PHYTOCHEMICAL AND MICROBIOLOGICAL ANALYSIS OF DEVELOPED FREEZE DRIED WATERMELON AND TOMATO POWDER

2021 ◽  
pp. 21-29
Keyword(s):  
Microbiological Analysis ◽  
Freeze Dried ◽  
Tomato Powder

Evaluation of physico-chemical properties of tomato powder produced by an optimized freeze drying process

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Zeyu Wu ◽  
Haiyan Wang ◽  
Li Zhang ◽  
Zhaojun Xian ◽  
Honghong Li ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Freeze Drying ◽  
Binding Capacity ◽  
Chemical Properties ◽  
Soluble Solids ◽  
Drying Process ◽  
Total Acid ◽  
Physico Chemical ◽  
Freeze Dried ◽  
Tomato Powder

Abstract In this study, the physico-chemical properties of tomato powder produced by an optimized freeze drying process (FDP) were evaluated. With the lycopene content as the dependent variable, the optimum FDP conditions (i.e., thermal cracking time of 62 s, ascorbic acid addition amount [0.13%], and particle size [Dv90] of 163 μm) were obtained through response surface methodology (RSM). The results showed that the content of lycopene in the prepared tomato powder was higher than that in two commercial products. Aldehydes were the main components among 25 kinds of aromatic substances detected in tomato powder. The values of a * and a */b *, the hydration properties including water holding capacity (WHC) and oil binding capacity (OBC), and the content of total acid, ascorbic acid, and soluble solids were improved compared to commercial spray dried and freeze dried samples. All the above results suggested that FDP was an adequate procedure for the production of high-quality tomato powder.

scholarly journals Determination of Microbial Properties of Freeze Dried Traditional Cheese

2019 ◽  
Vol 7 (4) ◽  
pp. 688
Author(s):  
Tuba Büyüksırıt Bedir ◽  
Hakan Kuleaşan
Keyword(s):  
Freeze Drying ◽  
Salt Content ◽  
Titratable Acidity ◽  
Microbiological Analysis ◽  
Effective Prevention ◽  
Freeze Dried ◽  
White Cheese ◽  
Tulum Cheese ◽  
Yeasts And Molds

The use of dried cheese in food production and food preparation sectors is becoming increasingly widespread. Dried cheese is preferred because of their longer shelf life at room temperatures, smaller packaging sizes, practical use, and their ease of homogenization in food products. Various technologies are currently being used for the drying of cheese and efforts are still being made to develop new methods. Freeze drying is a highly preferred technique for the production of dried cheese due to high quality of the final product. Instant removal of water and low process temperatures ensure an effective prevention of chemical and microbial deterioration. In this study, White, Kashar and Tulum cheeses were dried by freeze-drying method. Physicochemical analyses were carried out on the first day in order to determine the initial quality of cheese samples. The moisture and salt content were highest in White cheese, titratable acidity and fat content were highest in Tulum Cheese. Freze dried cheese samples were stored in room conditions for 6 months and changes in microbial populations such as mesophilic aerobic bacteria, yeast and moulds, lactic acid bacteria, Staphylococci spp. and coliform group bacteria were determined. The results showed that Tulum Cheese contained highest microbial counts in general. The number of bacteria was 7.71±0.10 log cfu/g in Tulum Cheese, 5.70±0.07 log cfu/g in White cheese. Total counts of yeasts and molds were 7.37±0.06 log cfu/g for Tulum cheese and 4.92±0.07 log cfu/g for Kashar Cheese. Statistical analysis was performedby using Minitab Statistical Package Program to evaluate the results of microbiological analysis on dried cheese samples.

scholarly journals Development and Quality Evaluation of Freeze-Dried Instant Green Smoothie Powder

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
S. H. B. Dilrukshi ◽  
H. P. S. Senarath
Keyword(s):  
Fruits And Vegetables ◽  
Food Product ◽  
Leafy Vegetables ◽  
Food Sources ◽  
Plate Count ◽  
Microbiological Analysis ◽  
Green Leafy Vegetables ◽  
Freeze Dried ◽  
Health Promoting ◽  
Powder Properties

Fruits and vegetables are healthy food sources which contain nutrients and phytochemicals with health-promoting properties. The production of healthy and more convenient products can be contributed to increase the consumption of fruits and vegetables. In this study, a novel, instant food product which is more nutritive was developed using locally available fruits and green leafy vegetables and the physicochemical, microbial, and sensory qualities of the product were studied. The most acceptable formula for the fresh green smoothie was 28.6% green content with 71.4% fruit content. The developed green smoothie was freeze dried to obtain an instant green smoothie powder. The instant green smoothie powder was analyzed for proximate composition: protein ( 2.67 ± 0.00 ), fat ( 1.96 ± 0.001 ), moisture ( 4.82 ± 0.003 ), ash ( 1.22 ± 0.000 ), and fiber ( 28.57 ± 0.008 ). This instant powder contained 129.5 ppm vitamin C content and higher amount of minerals such as K ( 0.98 ± 0.12   mg / g ), Ca ( 1.74 ± 0.03   mg / g ), and Fe ( 0.04 ± 0.004   mg / g ). The powder properties revealed that the powder has very good flowability ( 6.665 ± 2.354 ) according to the Carr Index and it has low cohesiveness ( 1.0713 ± 0.0264 ) according to the Hausner ratio. The solubility ( 94.71 ± 2.4253 ) of the powder complied with the SLS (668: 1984). The microbiological analysis revealed that this powder only contains 1 log CFU/ml of total plate count. This instant powder can be introduced as a more convenient and healthy choice for the consumers which has acceptable sensory properties, better microbiological stability, and very good powder properties.

Phytochemical Study and its Quantity and Quality of Fresh and Freeze-Dried Young Coconut Juice (Cocos nucifera L.)

2014 ◽  
Vol 884-885 ◽  
pp. 490-493 ◽  
Author(s):  
P. Rattanaburee ◽  
T. Amnuaikit ◽  
N. Radenahmad ◽  
J. Puripattanavong
Keyword(s):  
Cocos Nucifera ◽  
Physicochemical Analysis ◽  
Microbiological Analysis ◽  
Drying Process ◽  
Phytochemical Study ◽  
Dry Extract ◽  
Freeze Dried ◽  
Suitable Technique ◽  
Microbiological Properties

Young coconut juice (YCJ) from aromatic green dwarf variety fruit of Cocos nucifera L. (Family Arecaceae) is high valuated because of its nutritional and pharmacological properties (wound healing, anti-Alzheimer, anti aging). Due to the storage and handling problems, YCJ has been prepared in dry form by freeze-drying process in this study. The % yield of freeze-dried YCJ powder was 6.62 ± 0.28 %. Both of them (fresh and freeze-dried YCJ) were further studied on phytochemical, physical, chemical and microbiological properties. The results showed that β-sitosterol was isolated and identified by means of spectral data and their physical properties. The HPLC-parameters (linearity, repeatability, accuracy and specificity) were evaluated. The concentrations of β-sitosterol in HPLC analysis of both fresh and freeze-dried YCJ were 89.67 ± 0.01 and 31.84 ± 1.56 μg/ml, respectively. Furthermore, there was no significant (p>0.05) difference in physicochemical analysis in between both products. Therefore, the microbiological analysis of these products was within standard range of Thai community products standard (TCPS). In conclusion, Freeze-dried YCJ was observed to be the suitable technique to obtain the dry extract of young coconut juice.

Three-Dimensional Reconstruction Using Stereo Pairs from Serial Thick Sections

1977 ◽  
Vol 35 ◽  
pp. 562-563
Author(s):  
Robert Glaeser ◽  
Thomas Bauer ◽  
David Grano
Keyword(s):  
Three Dimensional ◽  
Dimensional Structure ◽  
Serial Sections ◽  
Thin Sections ◽  
3 Dimensional ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Dimensional Reconstruction ◽  
Stereo Imagery ◽  
Whole Mounts

In transmission electron microscopy, the 3-dimensional structure of an object is usually obtained in one of two ways. For objects which can be included in one specimen, as for example with elements included in freeze- dried whole mounts and examined with a high voltage microscope, stereo pairs can be obtained which exhibit the 3-D structure of the element. For objects which can not be included in one specimen, the 3-D shape is obtained by reconstruction from serial sections. However, without stereo imagery, only detail which remains constant within the thickness of the section can be used in the reconstruction; consequently, the choice is between a low resolution reconstruction using a few thick sections and a better resolution reconstruction using many thin sections, generally a tedious chore. This paper describes an approach to 3-D reconstruction which uses stereo images of serial thick sections to reconstruct an object including detail which changes within the depth of an individual thick section.

Scanning and Transmission Microscopy of Nematocyst Batteries in Epitheliomuscular Cells of Hydra

1971 ◽  
Vol 29 ◽  
pp. 410-411 ◽  
Author(s):  
Jane A. Westfall ◽  
S. Yamataka ◽  
Paul D. Enos
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Osmium Tetroxide ◽  
External Surface ◽  
Three Dimensional ◽  
Surface Structures ◽  
Transmission Microscopy ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Scanning Electron

Scanning electron microscopy (SEM) provides three dimensional details of external surface structures and supplements ultrastructural information provided by transmission electron microscopy (TEM). Animals composed of watery jellylike tissues such as hydras and other coelenterates have not been considered suitable for SEM studies because of the difficulty in preserving such organisms in a normal state. This study demonstrates 1) the successful use of SEM on such tissue, and 2) the unique arrangement of batteries of nematocysts within large epitheliomuscular cells on tentacles of Hydra littoralis.Whole specimens of Hydra were prepared for SEM (Figs. 1 and 2) by the fix, freeze-dry, coat technique of Small and Màrszalek. The specimens were fixed in osmium tetroxide and mercuric chloride, freeze-dried in vacuo on a prechilled 1 Kg brass block, and coated with gold-palladium. Tissues for TEM (Figs. 3 and 4) were fixed in glutaraldehyde followed by osmium tetroxide. Scanning micrographs were taken on a Cambridge Stereoscan Mark II A microscope at 10 KV and transmission micrographs were taken on an RCA EMU 3G microscope (Fig. 3) or on a Hitachi HU 11B microscope (Fig. 4).

Characterization of microtubules by dark-field STEM and replication

1991 ◽  
Vol 49 ◽  
pp. 152-153
Author(s):  
S.B. Andrews ◽  
R.D. Leapman ◽  
P.E. Gallant ◽  
T.S. Reese
Keyword(s):  
Protein Interactions ◽  
Low Dose ◽  
Unit Length ◽  
Dark Field ◽  
Carbon Films ◽  
Microtubule Associated Proteins ◽  
Molecular Weights ◽  
Freeze Dried ◽  
Protein Motors ◽  
Associated Proteins

As part of a study on protein interactions involved in microtubule (MT)-based transport, we used the VG HB501 field-emission STEM to obtain low-dose dark-field mass maps of isolated, taxol-stabilized MTs and correlated these micrographs with detailed stereo images from replicas of the same MTs. This approach promises to be useful for determining how protein motors interact with MTs. MTs prepared from bovine and squid brain tubulin were purified and free from microtubule-associated proteins (MAPs). These MTs (0.1-1 mg/ml tubulin) were adsorbed to 3-nm evaporated carbon films supported over Formvar nets on 600-m copper grids. Following adsorption, the grids were washed twice in buffer and then in either distilled water or in isotonic or hypotonic ammonium acetate, blotted, and plunge-frozen in ethane/propane cryogen (ca. -185 C). After cryotransfer into the STEM, specimens were freeze-dried and recooled to ca.-160 C for low-dose (<3000 e/nm2) dark-field mapping. The molecular weights per unit length of MT were determined relative to tobacco mosaic virus standards from elastic scattering intensities. Parallel grids were freeze-dried and rotary shadowed with Pt/C at 14°.

The Effects of Drying Techniques on Clay-Rich Soil Texture

1974 ◽  
Vol 32 ◽  
pp. 466-467
Author(s):  
T. G. Naymik
Keyword(s):  
Critical Point ◽  
Liquid Nitrogen ◽  
Liquid Nitrogen Temperature ◽  
Drying Methods ◽  
Air Drying ◽  
Freeze Dried ◽  
Critical Point Drying ◽  
Set Up ◽  
The Relationship ◽  
Quartz Grains

Three techniques were incorporated for drying clay-rich specimens: air-drying, freeze-drying and critical point drying. In air-drying, the specimens were set out for several days to dry or were placed in an oven (80°F) for several hours. The freeze-dried specimens were frozen by immersion in liquid nitrogen or in isopentane at near liquid nitrogen temperature and then were immediately placed in the freeze-dry vacuum chamber. The critical point specimens were molded in agar immediately after sampling. When the agar had set up the dehydration series, water-alcohol-amyl acetate-CO2 was carried out. The objectives were to compare the fabric plasmas (clays and precipitates), fabricskeletons (quartz grains) and the relationship between them for each drying technique. The three drying methods are not only applicable to the study of treated soils, but can be incorporated into all SEM clay soil studies.

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