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Consumption of certain berries appears to slow postprandial glucose absorption, attributable to polyphenols, which may benefit exercise and cognition, reduce appetite and/or oxidative stress. This randomised, crossover, placebo-controlled study determined whether polyphenol-rich fruits added to carbohydrate-based foods produce a dose-dependent moderation of postprandial glycaemic, glucoregulatory hormone, appetite andex vivooxidative stress responses. Twenty participants (eighteen males/two females; 24 (sd5) years; BMI: 27 (sd3) kg/m2) consumed one of five cereal bars (approximately 88 % carbohydrate) containing no fruit ingredients (reference), freeze-dried black raspberries (10 or 20 % total weight; LOW-Rasp and HIGH-Rasp, respectively) and cranberry extract (0·5 or 1 % total weight; LOW-Cran and HIGH-Cran), on trials separated by ≥5 d. Postprandial peak/nadir from baseline (Δmax) and incremental postprandial AUC over 60 and 180 min for glucose and other biochemistries were measured to examine the dose-dependent effects. Glucose AUC0–180 mintrended towards being higher (43 %) after HIGH-Raspv.LOW-Rasp (P=0·06), with no glucose differences between the raspberry and reference bars. Relative to reference, HIGH-Rasp resulted in a 17 % lower Δmaxinsulin, 3 % lower C-peptide (AUC0–60 minand 3 % lower glucose-dependent insulinotropic polypeptide (AUC0–180 min)Pex vivooxidation, appetite-mediating hormones or appetite. Fortification with freeze-dried black raspberries (approximately 25 g, containing 1·2 g of polyphenols) seems to slightly improve the glucoregulatory hormone and glycaemic responses to a high-carbohydrate food item in young adults but did not affect appetite or oxidative stress responses at doses or with methods studied herein.

An efficient enzymatic route for the synthesis of conducting oligomer of substituted aniline complexed with poly(sodium 4-styrenesulfonate) is presented. This polyelectrolyte assisted horseradish peroxidase catalyzed oligomerization of ortho-toluidine provides a route to synthesize water-soluble, highly conductive oligomers under acidic conditions. The UV-Vis, FTIR, thin film conductivity, molecular weight assessment and modeling studies of the oligomer/polymer complex indicate the presence of a thermally stable and electroactive oligomer with extended conjugation that was not present in similar conductive polymers (e.g. PANI). Moreover, the use of water-soluble templates provide a unique combination of properties such as high conductivity and processability. The same procedure was also implemented for the polymerization of 2,6-xylidine: however, the reaction did not occur suggesting a much more complex stereo-specificity of the enzymatic polymerization. Modeling studies were used to explain this behavior. The conductive poly(ortho-toluidine) can be used in chemiresistive sensors for the detection of humidity.

Polyphenols are a heterogeneous group of phytochemicals that are found in plant-based foods, which have antioxidant and anti-inflammatory properties that may ultimately help protect against chronic diseases, such as cancer and cardiometabolic disease. Flavanols (i.e., a subclass of polyphenols), in particular, have been shown to promote glycemic control when consumed with a high-carbohydrate containing food item. Flavanol structures include complex, hydroxylated arrangements, also known as “tannins”, which associate strongly with proteins and thus are notable for their effect on dietary enzymes. Tannins are furthermore divided into non-hydrolysable proanthocyanidin (PAC) and hydrolysable fractions. This review includes recent findings of in vivo and in vitro effects of flavanols/tannins on blood glucose management and inhibition of the digestive enzymes α-amylase and α-glucosidase. Mechanisms underlying the interaction between flavanol structure and glycemic response (e.g., inhibition of starch digestion, altered transport and absorption of glucose, and the altered secretion of gastrointestinal hormones) are discussed, with an emphasis on the molecular basis for flavanol-enzyme interactions that lead to inhibition of enzyme activity.

UNLABELLED Rosmarinic acid and Epigallocatechin gallate concentrations were studied as natural inhibitors of Maillard browning in glucose/glycine model systems, and in bakery rolls and applesauce. The concentrations of the inhibitors were varied to determine the highest level of inhibition without a pro-oxidant/browning effect. UV absorbance and gas chromatography/mass spec (GC/MS) with solid phase microextraction (SPME) sampling was used to study browning in the model systems. Hunter L*, a*, b* was used to analyze the color change results of the inhibitors on applesauce and bakery rolls. It was determined that a 1.0% solution of either antioxidant in the glucose/glycine system produced the greatest inhibition and a synergistic effect was not apparent when the two were combined. Inhibition of browning and a lack of synergy between the antioxidants were also determined in food systems consisting of applesauce and bakery rolls. GC/MS analysis of the model system revealed a high level of pyrazine formation in no-inhibitor control samples and the absence of pyrazines in inhibitor-containing samples. PRACTICAL APPLICATION Natural browning inhibitors, that is Rosmarinic acid and Epigallocatechin gallate, can be added to food items to inhibit browning over a prolonged period of storage in order to increase product shelf stability. The concentrations of the inhibitors require optimization since a pro-oxidant effect and increased browning will occur at high levels.

This report documents a storage study of a novel technology to inhibit moisture migration in multi-component foods, specifically shelf-stable military rations, conducted in FY 2013 and 2014 by the Natick Soldier Research, Development and Engineering Center (NSRDEC). Edible laminated layers (LL) were inserted as barriers in a model food system and later in a shelf-stable pizza to evaluate their ability to inhibit moisture migration and improve sensory quality. Moisture migration can produce unpleasing physical and chemical changes in multi-component foods, affecting safety, shelf life, and sensory quality. These phenomena occur over time due to differences in the water activity of individual components in the product. Five of the seven LL barriers evaluated inhibited moisture migration between sandwich layers that had differences in water activity. The effectiveness of the various LLs seemed to be largely dependent on film thickness and material. Two of the three films evaluated in the pizza proved effective in slowing moisture migration to the crust during 2 weeks of storage at 120 deg F, but were inconsistent after 4 weeks at that temperature and 3 and 6 of storage at 100 deg F. None of the three LLs significantly increased sensory quality characteristics in the pizza prototypes. This research will be useful in future product development for ration and commercial items that are prone to moisture migration.

Rosmarinic acid and Epigallocatechin gallate concentrations were studied as natural inhibitors of Maillard browning in glucose/glycine model systems, and in bakery rolls and applesauce. The concentrations of the inhibitors were varied to determine the highest level of inhibition without a pro-oxidant/browning effect. UV absorbance and gas chromatography/mass spec (GC/MS) with solid phase microextraction (SPME) sampling was used to study browning in the model systems. Hunter L*, a*, b* was used to analyze the color change results of the inhibitors on applesauce and bakery rolls. It was determined that a 1.0% solution of either antioxidant in the glucose/glycine system produced the greatest inhibition and a synergistic effect was not apparent when the two were combined. Inhibition of browning and a lack of synergy between the antioxidants were also determined in food systems consisting of applesauce and bakery rolls. GC/MS analysis of the model system revealed a high level of pyrazine formation in no-inhibitor control samples and the absence of pyrazines in inhibitor-containing samples.Natural browning inhibitors, that is Rosmarinic acid and Epigallocatechin gallate, can be added to food items to inhibit browning over a prolonged period of storage in order to increase product shelf stability. The concentrations of the inhibitors require optimization since a pro-oxidant effect and increased browning will occur at high levels.