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In this study, mixed starter cultures of yeast and lactobacilli were used for type I sourdough bread making to evaluate their ability to improve bread quality and increase the amount of flavor volatiles. Kazachstania humilis, Saccharomyces cerevisiae, Wickerhamomyces anomalus, and Lactobacillus sanfranciscensis DSM20451T and Lactobacillus sakei LS8 were used in different combinations to ferment wheat sourdough. S. cerevisiae produced the highest amount of CO2 among all strains and thus enhanced bread volume and crumb texture. S. cerevisiae also increased the free thiol level in bread dough, and this study confirms that thiol accumulation was not strongly related to the content of the glutenin macropolymer (GMP) or bread volume. The role of thiol exchange reactions on bread quality differs between long fermentation sourdough and straight dough with baker’s yeast only. The influence of different starter cultures on wheat sourdough bread volatiles was established by using head space solid-phase microextraction and gas chromatography/mass spectrometry analysis (SPME-GC/MS). The sourdough breads fermented with a combination of lactobacilli and yeast had a more complex profile of volatiles, particularly with respect to esters.

In herbal markets, an overwhelming majority the D. officinale are sold in spiral or spring form, and this kind of product would lead to the incomplete release of some nutrients. To increase the bioaccessibility of D. officinale, we report a method of pulverisation treatments including general and superfine grinding to reduce the particle size. In comparison with coarse D. officinale, the superfine ground D. officinale with particle sizes of <18 lm resulted in significant higher bulk density, better flowability and greater hydration properties. The protein and polysaccharide solubility of D. officinale increased significantly as its particle size decreased. The extract of D. officinale with a particle size of <18 lm showed that highest total phenolic and total flavonoid contents accompanied with the best antioxidant activity through all antioxidant assays compared with coarse ground D. officinale and D. officinale products.Superfine grinding of Dendrobium officinale Q. Meng et al.1441 † Span was determined by the equation: span = (d (90) À d (10) )/d (50) . ‡ Values are means AE standard deviation of three replications. § Means values in the same column with different letters are significantly different (P < 0.05).

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A new type of glucose‐responsive hydrogel with rapid response to blood glucose concentration change at physiological temperature has been successfully developed. The polymeric hydrogel contains phenylboronic acid (PBA) groups as glucose sensors and thermo‐responsive poly (N‐isopropylacrylamide) (PNIPAM) groups as actuators. The response rate of the hydrogel to environmental glucose concentration change was significantly enhanced by introducing grafted poly(N‐isopropylacrylamide‐co‐3‐acrylamidophenylboronic acid) [poly(NIPAM‐co‐AAPBA)] side chains onto crosslinked poly(NIPAM‐co‐AAPBA) networks for the first time. The synthesized comb‐type grafted poly(NIPAM‐co‐AAPBA) hydrogels showed satisfactory equilibrium glucose‐responsive properties, and exhibited much faster response rate to glucose concentration change than normal type crosslinked poly(NIPAM‐co‐AAPBA) hydrogels at physiological temperature. Such glucose‐responsive hydrogels with rapid response rate are highly attractive in the fields of developing glucose‐responsive sensors and self‐regulated drug delivery systems. Copyright © 2008 John Wiley & Sons, Ltd.

Debate on the hazards of advanced glycation end products (AGEs) in food has continued for many years as a result of their uncertain bioavailability and ability to bind to their receptors (RAGEs) in vivo. There are increasing evidence that free and bound AGEs have many differences in gastrointestinal digestion, intestinal absorption, binding with RAGEs, in vivo circulation, and renal clearance. Therefore, this paper compares these aspects between free and bound AGEs by summarizing the available knowledge. On the basis of the current knowledge, we conclude that it is time to differentiate free AGEs from bound AGEs in food in future studies, because they vary in many aspects that are closely related to their influence on human health. Several perspectives were proposed at the end of this review for further exploring the difference between free and bound AGEs in food.

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