Microbial Load, Aflatoxins and Histamine with Processing and Storage of Termite Flour
DOI:
https://doi.org/10.47604/ijf.3792Keywords:
Termites Store, Oven Drying, Sun Drying, Microbial Load, Histamine, AflatoxinsAbstract
Purpose: The current population growth directly translates to an increased strain on the existing food resources. The increasing population needs a sustainable supply of food, especially proteins. However, given that much of the protein required is sourced from livestock that is straining on the environment, unconventional protein sources that are less strenuous, like edible insects, need to be sought. In many regions of the globe, consumable insects have attained more attention as a viable animal protein source. The majority of edible insects are gathered from their natural habitats, although semi-taming and enclosed farming is gaining popularity. However, when stored, insects and processed insect foods like flour may develop aflatoxins and microbial growth. This study assessed microbial load, aflatoxin B1, and histamine levels in flours of termites found in western Kenya.
Methodology: The assessment was through laboratory procedures of the levels as a function of processing and time of storage for three months. Determination of microbial load was done by incubating the samples at room temperature. The yeast plates were removed after twenty-four hours, and mold and bacteria plates removed after seventy-two hours after which colonies were counted. The extraction of aflatoxins involved using methanol mixed with small amounts of water (seventy percent methanol). Histamine was determined using an enzyme-linked immunosorbent (ELISA), a protein-based protocol.
Findings: The study found processing to eliminate histamine in termites. Aflatoxins levels were high in oven-dried samples. Microbial loads were not detected in any of the samples refrigerated at 3˚C, whereas for the bench samples, oven drying was found to eliminate bacteria, yeasts, and molds in whole termites. All insect samples exhibited statistically significant differences (p<0.0001), implying that processing impacted histamine, aflatoxin, and microbial load levels. The termite samples had significant differences (Sig < 0.001) in the concentration of aflatoxin in the storage period. There was a sharp rise in aflatoxin concentration in most samples within the first 30 days of storage, indicating ideal conditions for fungal growth in this period. Mold counts declined with time in room-temperature samples, while refrigerated samples started manifesting at day 30 and decreased through to the 90th day. Bacterial counts for both the bench and refrigerated insect samples fluctuated throughout the storage duration but were found to be within the legislated limits for minced meat. Yeasts under bench condition displayed a decline in the first 60 days, followed by a pronounced increase towards the end of the 90-day storage duration, whereas refrigerated samples showed increasing yeast levels. Processing and storage affect histamine, aflatoxin, and microbial loads, affecting their growth, survival, and overall stability. Oven dried samples indicated lowest levels of infection for most of the parameters under the study. Refrigerated samples were least infected by microbes.
Unique Contribution to Theory, Practice and Policy: Optimizing processing and preservation methods is vital for maintaining food safety, extending shelf-life, and ensuring product quality to protect consumer health.
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