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We investigated whether dietary supplementation with Aurantiochytrium sp. meal, a DHA-rich source (docosahexaenoic acid, 22: 6 n-3), fed during long-term exposure to cold-suboptimal temperature (22 °C, P1), followed by short-term exposure to higher temperatures (28 °C, P2, and 33 °C, P3), would promote oxidative damage in Nile tilapia (Oreochromis niloticus). Two supplementation levels were tested: 1.0 g 100 g

Nile tilapia farming occurs in tropical and subtropical climate areas worldwide but information about dietary fatty acid requirements of Nile tilapia, particularly when raised at suboptimal temperature, are scarce. Previous studies with Nile tilapia failed to detect growth differences at suboptimal growth temperatures. Therefore, the objective of this study was to estimate the dietary requirement of α-linolenic acid (α-LNA, 18:3n − 3) of juvenile Nile tilapia, when raised at 22 °C. Increasing levels of linseed oil were added to a mixture of vegetable oils, yielding the following concentrations of α-LNA: 0.03, 0.21, 0.37, 0.67 and 0.99% of diet dry weight. The basal diet was formulated with semipurified ingredients and contained 5% lipid. Juvenile tilapia (10.6 ± 0.09 g) were fed the experimental diets twice daily until satiation for 14 weeks. The average water temperature throughout the experimental period was 22.12 ± 0.17 °C. The increase in dietary α-LNA significantly affected daily weight gain, specific growth rate, feed efficiency and daily feed intake. Total n − 3 fatty acid content in muscle showed a significant linear response to dietary α-LNA. Likewise, an accumulation of muscle linoleic acid (18:2n − 6) was directly related to the increase in dietary α-LNA, while n − 6 long-chain polyunsaturated fatty acids (LC-PUFA) decreased. The dietary requirement of α-LNA estimated for juvenile Nile tilapia reared at 22 °C was 0.70% diet for maximum weight gain and 0.68% for maximum feed efficiency. Statement relevance Nile tilapia, a tropical species, has been considered for aquaculture in subtropical regions, but its nutritional requirements under suboptimal temperatures are unknown. The present study shows that the α-linolenic requirement for this species under 22 °C is slightly higher than in 28 °C. Therefore, we suggest the increase in the α-linolenic levels in the diet for Nile tilapia during the cold seasons.

Five sources of dietary fatty acids (fish, linseed, sunflower, olive and coconut oils) were evaluated in juvenile Nile tilapia in two trials: at optimal (28°C) and suboptimal (22°C) temperatures lasting 9 and 12 weeks, respectively. At 28°C, there was no clear effect of dietary source on fish growth, but at 22°C, the highest daily weight gain occurred in fish fed sunflower, linseed and fish oil. Feed efficiency and apparent net protein utilization increased as the amount of unsaturated fatty acids, especially n-3 polyunsaturated fatty acids (PUFA), in the diet increased. Coconut oil, which is rich in saturated fatty acids (SFA), led to the worst growth results, especially at 22°C, with the lowest weight gain, feed intake and feed utilization by tilapia. The body fatty acid profile, in % of total fatty acids, was dependent on diet composition. However, for all treatments, PUFA body content increased with the decrease in temperature, but SFA and monounsaturated fatty acids remained the primary contributors to the body profile. Either fish oil or vegetable oil may be used as sources of dietary fatty acids for Nile tilapia, but at suboptimal temperatures, a dietary source containing more PUFA and less SFA improves performance.

Young wheat (Triticum aestivum) leaves contain concentrated nutrients that may be beneficial as a nutritional supplement to those with malabsorption disorders such as celiac disease (CD) if both gluten-free, and free of gluten contamination. The tender 8-10 day leaves are juiced and the juice is consumed, added to smoothies, or consumed as a purchased wheatgrass dietary supplement in tablet, capsule and liquid forms. CD and other gluten related disorders cause both malabsorption of nutrients and an abnormal immune reaction to gluten. The only effective therapy is a lifelong gluten-free diet. Codex Alimentarius sets the gluten threshold level at 20 mg/kg for gluten-free foods. This threshold has been adopted by many regulatory agencies such as European Commission and the US Food and Drug Administration. Consumption of wheatgrass extract has been reported to alleviate symptoms of ulcerative colitis and anaemia which are often symptoms of CD. This investigation utilised the R5 and G12 sandwich enzyme-linked ...

Gluten is an important protein complex for baking products found in wheat, rye, barley, and some oat varieties. However, some people need to avoid these grains and their products because they result in gluten-related disorders. The only treatment for these individuals is to engage in a gluten-free diet. The objective of this work was to verify if the gluten content of several commercial food products sold in Brazil complied with their labeling. The Mendez ELISA R5 sandwich method was used to analyze 437 samples, and of these, 70% were labeled as gluten-free, 26% as containing gluten, and 4% not labeled in relation to gluten. The results indicated that 89% of the products labeled as gluten-free were correctly labeled and 11% were not, which represented a risk for celiac people.

Background: β-glucans (1-3: 1-4) are soluble fibers applied to foods due to their technological properties (water binding capacity, viscosity, emulsification and stabilization) and their beneficial effects on health. The functional properties of β-glucans can be lost during the extraction and purification processes. The high viscosity of β-glucans is related to a high molecular weight and its physiological properties in the intestine. Therefore, to characterize the fiber after its extraction and purification is fundamental to understand its possible applications in foods. Objectives: characterize β-glucans extracted (EβG) and compare them with three commercial β-glucans (CβG-A, CβG-B and CβG-C) to identify its possible applications in foods and to evaluate if enzymatic purification affects molecular and structurally the β-glucans. Methods: barley β-glucans were extracted (EβG), characterized by chemical analyzes, rheological behavior, and color, and compared to three commercial β-glucans samples. Then, the extract was purified and its structural and molecular characteristics were calculated. Results: EβG contained 64.38 ± 3.54% of β-glucans, high starch contamination (12.70 ± 1.73%), high content of calcium (8894 mg/kg), pseudoplastic behavior, and dark color (L* = 52.77 ± 0.7). All commercial samples showed low starch contamination, lighter color, and Newtonian behavior. After purification starch and protein contamination decreased (0.85 ± 0.46% and 5.50 ± 0.12% respectively), increased the content of βG (69.45 ± 0.81%) and increased brightness (L* = 92.60 ± 1.70). Purified β-glucans (PβG) showed a molar weight of 690 ± 1.6 kDa and species with degree polymerization 3 (DP3) to 11 (DP11) were identified on the structure. Conclusions: EβG extracts before the purification presented a high viscosity and contamination. The enzymatic purification process was effective and allowed to maintain a high molar mass of PβG and its distinctive molecular structures (species with DP3 and DP4). The commercial samples CβG-A and CβG-B showed a low content of β-glucans. Finally, CβG-C presented the best physicochemical and rheological properties for its subsequent application in food.

article i nfo Omnivorous fish utilize dietary carbohydrates better than carnivorous ones due to striking morphological and physiologicaldifferencesintheirdigestivetracts.However,digestivetractmorphologyandphysiologyalsovaries among omnivorous fishes, which can lead to different dietary utilization of plant sources as well. Starch, energy, and dry matter apparent digestibility coefficient (ADC) of wheat bran, cassava residue, ground corn, and broken rice were compared between the omnivorous freshwater jundia catfish (93.9 ± 34.0 g; mean ± standard deviation) and Nile tilapia (93.7 ± 51.6 g) by using 5 g kg �1 chromic oxide as a diet marker. Starch ADCs were significantly higher in tilapia for all plant sources (92.02% to 99.74% versus 55.87% to 90.61%), except for wheat bran, which was similar to that found in jundia. Starch-richer plant sources (ground corn and broken rice) showed the lowest starch digestibility for jundia. However, ground corn provided significantly higher energy digestibility in jundia (55.35%), as opposed to broken rice (86.59%) and ground corn (71.68%), in tilapia. Dry matter ADCs ranged from 22.89% for cassava residue in jundia to 89.17% for broken rice in tilapia. Higher dry matter ADCs were registered in tilapia for all plant sources, except for wheat bran. Despite presenting lower starch and energy digestibilities, jundia catfish showed an adaptive capacity to utilize starch sources by present- ing significantly higher specific activity of amylase (58 U mg protein �1

The cellular structure of healthy food products, with added dietary fiber and low in calories, is an important factor that contributes to the assessment of quality, which can be quantified by image analysis of visual texture. This study seeks to compare image analysis techniques (binarization using Dtsu’s method and the default ImageJ algorithm, a variation of the iterative intermeans method) for quantification of differences in the crumb structure of breads made with different percentages of whole-wheat flour and fat replacer, and discuss the behavior of the parameters number of cells, mean cell area, cell density, and circularity using response surface methodology. Comparative analysis of the results achieved with the Dtsu and default ImageJ algorithms showed a significant difference between the studied parameters. The D tsu method demonstrated the crumb structure of the analyzed breads more reliably than the default ImageJ algorithm, and is thus the most suitable in terms of structural representation of the crumb texture.

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