Effects of Processing on the Compositions and Physicochemical Properties of Fibre Concentrate from Cooked Fruit Pomaces

in Food and Bioprocess Technology (in press)

This study examined the influence of applied tech- nologies namely desugaring, grinding, and bleaching on the compositions (cellulose, hemicelluloses, lignins, and pectins), physicochemical properties ... [more ▼]

This study examined the influence of applied tech- nologies namely desugaring, grinding, and bleaching on the compositions (cellulose, hemicelluloses, lignins, and pectins), physicochemical properties (water-holding capacity (WHC), swelling capacity (SWC), oil-holding capacity (OHC)) and the colour of dietary fibre (DF) during the production of fibre concentrates from unusual cooked apple and pear pomaces. Thermogravimetric analysis (TGA) and optical microscopy were also performed to monitor process-induced modifica- tion. All the processing conditions affected the compositions and physicochemical properties of DF. The bleaching treat- ment induced the greatest changes on DF producing yellow cellulose-rich fibre concentrates with improved WHC from 3.2 to 10.0 g/g and improved SWC from 4.0 to 8.8 ml/g. Otherwise, reduction of the particle size influenced hydration properties and colours of DF. WHC and SWC tended to increase with the particle size whereas smaller granulometric size increased the lightness of fibres. Desugaring increased the DF content in both pomaces by 1.2-fold with slight modifica- tion of apple insoluble dietary fibre ratio. Fibre concentrates had improved WHC and SWC up to 1.4-fold. All processes had no significant effect (p < 0.05) on OHC of DF except with ultrafine apple fibre concentrates. Results showed that pro- cessing had overall positive effects on DF contents and hy- dration properties of pomaces from cooked fruits. Bleached fibre concentrates from apple pomace had the highest WHC (10.0 g/g) whereas that of pear had the highest fibre content (89.9 %). Fibres from cooked fruit pomaces may therefore be used as textural ingredients or functional foods. [less ▲]

Fast and high yield recovery of arabinose from destarched wheat bran

in Industrial Crops & Products (2013), 43

Enzymatically destarched wheat bran (DWB) contained 13.8% of arabinose and 23.1% xylose. Up to a maximum of 70% of the arabinose was progressively released from DWB when heated at 80 or 100°C in media ... [more ▼]

Enzymatically destarched wheat bran (DWB) contained 13.8% of arabinose and 23.1% xylose. Up to a maximum of 70% of the arabinose was progressively released from DWB when heated at 80 or 100°C in media acidified with HCl. Whereas microwave irradiation at higher temperatures in pressure vessels could lead to higher yields of extraction. A Box-Behnken experimental design established an efficient model describing the effects of temperature, irradiation duration and pH on arabinose extraction. The pH appeared as the most important factor of the process. 4-5 min of microwave heating at 150ºC and pH 1 appeared as a fast and highly efficient method to recover more than 90% of the arabinose of DWB. When plotting the percentages of arabinose against the combined severity factors LogR’0 (calculated from the temperature/duration/pH conditions applied), two different fitting profiles were obtained for both the heating techniques. Under microwave heating, high free xylose’s release could also occur. The experimental design led to a quadratic model predicting the release of xylose from DWB. A range of conditions enabled to minimize xylose and hydrolyze around 50% of the total arabinose, yielding a high purity fraction. An alternative would be to release more than 90% of both arabinose and xylose, for further arabinose purification or for a common valorization of both pentoses. [less ▲]

Characterization of by-products from cooked fruit processing and potential use in food products

in Journal of Food Composition and Analysis (2012), 27

The process that produces Lie`ge syrup (apple butter-like) results in high amounts of residues from cooked apples, pears and sun-dried dates. These unusual fruit by-products were studied for their ... [more ▼]

The process that produces Lie`ge syrup (apple butter-like) results in high amounts of residues from cooked apples, pears and sun-dried dates. These unusual fruit by-products were studied for their composition in total proteins and fats, dietary fiber (DF) and their content in total and free monosaccharides. All three by-products contained around 20% of total non-cellulosic monosaccharides and around 10% of free monosaccharides. According to two different methods, DF accounted for 70% of the dry weight (DW) with an insignificant soluble fraction; pectin represented 2–3% of DW. Apple and pear residues were composed mainly of cellulose, whereas lignin was the main fraction for dried date. The polyphenolic content and the antioxidant activity of the three products were also assessed and the values showed that their antioxidant characteristics were comparable to that of various raw fruits. No phenolic acids were detected, indicating that the cooking process resulted in their extraction. The lyophilized and ground residues exhibited high water holding capacities (between 5.2 g water per g DW for pear and 8.6 for apple) and average oil holding capacities (around 2.5 g oil per g DW), whereas their color was light brownish as shown by the L*, a*, b* coordinates determined. These data open the possibility to contemplate new specific and niche applications for such by-products. Besides, it provides information about the effects of a cooking process on apple and pear pomaces, as well as on an unusual residue from a dried fruit (date). [less ▲]

Enzymatic production of pectic oligosaccharides from polygalacturonic acid with commercial pectinase preparations

in Food and Bioproducts Processing: Transactions of the Institution of Chemical Engineers, Part C (2011), 90(3), 588-596

The present study investigates the individual efficiency of six commercial pectinase preparations (Endopolygalacturonase M2, Pectinase, Viscozyme L, Pectinex Ultra SP-L, Pectinase 62L and Macer8 FJ) in ... [more ▼]

The present study investigates the individual efficiency of six commercial pectinase preparations (Endopolygalacturonase M2, Pectinase, Viscozyme L, Pectinex Ultra SP-L, Pectinase 62L and Macer8 FJ) in catalyzing the liberation of pectic oligosaccharides (POS) from polygalacturonic acid. On the basis of high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) analysis of the enzymatic hydrolysates, products release kinetics revealed a random cleavage pattern and an exo mode of cleavage for all the enzymes except for Endopolygalacturonase M2. All six enzymes generated oligoGalA with different degree of polymerization (DP); the quantitative composition of oligoGalA depended on the enzyme specificity and the time of enzymatic reaction. Endopolygalacturonase M2 was the best enzyme preparation for production of oligoGalA, with 18% (wt) of digalacturonic acid and 58% (wt) of trigalacturonic acid after 2h of reaction. Concerning galacturonic acid production, Pectinase 62L was superior to the other enzyme preparations with 47% (wt) after 1h of reaction. [less ▲]

Extraction And Characterization Of Water-Extractable And Water-Unextractable Arabinoxylans From Spelt Bran: Study Of The Hydrolysis Conditions For Monosaccharides Analysis.

in Journal of Cereal Science (2011)

Peroxisomal β-oxidation and Production of γ-decalactone by the Yeast Rhodotorula aurantiaca

in Notulae Botanicae Horti Agrobotanici Cluj-Napoca (2010), 2

The utilization of gum tragacanth to improve the growth of Rhodotorula aurantiaca and the production of γ-decalactone in large scale

in Applied Biochemistry and Biotechnology (2009)

The production of γ-decalactone and 4-hydroxydecanoic acid by the psychrophilic yeast R. aurantiaca was studied. The effect of both compounds on the growth of R. aurantiaca was also investigated and our ... [more ▼]

The production of γ-decalactone and 4-hydroxydecanoic acid by the psychrophilic yeast R. aurantiaca was studied. The effect of both compounds on the growth of R. aurantiaca was also investigated and our results show that γ-decalactone must be one of the limiting factors for its production. The addition of gum tragacanth to the medium at concentrations of 3 and 4 g/l seems to be an adequate strategy to enhance γ-decalactone production and to reduce its toxicity towards the cell. The production of γ-decalactone and 4- hydroxydecanoic acid was significantly higher in 20-l bioreactor than in 100-l bioreactor. By using 20 g/l of castor oil, 6.5 and 4.5 g/l of γ-decalactone were extracted after acidification at pH 2.0 and distillation at 100 °C for 45 min in 20- and 100-l bioreactors, respectively. We propose a process at industrial scale using a psychrophilic yeast to produce naturally γ-decalactone from castor oil which acts also as a detoxifying agent; moreover the process was improved by adding a natural gum. [less ▲]

Production of γ-Decalactone by a Psychrophilic and a Mesophilic Strain of the Yeast

in Applied Biochemistry and Biotechnology (2009)

Among 18 psychrophilic strains isolated near the Antarctic Station, the psychrophilic strain Rhodotorula aurantiaca A19 was selected for its ability of growth and γ- decalactone production at low ... [more ▼]

Among 18 psychrophilic strains isolated near the Antarctic Station, the psychrophilic strain Rhodotorula aurantiaca A19 was selected for its ability of growth and γ- decalactone production at low temperatures. The effects of temperature, initial pH, and castor oil concentration on the growth and γ-decalactone production by a psychrophilic and a mesophilic strain of R. aurantiaca were investigated. The highest γ-decalactone production in flasks (5.8 g/l) was obtained with the strain A19 at 14 °C and initial pH 7.0 in medium containing 20 g/l castor oil. On the other hand, these factors did not affect the production of γ-decalactone by the mesophilic strain. In fermentor, a γ-decalactone concentration of 6.6 g/l was reached with the strain A19, whereas a maximum of 0.1 g/l was obtained with the mesophilic strain. Our results suggest that the ability to synthesize γ-decalactone is a particularity of the strain A19, since the mesophilic strain (no. 30645) produced small amounts, and the other (no. 31354) did not exhibit this property. It is, to our knowledge, the first report of γ-decalactone production by R. aurantiaca and furthermore by a psychrophilic yeast strain. Moreover, the amount of γ-decalactone obtained in fermentor with the strain 19 was on the order of concentrations usually described in patents. [less ▲]

Production and toxicity of γ-decalactone and 4-hydroxydecanoic acid from Rhodotorula aurantiaca

Poster (2009)

The objective of this study was to compare the production of γ- decalactone in different scales and to study the effects of 4- hydroxydecanoic acid and γ-decalactone on the growth of R. aurantiaca. The ... [more ▼]

The objective of this study was to compare the production of γ- decalactone in different scales and to study the effects of 4- hydroxydecanoic acid and γ-decalactone on the growth of R. aurantiaca. The effect of gum tragacanth on the production of γ-decalactone by R. aurantiaca was evaluated. [less ▲]

Interesterification of rapeseed oil with anhydrous milk fat and its stearin fraction

Poster (2009)

The compositional changes occurring during the lipase-catalysed interesterification of AMF/rapeseed oil (RO) and AMF stearin fraction (AMFSF)/RO blends were described in the first part of this study. In ... [more ▼]

The compositional changes occurring during the lipase-catalysed interesterification of AMF/rapeseed oil (RO) and AMF stearin fraction (AMFSF)/RO blends were described in the first part of this study. In the present and second part are reported the resulting changes in physical properties, especially the melting behaviour through solid fat content (SFC), dropping point (DP) and fusion profiles by differential scanning calorimetry (DSC). [less ▲]