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ABSTRACT Aflatoxins, toxic mold metabolites, are naturally contaminants of food and have been reported on tea ( Camellia sinensis), but there are no validated methods published for its determination. A method has been standardized incorporating Tween-20, a nonionic surfactant in the extraction solvent, with use of an immunoaffinity column for cleanup followed by postcolumn photochemical derivatization reversed-phase high-performance liquid chromatography. Acceptable recoveries of 76-100% were observed when spiked with aflatoxins B1, B2, G1 and G2. Analysis of market samples of black tea showed the presence of aflatoxigenic molds in 25.9% of samples, and aflatoxin B1 was detected in one sample at a level of 19.2 µg/kg. Aflatoxin production was observed in tea samples artificially inoculated with the conidia of an aflatoxigenic strain of Aspergillus flavus. Major portion of the aflatoxins added to the tea leaves remains in the residue when boiled with water, and 30.6% gets partitioned into the filtrate, which is the component used to prepare the beverage. PRACTICAL APPLICATION Tea ( Camellia sinensis) beverage is widely consumed in the world. This manuscript discusses the prevalence and problems of aflatoxigenic molds and aflatoxins in black tea. A new protocol has been validated for determination of aflatoxins using a surfactant in the extraction solvent for better extraction, followed by column cleanup using immunoaffinity columns and quantification by postcolumn photochemical derivatization reversed-phase high-performance liquid chromatography. Aflatoxin production in tea artificially inoculated with the conidia of Aspergillus flavus (isolated in the laboratory) was also observed. The method of preparation of tea beverage by a large number of people in the country is by boiling the black tea leaves with water and using the filtrate to prepare the beverage with milk and sweetener. In the study on the partitioning of the aflatoxins added to black tea leaves before boiling, it was observed that about 30.6% of the added toxin is in the filtrate, a finding with relevance in risk assessment. [ABSTRACT FROM AUTHOR]

Burfi, an Indian milk-based sweet, is susceptible to microbial spoilage that restricts its shelf life to 10 days.Large-scale marketability ofburfiand its export potential requires longer shelf life.Therefore, our aim was maximizing shelf life by packaging means. Studies were carried out onburfiin different packaging materials under different atmospheres– normal packing, vacuum packing and use of a free-oxygen absorber– at 65% RH/27C. Normal packing even in barrier film did not effectively control microbial spoilage. Vacuum packing, although it retarded microbial growth, adversely affected texture and sensory quality. A free-oxygen absorber coupled with high-barrier materials like metallized films/foil laminates offered more than 45 days shelf life. Stored samples could be grouped by principal component analysis. The major sensory attributes contributing to grouping were color, firmness, chewiness, creamy and rancid notes. Sensory firmness and chewiness were found to have good correlation with instrumentally measured texture values. [ABSTRACT FROM AUTHOR]

Abstract: Aflatoxin M1 (AFM1) is a toxic metabolite found in the milk of lactating animals which have consumed feedstuffs contaminated with aflatoxin B1. Ultra high temperature treated (UHT) milk is a product which is becoming popular in developing countries like India as there is a lack of proper cold storage or refrigeration facilities. In this study, 45 samples of UHT milk of popular brands prevalent in the market were analyzed for the presence of AFM1 by reversed phase HPLC using fluorescent detector after cleanup of sample with immunoaffinity columns. All samples of plain UHT milk were positive for AFM1 and 38% of these contained levels more than 0.5μg/kg, the maximum permitted limit prescribed by the Codex Alimentarius Commission and by the mandatory regulations of the country, the FSSAI Regulations, 2011. In 62.5% of flavored UHT milk, AFM1 was below detectable levels (0.02μgL−1). However, 12.5% of these samples also contained levels exceeding the maximum permitted limits. AFM1 was present in 61.6% of the 52 raw milk samples analyzed from the two states of Karnataka and Tamilnadu with a range of 0.1–3.8μgL−1. 17.3% of these samples also exceeded the regulatory limits of the country. [Copyright &y& Elsevier]