Reduction of aflatoxin B1 during tortilla production and identification of degradation by-products by direct-injection electrospray mass spectrometry

Abstract

Objective. To determine the effect of pH, and exposure time over the inactivation of aflatoxin B 1 (AFB 1 ) during the tortilla making process as well as the degradative molecules generated. Materials and methods. Inactivation of AFB 1 in maize-dough with alkaline pH and in alkaline methanolic solutions was determined by HPLC. Kinetics of time exposure of AFB 1 in methanolic solution and the degradative products were analyzed by direct injection electrospray mass spectometry (DIESI-MS). Results. The alkaline pH of the maize-dough after nixtamalización between 10.2, and 30-40 minutes of resting at room temperature allows the 100% reduction of AFB 1 . DIESI-MS analysis of the extracts indicated the presence of two degradation molecules from AFB 1 . Conclusion. The alkaline pH of maize-dough and resting time are the principal factors involved in diminishing AFB 1 levels in tortillas. A procedure to the tortilla making process is proposed, which allows the reduction of remnant AFB 1 , avoiding the accumulative effect over consumers. ResumenObjetivo. Determinar el efecto del pH alcalino de la masa de maíz y el tiempo de exposición sobre la aflatoxina B 1 (AFB 1 ) durante la producción de tortillas e identificar los posibles productos de degradación mediante DIESI-MS. Material y métodos. La inactivación de la AFB 1 a pH alcalino y diferentes tiempos de exposición en masa nixtamalizada y en soluciones metanólicas fueron determinadas por HPLC. La cinética de degradación de AFB 1, y los productos de degradación en soluciones metanólicas se determinaron por DIESI-MS. Resultados. El pH alcalino de la masa y 30 a 40 minutos de reposo redujeron en 100% la AFB 1 adicionada. Se identificaron dos moléculas de degradación. Conclusión. Los principales factores involucrados en la disminución de la AFB 1 durante la producción de tortillas son la hidrólisis alcalina y el tiempo de reposo. Se propone un procedimiento para la producción de tortilla que reducirá la AFB 1 residual evitando el efecto acumulativo en los consumidores.

Effect of combination processing on aflatoxin reduction: process optimization by response surface methodology

“…It was evident that the pH along with the process parameters synergistically affected the aflatoxin content in the matrix. The result obtained were in accordance with the result reported by Rustom et al (1993), M endez-Albores et al (2013) and Moreno-Pedraza et al (2015).…”

“…The results obtained for the effect of pH were in accordance with the results published by Méndez‐Albores et al () in which it was stated that as the alkali concentration increased, lower aflatoxin values were registered. Moreno‐Pedraza et al () also have reported that pH values around neutral (pH 8.0 only 19.10%) were much less effective in destroying aflatoxins than more alkaline conditions (at pH 11.8 and 12.5, it was by reduced 90 and 100% respectively).The analysis for the respective optimized parameters proved to be at a closer range to the predicted values. The combination treatment, where the spiked PDA was PEF treated and then subjected to thermal treatment was found to be higher than the individual process effect.…”

“…The pH of the sample or product was vital for both the production (Yu, ) and as well for the reduction of aflatoxin produced/present (Méndez‐Albores, et al, ; Moreno‐Pedraza et al, ). The variable pH range was fixed 4‐10 based on the studies indicating the effect of acidic and alkaline pH on toxin reduction.…”

“…The lower and higher ranges for the variables, pH (4–10), temperature (110–119 °C), and time (10–20 min) for thermal process optimization and pH (4–10), pulse width (4–32 µs) and output voltage (20–65%) for PEF processing optimization were fixed based on the literature and the instrumental limitation. The pH range of the sample was varied based on the earlier studies where it was reported that aflatoxin contamination was found even in low acidic foods (Colak et al, ) and it was also found that pH, both acidic and alkaline range had a great influence on the reduction/degradation of aflatoxin (Méndez‐Albores, Campos‐Aguilar, Moreno‐Martínez, & Vázquez‐ Durán, ; Moreno‐Pedraza et al, ). The thermal process parameters temperature and time was fixed based on the adaptation to the food matrix, where minimal effect on the quality attributes will be desired.…”

An In-Vitro Evaluation of the Capacity of Local Tanzanian Crude Clay and Ash Based Materials in Binding Aflatoxins in Solution

“…Studies show that Alumino-silicates have wide variation of these elements ( Table 1). In South American countries, ashes such as soda ash and wood ash have been used in some food processes such as in niztamalization for corn tenderization where dietary aflatoxins load is also reduced owing to breakage of aflatoxin lactone-ring by the ash alkalinity (19). In Tanzania farmers are using an imported binder that has proven to be useful in terms of protecting livestock from aflatoxin exposure.…”