In Vitro Bioaccessibility of Colored Carotenoids in Tomato Derivatives as Affected by Ripeness Stage and the Addition of Different Types of Oil.

Unlabelled: The simultaneous effect of tomato ripeness stage (mature green, pink, and red-ripe), mechanical processing (dicing and grinding), and oil addition (coconut, sunflower, and olive oils) on the amount and bioaccessible fraction of carotenoids were evaluated. Tomato products obtained from fruits at the most advanced ripeness stage exhibited the greatest values of both concentration and bioaccessible fraction of total carotenoids and lycopene. The type of processing also exerted an important influence on carotenoids content, as well as on its bioaccessibility.

Physical and structural changes in liquid whole egg treated with high-intensity pulsed electric fields.

Unlabelled: Liquid whole egg (LWE) is currently pasteurized through the application of heat; however, this treatment entails deleterious effects against some of the functional and technological properties of the product. In this study, the effect of high-intensity pulsed electric fields (HIPEF) processing (field strength: 19, 32, and 37 kV/cm) was compared to the traditional heat pasteurization (66 °C for 4.5 min).

High-intensity pulsed electric fields processing parameters affecting polyphenoloxidase activity of strawberry juice.

High-intensity pulsed electric fields (HIPEF) were applied to strawberry juice to study the feasibility of inactivating polyphenoloxidase (PPO). Response surface methodology was used to evaluate the effect of HIPEF processing, in which total treatment time (1000 to 2000 μs), pulse frequency (50 to 250 Hz), pulse width (1.0 to 7.

Effects of high-intensity pulsed electric fields on lipoxygenase and hydroperoxide lyase activities in tomato juice.

The influence of high-intensity pulsed electric field (HIPEF) parameters, namely, pulse frequency, pulse width, and polarity on tomato juice lipoxygenase (LOX) and hydroperoxide lyase (HPL) activities was studied using a response surface methodology. Samples were subjected to square-shaped pulses of 35 kV/cm for 1000 micros, with pulse width ranging from 1 to 7 micros at frequencies from 50 to 250 Hz, either in monopolar or bipolar mode. Tomato LOX was more resistant to HIPEF than HPL within the range of assayed conditions.

Control of Pathogenic and Spoilage Microorganisms in Fresh-cut Fruits and Fruit Juices by Traditional and Alternative Natural Antimicrobials.

  Traditional antimicrobials have been extensively used for many years. However, consumers are currently demanding wholesome, fresh-like, and safe foods without addition of chemically synthesized preservatives. The application of novel natural antimicrobials to assure safety of fresh-cut fruits and unpasteurized juices while preventing quality loss is a promising alternative.

Influence of storage temperature on the kinetics of the changes in anthocyanins, vitamin C, and antioxidant capacity in fresh-cut strawberries stored under high-oxygen atmospheres.

Changes in the main antioxidant properties of fresh-cut strawberries stored under high-oxygen atmospheres (80 kPa O(2)) were studied at selected temperatures (5 to 20 degrees C). The suitability of zero- and 1st-order kinetics as well as a model based on Weibull distribution function to describe changes in experimental data is discussed. A non-Arrhenius approach was used to determine the temperature dependence of the estimated rate constants.

Effect of natural antibrowning agents on color and related enzymes in fresh-cut Fuji apples as an alternative to the use of ascorbic acid.

Polyphenoloxidase (PPO) and peroxidase (POD) were evaluated in fresh-cut Fuji apple slices and the effeet of the individual or combined use of ascorbic acid, 4-hexylresorcinol, N-acetylcysteine, and glutathione on their respective activities was determined. Additionally, color changes during storage at 4 degrees C were measured throughout 14 d of storage. PPO activity increased with storage time and was inhibited by the individual use of N-acetylcysteine and glutathione.

Inactivation of Salmonella enterica Ser. Enteritidis in tomato juice by combining of high-intensity pulsed electric fields with natural antimicrobials.

The effect of high-intensity pulsed electric field (HIPEF) treatment (35kV/cm, 4 mus pulse length in bipolar mode without exceeding 38 degrees C) as influenced by treatment time (200, 600, and 1000 micros) and pulse frequency (100, 150, and 200 Hz) for inactivating Salmonella enterica ser. Enteritidis inoculated in tomato juice was evaluated. Similarly, the effect of combining HIPEF treatment with citric acid (0.

Quality changes in fresh-cut Fuji apple as affected by ripeness stage, antibrowning agents, and storage atmosphere.

The effect of ripening state, modified atmosphere, and the use of antibrowning agents was investigated in an attempt to determine optimum ripeness and processing conditions for extending the shelf-life of fresh-cut Fuji apple. Apples were classified in 3 groups: mature-green, partially ripe, and ripe; after peeling and slicing, fruits were treated with 1% (w/v) N-acetylcysteine, or 1% (w/v) ascorbic acid (control), and then packed into polypropylene trays with air or a gas mixture (2.5% O2 + 7% CO2 + 90.

Respiratory rate and quality changes in fresh-cut pears as affected by superatmospheric oxygen.

Changes in the respiration rate of fresh-cut "Flor de Invierno" pears stored under superatmospheric oxygen concentrations were studied and compared to those observed under traditional modified atmosphere packaging conditions. Changes in package headspace O(2) and CO(2) concentrations throughout storage were curve-fitted to nonlinear equations, calculating respiration rates by combining the derivatives of the equations and the gas permeations throughout storage. Moreover, relationships between respiratory activity and quality parameters of fresh-cut Flor de Invierno pears dipped into an antioxidant solution (0.