Proximate, functional and pasting properties of a new variety of sweet potato, VitAto, flour, known for its high vitamin A contents, were compared with two other commercial sweet potatoes, Bukit Naga and Okinawan, flour available in Malaysia. The recoveries of each sweet potato from milling were not significantly different at about 20% but in proximate analysis, the VitAto presented the highest protein (5.7%) and dietary fiber (14.8%) contents with more energy 399.6 kcal/100 g produced. The VitAto flour has average particle size of 132.04 μm. The pasting temperature of the VitAto flour was 65oC, with highest setback and trough viscosity values of 530.90 and 197.20 mPa.s, respectively. The flour is classified as easy flowing and stable powders. This study provides information which helps in the handling, packing and storage of sweet potato flours. It also shows that the VitAto flour has an array of functional, pasting and proximate properties that can facilitate its uses in many areas with better nutritional properties.
Guava (Psidium guajava L.) is a rich source of vitamin C (ascorbic acid) having high water
content (above 80%) which makes it extremely perishable, but storage, handling, processing
and transporting becomes difficult due to high moisture content. Therefore, guava needs
dehydration process by upholding its natural colour and minimum ascorbic acid losses. We
have carried out a comprehensive study to examine the influence of different drying treatments;
under direct sunlight, freezing, convection oven (50, 60, 70, 80 and 90°C) and microwave
oven (100, 250, 440, 600 and 1000 watts) on ascorbic acid concentration and colour quality
of guava. The mean values of ascorbic acid concentration of dried guava slices were changed
significantly (P < 0.05) as compared to fresh guava slices. The colour of guava slices became
yellowish with an increase in temperature and power of conventional and microwave ovens,
respectively. We found freeze drying as the best method for the dehydration of guava in terms
of ascorbic acid and natural colour preservation.
‘Cempedak’ (Artocarpus integer L.) is an aromatic exotic tropical fruit that can be widely found in Malaysia during season. The pulp yield and several physicochemical properties of five varietes of ‘cempedak’ (CH27, CH28, CH29, CH30 and CH33) were determined. The latter included total soluble solids, titratable acidity, pH, color, organic acids, sugars and carotenoid contents. Sensory evaluation of the five ‘cempedak’ varieties was conducted using Hedonic test, in which the assessed attributes include color, taste, texture and overall acceptability. Results indicate that CH33 yield the highest percentage (35.8%) of edible portion (fruit pulp), while CH27 shows the highest tiratable acidity (0.52%). CH30 had the lowest L* value (52.41), and highest intensity of color in terms of redness (32.45) and yellowness (65.27) values. All ‘cempedak’ varieties were highest in sucrose content (12.28-20.02 g/100 gFW) compared to fructose (5.70-6.72 g/100 gFW) and glucose (4.94-5.52 g/100 gFW), while malic acid (0.430.70%) was the highest organic acid as compared to citric acid (0.24-0.60%) and succinic acid (0.20-0.33%). All the ‘cempedak’ varieties studied have high content of α-carotene (2.30-45.27 μg/100 gFW), followed by β-carotene (2.30-12.23 μg/100 gFW), with CH28 having the highest content. From the five varieties of ‘cempedak’ fruit examined, it was found that CH28 ranked the highest in terms of sensory properties, namely taste, texture and overall acceptability.
The present study was aimed at assessing the effect of solvents on the yield and the color properties of amaranth extract. Two species of amaranth namely Amaranthus gangeticus and Amaranthus blitum were extracted with water, methanol and ethanol. Seven parameters like betacyanin content, total soluble solids, lightness (L*), redness (a*), yellowness (b*), hue angle (h*) and chroma (c*) were analyzed to assess extraction efficiency. Correlation analysis was carried out to assess the linear association among the analytical variables. Principal component analysis was used to establish the relationships between the different analytical variables and to detect the most important factors of variability. Among the two varieties, Amaranthus gangeticus extract contained about two and half time more betacyanin with half of total soluble solids compared to Amaranthus blitum. Water is the best as solvent for extracting betacyanin from Amaranthus gangeticus and ethanol in case of Amaranthus blitum. Among the analytical parameters, a* and c* were perfectly correlated. Three principal components were found among the seven analytical variables accounting 88% of total variability. The first principal components mostly reflected the redness (a*), whereas the second principal components reflected the betacyanin content, total soluble solids and lightness (L* value).
This study was aimed at investigating the effects of formulation on flowability of selected
herbal powders which include Labisia pumila, Ortosiphon stamineus, Eurycoma longifolia
and Andrographis paniculata using compendial methods and a recently available powder
flow analyser. The material properties such as moisture content, particles sizes, tap and bulk
densities of the pure herbal powders and the formulated powders were measured to determine
Carr index and Hausner ratio which were indices of the compendial methods. Cohesion
index and caking strength were used as basis of flowability indicator using the powder flow
analyser. The flowability of the herbal powders were improved when they were formulated into
beverages mix by mixing each herbal powders with other ingredients like sugar and nondairy
creamer before analyzed using both the compendial methods and powder flow analyser. Both
methods of flowability measurements adopted in this work complemented each other in the
understanding and characterization of powder flowability.