SO32– effects the 5‐hydroxymethyl‐2‐furaldehyde content in ammonium sulphite–glucose solutions

Effects of sulphite concentration on ammonium sulphite–glucose solution’s pH value and browning intensity were studied. Results showed both the solution’s pH value and browning intensity changed significantly in relation to the increases in SO₃^2– concentration. 5‐hydroxymethyl‐2‐furaldehyde was measured by nuclear magnetic resonance and HPLC. This study indicates that the changes of 5‐hydroxymethyl‐2‐furaldehyde content accompanied changes in browning intensity. Moreover, adding ammonium sulphite significantly reduced the 5‐hydroxymethyl‐2‐furaldehyde content. The mechanism may be that SO₃^2– limits the formation of N‐glucosamine, an important precursor for forming 5‐hydroxymethyl‐2‐furaldehyde, by reacting with glucose, which could not form an imine in further reaction.     

Flavan‐3‐ol C‐glycosides – Preparation and model experiments mimicking their human intestinal transit

In order to study the human intestinal transit of flavan‐3‐ol C‐glycosides, several C‐glycosyl derivatives were prepared by non‐enzymatic reaction of (+)‐catechin with α‐D ‐glucose, α‐D ‐galactose and α‐D ‐rhamnose, respectively. In contrast to literature data, we propose that the reaction mechanism proceeds in analogy to the rearrangement of flavan‐3‐ols during epimerization under alkaline conditions. Four of the 12 synthesized flavan‐3‐ol C‐glycosides were incubated under aerobic conditions at 37°C using saliva (2 min) and simulated gastric juice (3 h). To simulate human intestine, the C‐glycosides were also incubated under anaerobic conditions at 37°C both in human ileostomy fluid (10 h) and colostomy fluid (24 h), respectively. The flavan‐3‐ol C‐glycosides under study, i.e. (+)‐epicatechin 8‐C‐β‐D ‐glucopyranoside (1a), (+)‐epicatechin 6‐C‐β‐D ‐glucopyranoside (1d), (+)‐catechin 6‐C‐β‐D ‐galactopyranoside (2b), (+)‐catechin 6‐C‐β‐D ‐rhamnopyranoside (3b) were analyzed in the incubation samples by HPLC‐DAD and HPLC‐DAD‐MS/MS. They were found to be stable in the course of incubation in saliva, simulated gastric juice and ileostomy fluid and underwent degradation in colostomy fluid. While the 6‐C‐β‐D ‐glucopyranoside 1d was completely metabolized between 2 and 4 h, decomposition of the 6‐C‐β‐D ‐galactopyranoside 2b reached only 16±2% within 4 h of incubation. Linear degradation rates of 1d and 2b in colostomy fluid differed significantly. As microbial metabolism of flavan‐3‐ols is known not to be influenced by the stereochemistry of the aglycon, varying degradation rates are ascribed to the effect of the sugar moiety. Based on these results we assume that flavan‐3‐ol C‐glycosides pass through the upper gastrointestinal tract (oral cavity, stomach and small intestine) unmodified and are then metabolized by the colonic microflora.     

Diet‐induced obesity regulates the galanin‐mediated signaling cascade in the adipose tissue of mice

Galanin is a neuropeptide that regulates the food intake, neurogenesis, memory, and gut secretion. This study was conducted to evaluate the high‐fat diet (HFD)‐induced regulation of the galanin receptors (GalRs) and the associated signaling molecules in the adipose tissues of mice. Twenty C57BL/6J mice were given either an HFD or a normal diet for 12 wk. The results of the semiquantitative RT‐PCR analyses indicated that the HFD upregulated the expression of GalR1, GalR2, GalR3, resistance to audiogenic seizures, peroxisome proliferator‐activated receptorγ2, adipocyte protein 2, and protein kinase Cδ and downregulated the expression of peroxisome proliferative activated receptor γ coactivator 1α and uncoupling protein 1 in the adipose tissues. The immunoblot results showed that the protein levels of peroxisome proliferator‐activated receptorγ2 and adipocyte protein 2, and the phosphorylation of c‐Raf and extracellular signal‐regulated kinase 1/2 were increased, while the phosphorylation of cyclic adenosine monophosphate‐responsive element‐binding protein, which regulates peroxisome proliferative activated receptor γ coactivator 1α and uncoupling protein 1, was decreased in the epididymal adipose tissues of the HFD‐fed mice. These results suggest the possible association of the galanin‐mediated signaling pathways in the manifestation of the HFD‐induced activation of adipogenesis along with the suppression of thermogenesis in the adipose tissues of mice.     

Protein quality of drum‐processed cereal–bean–sardine composite supplementary foods for preschool‐age children

Acute, severe undernutrition during childhood remains a common health problem in many parts of the world and makes a significant contribution to childhood mortality. This study was conducted to evaluate the protein quality and growth/rehabilitation potential of supplementary foods developed from locally produced materials in Tanzania. Six diets, namely rice meal (RM), bean meal (BM), rice–bean meal (RBM), rice–bean–sardines meal (RBSM), corn–bean–sardines meal (CBSM) and corn–bean meal (CBM), were formulated to maximise the amino acid score as recommended by FAO/WHO/UNU for preschool children. Biological qualities of the diets, including apparent and true protein digestibility, net protein retention ratio, food efficiency ratio, protein digestibility‐corrected amino acid score and rehabilitation potential, were evaluated using Sprague Dawley weanling rats. Net protein retention ratio varied significantly (p < 0.05) among control diet (0.93), RBSM (0.92), CBSM (0.86), RM (0.66), RBM (0.44), CBM (0.28), BM (0.12) and corn meal (CM) diet (?0.40). True protein digestibility ranged between 82 and 99%, with BM showing the lowest digestibility. The protein digestibility‐corrected amino acid scores were 100% (control diet), 77% (CBSM), 89% (RBSM), 58% (RM), 90% (RBM), 47% (CBM), 85% (BM) and 48% (CM). Two test diets, CBSM and RBSM, showed the greatest potential to support growth and rehabilitation of undernourished rats, while CBM, RBM, BM and CM did not display acceptable growth. These results suggest that cereal–bean–sardine composites are of high quality and have potential for use as supplementary/rehabilitation foods for preschool‐ and school‐age children as well as adults. Copyright © 2004 Society of Chemical Industry     

Acceptability,storage stability and costing of α‐amylase‐treated maize–beans–groundnuts–bambaranuts complementary blend

The effects of α‐amylase treatment on physical properties, acceptability to mothers, and cost of roasted and extruded maize–beans–groundnuts–bambaranuts complementary porridge recipes were assessed prior to their industrial production. Storage stability of the extruded α‐amylase‐treated fortified blend was assessed at 2 weeks and 6 months by sensory evaluation, peroxide value, water activity and microbiological load. The use of α‐amylase at 0.04% w/w enhanced porridge acceptability and resulted in 88% and 122% increase in flour concentration for roasted and extrusion‐cooked porridge flour, respectively, while maintaining porridge viscosity at 1000‐fold lower than that of traditionally used porridges. The extrusion cooked blend was stable for 6 months. α‐Amylase application increased the unit cost of the developed blend by only 1.4%. The total cost was less than US $ 2 kg^?1, half the minimum price of commercially available complementary foods. Further work on marketing and the efficacy of this inexpensive food on growth of infants is warranted. Copyright © 2007 Society of Chemical Industry     

Degradation of N‐(1‐Deoxy‐d‐xylulos‐1‐yl)glycine and N‐(1‐Deoxy‐d‐xylulos‐1‐yl)proline using thermal treatment

The formation and degradation of N‐(1‐Deoxy‐d ‐xylulos‐1‐yl)glycine and N‐(1‐Deoxy‐d ‐xylulos‐1‐yl)proline, derived from the secondary amine Maillard reaction in xylose‐amino acid model solutions, were detailed in this study. The identification and quantitative analysis of N‐(1‐Deoxy‐d‐ xylulos‐1‐yl)glycine and N‐(1‐Deoxy‐d‐ xylulos‐1‐yl)proline were carried out using high‐performance anion‐exchange chromatography and high‐performance liquid chromatography. The formation of intermediate and advanced products derived from N‐(1‐Deoxy‐d‐ xylulos‐1‐yl)glycine and N‐(1‐Deoxy‐d‐ xylulos‐1‐yl)proline was also tested using an UV‐Vis spectrophotometer to gain a better comparing of the degradation process of the two important Maillard reaction products using thermal treatment. Results showed that the degradation of N‐(1‐Deoxy‐d‐ xylulos‐1‐yl)glycine was more significant than N‐(1‐Deoxy‐d‐ xylulos‐1‐yl)proline. Moreover, xylose was tested in the degradation products of both N‐(1‐Deoxy‐d‐ xylulos‐1‐yl)glycine and N‐(1‐Deoxy‐d‐ xylulos‐1‐yl)proline, which indicated that the degradation of N‐substituted 1‐amino‐1‐deoxyketoses was a reversible reaction to form reducing sugar.     

Physicochemical and sensory characteristics of no‐bake wheat–soy snack bars

BACKGROUND: Health and wellness is a trend observed throughout ready‐to‐eat cereals, cereal health bars. Therefore, the main objectives of this research were to produce a low cost, acceptable, nutritious and healthy wheat‐ and soy‐based bar under no‐bake conditions. Also, the physical, chemical, microbial, acceptability and the nutritional value of this product were studied. Six different bars were produced: a wheat bar (WB), a wheat bar with coating (WBC), a wheat and soy bar with coating (WSBC), a soy bar with coating (SBC), a wheat bar with 3% glycerin (WB3%), and a wheat bar with 6% glycerine (WB6%). RESULTS: WB and WBC had the highest water activities while WSBC had the lowest. The three bars with coating had higher L and lower b values, which indicates that they were lighter and not as highly yellow coloured as the wheat samples. WSBC had the lowest value for hardness while the SBC and WBC had the highest. SBC received the highest scores for overall acceptability, appearance, sweetness, flavour and texture while WSBC received the second highest score in all categories. CONCLUSION: It appears that consumers prefer the soy varieties to the wheat bars. These types of bars can aid in feeding the general population, which is becoming increasingly concerned with nutrition and convenience. Copyright © 2010 Society of Chemical Industry