Seeds as potential sources of phenolic compounds and minerals for the Indian population

Seeds are major sources of nutrients and bioactive compounds for human beings. In this work, the chemical composition and physicochemical properties of 155 Indian seeds (belonging to 49 families) are reported. Moisture and ash were measured with reference protocols from AOAC; total polyphenols and flavonoids were measured with spectrophotometric methods after extraction with organic solvents, and mineral elements were determined by X-ray fluorescence spectrophotometry. Total phenolic compounds, flavonoids and mineral contents (Al, Ba, Ca, Cl, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, P, Rb, S, Sr, Ti, V and Zn) were found to vary in the ranges 182–5000, 110–4465 and 687–7904 mg/100 g (DW), respectively. Noticeably, polyphenol contents higher than 2750 mg/100 g were observed in 18 seeds. In addition, mineral contents >5000 mg/100 g were detected in the seeds from Cuminum cyminum, Foeniculum vulgare, Commiphora wightii, Parkia javanica, Putranjiva roxburghii, Santalum album and Strychnos potatorum. Botanical and taxonomical variations in the proximate characteristics of the examined seeds are also discussed

Effect of thermal treatment and storage on bioactive compounds, organic acids and antioxidant activity of baobab fruit (Adansonia digitata) pulp from Malawi

Bioactive compounds of baobab (Adansonia digitata) pulp from Malawi were investigated. The effect of thermal treatment and storage on selected quality attributes of the juice was also evaluated. Organic compounds were analysed by HPLC; total phenol content (TPC) and total antioxidant activity (FRAP, ABTS and DPPH) were measured by spectrophotometry. Malawi baobab pulp contains high levels of procyanidin B2 (533 ± 22.6 mg/100 g FW), vitamin C (AA + DHA) (466 ± 2.5 mg/100 g FW), gallic acid (68.5 ± 12.4 mg/100 g FW) and (−)-epicatechin (43.0 ± 3.0 mg/100 g FW) and showed a maximum TPC of 1.89 × 103 ± 1.61 mg GAE/100 g FW. The maximum antioxidant activity was 2.81 × 103 ± 92.8 mg TEAC/100 g FW for FRAP, 1.52 × 103 ± 17.1 mg TEAC/100 g FW for ABTS and 50.9 ± 0.43% DPPH for DPPH. Thermal pasteurisation (72 °C, 15 s) retained vitamin C which further showed extended half-life under refrigeration temperature (6 °C). Procyanidin B2, (−)-epicatechin, TPC and antioxidant activity fluctuated during storage. Antioxidant activity was significantly correlated (p ≤ 0.05) with bioactive compounds and TPC

Acrilamida ¿un riesgo para la salud del consumidor?

La OTRI del Centro Tecnológico Nacional de la Conserva y Alimentación junto con la OTT del Consejo Superior de Investigaciones Científicas, colaboran en el Proyecto AGROCSIC, el cual fue aprobado por el Ministerio de Ciencia y Tecnología y financiado por el Ministerio de Educación y Ciencia. El objetivo principal de esta nueva actuación es estudiar las distintas líneas de trabajo de los Centros del CSIC relacionadas con la alimentación, para transferir sus resultados al sector industrial.La acrilamida ha entrado ha formar parte del grupo de agentes tóxicos formados durante el procesado de alimentos. Es un hecho indiscutible la formación de acrilamida durante el procesado o cocinado de determinados grupos alimenticios y ello supone un peligro en su condición de perjudicar la salud. Sin embargo, el concepto de riesgo hace referencia a la probabilidad y severidad del peligro. Antes de definir una estrategia efectiva y rigurosa de comunicación y gestión de riesgos sobre la presencia generalizada de acrilamida en alimentos procesados térmicamente es preciso superar con éxito una serie de etapas previas, actualmente, en fase de evaluación. Cuestiones tan importantes como la validación de una metodología robusta de análisis, pasando por complejos estudios tanto de biodisponibilidad como epidemiológicos deben ser resueltos en los próximos años. Es por ello que debemos ser cautos y responsables con la información que lancemos a debate público.Peer reviewe

Reactivity of acrylamide with coffee melanoidins in model systems

Coffee and its substitutes have been described as complex matrices for acrylamide (ACR) analysis due to both analytical interferences and ACR instability in the matrix. Melanoidins are multifunctional and biochemically active polymers which are formed in large extent during coffee roasting. Model systems composed of ACR (elimination studies) or glucose-asparagine (ACR formation/elimination studies) with/without melanoidins was heated at 180 °C. Washed sea sand and cellulose microcrystalline were used as matrix. Coffee melanoidins had a direct influence on the fate of ACR under heating, while the effect was not observed at room temperature. In addition, ACR decrease was also related to the reaction time and the initial amount of melanoidins in the media, where clearly a dose-response was observed. In contrast, pH (from 3.5 to 7.0) had no significant effect on ACR reactivity towards melanoidins. It is hypothesized that nucleophilic amino groups of amino acids from the proteinaceous backbone of melanoidins react via the Michael addition reaction with ACR, although the exact mechanism is unknown. Then, melanoidins could modulate the reaction pathways of ACR formation and elimination during coffee roasting and serve as acrylamide-mitigation substance. © 2011 Elsevier Ltd.Peer Reviewe

Optimised procedure to analyse maillard reaction-associated fluorescence in cereal-based products

Fluorescent Maillard compounds measurement provides more specific information on the extent of the Maillard reaction than other unspecific tools to monitor the reaction, and is suitable, as the first approach, to assess the nutritional quality of foods as related to protein damage. This work presents an optimised laboratory procedure for the measurement of total fluorescent intermediate compounds (FIC) associated with Maillard reaction, described and evaluated in a cereal-based product. Total FIC are evaluated using increased pronase E concentrations and different incubation times for the enzymatic hydrolysis, as well as three different sample clean-up steps after the enzymatic digestion. The effects of basic/acid media are considered for the stability of the fluorescent compounds. The standardised procedure is finally applied to breakfast cereals as a model of cereal-based products, analysing the correlation between total FIC production and fibre and protein contents. It is demonstrated that fluorescent compounds are mainly linked to the protein backbone in ready-to-eat breakfast cereals. Fluorescence measurement is presented as an inexpensive, rapid and accurate procedure to study the extent of Maillard reaction in breakfast cereals.Peer Reviewe

Determination of acrylamide in potato chips by a reversed-phase LC-MS method based on a stable isotope dilution assay

Potato-based products represent an important part of the daily intake of food-derived acrylamide, mainly on adolescent population from western countries. A reversed-phase liquid chromatography-mass spectrometry based on a stable isotope dilution assay was used for acrylamide analysis. Aqueous sample extraction, cleaning with Carrez solution and solid phase extraction with methanol was applied. The ratio potato/NaCl solution is critical during extraction where the optimum ratio is 0.125 g/ml NaCl 2 M solution. The use of virgin olive oil, as retaining matrix, during methanol desiccation was critical to achieve high recoveries. The method performance was validated for limit of detection (23.2 μg/kg) and quantitation (91.8 μg/kg), linearity (r > 0.999, 25-1000 μg/kg), recovery (98.8%). The method was applied on commercial potato chips; the intra-day repeatability was set at 3.9% and values were corrected with a labeled internal standard (13C3- acrylamide). No significant differences on the acrylamide content were observed between industrial-scale and local-scale processed potato chips. © 2005 Elsevier Ltd. All rights reserved.Peer Reviewe

A new application of a commercial microtiter plate-based assay for assessing the antimicrobial activity of Maillard reaction products

A new application of a commercial microtiter plate-based assay was developed for the quantitative screening of antimicrobial compounds formed during the thermal treatment of foods. Such compounds called Maillard reaction products (MRP) are widely distributed in the diet of western countries. The reported method is fast, cheap and easy and facilitates the generation of a dose-response curve which allows calculating the antimicrobial activity of most substances at the same time as minimum inhibitory concentration (MIC) or as oxytetracyclin equivalent value (OTEV). The test is accurate and highly reproducible (inter- and intra-day variation of 2.3% and 1.8%, respectively). For the tested samples, the higher antimicrobial activity was found in coffee melanoidins (high molecular weight fraction of MRP) although non-covalently melanoidins-linked compounds showed antimicrobial activity too. In addition, melanoidins from more severely treated samples exerted higher inhibitory bacterial growing activity, such as CTn60 coffee (highest roasting degree) and dark beer. © 2005 Elsevier Ltd. All rights reserved.Peer Reviewe