More than 27% of total phenolics were lost in blanched refiner. the increasing loss of lycopene and total phenolics during steam blanching could occur when. Keywords: Enzymatic browning, dipping, blanching, coating, preservation. Introduction. Fruit and vegetables have health benefits for consumers, due to their. Abstract. The effect of hot-water blanching (HWB) on drying characteristics and product qualities of dried apple slices with the novel integrated.
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Hardness of freeze-dried samples in 3 freeze-drying methods. There was significant difference among the porosity of samples in the three methods. The use of hot-water blanching HWB as a pretreatment is usually carried out to inactivate enzymes and remove air from intercellular space of fruits and vegetables in order to prevent off color and flavor changes during drying [ 12 — 14 ]. Jurnal Pangan dan Industri. The results of the porosity measurement were consistent with the observation results of SEM images in Figure 9which identified that the VF-FD samples had a dense structure.
Journal of Food Quality
Apparent photographs of freeze-dried samples with 3 freeze-drying methods. However, to our knowledge there are no available reports on the studies on the NIFD processing technology of apple slices pretreated with HWB.
White saffron tubers of mangga sp. Meanwhile, water content and water solubility index in the range 4. Tepung Singkong SNI PT Gramedia Pustaka Uta-ma. Article Tools Print this article. The inevitable foreign heat transmission might undermine the apparent difference of frozen temperature of apple samples caused by different mass loss. Vitamin C content of freeze-dried samples in 3 freeze-drying methods. Email this article Login required.
Firstly, the SEM images were turned into gray level and binarized by using an automatic image processing method based on the gray level difference between adjacent pixels, which was performed using Matlab code Mathworks, Inc. Subscribe to Table of Contents Alerts. Schematic of the vacuum freeze dryer used. In order to simplify the food FD processes and shorten the drying time, we proposed a novel integrated freeze-drying NIFD processing technology based on the principle of vacuum cooling and vacuum freeze dryer [ 910 ].
The materials are then transferred into freezing unit and FD unit. In every processing method, 5 SEM images were taken from the dried apple samples to analyze the pores network structure. Vacuum freeze-drying FD has been considered as one of the best methods for obtaining dehydrated foods with high quality. The reason may be inferred that the removed latent heat by mass loss water evaporation in the samples during the VF treatment came from the sensible heat for reducing samples temperature, the latent heat for forming ice crystals in the samples, the foreign heat transmitted from the plates, and the ambient chamber into the apple samples.
Keywords White saffron blanchibg antioxidant; blanching. To quantify the difference in the structure of dried samples, the porosity in the structure was determined. Higher mass loss and more temperature decrease in HWB-VF-FD were more favorable for the NIFD process by considering the requirement of the fully freezing and the eutectic temperature of fresh samples as well as the least FD time as possible.
The total color difference was used to characterize the variation of in products color during processing by applying the following equation: The specific objectives were to know the effect of temperature and blanching time on the linoleic acid ujrnal. User Username Password Remember me. The main objectives of the current study are to evaluate the effect of HWB on the drying characteristics and product qualities of apple jurhal dried with the NIFD process, including mass loss and frozen temperature of apple samples at the end of freezing treatment, freezing time, freeze-drying time, rehydration ratio RRshrinkage ratio SRVitamin C content, color, texture, and microstructure of FD apple slice.
It is well known that FD is a drying method with high production cost. During pretreating in practice, the materials especially fruits and vegetables are usually conducted in the sequence steps including selecting, washing, slicing, blanching, quickly cooling, draining residual water, and filling trays. The CFD process technology is characterized by many disadvantages including complicated process steps, large space occupation, huge equipment investment, frequent materials transferring, long drying time, and high production cost [ 14 ].
Orange sweet potato is one of many tubers as raw materials for food processing diversify. Apple samples without jurrnal pretreatment were performed with vacuum freezing treatment and freeze-drying process. Correspondence should be addressed to Hai-ou Wang ; moc.
Pengaruh Blanching terhadap Sifat Antioksidasi Sirup Kunir Putih (Curcuma Mangga Val.) – Neliti
In order to obtain a successful FD performance, the fresh raw materials were required to be fully frozen and keep frozen temperature below their eutectic temperature. Materials and Methods 2. To receive news and publication updates for Journal of Food Quality, enter your email address in the box below. User Username Password Remember me. Porosity of freeze-dried samples in 3 freeze-drying methods.
Before HWB pretreatment, cell wall and membrane were tightly bonded with each other, and the cell membrane was thick, intact, and continuous in shape and dimension. Finally, the samples were double-stained using uranyl acetate and lead citrate. Among the color parameters, expresses the brightness of sample, a higher value of means brighter color; and with decreasing value indicate red to green and yellow to blue, respectively; shows the color change compared to the original fresh samples.
Abstract The effect of hot-water blanching HWB on drying characteristics and product qualities of dried apple slices with the novel integrated freeze-drying NIFD process was investigated by comparing with 3 different FD methods.
Apple slices were pretreated with HWB and then were ujrnal transferred into the vacuum freeze dryer to perform the VF treatment and FD process. In Figure 9it can be found that the honeycomb network was formed in the tissues of all the samples.
Email the author Login required. Cross-sectional observed samples for scanning electron microscopy SEM analyses were obtained by naturally fracturing the freeze-dried samples with the aiding of instant freezing by blancning nitrogen.
The refrigeration machine also provides refrigerating output to the clod trap to condense the water vapor generated from food samples. This journal is published under the terms of the is licensed under a Creative Commons Attribution-ShareAlike 4. It can be inferred that ice melting and collapsing occurred during the FD process because of the incomplete freezing status caused by insufficient mass loss during the VF treatment. Besides, microvolume distribution of water in the apple tissue during the VF treatment can directly influence the size of ice crystal and the network pores.
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An industrial-scale FD process for most fruits and vegetables generally consists of 4 main stages, including pretreating, freezing, freeze-drying primary drying and secondary dryingand judnal.