Browsing by Author "Farawahida AH"

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    Monascus spp. and citrinin: Identification, selection of Monascus spp. isolates, occurrence, detection and reduction of citrinin during the fermentation of red fermented rice
    (Elsevier BV, 2022-10-16) Farawahida AH; Palmer J; Flint S
    Red fermented rice (RFR) is rice fermented using Monascus spp. This product contains monacolin K, providing health benefits including mitigation of diarrhoea and improving blood circulation. RFR can produce pigments that can act as natural colour and flavouring agents. However, Monascus spp. (a fungal starter to ferment RFR) can also produce the mycotoxin, citrinin (CIT) which is believed to have adverse effects on human health. CIT in RFR has been reported worldwide by using different methods of detection. This review focuses on the production of RFR by solid-state fermentation (SSF) and submerged fermentation (SmF), the occurrence of CIT in RFR, CIT quantification, the factors affecting the growth of Monascus spp., pigments and CIT production in RFR, and possible methods to reduce CIT in RFR. This review will help the food industries, researchers, and consumers understand the risk of consuming RFR, and the possibility of controlling CIT in RFR.
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    The relationship between pH, pigments production, and citrinin synthesis by Monascus purpureus during red fermented rice fermentation
    (Elsevier Ltd, 2025-09-01) Farawahida AH; Palmer J; Flint S
    Red fermented rice (RFR) is consumed as a traditional medicine in many countries. Consumption of food contaminated with citrinin (CIT) has adverse effects on the liver cells and the kidneys. This study aimed to understand the relationship between pH, pigments, and CIT levels during the fermentation of RFR. The rice underwent soaking, steaming, and autoclaving before being inoculated with Monascus purpureus isolates (MF1 or MS1) and fermented at 30 °C for 30 days. The difference between these isolates was that MF1 and MS1 required 4 days and 7 days, respectively, to produce light blue fluorescence on Coconut Cream Agar (CCA), an indicator of the presence of CIT. The pH, pigments, and CIT levels were recorded during fermentation using a pH meter, spectrophotometer, and Ultra-High-Performance Liquid Chromatography with a Fluorescence Detector (UHPLC-FLD), respectively. The pH dropped from 6.8 to 5.3 after 9 days of fermentation. The CIT levels increased from day 4 until day 5 and then decreased during the fermentation period. The pigments increased after 5 days of fermentation, suggesting a relationship between pigments production and CIT reduction. Mixing the CIT standards and pigments extracted from MF1 and MS1 (a mixture of yellow, orange, and red pigments) showed that there was a reduction in CIT of 26–68 % and 16−45 %, respectively. It is suggested that future work should determine which pigments are responsible for CIT reduction. The optimization of pigments production with the control of pH at 5.5 may help to control CIT levels during the fermentation of RFR.