Search results for "Maillard Reaction"
showing 10 items of 30 documents
High-performance liquid chromatographic determination of furfural compounds in infant formulas
2002
Furfural contents in adapted and follow-up infant formulas were measured by RP-HPLC. The evolution of furfural compound contents during storage (a year at 20 and 37 °C) was studied. 2-Furylmethylketone and 5-methyl-2-furaldehyde were not detectable in analysed samples. The differences in the furfural compounds at point zero between both infant formulas has to be ascribed to the differences in protein and iron contents. An increase in free 5-hydroxymethyl-2-furfuraldehyde (HMF), 2-furaldehyde (F) and HMF+F contents was observed in all samples, although the differences were not statistically significant. The storage temperature affected the total HMF content and the storage time affected the …
Effects of thermal processing and storage on available lysine and furfural compounds contents of infant formulas.
2000
The Maillard reaction-related effects that thermal treatments during the manufacturing process and storage (at 20 and 37 degrees C) have on powdered adapted and follow-up milk-based infant formulas were estimated by measuring the available lysine and furfural compounds contents of raw cow milk used in manufacturing, intermediate products and formulas. A fluorimetric method was used to measure the available lysine contents, and free and total furfural compounds were determined by HPLC. Statistically significant losses in available lysine (about 20%) in the infant formulas with respect to raw milk were found. The storage period did not affect the available lysine contents of adapted formulas …
High-performance liquid chromatographic determination of Maillard compounds in store-brand and name-brand ultra-high-temperature-treated cows' milk.
2000
Furosine and furfural products of the Maillard reaction are used as specific indicators of the effect of heating treatments on milk quality. Their contents were measured in representative samples of store- and name-brand ultra-high-temperature-treated milks using RP-HPLC with UV detection. Furosine contents ranged from 40.32 to 50.67 and from 65.48 to 310.58 mg/100 g protein in name- and store-brand milks, respectively. Of the furfurals, only hydroxymethylfurfural was detected. The free hydroxymethylfurfural contents of store-brand milks ranged from 0.22 to 1.70 mg/100 g protein. Total hydroxymethylfurfural contents ranged from 0.29 to 0.41 and from 0.72 to 2.21 mg/100 g protein, for name- …
Inactivation and structural changes of polyphenol oxidase in quince ( Cydonia oblonga Miller) juice subjected to ultrasonic treatment
2020
Background Polyphenol oxidase (PPO) is considered a problem in the food industry because it starts browning reactions during fruit and vegetable processing. Ultrasonic treatment is a technology used to inactivate the enzyme; however, the mechanism behind PPO inactivation is still unclear. For this reason, the inactivation, aggregation, and structural changes in PPO from quince juice subjected to ultrasonic treatments were investigated. Different intensities and times of ultrasonic treatment were used. Changes in the activity, aggregation, conformation, and structure of PPO were investigated through different structural analyses. Results Compared to untreated juice, the PPO activity in treat…
Modeling of the process of moisture loss during the storage of dried apricots
2011
[EN] Moisture content is a reference parameter for dried food because the growth of most microorganisms is inhibited below certain water activity levels. In addition, it has a determining influence on the evolution of important parameters, such as color and flavor, and on other properties and deterioration reactions, such as texture, oxidation processes and nutritional value. During the storage of some dried fruits, moisture is produced due to Maillard reactions and exchanged with the surrounding environment through the packaging. The evolution of dried foods during their shelf life depends on the storage conditions. The aim of this study is to analyze the evolution of the moisture content …
Study and characterization of polyphenol oxidase from eggplant (Solanum melongena L.)
2011
ABSTRACT: In this study the catecholase and cresolase activities of eggplant polyphenol oxidase (PPO) were investigated. Enzyme activity was determined by measuring the increase in absorbance using catechol as substrate and 3-methyl-2- benzothiazolinone hydrazone (MBTH) as coupled reagent. The effects of substrate specificity, heat inactivation, temperature, pH, and inhibitors were investigated to understand the enzymatic alteration of ready-to-eat preparations. Browning of vegetables was determined through a colorimeter. Decrease of lightness (L*) and increase of color difference values (ΔE*) were correlated with tissue browning. Antibrowning agents were tested on PPO under the same condit…
Effect of a novel physical pretreatment process on the drying kinetics of seedless grapes
2000
In this paper an alternative physical method for enhancing the drying rate of seedless grapes is proposed. It consists of the superficial abrasion of the grape peel using an inert abrasive material. The effectiveness of this novel process was compared to that of the traditional ethyl oleate dipping process by analysing not only their respective drying times, but also the peel surfaces by scanning electron microscopy. Moreover, the drying kinetics of the above two treatments was reconstructed by using a mathematical model in which the grape pretreatment used was assumed to affect the water diffusivity in the grape peel, but not in the grape pulp. Even though the abrasion method was found to …
Chemical messages in 170-year-old champagne bottles from the Baltic Sea: Revealing tastes from the past
2015
International audience; Archaeochemistry as the application of the most recent analytical techniques to ancient samples now provides an unprecedented understanding of human culture throughout history. In this paper, we report on a multiplatform analytical investigation of 170-y-old champagne bottles found in a shipwreck at the bottom of the Baltic Sea, which provides insight into winemaking practices used at the time. Organic spectroscopy-based nontargeted metabolomics and metallomics give access to the detailed composition of these wines, revealing, for instance, unexpected chemical characteristics in terms of small ion, sugar, and acid contents as well as markers of barrel aging and Maill…
Foodomics assessed by Fourier transform mass spectrometry
2019
Abstract With its ultrahigh resolution power and excellent mass accuracy, Fourier transform ion cyclotron resonance mass spectrometry is the perfct tool to analyze the “foodome” as the set of all polar small molecular compounds present in an investigated food sample. We present here selected applications of this technique in unraveling the metabolome in complex foods (thermally affected, fermentation products, distillates) such exemplified with Maillard reaction products or with wines and spirits. Technical considerations for high resolution mass analyzers are provided from a practical point of view. Moreover, aspects of food safety and nutritional quality are covered by presenting applicat…
Design of Gelatin Pouches for the Preservation of Flaxseed Oil during Storage
2020
Flaxseed oil (FO) is composed mainly of polyunsaturated fatty acids that are very sensitive to oxidation induced by oxygen, temperature, and light. To overcome this problem, gelatin-based films containing glucose are crosslinked via the Maillard reaction (MR) at 120 °