The microbial properties of food are important quality characteristics of food materials as it relates directly with the health of the consumer. This study examined the microbiological properties of high quality cassava flours produced from low postharvest physiological deterioration (PPD) cassava. Wholesome four varieties of yellow-fleshed Low PPD cassava and one variety of high PPD cassava were, peeled, washed, grated, pressed, pulverized, flash dried at 120 °C for 8 minutes, milled with cyclone hammer mill fitted with a screen of 250 µm aperture size, cooled and packed into high density polyethylene bag. The high quality cassava flours produced were analyzed for total viable fungal and bacteria count, fungi isolated were further characterized and identified using molecular methods. Data obtained were subjected to one way analysis of variance (ANOVA) using SPSS 25.0 and significant means were separated applying Duncan multiple range test. The mold count ranged from 1.50±0.71 - 2.50±0.71 cfu/ml, with flour produced from IITA-TMS-IBA-011371 and TMEB 419 having the lowest count while the highest was recorded in IITA-TMS-IBA-011368, respectively. The yeast count ranged from 1.00±0.00 - 2.0±0.00 cfu/ml, with flours produced from IITA-TMS-IBA-070593 and IITA-TMS-IBA-011371 having the lowest count while the highest was recorded in flour from IITA-TMS-IBA-011368, respectively. The total viable bacterial and fungal count (microbiological quality) of the flours prepared from IITA-TMS-IBA-011368, IITA-TMS-IBA-070593, IITA-TMS-IBA-011412, IITA-TMS-IBA-011371 and TMEB 419 cassava varieties were within the permissible limit of the microbial load of food allowed for human consumption according to the Standard Organization of Nigeria and CODEX alimentraius.

The pertinent information generated from studying quality characteristics such as the structure and crumb properties of baked food products such as bread, cake etc. is very critical as it enhances product quality and inevitably help improve consumer acceptability. This research was carried out to assess the sensory qualities and investigate the microstructural properties of cakes made with high quality cassava flour (HQCF) from selected varieties of low postharvest physiologically deteriorated (PPD) cassava. Wholesome four varieties of yellow-fleshed Low PPD cassava and one variety of high PPD cassava were processed into high quality cassava flour flowing unit operations such peeling, washing, grating, pressing, pulverization and eventual drying using flash dryer operated at 120 °C for 10 minutes followed by milling with cyclone hammer mill fitted with a screen of 250 µm aperture size; the HQCF was allowed to cool, sieved and then packed into high density polyethylene bag. The cakes were analyzed for sensory and microstructural properties. Analysis of variance was performed on the data generated while significant means were separated applying Duncan Multiple Range Test using Statistical Package for Social Sciences (SPSS version 25.0). Generally, there was no significant difference (p≥0.05) in the sensory qualities (Color, texture, aroma, taste, flavor and overall acceptability) of the cakes made. The cake samples had sensory scores with ranges: (2.20 – 3.40), texture (2.60 – 4.10), aroma (2.90 – 4.20), taste (3.10 – 3.80) favor (2.90 – 3.80) and overall acceptability (2.90 – 3.70). The most preferred cake sample was C-070593 (cake sample baked with HQCF from IITA-TMS-IBA070593 cassava. Microstructural properties of cake baked with wheat flour was significantly different from cakes baked with HQCF from low PPD cassava owing to water absorption capacity, starch gelatinization characteristics and dough composition such as gluten quality. Cakes of acceptable sensorial and microstructural characteristics similar to that made with 100% wheat flour were produced with HQCF from selected varieties of low PPD cassava.

This study was conducted to determine the antimicrobial effect of Lactic acid bacteria on food-borne pathogens isolated from some fruits sold in Ibadan, Nigeria. Lactobacillus species isolated from healthy fruits include L. casei, L. brevis, L. desidosus, L. jenseni, Lactiplantibacillus plantarum and Fructilactobacillus spp. while Aeromonas hydrophylia, Enterobacter aerogene, Escherichia coli, Salmonella typhii, Shigella dysentriae, Pseudomonas fluorescens, Bacillus megaterium, Candida valida, Saccharomyces cerevisiae, Rhizopus stolonifer were isolated from spoilt fruits using pour plate technique and biochemical test. Gram-negative isolates were 100% resistant to Cefuroxime, Amoxycillin/Clauvulanate, and Ampicillin while 93.75% of the isolates were highly sensitive to Ofloxacin. Gram-positive isolates were 100% resistant to Cloxicillin and highly sensitive to Ofloxacin and Gentamycin using an antibiotic disc. Lactiplantibacillus plantarum had the highest amount of Lactic acid (5.6 g/l) while L. casei had the lowest yield (3.6 g/l) at 48 hours. L. casei had the highest amount of hydrogen peroxide (0.00036 g/l) while Lactiplantibacillus plantarum. and Fructilactobacillus spp. had the lowest yield (0.00021 g/l) at 48 hours. The highest amount of diacetyl (3.01 g/l) was produced by L. jenseni while the lowest amount was observed in L. brevis (0.43 g/l) at 48 hours. The maximum inhibitory activity was observed in L. brevis against B. megaterum with a diameter of 18mm zone of inhibition while the minimum activity by L. desidosus, L. jenseni, Fructilactobacillus spp. was observed against B. subtilis and Lactiplantibacillus plantarum against K. pneumoniae with diameter 8 mm zone of inhibition. The antimicrobial compounds produced by the Lactic Acid Bacterial had antimicrobial effects on food-borne pathogens.

The functional, rheological and color (physical) properties of flours are quality attributes determining the usage, suitability and organoleptic characteristics of flours meant for industrial (baking and confectionery) application. This study investigated the functional, physical and rheological properties of composite cassava-wheat flour produced with low (PPD) cassava flours. Wholesome four varieties of yellow-fleshed Low PPD cassava and one variety of high PPD cassava were, washed, grated, pressed, pulverized, flash dried at 120 °C for 8 minutes, milled with cyclone hammer mill to which a screen having aperture size of 250 was affixed and subsequently cooled. The flours were subjected to analysis such as physical (color), functional and rheological. SPSS 25.0 was used to analyze pertinent data generated, significant means were separated applying Duncan multiple range test. The composite cassava-wheat (CCW) flours’ water absorption, swelling power, solubility index, oil absorption, bulk density, lightness (L*), redness (a*), and yellowness (b*) ranged from 13.53±0.05-13.73±0.05%, 7.00±0.01-8.87±0.03%, 8.27±0.01-9.55±0.06, 101.33±0.87-118.83±0.49%, 0.55±0.01-0.62±0.01 g/cm3, 93.95±0.28-96.01±0.34, 0.36±0.01-0.77±0.10 and 9.94±0.17-11.74±0.24, respectively. The water absorption, dough development time, dough stability, mixing tolerance index, dough consistency, farinograph quality number, breakdown time, water absorption for default moisture content and gluten content ranged from 60.70±0.00-63.70±0.14%, 1.28±0.00-1.32±0.00 min, 1.14±0.00-1.37±0.00 min, 75.00±0.00-104.00±0.00 BU, 424.00±0.00-518.00±0.00 mm, 23.00±0.00-26.00±0.00 mm, 2.10±0.00-2.38±0.00 min, 59.90±0.00-62.20±0.00% and 27.00±0.00-32.00±0.00, respectively. Comparable functional, rheological and physical properties to that of wheat flour was obtained from CCW flour prepared with blend of low PPD cassava flour and wheat which are suitable for application in the baking and confectionery industry.