Extractability and evaluation of α-galactosides of sucrose in leguminous seeds

The levels of sucrose and α-galactosides of sucrose in a range of leguminous seeds extracted by various procedures and analysed by the gel-permeation technique are reported. Cowpeas contained the highest levels of α-galactosides, dry weight basis, the lowest levels being recorded in chickpeas. Levels in lupins are almost comparable with soybeans and intermediate quantities have been measured in adzuki beans. All the legumes examined contained varying amounts of α-galactoside-hydrolysing enzyme (α-galactosidase EC 3.2.1.22) and the defatting process has no effect on its activity. No hydrolysis of these oligomers due to the extraction technique has been observed, except in one procedure. Conditions of cultivation may have been responsible for anomalies in the values of these oligomers observed by various investigators within the same variety and species of a leguminous seed.     

The role of processing and matrix design in development and control of microstructures in dairy food production—a survey

New options to process dairy products by means of new single unit operations or combinations thereof are presented. The innovative possibilities discussed in this paper mainly refer to novel ways of influencing product microstructures or textures as perceived during consumption, by means of contributions of single molecule fractions of complex systems derived from membrane fractionation techniques. In addition, options to integrate physiologically active components which also have a structure forming effect in fermented or other dairy products are highlighted. Alternatives derived from thermal, mechanical and enzymatic processing and from fractionation techniques by means of membranes are presented which can be exploited for fractionation and compositional matrix design of dairy products.     

Extracts of edible and medicinal plants in inhibition of growth, adherence, and cytotoxin production of Campylobacter jejuni and Campylobacter coli

Abstract: Campylobacter spp. is recognized as one of the most common cause of food‐borne bacterial gastroenteritis in humans. Campylobacter infection causes campylobacteriosis, which can range from asymptomatic to dysentery‐type illnesses with severe complications, such as Guillian‐Barre syndrome. Epidemiological studies have revealed that consumption of poultry products is an important risk factor of this disease. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces have been proposed to be critical steps in pathogenesis. Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. In this study, 28 edible or medicinal plants species were analyzed for their bactericidal effects on the growth of Campylobacter jejuni and C. coli. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus‐indica, and Cynara scolymus were the most effective against these microorganisms at minimal bactericidal concentrations (MBCs) of 0.3, 0.5, 0.4, and 2.0 mg/mL, respectively. No effect on growth was detected with lower concentrations of extract (25%, 50%, or 75% of the MBC) added to the media. The effect of each extract (75% of the MBC) on adherence and cytotoxicity of C. jejuni and C. coli was evaluated in Vero cells. Adherence of Campylobacter to Vero cells was significantly affected by all the extracts. Cytotoxic activity of bacterial cultures was inhibited by A. farnesiana and A. ludoviciana. These plant extracts are potential candidates to be studied for controlling Campylobacter contamination in foods and the diseases associated with this microorganism. Practical Application: Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus‐indica, and Cynara scolymus were the most effective against these microorganisms. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces which are critical steps in pathogenesis were decreased by these extracts. Our results point to these plants as potential candidates for the control of Campylobacter contamination in foods, the treatment of the diseases associated with this microorganism, and as feed supplements to reduce on‐farm prevalence of Campylobacter.     

Uptake of α-tocopherol in porcine plasma and tissues

The effect of feeding α-tocopheryl acetate to pigs on the rate and extent of uptake of α-tocopherol in various tissues was investigated. The rate of iron ascorbate-induced lipid peroxidation was also studied. One hundred and eight Landrace × Large White pigs were assigned at random to one of the following barley-based diets: 20 mg α-tocopheryl acetate/kg feed for up to 126 days; 20 mg/kg feed to day 91, followed by 200 mg/kg feed to day 126, or 200 mg/kg feed for up to 126 days: Pigs from each group were slaughtered at specified intervals. For pigs fed the diet supplemented with 200 mg α-tocopheryl acetate/kg feed, α-tocopherol levels increased with increasing supplementation time up to day 126 in all tissues studied. The highest levels of α-tocopherol were observed in kidney fat and subcutaneous fat (inner layer) followed by subcutaneous fat (outer layer), liver, lung, heart, kidney, with muscle and brain containing approximately the same level. The α-tocopherol concentrations in all tissues examined, from pigs fed 200 mg α-tocopheryl acetate/kg feed from weaning to day 126 were greater than those fed the supplemented diet for 35 days. Iron-induced lipid peroxidation was reduced by dietary α-tocopheryl acetate supplementation, and muscle samples from pigs supplemented for 126 days were significantly (p < 0.05) less susceptible to peroxidation compared to muscle from pigs fed the same supplemented diet for 35 days.     

Rapid determination of α-tocopherol in muscle and adipose tissues of pork

A fast, sensitive and reproducible method for the analysis of -tocopherol in pork tissues is presented. It combines saponification of the tissue and -tocopherol extraction in a single vessel, followed by HPLC separation and fluorescence detection. Added -tocopherol was recovered quantitatively. The reduction of lipid peroxides with potassium iodide before the saponification step did not alter the amounts of -tocopherol detected. Membranebound -tocopherol was not oxidized by lipid peroxides during the procedure. The coefficient of variation of -tocopherol analysed using this method was ±4.2% for muscle and ±2.5% for adipose tissues.

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Methode zur schnellen Bestimmung von -Tocopherol in Muskel- und Fettgeweben des Schweines

Zusammenfassung Es wird eine schnelle, empfindliche und reproduzierbare Methode zur Bestimmung von -Tocopherol im Schweinefleisch vorgestellt. Die Methode verbindet die Verseifung des Gewebes und die Extraktion in einem Gefäß. Nach HPLC-Abtrennung wird das -Tocopherol mit einem Fluoreszenzdetektor bestimmt. Zugesetztes -Tocopherol wurde quantitativ wiedergefunden. Die Reduktion der Lipidperoxide mit Kaliumjodid vor der Verseifung hatte keinen Einfluß auf die im Gewebe bestimmten -Tocopherolgehalte. Das membrangebundene -Tocopherol wird während der Bestimmung nicht durch Lipidperoxide oxidiert. Der Variationskoeffizient der Methode lag für Muskelgewebe bei ±4,2% und für Fettgewebe bei ±2,5%.

     

Analysis of preference and satisfaction of cashmere products in China北大核心

This survey was data from the national economic research team with industry technology system of sheep industry of 16 city, 11 counties of countrywide consumer in 2013 February. Through the analysis of cashmere products in China consumer preferences and satisfaction of cashmere products, we can understand the actual situation of our country's cashmere products consumption, and promote the development of cashmere products consumption. The results show that; the majority of consumer preference pure cashmere, cashmere products more than half of the consumers buy the cashmere content of more than seventy percent; the majority of consumers to accept the cashmere sweater for the price of 2000 yuan, 2000 yuan more than the consumer of the cashmere sweater acceptable proportion is very small; In addition, consumers pay more attention to comfort, price, warmth retention property of cashmere sweater.     

Occurrence of deoxynivalenol and its 3-β-D-glucoside in wheat and maize

Deoxynivalenol-3-β-D-glucoside (D3G), a phase II plant metabolite of the mycotoxin deoxynivalenol (DON), occurs in naturally Fusarium-contaminated cereals. In order to investigate the frequency of occurrence as well as the relative and absolute concentrations of D3G in naturally infected cereals, 23 wheat samples originating from fields in Austria, Germany and Slovakia as well as 54 maize samples from Austrian fields were analysed for DON and D3G by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Both analytes were detected in all the 77 field samples. DON was found at levels from 42 to 4130 ng g^?1 (977 ± 1000 ng g^?1 on average). The D3G concentrations in all cereal samples were in the range 10–1070 ng g^?1 (216 ± 253 ng g^?1 on average), corresponding to about 5–46 mol% of their DON concentrations (15 ± 8 mol% on average).     

Effects of nutritional level on pork quality and gene expression of μ-calpain and calpastatin in muscle of finishing pigs

The study was designed to investigate the effects of nutritional level (control diet (CD), 14.19% crude protein, 13.81 MJ of DE/kg; low nutritional level diet (LND), 11.08% crude protein, 12.55 MJ of DE/kg) on pork quality and gene expression of μ-calpain and calpastatin in muscle of finishing pigs. The LND treatment increased drip loss (P < 0.05), had a trend to increase intramuscular fat (IMF) content (P = 0.09), decreased Warner–Bratzler shear force (WBSF) of pork (P < 0.05), improved mRNA level of μ-calpain (P < 0.05) in skeletal muscle, but had no effect on gene expression of calpastatin, compared with the CD treatment. These data suggest that a moderately reduced energy and protein diet increased pork tenderness and intramuscular fat. The increase in tenderness by LND treatment may be partly due to increased gene expression of μ-calpain in muscle.     

Investigation of the composite system of β-lactoglobulin and pectin in aqueous solutions

The compatibility in aqueous systems of β-lactoglobulin (β-lg) with low and high esterified-sodium polypectates (LMP and HMP) was investigated. The mixture did not separate into two co-existing liquid phases in any case studied. At pH above the isoelectric point (IP) of β-lg, the behavior of LMP and HMP was similar when mixing with β-lg. Pectins and β-lg were co-soluble was around a particular ionic strength (μ) (0.07 M for HMP and 0.3 M for LMP). In these circumstances, the flow behavior of pectin was hardly affected by the addition of β-1g . At all other μ, the mixture formed a liquid phase containing both β-lg and pectin and a small amount of β-lg precipitates. Here, the viscosity of the liquid phase was slightly higher than the viscosity of a solution containing the same concentration of pectin. At pH 3.5, i.e. pH⩽IP of β-lg, the behavior of LMP and HMP was different when mixing with β-lg. LMP formed insoluble complexes with β-lg at low μ (⩽0.25 M), but precipitation was suppressed at high μ (0.5 M). The composite system of β-lg/HMP formed a white, homogeneous and stable dispersion at low μ (0.07 M). The viscosity of this dispersion was much higher than the additive viscosity of individual solutions would be. Probably, the oppositely charged β-lg and HMP formed soluble complexes, which further associated into large aggregates. This complexation was also suppressed at high μ (0.5 M).     

Aflatoxin M1 in processed milk and infant formulae and corresponding exposure of adult population in Serbia in 2013–2014

Aflatoxin M₁ (AFM1) occurrence was analysed in 80 samples of milk and 21 samples of infant formulae on the Serbian market, using high-performance liquid chromatography with fluorescence detection. All milk samples collected in 2013 showed AFM1 contamination in the range 0.02–0.32 μg kg^?1, with a mean level of 0.13 μg kg^?1. The EU maximum level for AFM1 in milk (0.05 μg kg^?1) was exceeded in 75% of the samples. In 2014, AFM1 was found in 83%, 70%, 80% and 58% of the samples collected in April, July, September and December, respectively, exceeding the limit in 5% of the samples taken in July. The additional number of liver cancer cases per year associated with exposure to AFM1 was estimated to be 0.004 in the adult population. Regarding infant formulae, AFM1 was found in only one sample.     

A survey of β-glucan and arabinoxylan content in wheat

BACKGROUND: Dietary fibre lowers the risk of coronary heart disease and colorectal cancer. This survey quantifies mixed link β‐glucan (MBG) and arabinoxylan (AX) in wheat and investigates relationships between the grain carbohydrates. MBG and AX contents were measured in 500 and 200 wheat accessions respectively, including diploid, tetraploid and hexaploid genotypes comprising primitive, synthetic and elite lines. RESULTS: Overall, MBG contents ranged between 1.8 and 18.0 g kg^?1 grain dry weight. In wheat–barley addition lines and triticale hexaploids the levels were 9.0–11.3 and 3.5–9.6 g kg^?1 respectively. The amounts in synthetic wheats were nearer their tetraploid parents than their diploid parents. AX and total non‐starch polysaccharide (NSP) contents ranged from 23.7 to 107.5 g kg^?1 and from 31.7 to 136.7 g kg^?1 respectively. Linear regressions showed that the relationships of starch and grain weight with NSP glucose were stronger than those with AX. CONCLUSION: The results indicated insufficient genetic diversity in the germplasm surveyed to initiate a breeding programme to increase the amount of MBG in wheat grain to 20 g kg^?1, a level considered high enough to confer a 10–15% reduction in blood cholesterol. Copyright © 2011 Society of Chemical Industry     

Expression and characterization of β-1,3-1,4-glucanase of Aspergillus usamii in Escherichia coli and its application in sourdough bread making

A β-1,3-1,4-glucanase gene (Auglu12A) from Aspergillus usamii was successfully expressed in Escherichia coli BL21(DE3). The recombinant enzyme, reAuglu12A was efficiently purified using the one-step nickel-nitrilotriacetic acid affinity chromatography. The specific activity of reAuglu12A was 694.8 U/mg, with an optimal temperature of 55°C and pH of 5.0. The reAuglu12A exhibited stability at temperatures up to 60°C and within the pH range of 4.0–5.5. The reAuglu12A hydrolytic activity was increased in the presence of metal ions, especially K⁺ and Na⁺, whereas it exhibited a K_m and V_max of 8.35 mg/mL and 1254.02 µmol/min/mg, respectively, toward barley β-glucan at pH 5.0 and 55°C. The addition of reAuglu12A significantly increased the specific volume (p < 0.05) and reduced crumb firmness and chewiness (p < 0.05) of wheat–barley sourdough bread during a 7-day storage period compared to the control. Overall, the quality of wheat–barley sourdough bread was improved after incorporation of reAuglu12A (especially at 3000 U/300 g). These changes were attributed to the synergistic effect of acidification by sourdough and its metabolites which provided a conducive environment for the optimal action of reAuglu12A in the degradation of β-glucans of barley flour in sourdough. This stabilized the dough structure, thereby enhancing the quality, texture, and shelf life of the bread. These findings suggest that reAuglu12A holds promise as a candidate for β-glucanase application in the baking industry.     

Comparison of estrone and 17β-estradiol levels in commercial goat and cow milk

Increased levels of estrogen metabolites are believed to be associated with cancers of the reproductive system. One potential dietary source of these metabolites that is commonly consumed worldwide is milk. In North America, dairy cows are the most common source of milk; however, goats are the primary source of milk worldwide. In this study, the absolute concentrations of unconjugated and total (unconjugated plus conjugated) estrone (E(1)) and 17β-estradiol (E(2)) were compared in a variety of commercial cow milks (regular and organic) and goat milk. A lower combined concentration of E(1) and E(2) was found in goat milk than in any of the cow milk products tested. The differences in E(1) and E(2) levels between regular and organic cow milks were not as significant as the differences between goat milk and any of the cow milk products. Goat milk represents a better dietary choice for individuals concerned with limiting their estrogen intake.     

Cluster formation and phase separation in mixtures of sodium κ-carrageenan and sodium caseinate

Mixtures of the polysaccharide κ-carrageenan (KC) and caseinate proteins (SC) from milk were investigated at pH 7 in aqueous solution using confocal scanning laser microscopy and light scattering. Phase separation was observed at higher concentrations and the phase diagram was established. In the mixtures SC was observed to form large aggregates mediated by a relatively small amount of KC. At small KC concentrations the aggregates were initially relatively small and could be characterized by light scattering. At higher KC concentrations or on longer storage at 20 °C, dense clusters with a radius of a few microns were formed that slowly precipitated. The fraction of precipitated protein increased linearly with increasing KC concentration, but was independent of the protein concentration. It increased with decreasing pH from about 20% at pH 8 to 100% at pH 5.     

Role of β-conglycinin and glycinin subunits in the pH-shifting-induced structural and physicochemical changes of soy protein isolate

Soy β-conglycinin (7S) and glycinin (11S) were incubated up to 4 h in acidic (pH 1.5 to 3.5) or alkaline (pH 10 to 12) solutions to induce protein structural unfolding followed by refolding 1 h at pH 7.0, a process known as pH-shifting. The pH-shifting markedly increased (P < 0.05) emulsifying activity of 11S and to a lesser extent 7S; the former also produced more uniform oil droplets. The emulsifying activity improvements were accompanied by a significant rise in protein surface hydrophobicity, slight loss of the secondary structure (circular dichroism), and substantial dissociation of disulfide-linked basic and acidic 11S subunits. The findings suggested that 11S globulins of soy protein isolate (SPI) were more responsive to pH-shifting treatments than were 7S globulins, and the resulting emulsifying activity enhancements of 11S, in parallel with that of SPI, were indicative of its determinant role in the overall emulsifying properties of pH-shifting-treated SPI. PRACTICAL APPLICATION: Extreme alkaline (pH 12) and acidic (pH 1.5) medium treatments can significantly modify the structure and enhance the emulsifying properties of both β-conglycinin and glycinin components of SPI. The functionality improvement by the pH processes is more remarkable for the glycinin protein fraction. Therefore, SPI enriched with glycinin seems to be particularly suitable for extreme acidic or alkaline processes to produce surface-active functional ingredients for food applications.     

Interaction of phosphatidylcholine and α-tocopherol on the oxidation of sunflower oil and content changes of phosphatidylcholine and tocopherol in the emulsion under singlet oxygen

Abstract: Interaction of phosphatidylcholine (PC) and α‐tocopherol (α‐Toc) on the oxidation of oil in the emulsion consisting of sunflower oil and water under singlet oxygen at 25 °C was studied by determining peroxide value (PV) and conjugated dienoic acid (CDA) contents. Singlet oxygen was produced by chlorophyll b under 1700 lux. Single addition of PC or α‐Toc decreased the values of peroxides and CDAs of oil in the emulsion via singlet oxygen quenching. PC and α‐Toc showed simply additive interaction in decreasing the singlet oxygen oxidation of oil in the emulsion. α‐Toc was a physical quencher of singlet oxygen in the emulsion, but PC involved chemical quenching in the antioxidant action. Chlorophyll and PC contents were decreased in the emulsion under singlet oxygen, while α‐Toc was not. α‐Toc protected chlorophyll and PC from degradation, and was a more important component than PC in the oil oxidation under singlet oxygen in the emulsion.     

Degradation of γ- and α-tocopherol and formation of 5-nitro-γ-tocopherol induced by peroxynitrite in liposomes and skeletal muscle

Peroxynitrite, formed from the reaction between nitric oxide and superoxide, can participate in free radical-mediated reactions with cellular components in muscle to (1) initiate lipid oxidation via the production of lipid hydroperoxides, and (2) produce novel nitrated products. 5-Nitro-γ-tocopherol (NGT) is formed by the electrophilic substitution reaction between peroxynitrite and γ-tocopherol. The objective of this research was to examine the utility of NGT as a lipid-phase, peroxynitrite-specific biomarker in muscle foods. NGT was detected when exogenous peroxynitrite was added to liposomes containing γ-tocopherol and homogenates from chicken dark and turkey light muscle with added γ-tocopherol. Detectable levels of NGT were not observed in either minced turkey light muscle stored at -20?°C or chicken dark muscle stored at 4?°C. These results suggest that NGT is not a suitable biomarker to confirm the presence of endogenously produced peroxynitrite in muscle foods.