MyMedR

Displaying all 3 publications

Abstract:

Sort:

Fulltext Application of foam-mat drying with egg white for carrageenan: drying rate and product quality aspects

Djaeni M, Prasetyaningrum A, Sasongko SB, Widayat W, Hii CL

J Food Sci Technol, 2015 Feb;52(2):1170-5.
PMID: 25694735 DOI: 10.1007/s13197-013-1081-0

Drying is a significant step in the production of carrageenan. However, current drying process still deals with too long drying time and carrageenan quality degradation. The foam mat drying is an option to speed up drying process as well as retaining carrageenan quality. In this case, the carrageenan was mixed with egg white (albumin) as foaming agent and methyl cellulose for foam stabilizer. The foam will break the carrageenan gels and creates the porous structure resulting higher surface area for water transfer. This research studied the effect of egg white and methyl cellulose on carrageenan drying at various air temperature, and thickness. As a response, the water content versus time was observed and the drying rate was estimated. Meanwhile, the carrageenan texture was verified by X-RD (X-Ray Diffraction) and TEM (Transmission Electron Microscopy). Results showed that the presence of egg white stablized by methyl cellulose can speed up drying rate as well as retaining the crystalline structure of carrageenan. The higher albumin content, the faster drying rate. However, the addition of albumin and methyl cellulose restricted not more than 30 % in the mixture for keeping carrageenan quality and purity. By adding egg white 20 % and methyl cellulose 10 %, the water diffusion and drying rate can be two fold compared with carrageenan drying without foam. The improvement can be higher at the higher temperature and thinner carrageenan sheets.
Improving Malaysian cocoa quality through the use of dehumidified air under mild drying conditions

Hii CL, Law CL, Cloke M, Sharif S

J Sci Food Agric, 2011 Jan 30;91(2):239-46.
PMID: 20872824 DOI: 10.1002/jsfa.4176

Various studies have been conducted in the past to improve the quality of Malaysian cocoa beans. However, the processing methods still remain crude and lack technological advancement. In terms of drying, no previous study has attempted to apply advanced drying technology to improve bean quality. This paper presents the first attempt to improve the quality of cocoa beans through heat pump drying using constant air (28.6 and 40.4 °C) and stepwise (step-up 30.7-43.6-56.9 °C and step-down 54.9-43.9 °C) drying profiles. Comparison was made against hot air drying at 55.9 °C.
Effects of drying on total polyphenols content and antioxidant properties of Carica papaya leaves

Yap JY, Hii CL, Ong SP, Lim KH, Abas F, Pin KY

J Sci Food Agric, 2020 May;100(7):2932-2937.
PMID: 32031257 DOI: 10.1002/jsfa.10320

BACKGROUND: Papaya is widely grown in Malaysia and normally only the fruits are consumed. Other parts of the plant such as leaves, roots, bark, peel, seeds and pulp are also known to have medicinal properties and have been used to treat various diseases. Papaya leaves also contain flavonoids, alkaloids phenolic compounds and cynogenetic compounds, and are also reported to be able to treat dengue fever.
RESULTS: Studies were carried out on drying of papaya leaves using hot air (60, 70 and 80 °C), shade and freeze drying. Effective diffusivities were estimated ranging from 2.09 × 10-12 to 2.18 × 10-12 m2 s-1 from hot air drying, which are within the order of magnitudes reported for most agricultural and food products. The activation energy to initiate drying showed a relatively low value (2.11 kJ mol-1 ) as a result of the thin leave layer that eased moisture diffusion. In terms of total polyphenols content and antioxidant activities, freeze-dried sample showed a significantly higher (P

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links