Development of Finger Millet-amaranth Based Weaning Porridge Flour Enriched With Edible Cricket Scapsipedus Icipe

Abstract

Globally, there is growing interest to integrate nutrient–dense foods such as insect flour into food products to achieve nutritional goals and address food insecurity. Though cereal–based porridge is widely consumed in many sub–Saharan African countries, there is a lack of information on its enrichment with edible cricket, Scapsipedus icipe. The objective of this study was to develop and determine the nutritional composition, anti–nutrient content, sensory acceptability, microbial safety and storage stability of porridge flour formulations enriched with edible cricket. Porridge was prepared from the flour formulations with a cricket content of 0%, 10%, 15% and 20% (w/w). A sensory evaluation pretest, indicating 10% cricket-finger millet-amaranth flour as the most desirable porridge, informed the basis of using 10% cricket, 60% finger millet, and 30% amaranth for the preparation of four porridge flour samples, using traditional processing methods: germination, fermentation and roasting. Untreated formulation and an existing finger millet-based commercial porridge flour served as control. Cricket enriched formulations had high protein (2–folds), crude fat (3.4–4–folds) and energy (1.1–1.2–folds) compared to the commercial flour. Processing by germination and fermentation resulted in high phytic acid degradation (67% and 33% respectively) and improved mineral bioavailability. The iron content of the formulated flours ranged from 8.6–19.5 mg/100 g with the germinated sample having the highest content (19.5 mg/100 g). Zinc content was in the range of 3.1–3.7 mg/100 g while the range obtained for calcium was from 234.9 mg–278.6 mg/100 g. The commercial flour recorded zinc and calcium contents of 1.86mg/100g and 312.7mg/100 g respectively. Cricket enriched formulations had significantly (p < 0.05) higher content of vitamin B12, vitamin B5, vitamin B6, nicotinamide and thiamine when compared to the commercial flour. A total of 44 fatty acids methyl esters (FAMEs) were detected in the porridge flour oil extract using Gas Chromatography coupled to Mass Spectrometry (GC– xiii MS). Of the 24 saturated fatty acids (SFAs) detected, Methyl hexadecanoate (palmitic acid) contributed the highest proportion followed by Methyl octadecanoate (stearic acid) across the flour samples. In addition, Methyl 9E–octadecenoate (oleic acid) was the predominant monounsaturated fatty acid (MUFA) whereas Methyl 9Z, 12Z–octadecadienoate (linoleic acid, LA) contributed the highest proportion of the polyunsaturated fatty acids (PUFAs). Αlpha–linolenic acid (ALA) was detected in all the cricket-enriched samples while docosapentaenoic acid (DHA) was only present in the fermented sample. Fermentation process caused a significant (p < 0.05) increase in the levels of PUFAs (30%) and MUFAs (14%) and a decrease in the SFAs (3%) while roasting process caused a significant (p < 0.05) increase in both MUFAs and SFAs by 27 and 10%, respectively. Total flavonoids were reduced during germination (42%) and roasting (10%) but increased during fermentation (13%), while tannin content decreased during germination (29%). Panelist–based sensory evaluation revealed significant differences (p < 0.05) among the porridge samples. Results suggest cricket formulations at 10, 15 and 20% were all acceptable with significant variations. 10% cricket formulation had the highest scores for all attributes. On the effect of processing, roasted and fermented samples had the highest sensory scores compared to the germinated porridge sample with the least overall acceptability score. The total viable plate count for the formulations ranged from 2.4 to 4.1 log10 CFU/g, whereas mold and yeast count was in the range of 1.4 to 1.7 log10 CFU/g. Roasted flour formulation had low counts of bacteria, yeasts and mold and low moisture content. The flour formulations packaged in paper bags exhibited higher variations in terms of microbial loads and moisture content as compared to those packaged in aluminium bags. This observation shows that enrichment combined with proper processing may improve the nutritional quality of cereal–based foods and reduce the levels of anti-nutrients. High sensory

rating and low microbial count confirm that cricket flour can be used as an effective functional ingredient to enrich porridge flour.