Alcohol-insoluble Substance Research Articles

Impact of microfluidization on the microstructure and functional properties of pea hull fibre

The goal of the present work was to evaluate the impact of the particle size (D90) of microfluidized pea hull fibre suspensions on the physical microstructure, composition and functional properties (i.e. water retention capacity and rheological behaviour). To that end, fibre suspensions with D90 of 120, 100, 80 and 60 μm were produced. Among them, the suspensions of 100 and 80 μm were produced employing two different processing conditions to evaluate the impact of processing on the microstructure and functionality. Suspensions with smaller particles (D90 ≤ 80 μm) presented a thermal stable, pseudoplastic, thixotropic and viscoelastic behaviour varying their elastic modulus in the linear viscoelastic region from 19 to 89 Pa for suspensions with D90 of 80 and 60 μm. By decreasing the D90, it was observed a continuous defibrillation of aggregates of cellulosic macrofibrils, into macrofibrils and microfibrils. Consequently, the number of particles and their interactions by electrostatic and friction forces increased. Alcohol insoluble substances, released from the hemicellulosic and pectic networks, were only detected for the suspensions with D90 = 60 μm. In this case, particles presented inter-fibrillar voids that may increase their flexibility and functionality. For a given particle size distribution, the processing conditions had negligible effect on the functionality. In summary, functionality of microfluidized fibre suspensions may be tuned by controlling the release of alcohol insoluble substances and the defibrillation of the cellulosic network, process conditions then can follow energetic or economic criteria.

Influence of mechanical and thermal treatment on particle structure, leaching of alcohol insoluble substances and water binding properties of pectin-rich orange fibre

Mechanical and thermal processings may affect the composition and the techno-functional properties of dietary fibre as a part of a complex food system. The aim of this study was to investigate the impact of a mechanical and thermal treatment alone or in combination on alcohol insoluble substance (AIS), the content of galacturonic acid (GalA), the water retention capacity (WRC) and the microstructure by scanning electron microscopy (SEM). Two samples of orange fibre with different particle size (coarse and fine) were investigated in an experimental design and evaluated with regard to particle size (d50) after treatment and their impact on network formation. Our study highlights a more pronounced susceptibility of the coarse fibre towards mechanical stress compared to the fine fibre with regard to particle size reduction. High-pressure homogenization (HPH) represents the crucial step regarding AIS release and the increase of WRC for both fibres. A mechanical treatment with additional thermal treatment maximises AIS release. GalA, as a marker for pectin in AIS, was detected in various amounts depending on the intensity of the treatment. Highest values for WRC were achieved for the coarse fibre as a consequence of both, particle size reduction and the formation of a stable network on a microstructural level.

Use of Highly Methoxyl-esterified Cross-linked Alcohol Insoluble Substance to Remove Pectinesterase for the Reduction of Methanol in Sweet Orange Wine

Use of Highly Methoxyl-esterified Cross-linked Alcohol Insoluble Substance to Remove Pectinesterase for the Reduction of Methanol in Sweet Orange Wine

Effects of Pectic Polysaccharides Isolated from Leek on the Production of Reactive Oxygen and Nitrogen Species by Phagocytes

The current survey investigates the effect of four polysaccharides isolated from fresh leek or alcohol insoluble substances (AIS) of leek on the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) from phagocytes. The ability of the polysaccharides to activate serum complement was also investigated. Despite the lack of antioxidant activity, the pectic polysaccharides significantly decreased the production of ROS by human neutrophils. Polysaccharides isolated from AIS markedly activated RAW 264.7 macrophages for RNS production in a concentration-dependent manner. The Western blot analysis revealed that this effect was due to the stimulation of the inducible nitric oxide synthase protein expression of macrophages. The polysaccharides extracted from AIS with water showed the ability to fix serum complement, especially through the alternative pathway. It was found that the polysaccharide that has the highest complement-fixing effect is characterized by the highest content of uronic acids and the highest molecular weight.

Quality Characteristics and Content of Polysaccharides in Green Tea Fermented by Monascus pilosus

In this study, we designed a method to manufacture elevated fermented green tea by using Monascus pilosus, which is known as a functional microbe, and observe its antioxidant abilities and quality characteristics. The water-soluble substance (WSS) content of the fermented tea by M. pilosus (FTM) was lower than that of the non-fermented tea (NFT), although the alcohol-insoluble substance (AIS) content of the FTM was higher than that of NTM. On the other hand, the fractionated distilled water-soluble polysaccharide (DWSP), CDTA-soluble polysaccharides (CDSP), sodium carbonate-soluble polysaccharide (SCSP) and KOH soluble hemicellulose (HC) obtained from the AIS of the FTM was markedly higher than that of NFT. In the antioxidant parameters, the electron donating ability of all fractions, except HC, extracted from FTM was higher than that of NFT, and iron chelating ability of all fractions, except CDSP, extracted from FTM was higher than that of NFT. Whereas the DWSP and SCSP obtained from the FTM were higher than that of NFT, the activity of the HC fraction from both NFT and the FTM could not be detected. In addition, the xanthin oxidase (XO) inhibitory activities of the DWSP, CDSP and the SCSP obtained from the NFT were significantly higher than that of FTM, the aldehyde oxidase (AO) inhibitory activities of the DWSP and SCSP extracted from the FTM were markedly higher than that of the NFT. Meanwhile, the acceptance of NFT and FTM had no significant difference, while the quality of aroma, taste and mouthfeel of the FTM was higher than that of NFT. These results suggest that the post-fermented tea by Monascus microorgan-isms may be responsible for functional components as well as contribute to the improvement of the tea quality.

High‐temperature conditioning induces chilling tolerance in mandarin fruit: a cell wall approach

High-temperature conditioning (3 days at 37 °C and 95% relative humidity), which protects 'Fortune' mandarins from chilling injury (CI), manifested as pitting in the outer part of the peel (flavedo), was applied prior to cold storage (2 °C) in order to investigate the involvement of cell wall composition in the chilling tolerance of mandarins. Both low-temperature storage and high-temperature conditioning barely modified the alcohol-insoluble substance (AIS) content or the degree of pectin esterification in the flavedo. Water-soluble pectins (WSP) were higher in heat-conditioned than in non-conditioned fruits at the onset of CI. In addition, the heat-conditioning treatment was able to increase chelator-soluble pectins (CSP) after short cold storage periods. Covalently bound polyuronides in alkali-soluble pectins (ASP) increased only in fruits with high incidence of CI. Cellulose and hemicellulose increased at 2 °C in both conditioned and non-conditioned fruits, indicating that these polysaccharides may be altered by low temperature but are not related to chilling-induced damage. High-temperature conditioning may reduce chilling-induced flavedo pitting in 'Fortune' mandarin fruit by maintaining normal levels of WSP and increasing putative sites for calcium bridge formation within the cell wall, but not by inducing changes in other matrix cell wall components.

CURE APPEARANCE DEVELOPMENT IN PASTEURIZED CUCUMBER PICKLE MESOCARP TISSUE ASSOCIATED WITH PROTEOLYSIS

Cure appearance development (CAD) of sliced fresh-pack cucumber pickles causes loss of appearance of freshness, which limits market-life. Objectives of this study were to determine differences in hydration characteristics of alcohol-insoluble substances (AIS) and proteins between noncured and cured mesocarp tissues from sliced pasteurized pickles, and the effects of protease on CAD. CAD began close to the placenta and proceeded toward sliced tissues, which were the last to lose white appearance. The rate and total amount of water absorption by AIS from cured mesocarp were substantially greater than that from mesocarp without CAD. CAD increased protein solubility and reduced the protein size indicating involvement of proteolysis. Treatment of fresh mesocarp tissues by pepsin simulated CAD, AIS hydration characteristics and protein degradation that occurred in pasteurized fresh-pack pickles during storage. PRACTICAL APPLICATIONS Because protein degradation appears to be closely associated with cure appearance development (CAD), methods to retard proteolysis should prolong the market-life of sliced fresh pickle products based on the quality of appearance. Currently, sliced fresh-pack products are manufactured throughout the year in order to provide an appearance of freshness, which requires procurement from distant production areas. Methods that hinder CAD would provide the opportunity to extend storage of pickle products manufactured from local production areas.

Thermal Treatment of Eggplant (Solanum melongena L.) Increases the Antioxidant Content and the Inhibitory Effect on Human Neutrophil Burst

The aim of this study was to compare the amount and activity of phytonutrients in raw, grilled, and boiled eggplant fruit using chemical measures and a biological assay of oxidative bursts in human neutrophils. The thermally treated samples showed various changes in their chemical composition (dry matter, soluble solids, acidity, and the amount of alcohol insoluble substances) due to the cooking processes and were much richer in the main phenolic compounds such as chlorogenic and caffeic acids, which are known to be antioxidants. Consequently, their free radical scavenging activity was significantly higher, especially that of superoxide anion. The biological assay of oxidative bursts from human neutrophils in the presence of N-formyl-methionyl-leucyl-phenylalanine confirmed the greater activity of extracts of the cooked eggplants with respect to raw eggplants. Successive extract dilutions showed a significant activity up to 1.25 microg/mL after cooking, while raw fruits resulted in an activity up to 10.00 microg/mL. These results showed that the thermal treatment commonly used before consumption can increase the content and biological activity of antioxidant compounds of eggplants.

Polyuronide content and correlation to optical properties measured by time-resolved reflectance spectroscopy in ‘Jonagored’ apples stored in normal and controlled atmosphere

Abstract Time-resolved reflectance spectroscopy (TRS) studies on fruit have shown that the absorption coefficient (μa) at 670 nm is a good maturity index and that the scattering coefficient ( μ s ′ ) at 780 nm allows an insight into the textural properties of apples. This work aimed at studying the relationship between the polyuronide pattern, firmness and TRS optical properties (μa and μ s ′ ) at 630, 670, 750 and 780 nm measured in ‘Jonagored’ apples at harvest, after 6 months’ storage in normal (NA) and controlled atmosphere (CA), and after 7 days of post-storage shelf life at 20 °C. Results showed that fruit of different TRS maturity class had a different polyuronide content, even if their firmness was not different: ‘less mature’ (high μa630) fruit compared to ‘more mature’ (low μa630) ones showed at harvest higher total galacturonic acid (GA) content, residue insoluble pectin (RIP) and protopectin index (PI), and lower GA content in oxalate-soluble pectin (OSP) fraction, indicating a less advanced breakdown of insoluble protopectins to soluble pectins. The μa630 and μa670 were correlated to alcohol-insoluble substances (AIS) and GA content in RIP measured after storage: as maturity increased, GA decreased in RIP, showing pectin solubilisation. AIS, water-soluble pectin (WSP), RIP and PI measured after storage were highly correlated to scattering coefficients measured after storage. Generally, with increasing μ s ′ , AIS and GA in WSP increased while firmness, RIP and PI decreased. CA apples were characterised by lower μ s ′ values than NA ones, along with lower WSP and OSP and higher total GA, RIP and PI.

Yield and Quality of Pectins Extractable from the Peels of Thai Mango Cultivars Depending on Fruit Ripeness

Pectins, recovered from the peels of four mango ( Mangifera indica L.) cultivars by mimicking industrial techniques, were evaluated in terms of yield, composition, macromolecular properties, and technofunctional quality. Freeze-dried peels of mature-green fruits, after major mesocarp softening, and at full ripeness were extracted using hot acid. The pectins were precipitated in propan-2-ol and their crude yields quantified as alcohol-insoluble substance. Like apple pomace, the dried peels provided hardly acetylated (DAc < 6.3%) rapid-set to ultrarapid-set high-methoxyl pectins at starch-adjusted yields of 11-21 g/100 g. However, despite similar high molecular weight fractions and galacturonic acid/rhamnose ratios, their average molecular weight was markedly reduced by a characteristic, almost monodisperse fraction of 16000-19000. Expanded galactans, indicated by galactose/rhamnose ratios of 15-24 mol/mol, probably represented arabinogalactan side-chain fragments withstanding hot-acid extraction at pH 1.5 and 2.0, as implied by arabinose/galactose ratios of 8-15 and 33-56 mol/100 mol, respectively. Limited galacturonic acid contents made the mango peel pectins less valuable than commercial apple pectins with regard to gelling capacity and thickening properties. Whereas starch and matrix glycan fragments almost completely degraded during ripening, depolymerization of pectins and galactans was insignificant. Technofunctional properties, modulated by extraction at different pH values, were ascribed to structural differences influencing macromolecular entanglements.

Interactions between dietary fibre-rich preparations and glycoconjugated bile acids in vitro

Binding in small intestine and excretion of bile acids constitute a major hypocholesterolemic pathway. Interactions between different types of commercial and laboratory-made dietary fibres and glycoconjugated bile acids were investigated in vitro at pH 5.0 and 6.5. The interactions were greater at the lower pH and with dihydroxy-bile acids. Digested cereal products (barley, oat, rye and wheat flour; oat bran), alcohol-insoluble substances from apples, strawberries, rowan berries, carrots, white cabbage, red beets and sugar beet pulp, as well as arabinoxylan, bound 1.21–1.77 μmol bile acids/100 mg of preparation at pH 5.0. Novelose bound approximately 0.65 μmol bile acids/100 mg. Carob fibre had the highest binding capacity (1.83–1.96 μmol bile acids/100 mg) whereas cellulose had no effect. Besides the source and chemical composition, the bile acid binding correlated especially well with the presence of three-dimensional cell wall structures of the tested preparations but less well with the proportions of soluble and insoluble dietary fibre.

Chitosan-Ascorbate 함유 동해심해수로 담근 물김치의 품질특성

우리나라 동해심해수의 효율적 활용을 위한 방안의 하나로 chitosan-ascorbate(CA) 0.1%를 함유하는 동해심해수로 담근 물김치의 품질특성을 조사하였다. 물김치제조는 담금 용수로 mineral salt 1% 함유 증류수(DW), 염도 1% 동해심 해수(ED), DW＋CA(DW-CA) 및 ED＋CA(ED-CA)로 구분하여 10℃에서 12일간 숙성시켰다. 그 결과, ED-CA는 물김치 숙성시 pH의 감소와 산도의 증가를 상당히 지연시키며, 총균수를 감소시키면서 젖산균비율을 높여 위생성을 증진시키며, 항산화성을 높이는 효과가 있었다. 또한 탁도를 감소시켜 국물을 맑고 투명하게 유지하며, 김치조직의 연화 현상을 막아 경도유지와 조직의 알코올 불용성 물질의 용출을 지연시키며, 종합적 기호도를 증진시키는 효과를 나타내어 물김치 담금용수로서의 활용이 기대된다.

Dietary fiber–rich colloids from apple pomace extraction juices do not affect food intake and blood serum lipid levels, but enhance fecal excretion of steroids in rats

The aim of this study was to investigate the effects of colloids isolated from apple pomace extraction juices (so-called B-juices) produced by enzymatic liquefaction on food intake, levels of blood serum lipids, and fecal excretion of bile acids (BA) and neutral sterols (NS) in vivo. Ten male Wistar rats per group were fed diets containing either no apple dietary fiber (DF) (control), a 5% supplementation with juice colloids, or an alcohol-insoluble substance (AIS) from apples for 6 weeks. Apple DF in diets led to lower weight gain in rats fed with B-juice colloids ( P< 0.05). For these rats, food intake was not affected but was highest with feeding AIS (10% more than control) to cover energy requirements. The supplementation of diet with apple DF from extraction juices or AIS had minor effects on blood serum lipids. In rats fed either juice colloids or AIS, up to 30% (5.31 μmol/g dry weight) and 88% (7.69 μmol/g dry weight) more primary BA were excreted in feces, respectively, as compared to that in the control group (4.10 μmol/g dry weight) ( P < 0.05). In cecal contents, a 15% (juice colloids) to 37% (AIS) increase in primary BA was found. In contrast, concentrations of secondary BA were lower in feces of test groups ( P < 0.05). Excretion of total BA and NS was higher in rats fed apple DF ( P < 0.05). Our study is the first to prove that there are beneficial physiologic effects of apple DF isolated from pomace extraction juices produced by enzymatic liquefaction. These results may help to develop such innovative juice products that are rich in DF of fruit origin for diminishing the lack of DF intake.

Effects of dietary fibre-rich juice colloids from apple pomace extraction juices on intestinal fermentation products and microbiota in rats.

Effects of colloids isolated from apple pomace extraction juices (so-called B-juices) produced by enzymic liquefaction on food intake, body and faecal weights, short-chain fatty acid (SCFA) profile and selected intestinal microbiota were investigated in rats. Ten male Wistar rats per group were fed diets without any apple dietary fibre (DF) (control) or supplement with 5 % B-juice colloids or an alcohol-insoluble substance (AIS) from apples for 6 weeks. Rats fed with apple DF (5 % B-juice colloids or AIS) gained less weight than control rats (P<0.05). B-juice colloids did not affect food intake, whereas feeding AIS resulted in a 10 % higher food consumption than in control rats. Both juice colloids and AIS increased the weight of caecal contents in rats and lowered luminal pH values (P<0.05). In addition, SCFA concentrations and total yields were also raised (P<0.05) in caecum of these rats indicating good fermentability of apple substrates by gut microflora. Distinctly higher concentrations of acetate and propionate were found in intestinal contents of juice colloid-fed rats (P<0.05), whereas AIS also increased butyrate yield. Changes in microbiota due to apple DF in diets were restricted in the caecum to the Eubacterium rectale cluster (AIS; P<0.05) and in faeces to the Bacteroidaceae (juice colloids and AIS; P<0.05). The present study shows the physiological effects of apple DF isolated from pomace extraction juices produced by enzymic liquefaction on intestinal fermentation. Results may be helpful for the development of such innovative juice products that are rich in DF of fruit origin.

Calcium Lactate Treatment after Salting of Chinese Cabbage Improves Firmness and Shelf-life of Kimchi

In order to enhance the firmness and shelf-life of kimchi, as well as to increase the content of well-absorbed digestible calcium, the effect of calcium lactate (CaL) treatment of salted Chinese cabbage on pH, titratable acidity, total microbes, lactic acid bacteria, alcohol insoluble substance (AIS) content, firmness, mineral content and tissue structure were investigated. Treatment with the Cal solution increased pH and decreased titratable acidity, which was more pronounced at higher concentrations. The edible period evaluated by pH was 7～8 days for non-treated kimchi, 10 days for 1% treated kimchi, 15 days for 2% treated kimchi and 20 days for 3% treated kimchi. Total microbes were reduced, but lactic acid bacteria counts were higher in the treated group. CaL treated kimchi showed higher AIS content and firmer texture, which was more conspicuous in the 2 and 3% CaL treated groups. Calcium content in kimchi fermented for 15 days was 40.75～41.53 mg%, which is 42～45% higher than that in the control group. The sodium content was 23～54% less in the treated groups. The epidermis and vascular bundle tissue of kimchi fermented for 15 day was damaged more severely in the control group than in the treated group. CaL treated kimchi has a crispier taste and the development of sour taste was delayed. Therefore, addition of CaL can produces a kimchi with high calcium as well as superior texture and shelf-life, when adjusting the concentration according to the fermentation periods.

Degradation of apple cell wall material by commercial enzyme preparations.

The action of commercial enzyme preparations on the release of cell wall constituents from alcohol-insoluble substance prepared from apples without skins and cores as well as their influence on the water binding of remaining residues is described as a model for the enzymatic cell wall destruction during production of liquid fruit products. Besides 'normal' enzyme concentrations adapted from the usual industrial dosage, 'tenfold' enzyme concentrations were applied. Dependent on enzyme spectrum and activities, concentrations of dietary fibre, e.g., pectin, increased in the soluble fractions using conditions of enzymatic 'mash treatment'. A further release of these cell wall constituents occurred when cellulase containing enzyme preparations were used under conditions of 'pomace treatment', especially with the 'tenfold' enzyme dosage. The partial enzymatic degradation of the cell wall material is connected with a decrease in water binding of the remaining residues during both simulated mash treatment of pomace treatment. Alcohol-insoluble substance from apples is a suitable model for the determination of complex enzymatic actions of enzyme preparations containing pectolytic, hemicellulolytic, and/or cellulolytic activities under standardised conditions.

Enzymatic degradation studies of pectin and cellulose from red beets.

The influence of structural features of the cell wall polysaccharides pectin and cellulose on the enzymatic degradation of red beet was evaluated. Alcohol-insoluble substances and acetone-insoluble residues were prepared from red beets and characterized with respect to the content of dietary fibre, pectin fractions, neutral saccharide composition and water absorption. The high-methylated and high-acetylated pectin component was partly soluble in water and in EDTA. Pectin was hardly extractable from alcohol-insoluble substances as well as from red beets. Isolated pectin could not be completely degraded by pectolytic enzymes. After de-acetylation, the pectic acid from red beets was degradable in a similar rate like citrus pectic acid. From alcohol-insoluble substances, several cellulose and lignin fractions were prepared and analysed. A cellulose preparation from red beets was intensely degraded by cellulases with high activities as shown by the release of reducing end-groups, viscosity and scanning electron microscopy. Cell wall preparations from red beets were able to bind high amounts of water. A decrease in water absorption during enzymatic action or changes in viscosity and flow behaviour are sensitive markers for decomposition or depolymerization processes. Furthermore, an inhibitor of microbial enzymes was isolated from red beets and acetone-insoluble residues. The main reason for the poor enzymatic liquefaction or maceration of red beets by pectolytic and cellulolytic enzymes is the high degree of acetylation of the pectin component.

Effects of commercial pectolytic and cellulolytic enzyme preparations on the apple cell wall.

The action of three different commercial enzyme combinations on apple cell wall material has been examined in a model system under conditions of mash and pomace treatment by using an alcohol-insoluble substance prepared from apples. A part of the total dietary fiber, for example, galacturonan (pectin), appeared in the soluble fraction after enzymatic mash treatment. The soluble fraction increased intensely during pomace treatment. Furthermore, enzyme actions caused a change in the water-binding capacity of residues as well as changes in the monosaccharide composition and in the molecular weight distribution of saccharides in filtrates (soluble parts). The extent of decomposition of cell wall material and the increase of soluble oligomeric and/or polymeric dietary fiber components are caused by both the composition (pectinases, cellulases, and hemicellulases) and the activities of the enzyme preparations. The model experiments allow an insight into the reactions occurring during enzyme action on the plant cell wall, for example, during apple juice production using pectolytic and cellulolytic enzyme preparations.

Material properties of processed fruit and vegetables

Using apple mash prepared from apple parenchyma, the effect of the processing steps of cold and warm water treatment, respectively, on structure and material properties of treated mashes, as well as dried and rehydrated materials with cellular structure (MCS), compared to alcohol-insoluble substance (AIS), were investigated. Cold water treatment gives rise to pectin-enriched, relatively large and mechanically stable cell clusters which show good elastic and solid-state properties in aqueous dispersions. However, warm water treatment effects a thermal hydrolytic degradation of pectin in the MCS whereby the mechanical cell separation is simplified and reduced structural stability of the dispersions can be observed. AIS contains the biggest particles and best material properties in comparison to MCS. The connection between structural parameters which are affected by processing and material properties, in addition to the importance of AIS and MCS, respectively, as model substrates, are discussed.

Rheological examination of material with cellular structure

Properties of rehydrated materials with cellular structure can be investigated by making creep and oscillation measurements. Such rehydrated material and alcohol-insoluble substances can be classified rheologically as concentrated suspensions with viscoelastic properties. As well as its concentration, the material properties of the disperse phase are important determinants of the rheological properties of disperse systems. In our creep measurement experiments under defined conditions dominant reversible elastic parts are obtained at high concentrations ≥90%. Frequency sweep measurements within the linear-viscoelastic region at γ = 0.001 leads to the assumption that all rehydrated samples are dispersions. This is due to the fact that storage and loss moduli are almost independent of the measuring frequency. The alcohol-insoluble substance forms the most stable dispersion, followed by the basic material. In contrast, the homogenized material had dominant viscous properties. The results are specific for each material and depend on the frequency and concentration. Data derived from rheological measurements allow a complex characterization of materials with cellular structure through mathematical models (linear relationships).