Open Access Original Research Article

The Optimization of Production of Instant Pounded Yam Flour Using Cultivars of White Yam (Dioscorea rotundata)

Olusola Fatimah Olagunju-Yusuf, Abdul-Razak Adebowale, Olajide Sobukola, Lateef Sanni

Asian Food Science Journal, Page 1-9
DOI: 10.9734/afsj/2019/v13i430113

Background and Objective: Instant pounded yam dough obtained from instant pounded yam flour (IPYF), is an emerging alternative to pounding boiled yams. IPYF dough that possesses similar organoleptic properties with conventional pounded yam (CPY) is of high demand in the West Africa market. The objective of this study was to produce IPYF dough of similar qualities to the CPY through optimization technique in other to enhance its marketability value.

Methodology: The study optimized IPYF samples obtained from three white yams (Dioscorea rotundata) cultivars (Efuhu, Dariboko and Aro) that were pre-treated (using blanching and steam method) and dried (using cabinet and oven driers). General factorial optimization design was utilized using pasting properties response of IPYF samples. Hedonic and Degree of difference sensory evaluation were conducted on the selected optimized IPYF and CPY samples using nine and seven points scales respectively.

Result: The selected optimized sample was Dariboko pre-treated with steam and dried using cabinet drier with 0.63 desirability value. A mean score of 7.4:7.5, 6.8:8.5, 7.2:8.5, 7.3:8.5, 6.0:8.5, 7.3:8.5, 7.2:8.5, 6.8:8.5 and 7.4:7.5 was obtained correspondingly for cohesiveness, smoothness, springiness, adhesiveness, hardness, stretch ability, taste, mouth feel, aroma and overall acceptability for the optimized IPYF sample and CPY. Scores for these attributes indicated that the optimized IPYF sample was acceptable. The degree of difference test showed that CPY was not significantly different from optimized sample in terms of smoothness, stretch ability, adhesiveness and mouth feel.

Conclusion: This demonstrates that this sample can easily pass as pounded yam has it possess important similarities with conventional pounded yam.

Open Access Original Research Article

Methyl Red Indicator on Smart Packaging as a Freshness Sensor for Tilapia Fillets

Kinanthi Ayu Sariningsih, Iis Rostini, Kiki Haetami

Asian Food Science Journal, Page 1-9
DOI: 10.9734/afsj/2019/v13i430114

This research aims to analyze the response of methyl red indicator film sensor label color changes on smart packaging in detecting the freshness of tilapia fillets over a shelf life of 10 hours at room temperature (± 25ºC). This research uses a comparative descriptive method. The parameters observed were pH values, total plate count (TPC) and total volatile base nitrogen (TVBN). The results of this research indicate that the response of the film label consists of several concentrations of methyl red namely control (0%); 0.05%; 0.5% and 1%. The best results from film sensor label response is 0.05% Methyl red concentration in detecting the freshness of tilapia fillets and showed the most rapid response to changing the color of the label at the observation of the 7th hours during storage of 10 hours with 8 times the observation time. The freshness of tilapia fillets has decreased quality with changes in pH that tend to fluctuate ie the pH has decreased and then rose again as the color changes are indicated by the film label from yellow to reddish-orange. Total volatile base nitrogen (TVBN) and total plate count (TPC) during the observation showed a trend towards the same graph results, namely, the longer shelf life will increase the decrease in freshness quality of tilapia fillets with marked decay. Therefore, the freshness level of tilapia fillets can be determined by the smart packaging sensor methyl red indicator label at room temperature storage (± 25ºC).

Open Access Original Research Article

Effect of Processing Methods on the Physicochemical, Antinutrient and Pasting Properties of Three Commonly Consumed Soup Thickeners in Nigeria

J. Eke-Ejiofor, C. U. Awajiogak

Asian Food Science Journal, Page 1-16
DOI: 10.9734/afsj/2019/v13i430115

The effect of processing methods on the physicochemical, functional, anti-nutrient factors and pasting properties of Mucuna sloanei (ukpo), Brachystegia eurycoma (achi) and Daterium microcarpum (ofor) were assessed using standard methods. Flour from these seeds were produced after boiling and soaking at different time intervals.  The moisture and ash contents of the three soup thickeners ranged between 5.58- 8.92% and 1.14-5.59% with sample B1 (achi boiled for 15 min) and C4 (ofor soaked for 48 h) having the lowest while sample B2 (achi boiled for 30 min) and C1 (ofor boiled for 15 min) having the highest. Crude Fat and fibre contents ranged from 2.90-10.95% and 1.30-14.39% with samples C1 and A1 (ukpo boiled for 15 min) as the highest respectively. Crude protein and carbohydrate contents of soup thickeners ranged between 9.19 -21.31% and 45.01-71.38% with samples A3 (ukpo soaked for 24 h) and B4 (achi soaked for 48 h) as the highest. Sugar and starch contents ranged from 2.61-5.04% and from 69.00-74.27% respectively with sample C4 and A4 (ukpo soaked for 48 h) as the lowest and sample A3 and B3 (Achi soaked for 24 h) as the highest. Amylose content increased with boiling and decreased with soaking which was the reverse amylopectin. Functional properties showed bulk density and dispersibility to range between 0.56-0.76 g/ml and 32.50-48-00% with sample B3 (achi soaked for 24 h) as highest in both cases. Solubility and swelling power ranged from 32.56-107.51% and from 4.61-8.72 g/g with sample A2 (ukpo boiled for 30 min) and A1 having the highest respectively. Foam capacity ranged from 2.50-29.50% with sample C2 (ofor soaked for 48 h) having the lowest and sample A1 having the highest, while the least gelation concentration of the three soup thickeners recorded 2.00% for all the treatments. Water absorption capacity ranged between 0.67-10.46 ml/g with B1 having the lowest and sample C2 having the highest. Antinutritional factors showed that phytate recorded 0.01 g/kg for all the treatments, tannin ranged from 2.22-40.71 mg/kg, oxalate between 3.40-7.90mg/100g and saponin between 2.60-9.18% with different treatments affecting the antinutrients. Free fatty acid, peroxide value, saponification and acid values increased with an increase in treatment time while iodine value decreased as processing time increased. Pasting result showed that treatment and time affected pasting properties with the highest values as peak viscosity 16429RVU, trough viscosity 9231RVU, breakdown 7858RVU, final viscosity 19977RVU and set back viscosity 13004RVU respectively. Peak time and pasting temperature ranged between 1.60-6.10 min and between 50.25-76.18°C for the different treatments. This study shows the need for appropriate treatment and time combination for better nutrient availability and detoxification of these seeds as soup thickeners.

Open Access Original Research Article

Effect of Roasting Temperature and Duration on the Quality of Oil from Walnut (Plukenetia conophorum) Using Response Surface Methodology

Raji, Fatima A., Akinoso Rahman

Asian Food Science Journal, Page 1-12
DOI: 10.9734/afsj/2019/v13i430116

This study investigated the effect of heat treatment and duration on yield and qualities of Walnut (Plukenetia conophorum) oil. The experimental design was carried out using the central composite rotatable design (CCRD) of response surface methodology with a total of thirteen experimental runs. The process variables and their ranges were roasting temperature 87.57ºC to 172.43ºC and roasting duration 10 min to 46.21 min. Oil from each experimental run was extracted using Piteba screw oil expeller. The expressed oil yield was determined and the results revealed that the oil yield ranged from 33.87% to 30.67% for the maximum and minimum values which were achieved at temperatures and duration of 172.43% at 25 min and 87.57ºC at 25 min respectively. Optimum process condition was achieved at roasting temperature and duration of 160ºC and 40 min with two possible solutions of 0.82 desirability which gave oil yield (33.50%); peroxide value (7.8 MeqO2/g); colour (13.69 mg/L); free fatty acid (1.46%) and iodine value (136.82 mmol/100 g). The low free fatty acid and peroxide values in walnut oil is an indication of its overall quality thus its suitability as an alternative oil to supplement existing edible oils.

Open Access Original Research Article

Nutritional Profile and Organoleptic Qualities of Milk Chocolate Incorporated with Different Spices

S. O. Aroyeun, A. F. Okunade, A. O. Obatoye, M. A. Olalekan Adeniran

Asian Food Science Journal, Page 1-8
DOI: 10.9734/afsj/2019/v13i430117

An innovative spicy chocolate was developed in this study by partial replacement of cocoa nibs with different selected spice powders of: Ginger (G11), Garlic (G12), Clove (C13), Cinnamon, (C14), Turmeric (T15), Aframomum danielli (A16), Aframomum melegueta (A17), Thyme (T18), Black Pepper (B19) and Clappertonia (C20). Milk chocolate without spices (C10) served as Control. The proximate compositions were carried out using standard methods. The Total Calorific values (TCV) was determined using the Atwater factors (physiological fuel values) of 4kcal, 4kcal and 9kcal per gram of carbohydrate, protein and fat respectively. The sensory evaluation was carried out by panel of tasters consisting of 13 males and 18 female staff of the Cocoa Research Institute of Nigeria who were used to consuming chocolates. The result showed significant differences in the proximate chemical compositions of the chocolates (p<0.05). Apart from black pepper with a An significantly lower protein and ash contents when compared to the control chocolate, all the other spices significantly caused an increase in percentage protein and ash  in  the control milk chocolate. The trend of protein increase is T18 > G11 > T15 > C20 =A17 > A16 > C14 > C13 > G12 > C10 > B19 > respectively. The range of values obtained for the proximate compositions were (%)The Total Calorific Value (TCV) also showed significant differences among all the samples at p<0.05 with the TCV of the control chocolate being the highest. The addition of spices contributed to acceptable tastes, aroma, flavor and general acceptability of milk chocolates. In Conclusion, this study showed that the incorporation of Spices in chocolate increased the protein and ash content of milk chocolate, the organoleptic acceptance while reducing the TCV values This is a desirable findings in view of the fear of high calorific values of Milk Chocolate which may predispose consumers to Obesity when large quantities.