the extrusion process. At the same time, the content of soluble dietary fiber increased. The content of total phenolic compounds and the radical scavenging activity increased during the extrusion process in the case of all 4 varieties. There were significant differences between the varieties and the content of total polyphenols. The in vitro protein digestibility of quinoa varieties was between 76.3 and 80.5% and the in vitro starch digestibility was between 65.1 and 68.7%. Our study demonstrates that quinoa can be considered a good source of dietary fiber, polyphenols and other antioxidant compounds and that extrusion improves the nutritional value.

Lipid and protein oxidation in the internal part of italian type salami containing basil essential oil (Ocimum basilicum L.)

Different concentrations of basil essential oil (Ocimum basilicum L.) (0.19; 0.38; 0.75; 1.87; 3.75 and 6.00 mg.g-1) were evaluated in relation to their antioxidant activity using the DPPH● radical methodology. From the IC50 obtained data, the concentrations of 0.19; 0.38; 0.75; 1.87; 3.75; 6.00 and 12.00 mg.mL-1 were applied directly to the product and these were sensorially evaluated by the test of control difference. The concentrations related to the highest acceptability (0.19; 0.38 and 0.75 mg.g-1) were tested for antioxidant activity in the internal part of Italian type salami - during the processing and after 30 days of storage, in terms of lipid and protein oxidation. The oxidation of lipids was determined using the method of TBARS. The method of carbonyl compounds was employed for proteins oxidation. Five different formulations of salami were elaborated: blank (without the use of antioxidant); control (using sodium eritorbate as antioxidant); and adding 0.19; 0.38 and 0.75 mg.g-1 of basil essential oil. The product was kept between 25 ºC and 18 ºC and UR between 95% and 70%, for 28 days. Analyses were carried out on the processing day and after 2, 7, 14, 21 and 28 days, and also following 30 days of storage. The basil essential oil in vitro presented an antioxidant activity of IC50 12 mg.mL-1. In the internal part of the Italian type salami the commercial antioxidant (control) and the formulation containing 0.75 mg.g-1 of basil essential oil presented antioxidant activity in relation to the lipids, but not to the proteins - during processing and storage.

Serum lipid profile and hepatic evaluation in mice fed diet containing pequi nut or pulp (Caryocar brasiliense Camb.)

Caryocar brasiliense (popular name pequi) is widely consumed by the population of Brazilian Savannah. This fruit has a high concentration of monounsaturated fatty acids that can influence positively the lipid profile. In addition, pequi also has an important concentration of saturated fatty acids which, in turn, is associated with atherosclerosis risk. This study aimed to investigate the effect of a pequi-supplemented diet on blood lipid and glucose levels and hepatic histology. Female Albino swiss mice were divided into three groups and fed a standard chow diet (control group), chow diet supplemented with 33% pequi nut (nut group), and chow diet supplemented with 33% pequi pulp (pulp group). After 6 weeks, following an overnight fast, blood and liver were collected for posterior analyses. Serum total cholesterol and HDL-cholesterol were significantly higher in mice fed pequi-rich diets compared to the control group. Nevertheless, there was no modification in blood triglycerides, atherogenic fraction, and glucose levels. In addition, there was development of liver microvesicular steatosis related to pequi intake. In conclusion, the diets supplemented with pequi nut or pulp reduced the atherogenic risk by increasing the anti-atherogenic lipoproteins without changing the pro-atherogenic fraction in mice.

The use of cashew apple residue as source of fiber in low fat hamburgers

The main purpose of this study was to produce hamburgers with partial substitution of the meat with cashew apple residue powder. The powder residue was obtained after the extraction of the pulp and dehydration in stove with air circulation. Three formulations of hamburgers with increasing concentration of the residue as well as a control sample were prepared. The formulated products with cashew apple residue powder presented lower humidity and proteins and 35% lipid reduction. However, there was an increase in carbohydrates and pH with the addition of the powder from the cashew apple residue. Some formulations showed an improvement of the final product yield. The total dietary fiber value was between 0 and 7.66%, with higher content of insoluble dietary fiber. The addition of up to 10.70% of the residue did not cause significant sensory changes in the flavor of the samples. The production of hamburgers with a partial substitution of cow meat with the cashew apple residue could be a feasible option since it resulted in product with high nutritional quality that is rich or have high dietary fiber content and is low in fat.

Effect of storage and processing of Brazilian flaxseed on lipid and lignan contents

Flaxseed has been widely studied around the world; its incorporation into products habitually consumed by human populations has been stimulated due to its unique nutritional value. The objective of this study was to evaluate the chemical composition of Brazilian flaxseed, to analyze the stability of lipids present in whole flaxseed flour (WFF) or partially defatted flaxseed flour (DFF) stored under several temperatures, and to investigate the effect of bread making on a product containing flaxseed. Whole flaxseed flour presented (g.100 g-1) 25.7 of insoluble fiber, 10.7 of soluble fiber, 38.9 of lipids, and 2.65 of lignan. Defatted flaxseed flour presented 65% less lipids, 36% more fiber and 56% more lignan than whole flaxseed flour. The fatty acid profile was maintained in the defatted flaxseed flour, and it presented a stable composition during storage under ambient temperature, refrigeration, and freezing. The fatty acid profile was similar in the bread containing defatted flaxseed flour after dough development, baking, and storage at room temperature or refrigerated. After baking, 89% of the lignan content was kept in bread. Results show that Brazilian flaxseed has an interesting chemical composition, and that defatted flaxseed, by-product of lipid extraction, presents a good stability to grind and storage under several temperatures. Thus, defatted flaxseed flour can be incorporated in bread, increasing its nutritional and functional value.

Application of roasted rice bran in cereal bars

The objective of this study was to evaluate the viability of using microwave-roasted rice bran as an ingredient in high-fiber cereal bars to obtain a product with good acceptability. The influence of the rice flakes, corn flakes, and roasted rice bran levels on the physical and chemical characteristics of the cereal bars was studied. The overall acceptability of three selected formulations was also evaluated. An increase in the roasted rice bran level in the formulation reduced the force of rupture and water activity, resulted in intermediate density, and caused darkening of the bars. The contents of lipid and total dietary fiber were higher in the formulation with the highest rice bran content, which was therefore classified as functional food. The formulation containing 0.34; 0.32; and 0.34 roasted rice bran, rice flakes, and corn flakes, respectively, seemed to be the best outcome. Cereal bars with roasted rice bran levels between 10 and 20% were accepted by consumers.

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.

Egg quality and yolk lipid composition of laying hens fed diets containing cashew nut meal

The objective of this study was to assess the effect of the addition of cashew nuts meal (0, 5, 10, 15, 20, and 25%) to laying hen diets on egg quality and yolk composition. The variables studied were: egg weight, specific gravity, Haugh Units, percentages of shell, albumen, and yolk, moisture, total solids, total lipids, fatty acids profile, and yolk cholesterol. The addition of up to 25% of cashew nuts meal to hen diets did not affect egg quality and freshness, moisture and total solids content. However, an increase in total lipid content and a decrease in yolk pigmentation was observed. Oleic acid level increased in the yolk, whereas palmitic, stearic, and linoleic acid levels decreased. The addition of cashew nuts meal increased the monounsaturated/saturated fatty acid ratio in the yolk and reduced the cholesterol content. Therefore, the use of cashew nuts meal in laying hen diets favorably modifies the fatty acid composition of egg yolk and contributes to a better acceptance of this food by consumers since it also reduces yolk cholesterol levels.