Asian Food Science Journal

Aims: Rice-based ready-to-eat extruded snack was developed by incorporating the rice flour with kidney bean, fermented surgum and unfermented sorghum flours with the sole aim of accessing the effect of the addition of the kidney bean and sorghum on the nutritional quality of the extruded snack developed.

Methodology: Rice-dried kidney bean composite flours were supplemented with fermented and unfermented sorghum grains were optimized using optimal design model of response surface methodology; the dependent variables were the proximate and mineral compositions. The extrusion process was also optimized using central composite design of response surface methodology. The sensory evaluations of the extrudates were carried out.

Results: The result of the product optimization of the composite flours gave the R-squared and adjusted R-squared of the ash, crude fibre and crude protein to be between 0.9961 and 0.9987. R-squared and adjusted R-squared close to unity is an indicated of statistical model that is fit, and hence, show that the independent variables support the dependent variables strongly. So, we can deduce that the independent variables strongly supported the ash, crude fibre and crude protein contents. The extrusion results showed that screw speed was the most potent factor required for the extrusion process, followed by temperature. Sample 19 having independent variables of 21.7% screw speed, 80^oC temperature and 105 rpm resulted in extruded snack with the highest overall sensory acceptability.

Conclusion: Acceptable snacks with over 70% sensory qualities were developed. Addition of fermented sorghum flour resulted in composite flour with protein content were well above 100%.

Aim: The main objective of the study is to assess the vendor and environmental hygiene, microbial contamination of deep-fried tilapia sold, and the quality of the oil used in the streets of Kasarani sub-county

Study Design: Cross-sectional study.

Place and Duration of Study: Kasarani Sub-county and The University of Nairobi Department of Food Science, Nutrition, and Technology laboratory between January 2019 to July 2020.

Methodology: Structured questionnaires, checklists, analytical observations, and market observations were used to collect data from the street vendors. After the collection of the fish samples, microbial analysis of the fish samples was carried out using standard methods for Total coliforms and Staphylococcus aureus. The deep-frying oil was sampled for analysis of color and viscosity. Results were evaluated using national standards.

Results: The findings indicated that all the vendors have received a basic education and that all vendors fall under the low-income group. The most contaminated part of the fish by Staphylococcus aureus and total coliforms is the gills. The highest contamination was from Clay city ward (2.46 ± 0.43) while the least contaminated was from the Mwiki ward (1.28 ± 1.17). The total coliforms and Staphylococcus aureus concentration are significantly different between wards p (<0.05) as the p-value was 0.003 and 0.043 respectively.

Conclusion: The findings indicate that the vending practices carried out are unsanitary. The fish as sold were contaminated with total coliforms and Staphylococcus aureus at high levels indicating poor hygiene procedures. The environment is characterized by poor sanitation and hygiene. The oil used for deep frying was characterized by dark color and high viscosity indicating prolonged usage of the same oil. Policies governing street vending and the environment should be reinforced to prevent the occurrence of hazards resulting from street vended fish.

The microbiological, physico-chemical, sensory and storage characteristics of dambu-nama (DN) as influenced by addition of citric acid, salt and sugar as hurdles were investigated. Preliminary sensory evaluation suggested that at citric acid level above 0.3%, sugar and salt levels above 2% each, the products were either too harsh or sweet for acceptance. Four products comprising DN with 0.1% citric acid + 2% salt and 2% sugar (DNC_0.1), DN+ 0.2% citric + 2% salt + 2% sugar (DNC_0.2), DN + 0.3% citric acid + 2% salt + 2% sugar (DNC_0.3) and a control DN without citric acid , salt or sugar (DNC₀) were produced and subjected to microbiological, sensory and storage analyses. Treatment of dambu-nama with the hurdles resulted in significant (p< 0.05) decrease in total plate and mould counts. Thiobarbituric acid, tyrosine and total plate counts varied very little with no definite trend, there by ruling out their use as possible indices of quality. The pH of dambu-nama exhibited a slow but definite decline with storage. The decrease in pH was best described by first order reaction kinetics (r² ≥ 0.987) and adequately by the Arrhenius activated energy complex theory (r² ≥ 0.991) with activation energies (kJ/mol) of 32.6 (DNC₀), 27.6 (DNC_0.1), 23.1 (DNC_0.2) and 54.5 (DNC_0.3), respectively. Treatment with the hurdles increased shelf-life of dambu-nama by a factor of 2.3 to 8.4 with shelf-life (wks) of 7.7 to 4.3 (DNC₀), 17.8 to 10.3 (DNC_0.1), 33.3 to 21.0 (DNC_0.2) and 64.9 to 27.9 (DNC_0.3), respectively for storage at 20 to 35^oC. The objective of this study thus was to investigate quality changes in dambu-nama during normal and accelerated storage as influenced by the hurdles with the purpose of shelf-lives predictions.

The effects of pawpaw (Carica papaya) seed flour addition to wheat based bread was studied. Matured, ripen pawpaw fruits were washed, and the seeds were collected, extracted, dried and milled. Different proportions of wheat and pawpaw seed flour with increasing level of pawpaw seed flour at 0, 2.5, 5, 7.5, 10 and 12.5% addition in wheat were prepared. Control sample was 100% wheat flour and its bread. The functional properties of the flours of wheat and pawpaw seed were determined. The proximate composition (breads and pawpaw seed flour), vitamins content and sensory attributes of the bread samples were determined using standard procedures. The GENSTAT Statistical Software (version 17.0) was used for data analyses. The Data obtained showed an increased oil absorption capacity (0.62-1.23 g/g), foaming capacity (14.54-19.88%) and a decreased water absorption capacity (1.88-1.35 g/g) and bulk density (0.78-0.41 g/cm³) with increased pawpaw seed flour addition. The proximate composition of the bread samples showed significant (p<0.05) increase in moisture (23.80-30.83%), ash (0.78-3.00%), crude fibre (0.58-1.48%), crude fat (2.20-9.68%) and crude protein (11.46-17.71%) but decrease in carbohydrate (61.19-37.31%) contents with increased pawpaw seed flour addition. The pawpaw seed flour showed proximate composition of 8.15% moisture, 7.46% ash, 5.44% crude fibre, 25.41% crude fat, 28.18% crude protein and 25.38% carbohydrate. Vitamin C (0.57-12.95 mg/100 g) and pro-vitamin A (0.26-7.37 µg/100 g) significantly (p<0.05) increased with increased pawpaw seed flour percentage while Vitamin B₃ decreased with increased addition. Appearance and taste panel scores indicated that up to 5% addition of pawpaw seed flour was acceptable in bread formulation.

The present study was performed to get a product loaded of nutrients in terms of protein, amino acids, vitamins, and antioxidants. The product had been made from mixtures of carrot and quinoa puree with mixing ratios 10%, 20% and 30% to reach the highest nutritional value and the best general palatability for the consumer. Carrot puree blends were analyzed for nutritional, chemical, microbial and sensory properties. It was found that by increasing the mixing ratio of quinoa with proportion of carrot the protein ratio reached 5.959 gm/100gm in blend (4) compared with 1.845gm/100 gm in blend (1). The best and highest results were in terms of protein and amino acids, especially essential ones, carrot quinoa puree in comparison with control indicated increase in minerals such as calcium 47.666 mg/100gm and iron 6.107 mg/100gm in blend (4) compared with the control were 35.171 mg/100gm and 3.242 mg/100gm, respectively.  It was concluded that the greater the percentage of quinoa in substitution the higher the nutritional value and the better general acceptance. As for general palatability, the mixtures contained 10% followed by 20% had a slight difference until the end of the experiment.

Therefore, it is recommended to utilize the quinoa seeds because of their high nutritional values in nutrition, where for children, the elderly and vegetarian people in several forms as flour in the baked goods or in a puree form added to fruits and vegetables.

Moisture transfer characteristics of dambu-nama (DN) as influenced by addition of citric acid, salt and sugar as hurdles were investigated. Four products comprising DN with 0.1% citric acid + 2% salt and 2% sugar (DNC_0.1); DN+ 0.2% citric + 2% salt + 2% sugar (DNC_0.2); DN + 0.3% citric acid +2% salt + 2% sugar (DNC_0.3) and a control DN without citric acid , salt or sugar (DNC₀) were produced and subjected to moisture sorption studies at different temperatures (30, 40, 50 and 60^oC) and relative humidities of(10-96%). Incorporation of the hurdles into dambu-nama resulted in increase in monolayer moisture contents, surface areas, net isoteric heats and entropy of sorption. The isotherms obtained were best described by the Henderson model followed by the GAB and Oswin models.  The hurdles also resulted to a J-shaped isotherm instead of the sigmoidal isotherm shape.

The herbal plant known as Tinospora crispa is reported to have many beneficial effects on health and has great potential in future to be developed as a health product either in the form of traditional medicine, food supplements or in pharmaceutical preparations. However, so far knowledge on processing procedures to produce quality standardized extracts of this plant to be used in product development has still not widely reported. Therefore, the objective of this study was to determine the optimal extraction conditions for producing a standardized T. crispa aqueos extract (STCAE) with high extraction yield and high syringin content. Experiments were conducted to determine the effects of various extraction conditions involving temperature (25–100 ° C), extraction time (0.5–6 hours) and liquid (water) to solid ratio (5: 1–25: 1 ml of solvent per g stem dry). Using optimized conditions obtained, the extract was standardized based on syringin and was further investigated on its antioxidant activity through DPPH, FRAP and TBA bioassays. Results revealed that the optimum extraction conditions were found to be 1 h extraction time and 15:1 ml g−1 liquid-to-solid ratio. For the extraction temperature, 60°C was found to be the best. STCAE was produced on the basis of the extract to contain with at least 0.4 wt% of syringin. STCAE was found to possess high antioxidant activities through DPPH, FRAP and TBA bioassays.

Color and pigment analyses are not required by the majority of olive oil marketing standards. However, it is a basic attribute that is highly associated, by most consumers, with the idea of quality. In this study, we aim at providing a fast non-invasive method for routine analysis that can be used on a large scale in the laboratories of olive oil analysis starting from pigment quantification and color range measurements. A selection of 172 virgin olive oil samples obtained in Tunisia between 2018 and 2019 were used for this purpose. Chlorophyll and carotenoid contents were analyzed using a UV spectrophotometer standard method while color range was measured using digital images taken under controlled conditions. All samples showed high significant differences in chlorophyll and carotenoid contents (p <0,01) confirming that the visual selection of the set of samples was satisfactory for this study. Chlorophyll content varied from 3,0 to 28,3 ppm for samples SM137 and SM96 respectively, while carotenoids ​​oscillated between 0,7 and 6,2 ppm for SM138 and SM100 respectively. Principal component analysis using chlorophyll and carotenoids contents along with RGB-CYMY color measurements showed a higher significant correlation P<0,05 between pigment contents and Red, Green, Blue and Yellow colors. Bivariate tests suggest that although color and pigments are correlated, color range assessment using digital imaging may represent a more sensitive method to discriminate olive oil according to cultivar, geographical origin, maturation index and year of harvest.

The present study was undertaken to develop an alternative idli from proso millet with horse gram and fenugreek seeds. Two types of wet batters (Batter A & Batter B) were prepared by soaking     the ingredients proso millet, horse gram and fenugreek separately (in the ratio by weight 7:2:1) in excess water for 8 hours at room temperature (25±2ºC). In method A, the ingredients were soaked in excess water and whereas in method B, fenugreek was soaked in buttermilk. The soaked ingredients were ground separately with adequate amount of water using a grinder and mixed with the addition of 1% salt. The resulting batter was fermented for 10 hours at room temperature. The batter was analyzed for its microbial load (Total Plate Count, Lactobacillus and Yeast and Mold) and physico-chemical properties (height rise, pH and titratable acidity) by drawing aliquots at fixed intervals. Microbial analysis revealed maximum load at 6^th hour of fermentation for TPC, LAB and Yeast growth. Suppressing activity of the organisms was seen after this stage and there was                  a sharp decline in microbial growth (LAB and Yeast). The pH and total titratable acidity ranged between 4.88-6.20 and 0.19–0.51% respectively. The nutritional analysis and sensorial acceptance of the idli formulated with both the batters were also studied. Both the idlis were found to have                   a two-fold increase in protein content and a 50% reduction in carbohydrate content when compared with the traditional rice idli. The sensory analysis was conducted with 100 untrained panelists and the results revealed that idli prepared from Batter A was preferred. A dry ready to cook idli mix was also formulated and was studied for the above said properties. The study highlights that proso millet, horse gram and fenugreek can be used as an effective alternative for preparation of idli.

Soft drinks nowadays are becoming an important part of the modern diet consumed in many communities worldwide and are available in the market virtually in the same form almost anywhere around the globe. Additives such as antioxidants and preservatives are usually added to soft drinks to increase their shelf life. Several acids such as benzoic and ascorbic acid are used in beverages to prevent oxidation and degradation of matrix.  Literature documented that combination of these preservatives in soft drinks results in benzene formation. Moreover, benzene has long been reported to inflict many public health problems. This review elucidated different health consequences such as hematological, neurological, reproductive and carcinogenic effects of exposure to benzene. Liver and kidney derangements were also reported from different epidemiological and experimental studies. Therefore, we suggest that combination of ascorbic acid and benzoic acid in beverages should be avoided by small scale and industrial manufactures. A closer monitoring of these preservatives in beverages by regulatory agencies is highly needed.