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Beer quality generally diminishes over time as staling compounds accumulate through various oxidation reactions. Here, we show that refermentation, a traditional practice where Saccharomyces cerevisiae cells are added to beer prior to bottling, diminishes the accumulation of staling aldehydes. However, commonly used beer yeasts only show a limited lifespan in beer. Using high-throughput screening and breeding, we were able to generate novel S. cerevisiae hybrids that survive for over a year in beer. Extensive chemical and sensory analyses of the two most promising hybrids showed that they slow down the accumulation of staling aldehydes, such as furfural and trans-2-nonenal and significantly increased beer flavor stability for up to 12 months. Moreover, the strains did not change the original flavor of the beer, highlighting their potential to be integrated in existing products. Together, these results demonstrate the ability to breed novel microbes that function as natural and sustainable anti-oxidative food preservatives. ispartof: FOOD CHEMISTRY vol:398 ispartof: location:England status: published

Plastic pollution, more specifically from food packaging and containers which account for the largest share of 36% of current plastic production, is one of the greatest threats to the natural environment and human health. Thus, the development of alternative renewable plastics are needed to complement a circular economy and reduce resource depletion. Seaweeds have been known to possess good film forming properties ideal for bioplastic production, and Sargassum natans-an invasive brown seaweed which has been inundating the shores of the Caribbean, has been shown to be an excellent candidate. This study presents, for the first time, the development of a novel optimized biodegradable alginate composite bioplastic as an alternative to traditional plastic packaging. The optimization process was carried out using Response Surface Methodology (RSM) resulting in a formulation of 6 wt% alginate, 0.263 wt% starch, 0.35 wt% CMC, 0.065 g/g sorbitol and 0.025 g/g PEG 200- with ultra-high oxygen barrier (OP - 0.2 cm3 μm m−2 d−1 kPa−1), good water vapor barrier (WVP - 2.18 × 10−12 g m/m2 s Pa) and high tensile modulus ( - 3.93 GPa)- with no migration of additives into a simulated aqueous food system in 10 days. Furthermore, composite films were found to fully degrade in 14 days and possessed better OP, higher WVP and comparable material properties to HDPE, PET and PLA. Ultimately, our results support alginate composite films as a viable alternative for food packaging best fitted for low moisture environments-encouraging the use of renewable materials for packaging innovation and supporting UNSDGs.

Streptomycin (STR) and dihydrostreptomycin (DSTR) are the typically encountered aminoglycoside (AMG) residues in honey. For AMG analysis, studies in literature involve impractical and expensive applications such as ion-pairing chromatography, immunoassays, pre and post column derivatizations, or SPE approaches. Pre -treatments of these methods are toilsome and costly. Herein, one-pot, aqueous in-situ derivatization method was presented as a superior protocol. Time and cost-efficient UHPLC-MS/MS method has been developed, and practical sample preparation was introduced. Satisfactory results were reported in method verification studies. The mean recovery values were 102.6% for STR and 101.3% for DSTR. Average values between 1.5% and 9.9% RSDs were found at intra and inter-day precisions. CC alpha (5.7 and 5.8 mu g/kg) and CC beta (6.2 and 6.4 mu g/kg) values were calculated for STR and DSTR respectively. AMG residues were found in 29 out of 110 analyzed samples using validated method. Described novelty enabled comprehensive analysis in an inexpensive and straightfor-ward manner.

Cassava (Manihot esculenta) is the most important staple food crops grown in Nigeria. This study determined the phytochemical, proximate and mineral contents of cassava leaves and nutritive value of associated arthropod pests. Phytochemicals, proximate, mineral and vitamin contents of samples were analyzed using the method of Association of Official Analytical Chemists. Results showed high amounts of crude protein, crude fat, moisture content, carbohydrate and mineral content in all arthropod insects examined. The highest quantity of Ca (1152.84±0.67 mg/100g) was obtained in ABF4 followed by ABF5 (1148.72±1.09 mg/kg). The lowest phenol content of 0.10±0.00 ppm was obtained in the cassava branch. The leaf recorded the highest phenol value of 0.74±0.01 ppm. Alkaloid had the highest value of 3.51±2.45ppm in Manihot esculenta branch. The highest crude protein and crude fat values of 3.41±0.13 % and 4.83±0.02 % were obtained in ABF5. Vitamin C was found in very high quantities compared to the other types of vitamins examined in this work. The highest Vitamin C content of 34.930±0.136 mg/100g was obtained. Cassava leaves and the arthropod pests are good sources of nutrients. Cassava leaves could also be used as an antimicrobial agent.

BACKGROUND: Rye (Secale cereale L.) is, second to wheat (Triticum aestivum L.), the most common cereal used for producing bread. Rye‐based breads are of great interest because of their high dietary fiber and lysine contents and because of their health effects. However, the bread‐making performance of rye flour is inferior to that of wheat flour. FINDINGS: This review summarizes the current knowledge about the major rye constituents (starch, proteins, and arabinoxylans), their role during bread making, and the potential health implications of rye bread consumption. Rye proteins play only a minor role during bread making, but their exact role remains insufficiently explored. In contrast to wheat proteins, they lack the ability to form a network with good gas‐retaining properties. The rye bread crumb structure is partly attributed to its starch and arabinoxylan polysaccharides. Both bind a lot of water, form networks, and bring about the rye bread structure. CONCLUSIONS: Nevertheless, a better understanding of the role of rye starch, proteins, and arabinoxylans, their interactions, and their impact on dough structure or product quality still needs further exploration. In terms of health effects, EFSA has acknowledged that rye fiber contributes to normal bowel function. There are also indications that rye bread consumption has a number of positive effects such as reducing the risk of colon cancer and hunger feelings and cholesterol‐lowering effects. However, although beneficial health effects of rye‐bread consumption are shown, more research is needed. SIGNIFICANCE AND NOVELTY: A literature search with the terms “rye” and “review” in Web of Science in April 2020 resulted in only six manuscripts. Therefore, this review summarizes the current knowledge about the major rye constituents (starch, proteins, and arabinoxylans), their role during bread making, and the potential health implications of rye bread consumption. ispartof: CEREAL CHEMISTRY vol:97 issue:4 pages:739-754 status: published

This study was aimed to characterize Gracilaria lemaneiformis polysaccharides and evaluate their protective effects on Lipopolysaccharide-induced injury in IEC-6 cells. The G. lemaneiformis polysaccharide was degraded by UV/H2O2 treatment and purified to three fractions named GLP-1.0 M, GLP-1.4 M and GLP-1.6 M. The purified fractions were mainly composed of galactose, glucose and xylose. The structural analysis showed that GLP-1.6 M was a typical sulfated red alga polysaccharide containing the linear backbone of β-(1 → 3)- and α-(1 → 4)-linked galactosyl residues, anhydro-galactose units. In the Lipopolysaccharide-induced IEC-6 cells model, GLP-1.6 M exerted the strongest in vitro anti-inflammatory activity by inhibiting the release and expressions of tumor necrosis factor-α, interleukin-6 and interleukin-1β by 89.93%, 67.82% and 38.06%, respectively. Meanwhile, GLP-1.6 M enhanced the intestinal barrier function via up-regulating the expressions of tight junctions and mucin. Therefore, the purified polysaccharide from G. lemaneiformis could be a promising candidate for maintaining intestinal health in the food and pharmaceutical industries. ispartof: FOOD CHEMISTRY-X vol:12 ispartof: location:Netherlands status: published

Amylose (AM) and amylopectin (AP) functionality during bread making was unravelled with a temperature-controlled time domain proton nuclear magnetic resonance (TD 1H NMR) toolbox. Fermented doughs from wheat flour containing starches with atypical AP chain length distribution and/or AM to AP ratio, or supplemented with Bacillus stearothermophilus α-amylase (BStA) were analyzed in situ during baking and cooling. The gelatinization temperature of starch logically depended on AP crystal stability. It was lower when starch contained a higher portion of short AP branches and higher when starch had higher AP content. During cooling, the onset temperature and extent of AM crystallization were positively related to starch AM content. BStA use resulted in slightly weakened starch networks and increased the starch polymers' mobility at the end of baking. That proton distributions evolved in a way corresponding to starch characteristics supports the suggested interpretation of NMR profiles during baking and cooling. ispartof: FOOD CHEMISTRY vol:295 pages:110-119 ispartof: location:England status: published

Background and objectives Compared to wheat bran, less information on physicochemical characteristics and health-related effects is available for bran from other cereals and results are often confounded by residual endosperm. Therefore, the objective of this study was to compare structure and composition of endosperm-depleted bran of wheat, rye, oat, and maize, and link these characteristics to fecal fermentation characteristics. Findings Compared to wheat, endosperm-depleted rye bran contained twice the amount of fructan (8.0% dm) and water-extractable arabinoxylan (1.4% dm). Oat bran had a more open structure and was rich in (1,3:1,4)-beta-glucan (17.0% dm). For rye and oat bran, and to a lesser extent wheat bran, fermentation with fecal microbiota resulted in short chain fatty acid production, with full metabolization of fructan and beta-glucan after 2 and 24 hr of fecal fermentation, respectively. For maize bran, a less accessible structure containing over 70% of arabinoxylan and cellulose was coupled to a lower degree of fecal fermentation. Conclusion Removal of endosperm as a confounding factor when studying bran properties allowed us to obtain more accurate estimates of the composition, structure, and some physicochemical characteristics of bran of wheat, rye, oat, and maize. Bran fecal fermentation characteristics were mainly determined by composition and to a lesser extent by accessibility of the structure. Significance and novelty This is the first study that compares composition, structure, and fecal fermentation characteristics of wheat, rye, oat, and maize bran, after eliminating endosperm as a confounding factor. The knowledge obtained will allow a more goal-oriented choice of bran type for incorporation into food products, depending on targeted physiological effects and nutritional impact.

A generic extraction and UHPLC-Q-Orbitrap™-HRMS method was developed for four insect species (mealworm, grasshopper, house cricket and black soldier fly) analyzing a large spectrum of organic chemical contaminants, including pesticides (n = 25), (veterinary) drugs (n = 29), and mycotoxins (n = 23). To prove the method as 'fit-for-purpose', a successful validation was performed, both qualitatively, by determining the screening detection limit (SDL), selectivity and specificity, as well as semi-quantitatively, by assessing the within-day precision (relative standard deviation (RSD)) and recovery. For both the mealworm, grasshopper, house cricket and black soldier fly, 64, 61, 59 and 62 compounds were detected at the respective SDL levels (1-100 μg kg-1), predominantly below existing maximum residue limits for other edible matrices. Mean recoveries ranged between 70% and 120% and RSD-values were in line with European regulations (CD 2002/657/EC; SANCO). Finally, the potential of the screening methodology was demonstrated on real insect samples, revealing minor to no contamination. ispartof: FOOD CHEMISTRY vol:293 pages:187-196 ispartof: location:England status: published

Considerable effort in the field of periodontal tissue engineering has been expended in the construction of advanced biomatrix for the treatment of periodontal diseases caused by poor oral hygiene, malnutrition, genetic factors, and systemic disorders. With this in mind, the ultimate goal of this investigation is to fabricate sophisticated scaffolds using jellyfish collagen (JC) and aqueous Salvadora persica (Miswak) extracts. Rhizostoma pulmo species JC was isolated and characterized in depth. Miswak was extracted using two different methods. The extraction yield was calculated to be 14.2 ± 0.9 % and 17.1 ± 0.4 % for the Method I and II, respectively. gas chromatography-mass spectroscopy (GC-MS) results revealed the extract to be composed of 1,8-cineole (49.3 %), benzyl nitrile (36.2 %), benzyl isothiocyanate (5.9 %), limonene (2.4 %), eugenol (0.8 %) and palmitic acid (0.3 %). Total phenolic content and antioxidant capacities of the extracts were also determined by spectrophotometrically. Human periodontal ligament fibroblast cells were isolated and expanded. Cell viability on JC and miswak extract-laden JC scaffolds was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. Microarchitectures of the JC, 0.05 and 0.1% miswak extract-laden JC scaffolds and also cellular behaviors on these surfaces were evaluated by scanning electron microscopy (SEM) analysis. This study suggests that miswak extract-laden JC scaffolds would present new opportunities for periodontal tissue engineering.

Animal proteins are widely used because of their good techno-functional (e.g. emulsification) properties. However, the large ecological impact of animal-derived proteins is often debated and therefore alternatives are evaluated in which animal proteins with increased functionality are employed. Amyloid fibrils are a distinct type of protein fibrils characterized by an intermolecular cross β-sheet structure, mostly studied because of concerns regarding their role in certain human diseases. However, they have also been detected in processed food proteins such as heated ovalbumin (OVA) and other egg proteins. Previous work also mentioned superior emulsification properties of amyloid-like fibrils. Here, the effect of different shear conditions during the emulsification of oil in water emulsions stabilized by heated OVA was investigated. Emulsification with intensive shear treatment (using both an ultra-turrax and a microfluidizer) resulted in submicron sized droplets, whilst ultra-turrax only gave rise to rapidly creaming emulsions (>10 μm). Thioflavin T (ThT) fluorescence, used as an indicator of cross β-sheets, did significantly increase for submicron emulsions, whereas supermicron emulsions showed a similar fluorescence as the aqueous phase used for emulsification. The increase in ThT fluorescence in submicron emulsions was in line with a higher amount of larger fibrillar structures, which showed high ThT fluorescence, measured using size exclusion-HPLC and transmission electron microscopy images. Similar observations were also made for unheated OVA, suggesting that high-shear emulsification induced amyloid-like fibril formation. In contrast, shearing of aqueous solutions without the creation of interfaces did not show increased fibril formation. Therefore, it is claimed that the large specific surface area induced amyloid-like fibril formation or maturation as a result of a better interaction between hydrophobic amyloid-like fibril fragments. In this work, we were able to characterize the protein fibrillar structures present in emulsions by considering commonly used techniques for the study of fibril formation. This creates opportunities towards the implementation of these protein mixtures in food applications.

In this study, the effect of ripening stage (R), cultivar (C), bunch type (T), and location (L) on the variability of provitamin A carotenoids (pVACs) in 16 plantain cultivars grown in Cameroon and Gabon was investigated. For the sixteen plantain cultivars, fruits were collected at stages 1 (unripe), 5 (ripe), and 7 (overripe) from three different bunch types (French, False Horn, and True Horn) across 13 locations in Cameroon and Gabon. For all cultivars, the highest concentration of carotenoids was found in ripe pulp (p < 0.05). For bunch type, a higher level of pVACs was observed in the French type compared with the False Horn and True Horn types at all ripening stages. In addition, the concentration of pVACs at each ripening stage varied greatly across locations. In both countries, the interaction between the four factors, particularly between R × C, R × T, R × L, R × C × L, and R × T × L, contributed significantly (p < 0.05) to the variability of pVACs in plantain. Daily consumption of 100 g of ripe plantain could meet 36.2–101.7 % of the dietary reference intakes (DRIs) for children 1–5 years old, 20.7–58.1 % for adult women, and 16.1–45.2 % for adult men. These findings can serve as a guide to reducing vitamin A deficiency (VAD) in Africa. ispartof: Journal Of Food Composition And Analysis vol:94 pages:1-17 status: published

In this article, the chemical compounds, antimicrobial and antioxidant activity of the volatile oil from leaves of Olea europaea L. cultivar from Turkey (Ayvalık) has been studied. The essential oil was provided with a Clevenger apparatus and analyzed by GC-MS/FID. This analysis leads to the detection of 42 compounds representing 99.59±1.15% of the total oil. The major constituents were a-pinene (9.82±0.33%), benzylalcohol (8.83±0.27%), phenethylalcohol (8.52±0.25%), 2-monopalmitin (8.13±0.28%), palmitic acid (5.53±0.41%), octadecanoic acid 2,3-dihydroxypropylester (5.84±0.42%), phytol (4.22±0.17%), and benzaldehyde (4.21±0.38%). The antimicrobial activities of the dried leaves essential oils were assessed against seven bacterial and four fungal strains. Significantly, the essential oil has an efficient antibacterial activity toward to the bacterial strains such as Bacillus cereus ATCC 14579, Candida albicans ATCC 10231, Enterococcus faecalis ATCC 29212 and Klebsiella pneumoniae ATCC 13883. The olive a leaf essential oils showed significant antimicrobial and antioxidant effects. This study gives more knowledge for the development of this crucial therapeutic plant.

The emulsifying and emulsion stabilizing potential of 13 citrus pectin (CP) derived samples exhibiting differences in degree of methylesterification (DM, 11–74%) and molecular weight (Mw, 2.5–151 kDa) was studied using an integrated multimethod approach, which involved the evaluation of structural and physicochemical properties of each pectin sample, as well as detailed storage stability studies of pectin-containing emulsions. It was observed that all CP derived samples had a high negative ζ-potential, depending on the DM of the sample and pH of the medium. Furthermore, they exhibited an enhanced interfacial activity at pH 6.0 compared to pH 2.5. Moreover, significant differences in viscosity were observed between CP derived samples of high (>62 kDa) and low ( 62 kDa) CP containing emulsions at pH 2.5, regardless pectin DM. On the contrary, flocculation and coalescence were observed at early stages in the 20 low Mw CP containing emulsions, indicating destabilization. Likewise, creaming and phase separation of the latter emulsions was evident from the day of emulsion preparation. Generally, low Mw (

We examined the similarities and differences of the binding behavior of lysozyme (lys) with pectin varying in local charge density (blockwise distribution and statistical distribution of methoxyl groups, BP and SP) and similar degree of methoxylation (DM). The interaction at ionic strength I = 0.01 and pH 5.1 was found to be mainly electrostatic, associated with an exothermic enthalpy change. BP which is more inclined to self-association binds lys forming strongly associated complex particles with average sizes much larger (10–20 μm) than that of SP. The latter formed with lys small (0.6–3 μm) complex particles or liquid droplets depending on DM. The critical Iset and pHset values for BP/lys systems, above which complexes do not form, are not sensitive to DM (approximately 0.1 and 11.5 respectively), whereas for SP/lys systems the critical Iset and pHset values decrease significantly with increasing DM. The effect of I on complexation (CP) of lys with BP and SP has a nonmonotonic character. The distribution of BP and SP within the complex particles is irregular and is different for pectin with low and high DM values. The binding constant and stoichiometry ratio (lys/pectin) of the systems with SP are slightly higher than those of BP at the same DM, and these values decrease sharply (50 times) with increasing DM. The large positive changes in entropy in SP/lys systems suggest that the interactions in these systems tend to be more hydrophobic in character at high DM. On the other hand, with BP, a negative enthalpy change, especially for pectin with low charge, suggests the formation of a large quantity of hydrogen bonds or van der Waals interactions during CP. ispartof: FOOD HYDROCOLLOIDS vol:99 status: published

The impact of Aqualysin 1 (Aq1), the thermo-active peptidase of Thermus aquaticus, on wheat albumin, globulin, gliadin and glutenin proteins during heat treatment of wheat dough and bread baking was examined. The level of protein extractable in sodium dodecyl sulfate containing medium under non-reducing conditions (SDS-EP-NR) from wheat dough decreases upon heating to a lesser extent when Aq1 is used than in control experiments. The higher SDS-EP-NR level is caused by the release by Aq1 of peptides from the repetitive gluten protein domains during baking. These peptides are also extractable from bread crumb with salt solution. The resultant thermoset gluten network in bread crumb is mainly made up by protein from non-repetitive gluten domains. ispartof: Food Chemistry vol:295 pages:599-606 ispartof: location:England status: published

We examined how a particular structural characteristic of pectin, namely its degree of methoxylation (DM), affects its complexation with lysozyme (lys), whereby the phase behavior of the complex system as a whole as well as the aggregation state of the complex phase are considered. Low and medium methoxylated pectins bind lys at pH 5.1 and low ionic strength (I = 0.01) forming highly concentrated gel like complex particles, whereas highly methoxylated pectins undergo liquid/liquid phase separation with lys. “Mother” pectin with DM = 95.1% does not form complexes with lys. Highly charged pectins (low DM) already form complex particles at low pectin/lys weight ratios and have a high yield of the complex phase that consists of relatively large particles. The distribution of pectin within the complex particles has an irregular character for both pectin types. However, whereas for low DM pectin the complex composition reflects that of the mixture, the complex composition with high DM pectin is less sensitive to the mixture composition. Moreover, at low DM, the maximum complexation corresponds to charge neutralization whereas at high DM maximum complexation requires a larger than stoichiometric amount of lys. The minimal I and pH value at which complexation is completely suppressed, decreases with increasing DM of pectin, indicating the presence of electrostatic interactions in all systems. However, the differences in composition of the complexes and the protein/polysaccharide charge ratio at maximal complexation indicate that the exact binding mechanism depends on the pectin DM. ispartof: FOOD HYDROCOLLOIDS vol:94 pages:268-278 status: published

Due to ethical issues and the difficulty in obtaining biological tissues, it is important to find synthetic elastomers that can be used as replacement test media for research purposes. An important example of this is friction testing to understand the mechanisms behind mouthfeel attributes during food consumption (e.g. syrupy, body and clean finish), which requires an oral mimic. In order to assess the suitability of possible materials to mimic oral surfaces, a sliding contact is produced by loading and sliding a hemispherical silica pin against either a polydimethyl siloxane (PDMS), agarose, or porcine tongue sample. Friction is measured and elastohydrodynamic film thickness is calculated based on the elastic modulus of the samples, which is measured using an indentation method. Tests were performed with both saliva and pure water as the lubricating fluid and results compared to unlubricated conditions. PDMS mimics the tongue well in terms of protein adhesion, with both samples showing significant reductions in friction when lubricated with saliva versus water, whereas agarose showed no difference between saliva and water lubricated conditions. This is attributed to PDMS's O Si(CH3)2- group which provides excellent adhesion for the saliva protein molecules, in contrast with the hydrated agarose surface. The measured modulus of the PDMS (2.2 MPa) is however significantly greater than that of tongue (3.5 kPa) and agarose (66–174 kPa). This affects both the surface (boundary) friction, at low sliding speeds, and the entrained elastohydrodynamic film thickness, at high speeds. Utilising the transparent PDMS sample, we also use fluorescence microscopy to monitor the build-up and flow of dyed-tagged saliva proteins within the contact during sliding. Results confirm the lubricous boundary film forming nature of saliva proteins by showing a strong correlation between friction and average protein intensity signals (cross correlation coefficient = 0.87). This demonstrates a powerful method to study mouthfeel mechanisms.

In this study, the changes in phenolic composition, total phenolic content, and antioxidant capacity of tarhanas supplemented with oat flour (OF) at the levels of 20-100% (w/w) after three drying treatments (sun-, oven-, and microwave drying) were investigated. A total of seventeen phenolic standards have been screened in tarhanas, and the most abundant flavonol and phenolic acid compounds were kaempferol (23.62 mg/g) and 3-hydroxy-4-metoxy cinnamic acid (9.60 mg/g). The total phenolic content amount gradually increased with the addition of OF to tarhana, but decidedly higher total phenolic content was found in samples oven dried at 55 °C as compared with other methods. The microwave- and oven dried tarhana samples showed higher TEACDPPH and TEACABTS values than those dried with the other methods, respectively, in higher OF amounts. Consequently, oven- and microwave-drying can be recommended to retain the highest for phenolic compounds as well as maximal antioxidant capacity in OF supplemented tarhana samples. © 2015 Elsevier Ltd.

Excess dietary sodium is a modifiable cause of high blood pressure. The World Health Organization has targeted a 30 % reduction in mean population sodium consumption by 2025. In 2008, members of the International Food and Beverage Alliance (IFBA) made commitments to lower sodium content in their products. The aim of this study was to determine recent changes in sodium levels between 2013 and 2017 in foods and beverages produced by companies that are IFBA members (n = 10) and non-IFBA members (n = 6) that were included in the 2018 Global Access to Nutrition Index operating in Australia. Independent Samples t-tests and Mann Whitney U tests were used to test the differences in sodium levels. There was no clear difference in sodium content between 2013 and 2017 detectable for the IFBA members (mean difference 17 mg/100 g, 95 % confidence interval (CI), –82 to +48; p = 0.612; median difference 27 mg/100 g, p = 0.582). For the non-IFBA companies there was a decrease in median sodium content (−30 mg/100 g; P = 0.002) but not mean sodium content (−52 mg/100 g, 95 % CI −106 to +3; p = 0.064). Sodium reduction in IFBA companies appear to have had slow progress in Australia. Stronger implementation and monitoring programs are needed to drive industry action.

Gas cell stabilization in dough by its aqueous phase constituents is arguably more important in non-wheat than in wheat dough due to weaker protein networks in the former. Dough liquor (DL), a model for the dough aqueous phase, was isolated from fermented wheat, rye, barley, and oat doughs by ultracentrifugation. DL composition (protein, lipid, arabinoxylan, β-glucan) and air/water interfacial functionality [foaming, viscosity, surface tension, surface dilatational modulus (E)] were related to bread quality. Poor foaming and low E of wheat DL were ascribed to lipids and proteins co-occurring at the interface. Nonetheless, the presence of a gluten network resulted in high-quality wheaten breads. Homogeneous and heterogeneous crumb structures of rye and barley breads, respectively, were attributed to high and low E values of their respective DLs. High lipid content and low surface tension of oat DL indicated a lipid-dominated interface, which may explain the heterogeneous crumb structure of oat breads. ispartof: FOOD CHEMISTRY vol:264 pages:126-134 ispartof: location:England status: published

The thermo-active serine peptidase aqualysin 1 (Aq1) of Thermus aquaticus was applied in bread making to study the relative contribution of thermoset gluten to bread crumb texture. Aq1 is active between 30 °C and 90 °C with an optimum activity temperature of around 65 °C. It is inhibited by wheat endogenous serine peptidase inhibitors during dough mixing and fermentation and starts hydrolyzing gluten proteins during baking above 80 °C when the enzyme is no longer inhibited and most of the starch is gelatinized and contributes to structure formation. Aq1 activity reduced the molecular weight of gluten proteins and significantly increased their extractability in sodium dodecyl sulfate containing medium. While it had no impact on the specific bread volume and only limited impact on hardness, cohesiveness, springiness, resilience and chewiness, it impacted bread crumb coherence. We conclude that starch has a greater impact on crumb texture than thermoset gluten. ispartof: FOOD CHEMISTRY vol:264 pages:118-125 ispartof: location:England status: published

This study outlines the determination of total elemental contents, time-dependent extractabilities, and bioaccessibilities of Mg, Mn, and Fe from nine tea samples, including black, earl grey, and green teas, using inductively coupled plasma mass spectrometry. Leachabilities and bioaccessibilities were evaluated using samples infused for 2, 5, and 10 min, and bioaccessible levels were determined after in vitro enzymatic digestion. Lemon juice, sugar, milk, calcium, and tannic acid were studied as additives, and found to increase or decrease the bioaccessibilities from black tea infusions. Drinking one cup of tea provided 0.16%, 0.01%, and 0.10% of the recommended dietary allowance of Mg for black, earl grey, and green teas infused for 2 min, respectively. The equivalent levels were 11%, 6%, and 7% for Mn, and 0.05%, 0.02%, and 0.02% for Fe in the same samples, respectively. Therefore, Mn was found to be the most bioaccessible element resulting from tea consumption, reaching 17%–24% of the recommended daily allowance in the 10-min infusion. Moreover, lemon juice was found to increase the bioaccessibility of Mn by up to 3.4-fold, even in tea samples infused for 2 min.

The recently described new experimental tool called Drop and Bubble Micro Manipulator (DBMM) has been applied to studies of the stability of protein covered bubbles against coalescence. Among the available protocols the time interval between the moment of bubble contact to the moment of coalescence of two contacting bubble is determined for different β-Lactoglobulin (BLG) concentrations and different ageing times. A threshold concentration of BLG is needed to prevent immediate coalescence. The longer the ageing time above this threshold concentration of BLG is the longer is the lifetime of the liquid film between the bubbles. The adsorbed amount of BLG was determined as a function of time and concentration and correlates with the observed coalescence behaviour of the contacting bubbles. Refereed/Peer-reviewed

Commercially available single origin chocolates (n = 139) were analysed by ICP-MS to identify the potential of elemental fingerprinting for tracing cacao origin in chocolate and to compare chocolate composition relative to trace metal limits. Cadmium (Cd) concentrations exceeded the EU limit of 0.80 mg kg−1 in 16 samples, all produced with cacao from South or Central America. Six samples contained lead (Pb) concentrations >0.10 mg kg−1, the limit of the Codex Alimentarius for edible fats. Increasing cacao content was associated with increased element concentrations for most elements, indicating cacao as the main source of minerals and trace elements. Significant differences in elemental composition between origins (P value ≤ 0.05) were found for Ba, Cd, Mo and Sr. Classification and regression tree analysis (CART) resulted in a decision tree that could effectively classify chocolate samples by cacao origin continent (overall misclassification rate 23%) based on the concentrations of five elements (Ba, Cd, Mo, Sr and Zn). Samples of South America were classified based on their Cd concentration, indicating the geogenic origin of Cd.

The availability of fresh water and the quality of aquatic ecosystems are important global concerns, and agriculture plays a major role. Consumers and manufacturers are increasingly sensitive to sustainability issues related to processed food products and drinks. The present study examines the production of sugar from the growing cycle through to processing to the factory gate, and identifies the potential impacts on water scarcity and quality and the ways in which the impact of water use can be minimised. We have reviewed the production phases and processing steps, and how calculations of water use can be complicated, or in some cases how assessments can be relatively straightforward. Finally, we outline several ways that growers and sugar processors are improving the efficiency of water use and reducing environmental impact, and where further advances can be made. This provides a template for the assessment of other crops. (c) 2013 Society of Chemical Industry

Increasingly abundant food fraud cases have brought food authenticity and safety into major focus. This study presents a fast and effective way to identify meat products using rapid evaporative ionization mass spectrometry (REIMS). The experimental setup was demonstrated to be able to record a mass spectrometric profile of meat specimens in a time frame of

A Citrobacter strain (WYE1) was isolated from a UK soil by enrichment using the glucosinolate sinigrin as sole carbon source. The enzyme myrosinase was purified using a combination of ion exchange and gel filtration to give a pure protein of approximately 66 kDa. The N-terminal amino acid and internal peptide sequence of the purified protein were determined and used to identify the gene, which, based on InterPro sequence analysis, belongs to the family GH3, contains a signal peptide, and is a periplasmic protein with a predicted molecular mass of 71.8 kDa. A preliminary characterization was carried out using protein extracts from cell-free preparations. The apparent KM and Vmax were 0.46 mM and 4.91 mmol dm(-3) min(-1) mg(-1), respectively, with sinigrin as substrate. The optimum temperature and pH for enzyme activity were 25 °C and 6.0, respectively. The enzyme was marginally activated with ascorbate by a factor of 1.67.

Mass transfer of solutes like salt, moisture and metabolites, is very important for the final quality of cheese, through the control of the brining and ripening processes. Numerous studies have reported salt and water transfer properties in cheese, but few have dealt with other solutes. Moreover, most diffusion coefficients have been obtained by macroscopic and destructive methods. We developed the fluorescence recovery after photobleaching (FRAP) technique on a confocal microscope to measure in situ and at the microscopic scale diffusion properties inside cheese. A model matrix based on ultrafiltrated milk was used. FITC-dextran molecules were chosen as models of migrant solutes. Diffusion coefficients were estimated with a modelling approach which takes into account diffusion during the bleach phase. The FITC-dextrans (4 and 20 kDa) were able to migrate in the proteinic network, but their mobility was 2.2-3 times lower than in water, depending on their size.

BACKGROUND: Pasture (fresh or conserved as hay/haylage) forms the basis of most equid diets and contains varying amounts (0 to ≥ 200 g kg−1 dry matter (DM) or more) of fructans. Over-consumption of fructan is associated with the onset of laminitis in equids, an agonizing condition that may necessitate euthanasia. To enable appropriate dietary management of animals susceptible to laminitis, it is essential that fructans can be properly quantified in fresh and conserved pasture. For research purposes, fructans are frequently quantified by high-performance liquid chromatography (HPLC), but these methods are costly for routine screening. However, an inexpensive colorimetric method for measuring fructans in human foods is commercially available. The aim here was to determine the suitability of the commercially available colorimetric method for determining the fructan content of pasture grasses for horses. RESULTS: Pasture grasses (Phleum pretense, Festuca rubra, Dactylis glomerata, Lolium perenne) managed for grazing (sampled from April to November) and a further set managed for conservation (sampled in July) were analysed for fructan content by HPLC and the colorimetric technique. HPLC values ranged from 83 to 299 g fructan kg−1 DM (mean 154); corresponding colorimetric values were 5-238 g fructan kg−1 DM (mean 82). Discrepancies in values between the two methods varied with time of sampling and plant species. Comparison of selected samples before and after incubation with the fructan hydrolases used in the colorimetric method revealed incomplete fructan hydrolysis from the pasture grasses, resulting in underestimates of their fructan content. CONCLUSION: The colorimetric technique was not a reliable substitute for HPLC to quantify the fructan content of pasture grasses. Copyright © 2012 Society of Chemical Industry

Sulphur volatiles are major factors in the perceived aroma of grapefruit juice, GFJ. The objective of this study was to develop a procedure to concentrate, separate, identify and quantify the major volatile sulphur compounds, VSC's, in grapefruit juices. SPME parameters such as headspace atmosphere, fibre coating, extraction time and temperature were evaluated. High resolution capillary CC using ZB-5, DB-Wax and PLOT columns coupled with pulsed flame photometric detection, PFPD, were employed for separation and detection. Thirteen sulphur volatiles were identified including; hydrogen sulphide, sulphur dioxide, methanethiol, dimethyl sulphide, carbon disulphide, dimethyl disulphide, 2-methyl thiophene, 3-methyl thiophene, methional, dimethyl trisulphide, 3-mercaptohexylacetate, 2,8-epithio-cis-p-menthane and 1-p-menthene-8-thiol. Five additional VSC's were tentatively identified. Canned reconstituted GFJ had more total sulphur volatiles and a greater number than fresh GFJ. Hydrogen sulphide comprised over 80% of total sulphur volatiles in fresh GFJ but only 5% in canned GFJ. University of Florida Alumni Fellowship Foundation

Sprout damage which results in poor breadmaking quality due to enzymatic activity of alpha-amylase is one of the important grading factors of wheat in Canada. Potential of near-infrared (NIR) hyperspectral imaging was investigated to detect sprouting of wheat kernels. Artificially sprouted, midge-damaged, and healthy wheat kernels were scanned using NIR hyperspectral imaging system in the range of 1000-1600 nm at 60 evenly distributed wavelengths. Multivariate image analysis (MVI) technique based on principal components analysis (PCA) was applied to reduce the dimensionality of the hyperspectral data. Three wavelengths 1101.7, 1132.2, and 1305.1 nm were identified as significant and used in analysis. Statistical discriminant classifiers (linear, quadratic, and Mahalanobis) were used to classify sprouted, midge-damaged, and healthy wheat kernels. The discriminant classifiers gave maximum accuracy of 98.3 and 100% for classifying healthy and damaged kernels, respectively. Refereed/Peer-reviewed

BACKGROUND: Tea (Camellia sinensis (L.) O. Kuntze) is a perennial leaf harvested crop. It requires more nitrogen than most other crops and preferentially utilises NH4+ to NO3− when both are available in the soil. It is expected that slow release fertilisers coupled with a nitrification inhibitor could improve the N use efficiency and simultaneously reduce environmental pollution. In this study, three slow release fertilisers were developed and tested: CaMg phosphate coated urea with dicyandiamide (DCD) as a nitrification inhibitor and polyolefin coated urea with and without DCD. The main aim was to compare the nitrogen release dynamics and transformation of these fertilisers and their effects on tea yield and quality. RESULTS: The results showed that the coatings significantly slowed N release and kept mineral N in soils at a higher concentration for a longer time compared to uncoated urea. Polyolefin was a superior coating to CaMg phosphate. DCD was an effective nitrification inhibitor and significantly reduced the ratio of nitrate to total mineral N in a highly acidic tea soil. The 15N use efficiency was 29% where uncoated fertiliser was applied and 46% where polyolefin coated fertiliser with DCD was applied. The application of slow release fertilisers increased the chlorophyll content in mature leaves and enhanced the uptake of mineral elements by tea plants. Bud sprouting, shoot growth and mature leaf longevity were significantly improved, resulting in higher biomass of tea plants. Slow release fertilisers increased the yield of shoots by 51–143% (mean, 106%) in a pot experiment and 4–14% (mean, 9%) in a field experiment compared to uncoated urea. Tea quality parameters, especially free amino acids, were also significantly increased. CONCLUSION: Slow release fertilisers, especially polyolefin coated urea with DCD could significantly increase the N use efficiency and improve tea growth. Their uses in tea fields not only improved the profit margin, but possibly reduced environmental pollution. Copyright © 2008 Society of Chemical Industry

To evaluate the potential benefits and risks associated with tea consumption it is important to identify the constituents of this beverage. Levels of some minerals, caffeine and catechins in green tea samples commercialized in Portugal were evaluated. Potassium is the metal present in larger amount (92-151 mg/l). The content of sodium, calcium, fluoride, aluminium, manganese and iron were 35-69, 1.9-3.5, 0.80-2.0, 1.0-2.2, 0.52-1.9, 0.020-0.128 mg/l, respectively. Chromium and selenium were not detected. The resulting data showed considerable variability in catechins content. The levels of epigallocatechin gallate (EGCG) ranged from 117 to 442 mg/l, epicatechin 3-gallate (EGC) from 203 to 471 mg/l, epigallocatechin (ECG) from 16.9 to 150 mg/l, epicatechin (EC) from 25 to 81 mg/l and catechin (C) from 9.03 to 115 mg/l. Caffeine contents in the green tea infusions studied were between 141-338 mg/l. Green tea infusions provide significant amounts of catechins and could be an important source of some minerals.

WOS: 000246674800042, PubMed ID: 17488092, Leaves of Vitis vinifera (Fam. Vitaceae) cv. 'Sultani ekirdeksiz' cultivated in Manisa-Alaehir in western Turkey, were processed with or without brine. Fresh, brined, and nonbrined leaves (after being subjected to 3 months of fermentation) were sampled and extracted with distilled water under reflux. Antioxidant, anti-inflammatory, and anti-nociceptive activities of the water extracts were investigated using in vitro and in vivo methods. Free radical scavenging activity (1,1-diphenyl-2-picrylhydrazyl, DPPH center dot assay), iron(III) reductive activity (reducing power activity assay), capacity of inhibition of linoleic acid peroxidation (ferric thiocyanate and thiobarbituric acid method), anti-nociceptive activity (p-benzoquinone-induced abdominal constriction test), and anti-inflammatory activity (carrageenan-induced hind paw edema model) were used to determine biological activities of the extracts. In addition, the contents of total phenolics, flavonoids, and flavonols in the extracts were determined by spectrophotometrical methods. Results were compared with those of ascorbic acid, butylated hydroxytoluene, and gallic acid as reference antioxidants. The extracts of fresh, brined, and nonbrined leaves showed almost the same activity in all antioxidant assays. These extracts inhibited the oxidation of linoleic acid to the same extent as BHT. Compositions of the extracts were analyzed by a reverse phase HPLC-PDA method. The occurrence of hydroxycinnamic acids (e.g., caffeic acid) and flavonoids (e.g., quercetin) was verified in the extracts. The content of total flavonoids as well as quercetin was increased by fermentation.

Concentrations of trans-resveratrol, catechin and epicatechin were analyzed in musts and wines produced from seven red and four white grape cultivars from various wine growing regions of Turkey. Phenolics were quantified using an HPLC method optimized for the separation of wine phenolics. Wine samples contained higher phenolics levels than the corresponding musts. With the exception of Semillion, white wines and musts contained lower concentrations of phenolics than red wines and musts. However, the white cultivar Semillion had the highest concentrations of catechin and epicatechin among all wine and must samples. Semillion wine catechin and epicatechin were 13.7 and 11.8 mg/L, respectively. The highest level of trans-resveratrol among the white cultivars was found in Narince wine (1.93 mg/L). Within the red wine and must cultivars, Bogazkere, Okuzgozu, and Cabernet contained the highest concentrations of flavan-3-ols and trans-resveratrol. Catechin was the major phenolic in all wines and most musts. Epicatechin was the major phenolic in 6 of the 11 must samples, but none of the wine samples. trans-Resveratrol was generally found in lowest concentrations in both wines and musts.

The aim of this study was the modelling, under high pressure, of naringin hydrolysis by naringinase. Response surface methodology (RSM) was used to compare the effects of the selected variables on the bioconversion under study. The combined action of temperature (13-61 degrees C) and pressure (80-216 MPa) on the catalytic activity of naringinase was investigated at pH 4.0 using naringin as the substrate. The choice of experimental domains resulted from preliminary studies. Naringinase activity, for naringin hydrolysis at pH 4.0, could be described by a convex surface with a maximum of 0.13 mM min(-1), at 41 degrees C and 158 MPa. After 1 h of reaction time, reducing sugars production could also be described by a convex surface, with a maximum reducing sugars concentration of 8 mM at 38 degrees C and 168 MPa. The interaction temperature-pressure had a significant effect on both naringinase activity and reducing sugar formation after 1 h. Under the optimized conditions, the naringin hydrolysis by naringinase was evaluated. (c) 2007 Elsevier Ltd. All rights reserved.

Total mercury, cadmium and lead concentrations were measured in black scabbard fish (Aphanopus carbo), caught off Madeira and the Azores archipelagos (Portugal). The metal contents were expressed in mg kg(-1) wet weight. The mean mercury levels in liver were 4.50 and 2.37 whereas, in skin, such values were 0.59 and 0.36 (Madeira and Azores, respectively). Onaverage, the muscle content was around 0.9 in fish from both areas. Cadmium maximum levels in muscle and skin were found in Azores samples (0.09 and 0.11, respectively). Mean lead contents in all samples were always below than 0.10. In general, the results obtained did not allow the establishment of any relationship between metal accumulation and fish weight or length. According to the permissible WHO and FAO levels, these results, suggest that this species does not represent a risk for human consumption if the liver is excluded and the edible part consumed with moderation. (c) 2006 Elsevier Ltd. All rights reserved.

Ninety-two black and green table olive samples from the Bursa, Turkey were analyzed. The olives were sampled from 56 brands, four processing methods and three packing types. The concentration of Mg, Cr, Co, Ni, Fe, Cu, Zn, Sn, Cd and Pb were measured by inductively coupled plasma mass spectrometry (ICP-MS). While the most concentrated element was Mg (125.11 +/- 5.02), Co, (0.09 +/- 0.01) had the lowest concentration in tested olive samples. The levels of the ten metals studied are within safe limits. The data here obtained will be valuable in complementing available food composition data, and estimating dietary intakes of heavy metals in Turkey. The metals Mg, Fe, Zn, Sn and Pb presented significant differences (p < 0.05) in content between two types, hence processing method, brand and packing material must influence their content.

Detection of GMO material in crop and food samples is the primary step in GMO monitoring and regulation, with the increasing number of GM events in the world market requiring detection solutions with high multiplexing capacity. In this study, we test the suitability of a high-density oligonucleotide microarray platform for direct, quantitative detection of GMOs found in the Turkish feed market. We tested 1830 different 60 nt probes designed to cover the GM cassettes from 12 different GM cultivars (3 soya, 9 maize), as well as plant species-specific and contamination controls, and developed a data analysis method aiming to provide maximum throughput and sensitivity. The system was able specifically to identify each cultivar, and in 10/12 cases was sensitive enough to detect GMO DNA at concentrations of

The article presents the results of optimization of operation parameters, investigation of analytical characteristics and the abilities of a graphite filter-furnace (FF) atomizer for the direct electrothermal atomic absorption spectroscopy (ET AAS) determination of trace amounts of Mn, As, Pb, Cu, Cd and Zn in some vegetable oils and fats. The effect of pyrolysis and atomization temperatures of the graphite FF atomizer on atomic absorbance values of the listed elements at their evaporation from some organic solutions in the presence of a Pd-Mg chemical modifier (CM) was investigated. For the ET AAS determination of As, Pb, Cd and Zn with Pd-Mg CM, the temperature of the graphite FF atomizer for the pyrolysis step can be raised by 250-350 degrees C. This mode allows to eliminate the background absorption, to increase the sensitivity of the elements to be analyzed and to enhance the total content of vegetable oils or fats in organic solutions up to 0.5 g mL(-1). The obtained limits of quantification for Mn, As, Pb, Cu, Cd and Zn were 0.002, 0.004, 0.004, 0.002, 0.0008, 0.0004 mg kg(-1), respectively. The relative standard deviation (RSD) varied between similar to 3 and 8% and the time of one element determination did not exceed similar to 3-5 min. The reliability of the proposed method was checked using the reference method. A paired Student's t-test showed no significant difference between the results obtained by both methods on a 95% confidence level.

The distribution of aflatoxin M-1 ( AFM(1)) has been studied between curd, whey, cheese and pickle samples of Turkish white pickled cheese produced according to traditional techniques and its stability studied during the ripening period. Cheeses were produced in three cheese-making trials using raw milk that was artificially contaminated with AFM(1) at the levels of 50, 250 and 750 ng/l and allowed to ripen for three months. AFM(1) determinations were carried out at intervals by LC with fluorescence detection after immunoaffinity column clean-up. During the syneresis of the cheese a proportionately high concentration of AFM(1) remained in curd and for each trial the level was 3.6, 3.8 and 4.0 times higher than levels in milk. At the end of the ripening, the distribution of AFM(1) for cheese/whey + brine samples was 0.9, 1.0 and 1.3 for first, second and third spiking respectively indicating that nearly half of the AFM(1) remained in cheese. It has been found that only 2 - 4% of the initial spiking of AFM(1) transferred into the brine solution. During the ripening period AFM(1) levels remained constant suggesting that AFM(1) was quite stable during manufacturing and ripening.

WOS: 000329545900006 Aflatoxin M1 (AFM1) levels in milk and milk products (kasar cheese, tulum cheese, dil cheese, cream cheese, white cheese) consumed in Turkey were determined in this study by using enzyme-linked immunosorbent assay (ELISA). Extraction procedure was optimised to obtain high extraction efficiency. Recovery experiment was also performed to test the suitability of the extraction system and it was observed that % recovery values for AFM1 were higher than 92%. The method used in this study was simple and suitable for the detection of AFM1 in these matrices. Results found from the samples were compared with the requirements of Turkish Food Codex (TFC). As much as 42.16% of cheese samples analysed were contaminated while 61/77 milk samples were found to be contaminated with AFM1 in the range of 0.005-0.410 mu g/L. It was found that five white cheese, one kasar cheese and four milk samples exceeded the criteria of 0.5 g/kg for cheese and 0.05 g/L for milk set by TFC.

Protein adsorption is one of the most complex and intriguing phenomenon in interfacial science. This phenomenon has been addressed in this paper for a short time range using maximum bubble pressure tensiometer. This study presents the issue of negative surface pressure of proteins which has been much of a speculation, with the thermodynamic model. Here beta-lactoglobulin has been studied at different pHs and the experimental results agree with the theoretical model presented. Refereed/Peer-reviewed

Erdoğan, Eyüp (Balikesir Author), Water-distilled essential oil from the crushed fruits of Ferulago confusa Velen, collected from Bursa: Keles-Orhaneli in Turkey, was analyzed by GC and CC/MS. Ninety-one components were identified representing 99.5% of the oil. Cis-chrysanthenyl acetate (37.7%) and a-pinene (36.7%) were characterized as the main constituents. The antibacterial effects of the Ferulago confusa oil were evaluated by using microdilution broth method. The oil showed moderate inhibitory effects on the selected human pathogenic bacteria having MIC values ranging 0.6-2.5 mg/ML.

Complex processes concerning declining concentration of organic matter within pig wastes have been investigated using deuterated phenol (d(5)) and acetic acid (d(4)) over a ten day period. Decomposition rates of products responsible for odours and pollution were also quantified. These products included the volatile fatty acids, phenols and indoles as well as gaseous methane and carbon dioxide. The last two were quantified in the headspace flow to assess methanogenesis and the activity of bacteria. The relative rates of emission, production and bio-decay were calculated as exponential curves showing that acetic acid was lost through emission and bio-decay with half lives of 158 h and 95 h, respectively. Bio-production of acetic acid was very low. The emission rate of methane was 4.0 g m(-3) d(-1). The ratio of methane generated to the bio-decay of acetic acid concentration was 1:66. The decline of acetic acid in slurry was shown to be a concentration-dependent process. Other volatile fatty acids demonstrated similar declining concentration characteristics but at a lesser rate. This was also the case for 4-methyl phenol with a half life of 495 h. However phenol demonstrated different declining concentration and production characteristics with a maximum concentration of 85 mg l(-1) at 175 h. Carbon dioxide was produced at a greater rate than acetic acid was lost from the slurry (a ratio of 1.88:1.0). Ammonia was emitted at a rate of 4.7 g m(-2) d(-1). (C) 1999 Society of Chemical Industry.

Techniques to identify odorous compounds and to determine their emission rates from liquid wastes are described. Odorous compounds, or odorants, were analysed by GC-MS and odour concentration was measured by olfactometry after being emitted from slurry under controlled environmental conditions using a specially designed odour emission chamber. The slurries were obtained from pigs fed commercial and reduced crude protein diets and stored for 6 weeks, the effects of age and sex upon the odours produced in the headspace of the chamber were evaluated. The major odorous compounds were identified as belonging to the sulphide, volatile fatty acid, phenolic and indolic chemical groups. The mean emission rates from 200 litres of stirred slurry samples with a surface area of 1 m(2) using a wind speed of 4 m s(-1) were 1.35 million Odour Units min(-1) for odour and 214, 2.15, 0.21, 0.44, 0.068 and 0.02 mg min(-1) for hydrogen sulphide, ammonia, phenol, 4-methyl phenol, 4-ethyl phenol and indole respectively. Sex and sex/diet interaction effects were demonstrated for emission rates. (C) 1998 SCI.

A speciation scheme was developed for identification of the chemical forms of manganese in tea leaves and tea infusions. The range of manganese in five different groups of tea leaves was found as 1107–2205 μ g g −1 on dry basis. It was noted that 30.0% of Mn was passed into the water that was present in the form of Mn(II), and also 2.5% of Mn was distributed in the total organic bound and was passed into the various solvents.

Between 1990 and 1992, a series of three experiments compared the effects of incorporating or removing straw from a total of five preceding cereal crops on the nutrient concentration, uptake and processing quality of sugarbeet. Incorporated straw increased K concentrations in tops and roots and increased total K uptake by c 40 kg ha-1. Conversely, incorporated straw reduced Na concentrations and reduced total Na uptake by c 10 kg ha-1. Straw incorporation had little effect on root processing quality, because whilst K impurities increased in the straw incorporated treatments, Na impurities were reduced. Generally, any effects of straw disposal method on concentration and uptake of phosphorus, calcium and magnesium were small and of little agronomic or economic significance. In the absence of regular soil analysis it is recommended that when straw has been incorporated that K fertiliser rates for beet are reduced by c 20 kg ha-1. This is less than the allowance made for cereals. Also, contrary to the current cereal recommendation, there was no evidence for reducing P inputs when straw had been incorporated. © 1997 SCI.