Nuria Grigelmo-Miguel

Characterisation of low-fat high-dietary fibre frankfurters

Two different peach dietary fibre (DF) suspensions (17 and 29%) were used to obtain low-fat high-DF frankfurters (20-5% fat) which were compared to an all-meat control (25% fat). The viscosity of the meat batters increased with DF content. The protein (11.5±0.6%) and collagen (1.4±0.1%) contents of frankfurters were not affected by DF addition, and the higher the DF content, the lower the pH (6.4 to 5.8) due to the fibre solution acidity. The DF was effective in retaining added water in low-fat frankfurters since their cooking losses were similar to those of the controls (5.5±0.1%). Low-fat frankfurters were darker and browner than the controls and only high fibre addition significantly decreased the textural parameters. Sensory evaluation indicated that low fat-high DF frankfurters (20, 15 and 10% fat) were as acceptable as the all-meat frankfurters.

Characterization of dietary fiber from orange juice extraction

Abstract Residues from orange juice extraction are potentially an excellent source of dietary fiber (DF), because this material is rich in pectin and may be available in large quantities. Chemical and physical characteristics of DF obtained from orange pulp were determined for three varieties of oranges. Total DF content reached quite high values: 35.4–36.9% dry matter (DM). Orange DF was rich in pectins (15.7–16.3% DM), as well as cellulose and hemicellulose (16.6–18.1% DM) and lignin (2.2–3.0% DM). The product showed a relatively high water holding capacity (7.3–10.3 g water/g fiber), high oil absorption property (0.9–1.3 g oil/g fiber) and low caloric value (3519–3735 cal/g). Chemical analyses of orange DF concentrate showed low contents of protein, fat and ash (8.1–10.1%, 1.5–3.0% and 2.6-3.1% DM, respectively). The orange DF color ranged from yellow to light orange. These characteristics suggested many potential applications such as, clouding agent in beverages, thickener and gelling agent as well as binder, texturizer and low calorie bulk ingredient.

Characterisation of peach dietary fibre concentrate as a food ingredient

Abstract Insoluble and soluble dietary fibre (DF) fractions of peach DF concentrate, obtained by an enzymatic-chemical method, were analysed for neutral sugars, uronic acids and Klason lignin. Proximate composition, energy value, colour and water- and oil-holding capacities were also determined. Total DF constituted 31–36% dry matter (DM) of the concentrate and insoluble DF was its major fraction (20–24% DM). The high proportion of soluble fraction (11–12% DM) in the peach DF concentrate, in comparison with cereal brans, was noticeable. Insoluble and total dietary fibre contents significantly decreased throughout the harvest time of the original fresh fruit. Results suggested that peach DF concentrate may be not only an excellent DF source but an ingredient in the food industry because it showed a high affinity for water (9.12–12.09 g water/g fibre) and low energy (3.723–3.494 kcal/g). However, the use of this material could affect the colour and pH of the final product.

Influence of fruit dietary fibre addition on physical and sensorial properties of strawberry jams

Abstract The physical and sensorial properties of strawberry jams using fruit dietary fibre (DF) as a stabiliser were evaluated and compared with those made with a commercial thickener. Strawberry jams of up to 55 °Brix were obtained from the total or partial substitution of commercial amidade pectin by peach DF in a standard formulation. The strawberry jams showed a pseudoplastic behaviour well described by the power-law model and the higher the DF content, the higher the viscosity observed in the jams. The pH value was kept within the ranges 3.08–3.29 with no influence of the DF addition. Sensory evaluation indicated that high fruit DF jams were as acceptable as conventional jams, but high DF strawberry jams were darker than the control ones.

Influence of the Addition of Peach Dietary Fiber in Composition, Physical Properties and Acceptability of Reduced-Fat Muffins

Muffins were made with 2, 3, 4, 5 or 10% peach DF to study the feasibility of developing reduced-fat baked products with peach. DF was substituted for oil in a standard muffin recipe, and the resulting products were compared to control muffins (100% oil). Reduced-fat muffins with peach DF had more moisture, protein and minerals as well as fewer calories than the control. The addition of peach DF darkened the muffins and increased their hardness and chewiness. However, springiness and cohesiveness were not different in muffins with or without DF. On the other hand, there were no differences between the acceptability of reduced-fat muffins with peach DF up to 4% and control muffins.

Rheology of peach dietary fibre suspensions

Abstract The flow behaviour of peach (var. Sudanell) dietary fibre (DF) suspensions was determined with a concentric cylinder viscometer at a temperature range of 15–65°C. The behaviour of peach DF suspensions was pseudoplastic and fitted well to the power-law model. The Arrhenius model described the effect of temperature on the apparent viscosity (ηapp) and the activation energy of flow (Ea) was in the range 5.2–14.3 kJ/mol, depending on the concentration. Changes of ηapp with concentration in pseudoplastic suspensions fitted well to a power-law model at the used temperature range. In all the cases, the effect of concentration on ηapp was more pronounced than the effect of temperature; an exponential expression for the combined effect of temperature and concentration on the ηapp was given.