With the current global surge in diabetes cases, there is a growing interest in slowing and managing diabetes and its effects. While there are medications that can be used, they have adverse side effects such as hypoglycemia and weight gain. To overcome these problems, bioactive compounds commonly found in fruits, vegetables and cereal grains are used to slow starch digestion and transport of simple sugars across the intestinal epithelia thereby reducing plasma blood glucose spike. These effects are achieved through inhibition of amylases, glucosidases and glucose transporters present in the gastrointestinal tract and brush boarder membrane. The extent of inhibition by polyphenols is dependent on molecular structure, doses and food matrix. Glycemic lowering effect of polyphenols have been demonstrated both in in vivo and in vitro studies. However, when these compounds are incorporated in food systems, they can interact with other polymers in the food matrix leading to lesser inhibition of digestion and/or glucose transporters compared to isolated or pure compounds as often witnessed in most in vitro studies.

Fermentation of cowpea milk was carried out using three mixed starter cultures containing (i) Lactobacillus acidophilus, Bifidobacterium spp, and Streptococcus thermophilus (ABT) (ii) Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus (DT) or (iii) Lactobacillus rhamnosus GR-1 and Streptococcus thermophilus (GT). Proximate composition of raw and fermented cowpea milk was determined using the AOAC methods. Lactic acid bacteria survival and sensory attributes of the fermented cowpea milk was also determined. Crude fat decreased significantly (P<0.05) after fermentation except for GT culture which led to 33.2% increase. Crude fiber was not detected in all the samples. Fermentation with GT also led to increase in protein content, although this was not significant. A decrease was observed for carbohydrate content, after fermentation, with DT culture leading to the highest decrease of 7.1%. There was a general increase in microbial growth during the first two weeks of storage (refrigeration at 4˚C). Thereafter the number reduced to Log10 4.11 cfu/ml on the 28th day of storage. No significant differences were observed for sensory attributes of taste, texture and overall acceptability. However, aroma and appearance had significant differences among the samples (P<0.05). The study demonstrated that nutritional quality of cowpea milk can be achieved through fermentation. Also, cowpea milk fermented with lactic acid bacteria produce a yoghurt-like product that can be sweetened to taste and be acceptable to consumers. The study therefore recommends that more work should be done to improve the sensory acceptability of the products and that their potential health benefits should be determined through in vivo studies.

Street-vended foods are a major threat to public health because of their microbial contamination. This study investigated hygiene practices and microbial contamination of street foods in Kenyatta University’s environs. Both cross-sectional and experimental designs were adopted. Four (4) major vending stalls at the main entrance to Kenyatta University, gate (A) and at the hind gate at KM shopping center were identified for this study. Twelve (12) food samples were collected from these stalls; sausages, samosas and kachumbari. The foods were collected and transported in cooler boxes to the Microbiology Laboratory at Kenyatta University within 3 hours for analyses. Standard microbiological methods were used for enumeration of Salmonella, coliforms and Escherichia coli. No Salmonella was detected per 25g in all food samples tested. Fifty percent (50%) of kachumbari samples tested positive for E.coli whereas samosas and sausages tested negative. Kachumbari, from all vending stalls, had total coliform levels 4.12 log10 cfu/g, 4.26 log10 cfu/g and 4.21 log10 cfu/g, that did not meet the quality standards (4.00 log10 cfu/g) for ready-to-eat foods. Total coliform counts were below detection limits in samosas and sausages. All (100%) the stalls were exposed to potential contaminants: 75% of the vendors did not wear protective clothing, they handled money and sold food simultaneously, and polythene bags exposed to open air, were used for packaging take away rations. All the foods evaluated were safe for human consumption except kachumbari. Policies on safe street food to be enforced and education and training of vendors on environmental and personal hygiene to be strengthened.

High prevalence of protein-energy malnutrition among the vulnerable population, especially children has prompted research on fortification of common staple cereal foods such as rice. However, rice has inferior nutritional value compared to other popular cereals, such as maize, therefore limiting its full utilization. Its storage protein, glutelins, is not easily digested by monogastric animals; therefore, food to food fortification of rice flours provides protein nutritional compensation as well as improvement of other nutrients. This study was carried out to determine the proximate and mineral (Fe, Zn, Mg, Ca, P) composition of rice composite flours. Methodology: The blending ratios (rice: maize: sorghum: pumpkin: carrots: baobab: amaranth) used in the study were 70:0:0:7.5:7.5:5:10 (AT1), 45.5:24.5:0:7.5:7.5:5:10 (AT2), 35:35:0:7.5:7.5:5:10 (AT3), 23.3:23.3:23.3:7.5:7.5:5:10 (AT4) and 100% rice flour (AT5). Proximate analyses were performed according to Association of Official Analytical Chemist (AOAC) methods. Atomic absorption spectroscopy was used to determine the minerals. Data analysis was done using Analysis of Variance (ANOVA). Mean comparisons for treatments were done using Bonferroni tests and significance level was set at P≤0.05. Findings: Moisture content of the composite flours ranged from 10.87 to12.55% and was significantly different (p<0.05). Ash content was not significantly different (p<0.05) and ranged between 1.08 and 1.85%. The fat content ranged between 5.38 and 10.67%; with AT4 having the highest and AT5 having the least fat content. The carbohydrate content was significantly (p<0.05) different among the flour; ranging between 66.65 and 73.51%. Crude fibre ranged between 1.42 and -2.20%, whereas the protein content ranged from 6.88 to 7.73%. Iron content ranged between 0.06 and 0.08 mg/100g zinc ranged from 0.19 to 0.56 mg/100g. The phosphorus content ranged from 0.07 to 0.18 mg/100g with no significant (p<0.05) difference. The calcium content was significantly (p<0.05) different among the flours and ranged from 1.41 to 1.91 mg/100g. Conclusion: The results show that the flour composites have the potential to improve nutritional status of consumers. Thus, consumption of AT1, AT4 and AT5 composite flours with a protein content of 7.3%, 7.7% and 7.4% maybe recommended for children aged 6 - 59 months in order to prevent protein-energy malnutrition.

Today, there are several attempts to make nutritious food products low in glycemic carbohydrates as this can partly help in solving the ever-growing numbers of type 2 diabetes and obesity. We thus made two types of jam, one using conventional sucrose with a high glycemic index and the other using honey which is regarded as a low glycemic index carbohydrate.  Honey jam had comparable physical properties with sucrose jam. The total soluble solid (Brix) was significantly lower in honey jam than in sucrose jam (p=0.04) indicating less sugar in honey jam. Both jams had comparatively higher percent moisture content than other jams reported in literature potentially suggesting reduced storage stability. Despite having higher water activity, honey jam had progressive decrease in microbial colony counts suggesting honey was inhibitory to growth of microorganism compared to sucrose jam. This effect was independent of water activity as sucrose jam which had lower water activity promoted growth of microorganism during storage. Therefore, substituting natural honey for sucrose during formulation of tomato jam retards microbial growth thereby prolonging shelf life.