Effects of Heat Treatment and Dehydration on Pineapple (Ananas comosus L. Merr) Cell Walls

Author(s):  
Antoni Femenia ◽  
Susana Simal ◽  
Carme Garau Taberner ◽  
Carmen Rosselló

The effects of thermal processing on the physico-chemical properties of cell walls from pineapple flesh tissues have been investigated. Commercially canned pineapple exhibited a similar cell wall composition to the fresh pineapple sample, although a marked increase in cell wall solubility, from 21 to 34%, was detected. Dehydration promoted important changes in cell wall components and related functional properties, in particular when relatively high air-drying temperatures were applied. Thus, samples dried at 60ºC and, in particular at 80ºC, exhibited a larger solubilisation/degradation of pectic polysaccharides, probably due to either ?-elimination processes or enzyme-catalyzed degradation. On a fresh weight basis, about 14% and up to 39% of cell wall pectins were not recovered for the dried pineapple at 60ºC and 80ºC, respectively. Pectins from the latter samples also exhibited a notable decrease in the degree of esterification. These physico-chemical changes were probably reflected on the decrease of functional properties such as swelling (Sw), water retention capacity (WRC) and fat adsorption capacity (FAC). Nevertheless, fresh, canned and dehydrated pineapple at 40ºC exhibited higher WRC and FAC values, about 30 g water/g AIR and 15 g oil/g AIR, respectively. A gradual decrease of Sw, WRC and FAC values was observed for the functional properties of pineapple samples dried at 60 and 80ºC. Moreover, high air-drying temperatures also promoted a significant decrease in cell wall solubility. Therefore, the influence that these effects might have on the nutritional properties of cell walls or dietary fibre of thermally processed fruits such as canned and/or dehydrated pineapple needs to be considered.

Author(s):  
Cai-Hong Wang ◽  
Yi-Long Ma ◽  
Dan-Ye Zhu ◽  
Hao Wang ◽  
Ya-Fei Ren ◽  
...  

Dietary fiber are non-digestible constituents of plant cell walls, and comprise a necessary component of diet and its positive connection with human health. Till now, there is no report about the extraction and physicochemical and functional properties of dietary fiber from bamboo shoots. To find the potential applications of dietary fiber from bamboo shoots in food and health products, the effects of chemical, enzymatic methods and particle size distribution on the chemical and structural composition, physicochemical, and functional properties of dietary fibers (DFs) from bamboo shoots were studied. The results showed that BSEDF and BSCDF had higher total DF and higher soluble DF, respectively. The crystalline regions calculated to be higher in latter and both had irregular surfaces and diverse monosaccharide composition. Both fibers showed good functional properties [water retention capacity (WRC) (11.24-15.13g/g), water swelling capacity (WSC) (18.84-28.75 mL/g), oil holding capacity (OAC) (6.71-10.15 g/g), glucose adsorption capacity (GAC) (0.08-6.89 mmol/g) and glucose retardation index (GRI) (3.57-40.92%)]. WRC of BSCDF and BSEDF decreased with the increase in the mesh size (40-200) while, WSC and OAC increased with mesh sizes (40 to 120), followed by decrease above mesh120. Both particle size and extraction methods significantly affected GRI. In conclusion, physico-chemical properties of fibers can be manipulated through treatments (chemical and enzymatic) to improve their overall functionality. Therefore, both BSCDF and BSEDF can find potential applications in food and health products as a functional ingredient in different aspects.


2019 ◽  
Vol 32 (1) ◽  
pp. 1-8
Author(s):  
N. Sharma ◽  
T. Sinderpal

Physico-chemical properties are crucial characteristics of hydrocolloids as they decide the applicability of them. Rheology of system, flow behaviour and mechanical properties make hydrocolloids suitable for food industry. Modification of consistency or texture properties of functional polymers also controls their sensory characteristics, thereby they become significant essences such as thickener, gelling agents, foaming agent, texture modifier, viscosifier, emulsifier, stabilizer and binder. Industrial and pharmaceutical applications are also controlled by some suitable physico-chemical properties of hydrocolloids. The polysaccharide gum exudates constitute a architecturally distinct class of complex biomacromolecules having unique physico-chemical properties. Due to their good bio/tissue compatibility, non-toxicity, they are extensively used in the field of tissue engineering, drug delivery and wound healing. Chemical and molecular architecture of hydrocolloids in turn controls their physico-chemical and functional properties. Sterculia gum is a substituted rhamnogalacturonoglycan (pectic) type exudate gum used as suspending agent, gelling agents, emulsifier, bulk laxative, dental adhesive, drug delivery agent and wound healing agent. It exhibits high water retention capacity, high viscosity and least solubility. Solutions of sterculia gum are viscoelastic and thixotropic. Sterculia gum has been recommended as effective wound dressing material as it can form a intensely adhesive gel when dispersed in minimum ammount of water. Owing to wide applications and distinctive properties of sterculia gum, present work is an endeavor to summarize the molecular organization, chemical configuration and physico-chemical properties of sterculia gum and the factors affecting physico-chemical properties of sterculia gum.


Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1017
Author(s):  
Ana Teresa Noguerol ◽  
Marta Igual ◽  
M. Jesús Pagán-Moreno

The aim of this research was to evaluate the nutritional and physico-chemical properties of six different vegetable fibers and explore the possibility of using them as a thickener or gelling agent in food. To determine the technological, nutritional and physical parameters, the following analyses were carried out: water-holding capacity, water retention capacity, swelling, fat absorption capacity, solubility, particle size, moisture, hygroscopicity, pH, water activity, bulk density, porosity, antioxidant activity, phenolic compounds and mineral content. Gels were prepared at concentrations from 4% to 7% at 5 °C and analyzed at 25 °C before and after treatment at 65 °C for 20 min. A back extrusion test, texture profile analysis and rheology were performed and the pH value, water content and color were analyzed. As a result, all the samples generally showed significant differences in all the tested parameters. Hydration properties were different in all the tested samples, but the high values found for chia flour and citrus fiber are highlighted in functional terms. Moreover, chia flour was a source of minerals with high Fe, Mn and Cu contents. In gels, significant differences were found in the textural and rheological properties among the samples, and also due to the heat treatment used (65 °C, 20 min). As a result, chia flour, citrus, potato and pea fibers showed more appropriate characteristics for thickening. Moreover, potato fiber at high concentrations and both combinations of fibers (pea, cane sugar and bamboo fiber and bamboo, psyllium and citric fiber) were more suitable for gelling agents to be used in food products.


2009 ◽  
Vol 69 (3) ◽  
pp. 969-977 ◽  
Author(s):  
AFU. Carvalho ◽  
MCC. Portela ◽  
MB. Sousa ◽  
FS. Martins ◽  
FC. Rocha ◽  
...  

This work aims to assess the potential of the green seaweed Ulva fasciata Delile as an alternative source of dietary fibre (DF). Total DF content was determined, some of its physico-chemical properties described and the physiological effects of U. fasciata meal on rats fed a hypercholesterolemic diet were investigated. U. fasciata may be considered a potential alternative source of DF with a total content of about 400 g.kg-1 (dry basis) and interesting physico-chemical properties: water retention capacity of 8.74 g/water.g-1 dry sample (seaweed meal) and 0.90 (seaweed carbohydrate extract), lipid adsorption capacity of 4.52 g/oil.g-1 dry sample (seaweed meal) and 5.70 (seaweed carbohydrate extract), intrinsic viscosity of 2.4 dl.g-1 (seaweed carbohydrate extract) and cation exchange capacity of 3.51 Eq.kg-1 (seaweed carbohydrate extract). The diet containing seaweed meal was able to keep rats' total cholesterol (TC) down without causing any undesirable increase in LDL-C fraction. No evidence of toxic and/or antinutritional components in the seaweed meal was detected. Rats showed a fecal volume much greater (13 g) than that fed on cellulose diet ( 7 g) (p < 0.05). These properties confer on the seaweed the potential to be used in food technology for the acquisition of low-calorie food and might be important in body weight control, reduction of blood TC and LDL-C as well as in prevention of gastrointestinal diseases.


Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1510
Author(s):  
María Ángeles Rivas ◽  
Rocío Casquete ◽  
María de Guía Córdoba ◽  
Santiago Ruíz-Moyano ◽  
María José Benito ◽  
...  

The objective of this study was to evaluate, from a technological and nutritional point of view, the chemical composition and functional properties of the industrial winemaking by-products, namely skins, stems and lees. The chemical and physical characteristics, as well as the functional properties (fat and water retention and swelling capacity, antioxidant capacity, and their prebiotic effect), of the dietary fibre of these by-products were studied. The results showed that the skins, stems, and lees are rich in fibre, with the stem fibre containing the highest amounts of non-extractable polyphenols attached to polysaccharides with high antioxidant activity and prebiotic effect. Lee fibre had the highest water retention capacity and oil retention capacity. The results reveal that winemaking by-products could be used as a source of dietary fibre with functional characteristics for food applications.


2018 ◽  
Vol 61 (3) ◽  
pp. 1165-1174 ◽  
Author(s):  
Manjot Singh ◽  
Akinbode Adedeji ◽  
Dipak Santra

Abstract. Evaluation of the postharvest properties of nine proso millet cultivars was carried out to determine their physical and engineering properties, which are very useful for designing appropriate systems for process operations such as sorting, drying, heating, cooling, and milling. Nine cultivars of proso millet comprising waxy and non-waxy types, namely Cope, Earlybird, Huntsman, Minco, Plateau, Sunrise, Rise, Dawn, and Panhandle, were obtained from the Panhandle Research and Extension Center, University of Nebraska, Scottsbluff. Results showed significant (p &lt; 0.05) differences in their physical properties, such as sphericity, volume, bulk density, porosity, and angle of repose, which ranged from 0.86 to 0.91, from 3.94 to 5.14 mm3, from 765.49 to 809.67 kg m-3, from 42.49% to 44.20%, and from 22.98° to 25.74°, respectively. The cultivars were also evaluated for their pasting and gelatinization properties, and high correlation was found between amylose content and onset temperature (r = -0.94), peak gelatinization temperature (r = -0.92), peak viscosity (r = 0.84), final viscosity (r = 0.91), and setback viscosity (r = 0.90). The understanding of these basic physical and functional properties of proso millet cultivars will form the foundation for processing them into value-added products. Keywords: Chemical properties, Pasting properties, Proso millet.


2018 ◽  
Vol 10 ◽  
pp. 7-10
Author(s):  
Anubodh Karki ◽  
Pravin Ojha

Standardized milk having casein: fat ratio 0.92 was used and the processes were optimized for the manufacture of cheeses. The samples were analyzed for physico-chemical properties (moisture, total solid, fat, protein, ash, calcium, fat retention, protein retention, yield) and functional properties such as meltability, stretchability, baking quality and shreddability were also analyzed. Significant differences (p<0.05) were found in calcium content of the cheese, color and overall sensory properties. Stretchability and shreddability in relation to functional properties were also found to be significantly different. The yield for mozzarella cheese made using rennet was higher than that of cheese made using kiwi juice as milk coagulant and also it was superior in terms of overall functional properties. It was deemed that a good quality mozzarella cheese with variant characteristics can be prepared by using kiwi juice as milk coagulant.


1990 ◽  
Vol 269 (2) ◽  
pp. 393-402 ◽  
Author(s):  
P Ryden ◽  
R R Selvendran

1. Polymers were solubilized from the cell walls of parenchyma from mature runner-bean pods with minimum degradation by successive extractions with cyclohexane-trans-1,2-diamine-NNN′N′-tetra-acetate (CDTA), Na2CO3 and KOH to leave the alpha-cellulose residue, which contained cross-linked pectic polysaccharides and Hyp-rich glycoproteins. These were solubilized with chlorite/acetic acid and cellulase. The polymers were fractionated by anion-exchange chromatography, and fractions were subjected to methylation analysis. 2. The pectic polysaccharides differed in their ease of extraction, and a small proportion were highly cross-linked. The bulk of the pectic polysaccharides solubilized by CDTA and Na2CO3 were less branched than those solubilized by KOH. There was good evidence that most of the pectic polysaccharides were not degraded during extraction. 3. The protein-containing fractions included Hyp-rich and Hyp-poor glycoproteins associated with easily extractable pectic polysaccharides, Hyp-rich glycoproteins solubilized with 4M-KOH+borate, the bulk of which were not associated with pectic polysaccharides, and highly cross-linked Hyp-rich glycoproteins. 4. Isodityrosine was not detected, suggesting that it does not have a (major) cross-linking role in these walls. Instead, it is suggested that phenolics, presumably linked to C-5 of 3,5-linked Araf residues of Hyp-rich glycoproteins, serve to cross-link some of the polymers. 5. There were two main types of xyloglucan, with different degrees of branching. The bulk of the less branched xyloglucans were solubilized by more-concentrated alkali. The anomeric configurations of the sugars in one of the highly branched xyloglucans were determined by 13C-n.m.r. spectroscopy. 6. The structural features of the cell-wall polymers and complexes are discussed in relation to the structure of the cell walls of parenchyma tissues.


2016 ◽  
Vol 61 (No. 4) ◽  
pp. 141-149 ◽  
Author(s):  
R.K. Jha ◽  
P.K. Prabhakar ◽  
P.P. Srivastav ◽  
V.V. Rao

Aloe vera possesses therapeutic, antioxidant and some other functional properties. These properties may be affected by processing operations. The present study investigated the influence of operating temperature on vacuum drying characteristics, functional properties and the inner solid structure of the fresh aloe vera gel. The gel was dried at a constant pressure of 720 mm Hg in the drying chamber at varying temperature of 30&ndash;60&deg;C. The experimental data of moisture ratio of Aloe vera were used to fit different models and the effective moisture diffusion coefficients and activation energy were also calculated. The Page model was found to be the best fit to experimental data. The functional properties like water retention capacity, fat absorption capacity, and swelling of the dried product were studied and found to be decreased with increasing operating temperature. The damage to the inner solid structure was more pronounced at higher temperatures because of faster mass transfer through the pores of the solid. The best quality product was obtained when the temperature was maintained at 30&deg;C.


2001 ◽  
Vol 54 (1) ◽  
pp. 74-83 ◽  
Author(s):  
VINOD R. HEGDE ◽  
JACK SILVER ◽  
MAHESH PATEL ◽  
VINCENT P. GULLO ◽  
RAYMOND YARBOROUGH ◽  
...  

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