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Author: search.filters.author.Wafula, Eliud N.Subject: search.filters.subject.fermentation

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    Phenotypic and genotypic characterization of lactic acid bacteria isolated from spontaneously fermented vegetable amaranth
    (African Journal of Food Science, 2021-05-25) Wafula, Eliud N.; et.al
    Lactic acid bacteria (LAB) are Gram-positive, non-spore-forming, catalase-negative cocci or rod-shaped bacteria that produce lactic acid as a major fermentation product. They are also involved in the production of fermented foods. They have applications in industry and human health, such as food preservation and probiotics. The aim of this research was to isolate, characterize, and classify indigenous lactic acid bacteria from fermented vegetable amaranth, a leafy vegetable native to Africa. The isolates' 16S rRNA gene was amplified using bacterial universal primers 27F and 1492R. From fermented vegetable amaranth, a total of 15 LAB were isolated were grouped into the genera Lactobacillus, Lactococcus, and Weissella based on 16S rRNA gene analyses. Lactobacillus plantarum dominated vegetable amaranth fermentation, accounting for 60% of all isolates.
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    MICROBIAL, CHEMICAL AND SENSORY PROPERTIES OF PINEAPPLE AND BEETROOT JUICE BLEND FERMENTED USING MIXED PROBIOTIC LACTIC ACID BACTERIA CULTURES (LACTOBACILLUS PLANTARUM AND L. RHAMNOSUS)
    (African journal of food, Agriculture,Nutrition and development ajfand, 2025-11-06) Wafula, Eliud N.; et.al
    The rising demand for functional foods has increased interest in probiotic products beyond traditional dairy sources, particularly among individuals with lactose intolerance, dairy allergies, or those adhering to plant-based diets. Fruit juices such as pineapple and beetroot offer promising non-dairy alternatives for delivering probiotic cultures. This study aimed to analyze the microbial, physicochemical, nutritional, and sensory acceptability profiles of pineapple and beetroot juice blends fermented with a mixed culture of probiotic lactic acid bacteria (Lactobacillus plantarum and Lactobacillus rhamnosus). Juice blends were prepared in varying pineapple-to-beetroot ratios: 90:10 (P90:B10), 80:20 (P80:B20) and 70:30 (P70:B30), alongside 100% pineapple (control-P) and 100% beetroot (Br) juices. All blends were pasteurized and inoculated with the probiotic cultures and fermented for 28 days, except the control-P and 100% Br treatment, which underwent spontaneous fermentation. Lactic acid bacteria (LAB) count analysis showed that all inoculated blends maintained probiotic viability (>7 log CFU/mL) for up to 21 days, with the P90:B10 blend maintaining viability up to 28 days. Yeast or mold growth was not detected in the probiotic blends up to day 21, whereas the control-P and 100%Br treatment exceeded yeast and mold count limits by day 14. Physicochemical analysis for all treatments revealed a significant increase in titratable acidity, accompanied by a decrease in pH and sugar content over the fermentation period in the inoculated blends (P90:B10, P80:B20, P70:B30). Significant differences P < 0.05 in vitamin C content were observed between the control-P and all other treatments on day 1. Among the three blends, P90:B10 achieved the highest overall consumer acceptability. Fermenting pineapple-beetroot juice blends with L. plantarum and L. rhamnosus mixed culture is a feasible approach to producing a safe, palatable, and nutritionally beneficial non-dairy probiotic beverage. The P90:B10 blend was optimal in supporting probiotic viability and achieving desirable consumer sensory attributes and, therefore, would be recommended for future commercialization as a probiotic non-dairy product.
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    Effect of Lactic Acid Fermentation on Phytochemical Content, Antioxidant Capacity, Sensory Acceptability and Microbial Safety of African Black Nightshade and African Spider Plant Vegetables
    (BACTERIA MDPI, 2023-02-11) Wafula, Eliud N.; et.al
    Traditional preparation of African indigenous vegetables (AIVs) such as African black nightshade (Solanum nigrum) and African spiderplant (Cleome gynandra) involves either boiling and discarding the first water or lengthy boiling. Fermentation is considered a better alternative processing technique due to the enhanced retention of phytochemical contents and sensory properties. However, little is known about the impact of lactic acid fermentation on the phytochemical content, antioxidant capacity, sensory acceptability and microbial safety of the African black nightshade and African spiderplant. This study aimed to ferment AIVs using combined starter cultures (Lactobacillus fermentum and Lactococcus lactis) and further determine their effect on the phytochemical content (phenolic compoundsandflavonoids), antioxidantcapacity, sensory acceptability and microbial safety of the vegetables. There was a marked increase in phenol and flavonoid contents in all fermented vegetables (p < 0.05). The starter-culture-inoculated African black nightshade, while flavonoid content was 10.6 mg/g QE (quercetin equivalent) in the same. Starter-culture-inoculated AIVs presented significantly higher antioxidant capacity with a 60–80% radical scavenging activity compared to levels in uninoculated batches (p < 0.05). Fermented vegetables were more liked than the boiled vegetables and were microbiologically safe. In conclusion, lactic fermentation of AIVs increased phytochemical contents (phenolic compounds and flavonoids), maintained antioxidant capacity and improved product safety and sensory acceptability. Therefore, fermentation and consumption of the African indigenous vegetables are to be encouraged