The muscles of freshwater clam and whole
Gracilaria powder (WG) were separately extracted using hot water. The residual meat was first freeze-dried, then hydrolysed at 50
°C by Protamex to obtain ...freshwater clam hydrolysate (PX5). The WG was separated into two fractions, designated as soluble (SDF) and insoluble dietary fibre (IDF). The
in vitro bile acid-binding capacities and inhibition of micellar solubility of cholesterol were then investigated using the compounded PX5 and dietary fibre of WG or IDF. Assuming that bile acid binds to cholestyramine at 100%, the relative bile acid-bindings of PX5 and WG were 35.9% and 41.1%, respectively. Bile acid-binding of compounded PX5 and WG showed the best synergistic effect at a ratio of 1:3 (w/w) and relative bile acid-binding of 45.7%, significantly higher than PX5 and WG alone. After peptic digestion, the resulting inhibitions against cholesterol micelle formation in cholestyramine, PX5, WG and IDF were 97.6%, 18.5%, 30.8% and 49.3%, respectively.
► Common bean is vital for the Nicaraguan population. ► Crop storage conditions are hot and humid. ► Bioavailability of iron and zinc is low. ► Hot moist storage decreased quality but marginally ...increased bioavailability. ► Small changes in dietary fibre composition occurred in storage.
Common bean (Phaseolus vulgaris L.), the staple crop of Nicaragua, provides protein and nonhaem iron, but inhibitors such as phytate may prevent absorption of iron and zinc by the consumer. Warehouses in Nicaragua do not have controlled atmospheres, so beans are exposed to high temperatures and humidities that may accelerate quality loss. To evaluate the impact of 6months of storage on quality, four national accessions of common bean were submitted to two treatments, a conventional warehouse with uncontrolled temperature and humidity, and accelerated ageing at 40°C and 75% RH. Iron content was 61–81mg/kg of which 3–4% was bioavailable, and zinc content was 21–25mg/kg, of which 10–12% was bioavailable. Bioavailability generally increased in storage, significantly so in year-old INTA Linea 628 in accelerated ageing. The concentration of phytate was 8.6–9.6mg/g and it contained 54–63% of the total phosphorus. Improvement in bioavailability of divalent cations is needed.
The fibre composition of four spelt genotypes and of three wheat genotypes was studied on three grindings: bran, whole bare grains flour for all genotypes, and whole hulled grains flour for spelt ...only. Insoluble fibre and soluble fibre contents were measured after removal of proteins, starch and ashes from the sample (
Lee, Prosky, & De Vries, 1992). Cellulose, hemicellulose and lignin contents were measured according to the same principles with different chemical degradations of the sample (
Van Soest & Wine, 1967). Spelt and wheat bran and whole grain flour displayed significant statistical differences for hemicellulose and cellulose contents. Variability amongst the spelt genotypes was much higher than amongst the wheat genotypes. The study also highlighted the special profile of the true baking variety Ressac and the richness in fibres of the landrace 140. Finally, various methods of measurement were compared and a combination of these methods was proposed for cereal grains dietary fibre analysis.
Wheat bran is rich in dietary fibre and its annual output is abundant, but underutilized. Insoluble dietary fibre often influences food quality negatively; therefore, how to improve the physical and ...chemical properties of insoluble dietary fibre of wheat bran for post processing is a challenge. Insoluble dietary fibre was obtained from wheat bran and micronized using high-pressure homogenization, high-intensity sonication, and a combination of these two methods. The high-pressure homogenization and high-pressure homogenization+high-intensity sonication treatments significantly (p<0.05) improved the solubility, swelling, water-holding, oil-holding, and cation exchange capacities. The improvement of the above properties by high-intensity sonication alone was marginal. In most cases, the high-pressure homogenization process was as good as the high-pressure homogenization+high-intensity sonication process in improving the above-mentioned properties; hence, the contribution of high-`intensity sonication in the high-pressure homogenization+high-intensity sonication process was minimal. The best results show that the minimum particle size of wheat bran can reach 9 μm, and the solubility, swelling, water-holding, oil-holding, cation exchange capacities change significantly.
Oats are rich in dietary fibre (DF) especially in β-glucan which has several health-promoting effects. Oats are not commonly used in extruded snacks because they often result in a poor expansion and ...hard structure. In the present study, defatted wholegrain oat flour (WF) and defatted endosperm oat flour (EF) were used as starch sources for extrudates. Five differently treated oat bran fractions (untreated, ultra-fine ground, enzymatically hydrolysed and hot water-extracted solubles and residue) were added to EF (10 or 20 %), and their influence on the chemical, textural and structural properties of extrudates was investigated. Extrudates made of WF had a poor expansion (151 %) and hard texture (399 N), whereas EF formed a better expanded (199 %) and less hard product (149 N). Addition of oat bran concentrate (OBC) decreased the expansion (171–176 %) and resulted in a harder texture (200–265 N) compared to that of EF 100 % extrudates. The lower expansion of WF and OBC-enriched extrudates was due to the higher content of insoluble fibre. However, no statistical differences were detected between the untreated, ultra-fine ground and enzyme-hydrolysed OBC. The water-insoluble (WIS-OBC) and water-soluble (WS-OBC) fractions had opposite effects on the EF-based extrudates: 10 % addition of WIS-OBC fraction significantly decreased the expansion (163 %) and increased the hardness (313 N), whereas the addition of WS-OBC (10 or 20 %) enhanced the expansion (218–226 %) and resulted in less hard textures (131–146 N). The soluble fibres and low protein content in WS-OBC fraction were hypothesised to cause the improved expansion and decreased hardness. The results demonstrated that extrudates with acceptable expansion and hardness can be produced with defatted oat endosperm flour and oat bran fractions. However, the water-insoluble bran components had a negative effect on the textural properties of extrudates.
This work compared the quantification of soluble fibre in feeds using different chemical and in vitro approaches, and studied the potential interference between soluble fibre and mucin ...determinations. Six ingredients: sugar beet pulp (SBP), SBP pectins, insoluble SBP, wheat straw, sunflower hulls and lignocellulose, and seven rabbit diets, differing in soluble fibre content, were evaluated. In experiment 1, ingredients and diets were analyzed for total dietary fibre (TDF), insoluble dietary fibre (IDF), soluble dietary fibre (SDF), aNDFom (corrected for protein, aNDFom-cp) and 2-step pepsin/pancreatin in vitro DM indigestibility (corrected for ash and protein, ivDMi2). Soluble fibre was estimated by difference using three procedures: TDF–IDF (SDFIDF), TDF–ivDMi2 (SDFᵢᵥDMᵢ₂), and TDF–aNDFom-cp (SDFₐNDFₒₘ₋cₚ). Soluble fibre determined directly (SDF) or by difference as SDFᵢᵥDMᵢ₂ were not different (109g/kg DM, on average). However, when it was calculated as SDFₐNDFₒₘ₋cₚ the value was 40% higher (153g/kg DM, P<0.05), whereas SDFIDF (124g/kg DM) did not differ from any of the other methods. The correlation between the four methods was high (r≥0.96; P≤0.001; n=13), but it decreased or even disappeared when SBP pectins and SBP were excluded and a lower and more narrow range of variation of soluble fibre was used. In experiment 2, the ivDMi2 using crucibles (reference method) were compared to those made using individual or collective ankom bags in order to simplify the determination of SDFᵢᵥDMᵢ₂. The ivDMi2 was not different when using crucibles or individual or collective ankom bags. In experiment 3, the potential interference between soluble fibre and intestinal mucin determinations was studied using rabbit intestinal raw mucus, digesta and SBP pectins, lignocelluloses and a rabbit diet. An interference was observed between the determinations of soluble fibre and crude mucin, as contents of TDF and apparent crude mucin were high in SBP pectins (994 and 709g/kg DM) and rabbit intestinal raw mucus (571 and 739g/kg DM). After a pectinase treatment, the coefficient of apparent mucin recovery of SBP pectins was close to zero, whereas that of rabbit mucus was not modified. An estimation of the crude mucin carbohydrates retained in digesta TDF is proposed to correct TDF and soluble fibre digestibility. In conclusion, the values of soluble fibre depend on the methodology used. The contamination of crude mucin with soluble fibre is avoided using pectinase.
Dietary fibre intake has been suggested to reduce blood glucose levels in diabetic patients, particularly when glycosylated Hb (HbA1c) levels are high. In the present study, we used a quantile ...regression (QR) approach to characterise the possible heterogeneous associations of dietary fibre intake with HbA1c levels in Chinese diabetic patients. A total of 497 diabetic patients participated in the baseline survey in 2006 and in the follow-up survey in 2011, both of which were conducted in Pudong New Area of Shanghai, China. Structured in-person interviews were conducted to collect information on demographic characteristics and lifestyle factors. Dietary intake was assessed using a validated FFQ. Blood samples were collected during the interviews for biochemical assays. QR models were used to examine the heterogeneous associations of dietary factors with HbA1c levels. A significant marginal association of insoluble dietary fibre intake with subsequent HbA1c levels was observed only when the HbA1c level was over 6·8%. The associations appeared to be greater when the quantile levels of HbA1c were higher. The coefficient estimates were -0·174 (95% CI -0·433, -0·025) at the quantile of 0·60, -0·200 (95% CI -0·306, -0·008) at 0·70, -0·221 (95% CI -0·426, -0·117) at 0·80, and -0·389 (95% CI -0·516, -0·018) at 0·90. A similar pattern was observed for the associations of dietary glycaemic index (GI) value with HbA1c levels. In conclusion, the present results indicate that the associations of insoluble dietary fibre intake and GI value with subsequent HbA1c levels depend on glycaemic control status in Chinese diabetic patients. More studies are required to confirm our findings.
This study investigates the hypocholesterolemic effects of a diet containing freshwater clam hydrolysate (PX) and insoluble dietary fibre from whole
Gracilaria (IDF). Freshwater clam meat and whole ...dried
Gracilaria were separately extracted using hot water. The residual meat was hydrolysed at 50
°C by Protamex to obtain freshwater clam hydrolysate (PX). Levels of triacylglycerol and cholesterol in Sprague–Dawley (SD) rats were compared with those of rats fed diets containing casein and cellulose as a control. Plasma triacylglycerol levels decreased by 65.8%, 27.9%, and 44.3%, respectively, in PX10 (16.6% hydrolysate), IDF10 (13.0% IDF) and compounded PX10/IDF10 groups, while plasma total cholesterol levels decreased by 26.1%, 24.2%, and 17.1%, respectively. In the liver, triacylglycerol levels decreased by 27.6%, 21.0%, and 28.0%, respectively, while total cholesterol levels decreased by 50.0%, 38.5%, and 48.6%, respectively. The compound PX10/IDF10 diet group showed a higher excretion of faecal total cholesterol and bile acids levels than did the other groups.
Resistant starch (RS) is that fraction of starch, which escapes enzymic hydrolysis in the small intestine and passes in the colon. Effect of storage time (12 and 24 h) and temperature (4 °C and 25 ...°C) was studied on RS content of the pressure‐cooked cereal and legume grains/seeds and their flours. RS content was observed to increase in the stored cereals and legumes, with more enhanced increase in the flour samples stored at refrigeration temperature for longer duration (41.4% in wheat flour and 85.4% in pea flour). Significant positive correlations were observed between RS content (4 °C, 24 h) and amylose (y = 0.388 × -5.948, r = 0.840, P ≤ 0.05, n = 7) as well as between % increase in insoluble dietary fibre content (4 °⁰C, 24 h) and amylose (y = 2.257 × -27.724, r = 0.971, P ≤ 0.05, n = 7). Reduced in vitro starch digestibility of the cooked/stored samples (4 °C, 24 h) was observed when compared to freshly cooked samples.
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