Natural colorants are important alternatives to synthetic colorants. They are considered harmless and positively affect biological activities owing to their antioxidant potential. The present study deals with the assessment of the extraction processes and the effects of pH (1.0, 3.0, and 5.0), extraction media (water and 50% ethanol) and storage condition (ambient and refrigeration) on betacyanin content, color values, as well as degradation kinetics of total betacyanins in red amaranth. Betacyanin content was more stable at higher than at lower pH. The degradation rate constant (K) was higher and the half-life (t 1/2) was lower at ambient temperature compared to refrigeration temperature. Betacyanin degradation was higher at ambient temperature (30 ± 2°C) than at refrigeration temperature (4°C). The pH, storage time, and temperature affected the stability of the color attributes. Therefore, this work suggests that water and lower temperature (4°C) could be applied to extract more betacyanins from red amaranth and betacyanins might be used as an alternative to synthetic color.

Pectin was extracted using 0.1 N HCl at 90 8C for 120 min at pH 1.5 and 2.0 from pomelo peel and characterized in this study. Influence of various concentrations of extracted pomelo peel pectin on physicochemical, bioactive compounds, color, and sensory attributes of carrot jam during storage was also studied. Pectin extracted at pH 2.0 had higher ash content, equivalent weight, and total anhydrouronic acid content than that extracted at pH 1.0. Extracted pomelo peel pectin was categorized as high-methoxyl pectin based on the degree of esterification. The b-carotene and total phenol content were increased in jam after 90 days of storage. Ascorbic acid content decreased with increasing storage period. Jam prepared using commercial pectin had higher DE values than jam prepared using pomelo peel pectin. Physico-chemical properties were influenced by pectin concentrations and storage time. Overall acceptability was similar for all samples on the basis of sensory evaluation. The results showed that pomelo peel might be used as a rich source of pectin and pomelo peel pectin could be used as an alternative to commercial pectins for carrot jam preparation. Practical applicationsPectin is one of the main ingredients for jam and jelly making. Citrus fruits are main sources of pectin. Usually pomelo peels are discarded as waste materials. However, it could be a good source of pectin. In this article, pectin was extracted from pomelo peel and its application was observed as carrot jam during storage. Therefore, it can be concluded that extraction of pectin from pomelo peel might be used as an alternative to commercial pectin for carrot jam preparation. | I N TR ODU C TI ONThe most widely cultivated citrus fruits are the following: orange, lemon, lime, mandarin, grape fruit, and pomelo. Citrus fruit pulp consists of 60-65% peels, 30-35% segment, pulp, and 0-10% seeds (Afshar & Naser, 2008). Citrus by-products are considered as rich sources of phytochemicals, pectin, and dietary fibers (Afshar & Naser, 2008). Pectin is the methylated ester of polygalacturonic acid, which contains 1,4-linked a-D-galacturonic acid residues (Mesbahi, Jamaliana, & Farahnaky, 2005).Pectin can be divided into two types based on the degree of esterification (DE): high-methoxyl pectin (DE > 50%) and low-methoxyl pectin (DE < 50%) (Mesbahi et al., 2005). The main sources for commercial pectin production are apple pomace and citrus peels (Mesbahi et al., 2005). The extracted pectin from pomelo peel could be used as ingredient in jam production. Therefore, the objectives of this study were to characterize pomelo peel pectin, as well as produce carrot jam, using various concentrations of pomelo peel pectin and compare with commercial pectin by performing nutritional quality and sensory evaluation during storage. | M A TE RI A L S A ND M E TH ODS | Sample collection and preparation of pomelo peel powderPomelo was purchased from the local market of Dinajpur, Bangladesh. The pomelos were washed carefully with tap water to remove dirt soil from the s...

Cereal industry and its derived products have a large economic and social importance worldwide. Baking industries are extensively using wheat flour to produce various baked products. Therefore, in this investigation it is intended to study and determine proximate, physicochemical, functional properties of six brand of wheat flour in Bangladesh. The entire brand had moisture contents: 9.90-12.48%, protein: 8.67-12.47%, fat: 0.893-1.387% and ash content: 0.387-0.707%. The ACI brand had the highest amount of protein of 12.47% whereas Romoni brand had highest fat of 1.387%, fiber: 0.26%, gluten content: 15.34% and water absorption index of 1.9 g/g as compared to other brands. In addition, sodium and calcium content were higher in ACI brand whereas potassium content was higher in Romoni brand. Results showed that wheat flour from all brand could be used to make various type of baked products.Bangladesh J. Sci. Ind. Res. 50(3), 181-188, 2015

Lycopene was extraction, isolation and purification using recrystallization, column chromatography, and preparative thin layer chromatography (TLC) methods as well as degradation kinetics of lycopene were studied at refrigerated temperature and room temperature for 3 wk from watermelon. Higher lycopene degradation was observed at refrigerated temperature as compared to ambient temperature throughout the storage periods. The highest amount of lycopene retained in recrystallization (101.69 μg/g) followed by column chromatography (18.20 μg/g) and preparative TLC (15.57 μg/g). Color parameters, half-life time (t ), and color retention (%R) were dependent on extraction, isolation, and purification methods and storage life. Recrystallization and preparative TLC were followed by first order reaction model. Preparative TLC exhibited higher activation energy than did the recrystallization and column chromatography. Therefore, the result shows that recrystallization method could apply to extract and purify lycopene from watermelon that would also be used as a natural colorant as well as value-added product.

The objective of this study was to standardize the formulation of honey nut drink, to assess the quality parameters like pH, brix, acidity, brix acid ratio and sensory characteristics of formulated honey nut drink under 12 days of storage at ambient temperature (32±2°C). The pH values varied from 3.5 to 3.9 during storage. The brix found in three different products ranged from 7 to 13%. The acidity possesses during the entire storage period between 0.16 to 0.32%. The brix acid ratio higher found in product 2 (59.99) and lower in product 3 (35.0) under storage. The sensory profile of three different formulation was evaluated in terms of color, flavor, taste and overall acceptability. Among the three-products formulation product 1 retained better quality followed by product 3 and product 2 considering pH, brix and acidity percentage although after increasing time of storage their value also increased. The sensory profile of product 3 found in much better score followed by the product 1 and product 2 which are significantly different (p≤0.05). In conclusion, both formulation of product 1 and product 3 could be produced in commercial purpose.