Many people around the globe prefer bottled water especially in developing countries, where tap water is not drinkable. This study investigated the quality of bottled drinking water sold in Lilongwe city, Malawi. Compliance with Malawi Standards (MS) 560 (2004) for natural mineral water, MS 699 (2004) for bottled water and the World Health Organisation guidelines for drinking water were examined. Bottled water from different 12 brands was purchased from local stores and analysed for its pH, total dissolved solids (TDS), EC, turbidity, Ca, Mg, Na, K, Fe, NO3−, Cl−, F−, SO42−, hardness, alkalinity, and Escherichia coli. A Hierarchical Cluster Analysis (HCA) resulted in two clusters in which most of the brands (92%, n = 12) belonged to one group. The two clusters and significant differences (ANOVA p < 0.05) in chemical compositions among the brands were attributed to the variations in the water source and the treatment processes. The results showed that 10 brands did not comply with the MS 699 (2004) turbidity standard (1 NTU) and the pH of one of the brands was below the minimum MS 699 (2004) standard of 6.50. This research showed that 12 brands had bottle labelling errors and discrepancies in chemical composition. The article highlighted the need for a strict inspection from the responsible governmental ministry to improve water quality and to adjust water bottles’ labels according to water characteristics.

This study was performed as a follow-up to a study from 2013, to assess the impact of management interventions on aflatoxin incidence and levels in commercial groundnut products in Malawi. Sixtyseven samples of commercial groundnut products were analyzed for aflatoxin using a fluorometric method. Total aflatoxin levels ranged from 1.5 to 1200 lg/kg in raw groundnuts and 83-820 lg/kg in groundnut flour from vendors. In branded groundnut flour and peanut butter from supermarkets, aflatoxin levels ranged from 13 to 670 lg/kg and 1.3 to 180 lg/kg, respectively. About 93, 88, 78 and 72% of the samples analyzed contained aflatoxin levels above regulatory limit used in Malawi (3 lg/kg), EU (4 lg/kg), most developing countries (10 lg/kg), and the USA (20 lg/kg), respectively. Despite much effort, aflatoxin levels remain persistently high in commercial groundnut. Considering the difficulty of achieving an efficient government regulation system due to resource constraint, the authors recommend the promotion of a socially responsible groundnut processing industry that has consumer welfare as its central feature.

Aflatoxin contamination and biodeterioration were examined in 302 samples of dry cowpeas and pigeon peas that were randomly purchased from 9 districts of the Southern Region of Malawi during July and November 2015. Further, the impact of flotation/washing on aflatoxin levels on the pulses was elucidated. Aflatoxin analyses involved immunoaffinity column (IAC) clean-up and HPLC quantification with fluorescence detection (FLD) while legume biodeterioration assessments were done by visual inspection. Aflatoxins were frequently detected in cowpea (24%, max., 66 μg/kg) and pigeon pea (22%, max., 80 μg/kg) samples that were collected in the month of July. Lower aflatoxin incidence of 15% in cowpeas (max., 470 μg/kg) and 14% in pigeon peas (max., 377 μg/kg) was recorded in the November collection. Overall, aflatoxin levels were significantly higher in the pulses that were collected in November. However, there were no significant differences in the total aflatoxin (aflatoxin B (AFB) + AFB + AFG + AFG) levels between the two types of pulses. Remarkably, in 76.2% of the aflatoxin positive cowpea and in 41.7% of the aflatoxin positive pigeon pea samples, aflatoxin G concentration exceeded aflatoxin B Insect damage percentage averaged at 18.1 ± 18.2% (mean ± SD) in the cowpeas and 16.1 ± 19.4% in pigeon peas. Mean discolouration percentage (number of pulses) of the cowpeas and pigeon peas was found to be at 6.7 ± 4.9 and 8.7 ± 6.2%, respectively. Washing and discarding the buoyant fraction was highly efficient in reducing aflatoxin levels; only 5.2 ± 11.1% of the initial aflatoxin level was found in the cleaned samples. In conclusion, cowpeas and pigeon peas sold on the local market in Malawi may constitute a hazard especially if floatation/washing step is skipped.

Timely drying of groundnuts is important after harvest. In most parts of sub-Saharan Africa, moisture content reduction is practically achieved by solar drying. In particular, the groundnuts are traditionally cured in the field using the inverted windrow drying technique. Recently, the Mandela cock technique, a ventilated stack of groundnut plants with a chimney at the center, has 2 been introduced in the southern Africa region with the aim of reducing moisture content and the risk of aflatoxin contamination. An on-farm study was conducted in Malawi to compare the effectiveness of the Mandela cock and Windrow drying techniques with respect to aflatoxin control. For two consecutive years, farmers (2016, n=29; 2017; n=26) were recruited to test each of the two drying techniques. A mixed-design ANOVA showed that the Mandela cock groundnut drying technique led to significantly (p<0.001) higher aflatoxin levels in groundnut seed compared to the traditional inverted windrow drying (5.7 μg/kg , geometric mean vs 2.5 μg/kg in 2016 and 37.6 μg/kg vs 8.4 μg/kg in 2017). The present findings clearly demonstrate the need for regulation and technology validation if farmers and consumers are to benefit.