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Food Processing - Science topic

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Questions related to Food Processing
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I am interested in doing my research thesis on ice cream, but I am not sure of the exact process, which takes place at both large scale and small scale. Can you please tell me the process and the temperature which is followed on a standard basis?
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I would be profoundly interested in the search for NON-DAIRY 'ice cream' or confection or dessert.
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Spectral imaging and NIR spectroscopy.
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Try KU Leuven in Belgium for NIR specroscopy. It is headed by Bart Nicolai, one of the top specroscopist of our time. For hyperspectral and multispectral imaging, you can try South China University of Technology under leadership of Prof. Zeng Xin An (Andy). More on hyperspectral and multispectral imaging you can try the Department of Agricultural and Food Engineering at the University College Dublin, in Ireland, headed by Da Wen Sun.
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What are the best methods to dry Spirulina?
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Dear Prof Ashraf
Maybe you can use vacuum dryer. With this method, you can drying with lower temperature so the quality product is more stable
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Tomatine and Glucosinolates are claimed to be used as pestcide and cancer drug ingredients. However, I couldn't find info in terms of their market value such as market demand, and $ value. Any clue? Thanks.
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Neilson et al (2013) discuss the social costs
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Indonesia is a country known for its coffee quality, especially specialty coffee. Kopi Luwak (Luwak Coffee), Mandheling Coffee, Sumatra Coffee, and Bali Kintamani Coffe are good examples of Indonesian specialty coffees. As we know, there are two main ways for coffee processing: dry and wet. In regards to that, I got a project for processing coffee with several fermenter/fermentor (or starter) agents for wet-processing. Some of the fermenters I want to use are Lactobacillus sp., Aspergillus sp., etc. The problem is, I need your suggestion for the other types of starters that can be used in this project. Moreover, it's preferable if that starter has been used for 'local wisdom' based coffee-processing in your area. I plan to use GC-O (Gas Chromatography-Olfactometry) and Cup-Testing (a sensory evaluation method for coffee).
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Hello! I think you should first diagnose coffee production systems in the area.
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I have plans on constructing a wireless sensor that would sense the quality changes like aroma, taste of packed food products. It'd be great if someone could help me with the approach.
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Though , I am not sure about the offshelf(commercial) available wireless aroma/taste sensors, We can design and develop wireless sensing system by interfacing the sensors(aroma,.....chemical sensors,....) with XBee radio module for wireless operations. The conditioning circuit can transmit the sensed data in ADC form. The collected (sensed) data can be anayzed for detecting appropriate color, smells,..etc.,
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What is the difference between an instron machine and a texture analyzer when it comes to measuring the mechanical properties of foods?
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Instron is a company that makes materials testing instruments in sizes/ capacities from very small to quite large (The largest ones are capable of ripping apart/ compressing iron bars, concrete slabs, etc). Many institutions/ companies use one of their smaller models to test the material properties of foods. A texture analyzer is an instrument designed specifically to test the textural properties of foods. From a practical standpoint, as long as the probes/fittings are comparable, the load cells have the same (or similar) sensitivities and capacities, and one uses the same procedure (specifically setting the probe/ crossarm speeds, deflection or maximum force, and pauses (if any) to the same values) you should see no difference in material properties measured by either.
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I'm interested in the solubility profile of commercial chitin and chitosan (Sigma) as well as the % degree of deacetylation of commercial chitosan (Sigma).
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Dear Francisco,
there are many journals dealing with chitin and chitosan preparation such as :
Int J Bio Macromol
Process Biochemistry
Polymer
Biopolymer
Carbohydrate Polymer
Carbohydrate Research
J of Apllied Polymer Science
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bha
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The researcher can set each entry point as a Critical Point in the HACCP document flow with a provision of identifying the hazard (biological, physical, chemical and allergen)
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Other than microbial analysis what are the parameters that can be used to judge the edibility of a product?
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The edibility of food other than microbial analysis is its texture, test and smell. If the texture is such that it can not be ground by teeth or elastic in nature then it is described as non edible. Same way the taste and smell should be within the threshold limit to human sensory organ perception.
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Can anyone tell me if my formula is correct?
I weighed the sample of meat (5 g +- 0.1) than was homogenate with 10 mL of TCA/DTPA. After centrifugation and filtration 5 mL of the liquid extracted was mixed with 2.5 mL of TBA solution. Then the solution was heated at 95°C and after cooling Abs was recorded.
A calibration curve was plotted with 1,1,3,3-tetraethoxypropane (TEP) and the slope was recorded.
To calculate mg MDA in Kg of fresh meat I used that formula:
(Abs sample*Volume extraction*Volume dilution)/(slope*weigh of sample)
That formula with numbers becomes:
(Abs sample*10*1.5)/(0.23*weigh of sample)
where 10 is the 10 mL of TCA/DTPA and 1.5 is the dilution from 5 mL of extracted sample plus 2.5 of TBA solution (5+2.5=7.5 mL; 7.5/5= 1.5)
where volumes are in mL and the weigh of sample is in grams.
Is that correct?
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Thank you Dr. Popova, your answer helped me to understand where I made the error in my formula.
My standard curve is in micromolar (uM), so I corrected my formula in that way:
mg of MDA in Kg of meat = (Absorbance of sample * PM of MDA * Volume of extraction * Dilution of extract added to TBA) / (weight of sample * slope of standard curve * 1000)
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Effect of protein concentration as carrier agent on physio chemical properties of spray dried powder
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Spray-drying is an effective, efficient means of producing peptide/protein-loaded powders suitable for pulmonary delivery. In addition, fine powders of proteins have application in other delivery systems (e.g., implantable pumps). If the correct formulation and spray-drying conditions can be identified, then a product can be obtained with a high yield and having a large fine-particle dose. Spray-drying is therefore a realistic alternative to the widespread practice of air-jet milling used to produce powders of low molecular-weight actives for inhalation. Indeed, air-jet milling should probably be avoided with peptides or proteins, because of possible problems of physical instability and inactivation. Apart from these considerations, spray-drying is also a suitable technique for embedding sensitive peptides or proteins in stabilizing excipients (“carriers”) such as disaccharides or amino acids.
In a study, the efficiency of drying carrier, whey protein isolate (WPI) was evaluated during spray-drying of honey. No powder was recovered when pure honey was spray-dried. Honey powders were successfully obtained (powder recovery >50%) by adding WPI alone at a ratio of Honey:WPI ratio of 70:30. The mechanisms of such a significant effect of WPI on spray-drying of honey are attributed to the preferential migration of protein to the droplet/air interface and the limited inward movement of protein during moisture evaporation, in conjunction with excellent skin-forming properties of protein upon drying. Powders' moisture content, water activity, and hygroscopicity were negligibly influenced by carriers.
Other carrier agents such as maltodextrins, gum Arabic, waxy starch, and microcrystalline cellulose, when introduced into the feed solution, influence the properties and stability of the powder. Crystalline and amorphous forms of the same material powder show differences in particle size, particle shape, bulk density, physicochemical properties, chemical stability, water solubility, hygroscopicity, flow properties and compatibility.
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A food production facility deep fries chicken products coated with a milk, wheat and soy batter and then uses the same oil to cook other products containing no allergens. My understanding is that the hot oil renders the allergens into non proteins and therefore nonallergenic. Has there been anyone known to have an allergic response to food declared to be nonallergenic after being cooked in oil previously used to cook allergen containing food? Can anyone point to a scientific research document?
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I've listed a couple relevant papers below. In general, the consensus seems to be that thermal denaturation can reduce/ eliminate the activity of some allergens, and the degree of this effect seems to be related to the structural properties of the given allergen and how they interact with antibodies in the human body. In the specific example you give, I'd be particularly concerned about the wheat and the soya, as both contain storage proteins which tend to be quite thermostable due to their numerous disulphide bridges.
Review papers:
Davis, P. J. and Williams, S. C. (1998), Protein modification by thermal processing. Allergy, 53: 102–105. doi: 10.1111/j.1398-9995.1998.tb04975.x
Mills, E. N. C., Sancho, A. I., Rigby, N. M., Jenkins, J. A. and Mackie, A. R. (2009), Impact of food processing on the structural and allergenic properties of food allergens. Mol. Nutr. Food Res., 53: 963–969. doi: 10.1002/mnfr.200800236
Research papers:
Rumbo M, Chirdo FG, Fossati CA & Añón MC. 2001. Analysis of the Effects of Heat Treatment on Gliadin Immunochemical Quantification Using a Panel of Anti-Prolamin Antibodies. J Agric Food Chem 49(12):5719-5726.
Plumb GW, Mills ENC, Tatton MJ, D'Ursel CCM, Lambert N & Morgan MRA. 1994. Effect of Thermal and Proteolytic Processing on Glycinin, the 11s Globulin of Soy (Glycine Max): A Study Utilizing Monoclonal and Polyclonal Antibodies. J Agric Food Chem 42(3):834-840.
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As I'm going to do a project on ozone treatment of mushrooms, I would like to know about its effects.
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Please find the following link it will be helpful
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Sabouraud Dextrose Agar (SDA) has been suggested as a medium that can grow yeast cultures. I don't know if it can be as simple as using SDA prepared petri dishes, adding samples of honey, and then incubating and watching for culture growth.
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If you want to count only saccharomyces cerivisae counts, than SDA is not a good choice since other yeasts will grow as well. A good indication could be to use the difference between CFU counts of SDA and SDA with cycloheximide. Saccaromyces normally doesn't grow in the presence of cycloheximide whereas wild yeast will. other media could be differential schwart'z medium
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Dear Bandaru,
Mushroom spoilage mechanism including dehydration, bacterial growing and enzymatic browning.
Respiration rate in cut or sliced mushroom is growing, this mushrooms have high capability to the water loss, enzymatic browning and microbial spoilage.
Bacterial that case bacterial spoilage in mushrooms attack cell wall fibers and accelerate enzymatic browning.
I think Ways you can use to increase shelf life of mushrooms:
1-chilling the mushrooms from harvest to cooking
2- Using of antimicrobial agent (for example ozonized water, chlorine, chlorine dioxide, citric acid etc.)
3- Using anti browning agent (for example citric acid or other poly-hydroxyl acids, reducing agent(ascorbic acid) or chelating agent).
4-Using MAP (Modify Atmosphere packaging) or EMAP (Equilibrium Modify Atmosphere packaging).
5- Using new technologies such as irradiation or High Pressure Processing (HPP).
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For my manuscript, I would like to produce a stable product from ginger. Salabat is a common beverage in the Philippines and I am conducting an experiment on how to make a product that is readily drinkable after the addition of hot water.
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You may try to make ginger-sugar solution, and then evaporate to crystalize them.
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For academic purpose I want to know more on texture characteristics, its improvement methods, packaging techniques and preservation methods of mushroom.
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Try Modified Atmosphere Packaging, it works very well.
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I am currently researching on dry noodles from non-wheat ingredients, from sweet potato. I'm having a problem that the noodles turn to brown color. I've added CMC and eggs to improve their texture. What materials should I order additionally, so that the dried noodles product still has a color that is interesting?
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I am attaching the second paper.
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Any information whether any starch like potato or tapioca, which is usually added to processed fish can hinder the detection of fish allergen? Is there any specific reaction between allergen with the starch?
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The coating of feed ingredients with either starch of fat helps minimize nutrient losses during processing of the product. Therefore, if you are unable to detect any substance in an analysis, then it could possibly be a factor.
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I want use 0/5% and 1% cysteine, but in room temperature cysteine don’t dissolve completely in water.
Can I use heat to accelerate cysteine dissolving in water?
Heat doesn't reduce cysteine reducing properties, does it?
Which condition causes cysteine off odor? How can I reduce cysteine off odor ?
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Try mild acids to make acidic conditions as the solubility of cysteine increases in the acidic pH.
Add Dil. HCL dropwise.
Here is the refernce:
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I am trying to separate oil from fish surimi wash water (waste water).
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It is very hard to separate oil from surimi wash water. However, since the property of this liquid is kind of similar to Milk, you can use the same method which is being used in dairy industry. I know some researchers and privet sectors used this method to separate the oil from protein hydrolysates solution and surimi wash water. They could separate 95% of the oil in the liquid.
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maybe I can add the answer, the total soluble solid or fiber content can make differences with waste index
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Minimally processed fruits and vegetables are Ready-to-cook and Ready-to-eat materials which undergoes minimal primary operations like, cleaning, cutting, trimming, de-seeding , packaging etc. which are to be stored in cool environment.
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The prospect of commercializing minimally processed fruits and vegetables in developing differ with the ease it is being adopted in developed countries as most of the develop countries are located in low temperature zone have good quality power supply. In contrast as developing countries located in higher temperature zone (tropical ) this higher temperature will encourage microbial growth, that such products are required to be stored at lower temperature in absence of it the produce may spoil soon. Hence we can use the technology in metro in a limited manner.
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Food samples are preserved for microbiological analysis by operators for public health to understand an outbreak. There should be a standard operating procedure around this process of collecting, preserving, and maintaining the library for public health inspection, audits for system verification, and finally removal in the event of an outbreak.
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You should look up standard analysis  documents/ standard such as British Pharmacopoeia    https://www.pharmacopoeia.com/  , some older version is downloadable  
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I measured L*, a* and b* with a tristimulus colorimeter. Then, calculated the total color difference. But what is the real implication of this index?
I read in an article, that Total color difference higher than 2 indicates noticeable visual changes in color. However, it was a citation of a book which I don't have acces.
(F.J. Francis, F.M. Clydesdate. Food colorimetry: theory and applications. The AVI Publishing Co., Inc, Westport, CT (1975))
Can someone confirm this information to me? Or explain more about this index.
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Total color difference indicated the changes of normalized L*, a* and b*. For better results, you can compare images at MATLAB using Image Processing Toolbox. See
León, K., Mery, D., Pedreschi, F., & León, J. (2006). Color measurement in L∗a∗b∗ units from RGB digital images. Food Research International, 39 (10), 1084-1091.
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Preprocessing methods in NIR spectroscopy.
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My favorite: Beebe KR, Pell RJ, Seasholtz MB. Chemometrics: A Practical Guide. 1st ed. Wiley-Interscience; 1998.
Pre-processing methods can have their pitfalls, though, even methods that you might think can only help:
I think if you are going to use a powerful multivariate technique downstream (i.e. PLS), you are often better off feeding it the raw data.
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Can we do vacuum packaging for mushrooms? how do we determine a product is suitable for vacuum packaging or not?
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I would like to know does irradiation develop rancidity in colostrum powder.
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there may not be the problem of rancidity. the problem can be protein denaturation and immunoglobulins absorption due to irradiation treatment. please refer to this article www.ncbi.nlm.nih.gov/pubmed/18024765
 
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When mushrooms are packed, within a few days a liquid oozes out with a bad odour. How can I prevent this?
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Mushroom is mostly preserved by iQF and best method is to use cryogenic freezing definitely the process is expensive.
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I would like to know how it works and what are all the changes it would make to the food material taken for cooking. Also what are all the benefits?
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Multispectral\hyperspectral imaging laboratory.
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I want to find a university lab for doing my project in this filed and provide a fellowship.
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I would like to inoculate some bacteria in marinated fish and then I will treat it with high pressure. During my storage period I also would like to do sensory assessment. But I'm confused how to perform a sensory analysis. It is impossible in inoculated samples. Should I do sensory evaluation in control or it will not be a correct comparison?
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Why is it impossible to carry out sensory analysis on inoculated fish? What is the nature of the marinade?
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I don't have access to extrusion, drum drying or spray drying equipment.
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One simple method is to first gelatinize the starch and then freeze dry the samples. It will take a lot of time (since the freeze drying is slow and only a small amount can be dryed at the same time), but it works.
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Does any article explain the relationship between hysteresis area and viscoelastic properties of food materials?
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Well, hysteresis loop is the area under the curve or it represents the upward and downward movement od shear stress vs shear rate rheolograms and can predict texture degradation. You can consult my one paper on egg rheology where I showed hysteresis. Viscoelasticity is on the other hand material behavior and show how much solid-like or liquid-like property in terms of elastic and viscous modulus. For a perfect viscoelastic fluid both could be the same and if G' exceeds G'' then the solid-like property dominates. I have many papers you can find in research gate.
It is my pleasure to guide you if you do need more info.
Good luck.
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I want to know how it's possible to produce fluid gels without a rheometer, or is possible to produced by magnetic stirrer in steady shear and on a hot plate? Are there any references about it?
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It depends on the kind of used materils
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We are trying to determine the physical characteristics of cooked idli.
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For foamed batter density, just fill a cup of even volume and level off the top with a knife before weighing. Check the cup volume by filling to the top with water at 20 C and weighing, subtracting the weight of the empty cup. Weigh to at least 1 decimal place.
To measure unaerated batter density, centrifuge idli batters in a low speed swing-out centrifuge in paired tubes, marking the containers on the side with a line showing the height of foamed batter after filling, and weighing the tube+batter before spinning.
After spinning for 30 min between 3000-5000 g draw a line carefully on the side of the tube for the level of the batter after foam is broken. Tip out the liquid and measure its weight. Draw another line for the level of the pellet. Weigh the tube + pellet. Remove pellet, wash and dry the tube, weighing the tube. Using water at 20 C, fill the tube to each line carefully, noting the weight at each line. They represent the volume of the pellet, the liquid fraction, and the gas volume in idli batter. Replicate tubes give you replicate measures.
From the weights and the volumes at each step you can calculate the gas volume fraction, liquid volume fraction and density , and solids volume and density in the batter.
I have measured idli cooked volume by seed displacement method. Method reference Griswold, R. (1962). Evaluating food by objective methods Experimental study of foods (pp. 540-541). Boston, U.S.: Houghton MiZin Co.
Weigh idlis individually on a sensitive balance (at least 1 decimal place).
Take a large container with an even lip at the top, enough to fill around 0.4 kg seed. Weight the empty container. Fill with water at 20 C to determine container volume.
Dry container, then overfill with small seeds (poppy or mustard). Tap gently to settle, level off the top evenly with a ruler and weigh. Repeat several time to get a reproducible baseline to calculate the relationship between seed weight and seed volume.
Take out a third of the seeds, place in an idli, and refill with seeds to the top, tap and level. The idli must be completely covered. Then carefully remove idli, brushing all seeds back into container, and reweigh container. Repeat to get an idea of idli volume reproducibility.
The idli density can be calculated from idli weight divided by the seed volume displaced by the idli.
You can weigh more than one idli each time, but for scientific publication ans tatistical analysis, each should be weighed separately, with replication, to determine between-idli variability. My microwave idli have about 6-8% standard deviation in volume for a 12 idli batch. Steamed idlis may be less variable.
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In comparison with other modern and new processes, food irradiation seems to be relatively well studied. However, application in Germany and other EU countries seems to be very limited. The EU positive list has not been enlarged since many years (just herbs and spices) as different stakeholders didn't agree if there is a “technological need” for this treatment. If there is interest in understanding the reasons, I plan data collection and publication.
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Most probably the fear of irradiation. Still people are cautious about the aftermath of IR treatment. As a Food Technologist, I also do not have clear understanding about the fate of IR into a food system. Although there is no report on health issue but it needs further confirmation or more study on health issue. The process is suitable for spices, potato and onion.
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We are trying to grind the palm jaggery to make palmgur but the gur sticks to the periphery of the equipment. Are there any possible solutions to this problem?
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if you can dry the gur the problem will be less or you can put thin layer of oils that could reduce stickiness somewhat. Third option, freeze dry it and grind it so there will be minimum stickiness.
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Can the foodborne pathogen TT be found in dried ready to eat snackfood (beef marinated with herbs) that's been left at ambient temperature without further processing?
Not able to explain which food pathogens can live in low water activity.
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Very good book chapter Mr Ahmed
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I am doing research to improve the shelf life of a rice cracker. It currently has a shelf life of 6 months. So what can I do to improve it. Where can I start?
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you can try using a vacuum packaging with thicker plastic. Has it been checked how the water content of the product? oil content also affect the shelf life because it can cause rancidity
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The medicinal value of spices is as a result of their phytochemical content. Hence, there is need to evaluate the phytochemical constituent of the spices using the most suitable method.
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Most of total phenolics are heat resistant up to 50 c / 24 hr
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I'm looking for legislation talking about instant pudding powder. Except Egyptian standard N0 1415/2007, I did not find anything about it.
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Hello Esther,
One of the leading US instant pudding manufacturers is Kraft Foods, which makes the Jello brand. Writing to such manufacturers may direct you to the standards and legislation you want.
Additionally, write to or check the websites of the US Food and Drug Administration and the European equivalents.
Also, the book "Salt, Sugar, Fat" by Michael Moss gives some good insight into how natural products have been radically changed by using chemicals to aid in faster or cheaper processing, and included an example about emulsifiers being used to change the time to make products from hours to just minutes! In the book, he speaks of other leading US manufacturers as well as additive suppliers - many of whom may have information that can help you.
Finally, I wonder if you would find it useful to research lobbying or consumer advocate efforts related to your area of interest. I believe many calls for change from "tinkering" with product chemistry back to natural food chemistry come from nutritionists, dieticians, and even home economics advocates. This last group was also mentioned in Michael Moss' book, which I pointed out above.
Good luck finding your information.
Regards,
Marcia
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What are the best mathematical laws for calculation of the viscosity of foods?
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There are plenty of literature on the issue. Well it depends upon how you are treating your data or the instrument you are using. For simplicity, if there is no suspended particles (filtered juice) Power law is the best. If there is pulp, try HB model. If you are using oscillatory rheology then try to match Cox-Merz rule.
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Or provide the properties of apple in the book : Choi Y, Okos MR. Thermal properties of liquid foods review. In: Okos MR, editor. Physical and Chemical Properties of Food, St Joseph, MI: American Society of Agricultural Engineers, 1986
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You may check these and the related cross references:
Diffusivity of CO2 and Water Vapors in `Gala' and `Granny Smith' Apples
Theophanes Solomos and
John C. Bouwkamp
+ Author Affiliations
Dept. of Horticulture and Landscape Architecture, Univ. of Maryland, College Park, MD 20742-5611
[HortScience August 1996 vol. 31 no. 4 590 ]
Abstract
Previous observations have shown that the diffusivity of water vapors is much larger than the value that is predicted theoretically from the magnitude of the diffusion coefficient of CO2, C2H4, or both. This has been ascribed to the ability of water to diffuse through the cuticle and to the transport of water via the capillaries of cellulase micorfibrels to the surface of the lenticels, where it evaporates. We measured the diffusivity of CO2 in `Gala' and `Granny Smith' apples. The former are more permeable to CO2 than the latter cultivar, in particular after prolonged storage at 2°C. The diffusivity of H2O was 10- to 20-fold larger than that of CO2. Furthermore, the ratio of D(H2O)/D(CO2) was similar for both cultivars. Infiltration of dyes and gas flow through apples submerged in water show that in `Gala' apples, the number of open lenticels is larger than in `Granny Smith'. Thus, the data indicate that lenticels are the main avenue of gas exchange in apples.
97
POJ 3(3):97-102 (2010)
ISSN:1836-3644
Drying of apple slices (var. Golab) and effect on moisture diffusivity and activation energy
*E. Meisami-asl, S. Rafiee, A. Keyhani and A. Tabatabaeefar
Department of Agricultural Machinery, Faculty of Bio-Systems Engineering, College of Agricultural and Natural Resource, University of Tehran, Karaj, Iran
*Corresponding author: elham_112@yahoo.com
Abstract
Drying is one of the primary methods of food preservation. Determining coefficients used in drying models is essential to predict the drying behaviour. The present study was conducted to compute effective moisture diffusivity and activation energy of samples of apple slices. The thin-layer drying experiments were carried out under five air temperatures of 40, 50, 60, 70 and 80ºC, three air velocities of 0.5, 1.0 and 2.0 m/s and three apple slice thicknesses of 2, 4 and 6 mm and constant air humidity of 21%. Results indicated that drying took place in the falling rate period. Moisture transfer from apple slices was described by applying the Fick’s diffusion model. The
effective diffusivity values for all conditions changed from 1.50×10-8
to 1.71×10-7 m²/s. An Arrhenius relation with an activation energy value of 22664.1 to 30919.0 J/mol and the diffusivity constant value of 1.16×10-4 to 6.34×10-3 m²/s were obtained which shows the effect of drying air temperature, air velocity and slice thickness on the diffusivity.
Keywords:
Apple, activation energy, moisture diffusivity, thin layer, Page model
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I am calculating evaporation by the formula used by Datta et al; which depends on the difference of equilibrium vapor pressure and vapor pressure. I have done the model but not sure the range of values of equilibium vapor press or vapour pressure. If anybody done it, can you share what should be the value range ?
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Dear Chandan, what you have to do highly depends on the system you are working on. Maybe you could clarify a bit. What is precisely your fluid mixture? If you fluids hardly mix, the equilibrium vapor pressures of your liquids will be close to the value of the pure components. In case that the fluids mix, your equilibrium vapor pressure will be lowered. How precisely depends on the liquids. There is a lot of data in the literature on mixtures, so you might find the answers there.
Another factor to take into account is the nature of your porous material. If the pores become below the 50 nm capillary effects might start to influence the equilibrium vapor pressures (look in the literature for the Kelvin equation for capillary condensation). How precisely depends on your fluids and porous material.
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I am going to do research about the use of medical and aromatic plant in food stuffs and am looking for a research partner. Is there anyone who's interested in this field and who would like to join me?
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Dear Shaimaa,
You can just read some good quality papers of mine in association with my Sir (Dr. Kuldeep Dhama) on medicinal plants. That will help you to extend your knowledge and will help you to apply it in relevant research activities which you are planning to do.
Fellowship
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Is there any fellowship for Ph.D students studying in india from central govt or any other agency
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UGC, CSIR, ICMR etc
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Vitamins & minerals.
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I think we need far more information before we can answer your question.
What type of food?
What type of processing?
Regardless of the answers to the questions, the response will be very variable due to the different properties of the different vitamins and minerals, are there any in particular you're interested in?
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Can any one having details of the heat processing of pomegranate juice like temperate and time combination.
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In fruit juices with pH < 3.7, spores will not germinate, so a pasteurization to destruct the vegetative micro-organisms will be sufficient. A very rough guideline for foods with pH < 3.7, to be stored at ambient temperatures, is a P value of 10 minutes with a z = 10 oC.
Tucker and Featherstone (2011): Essentials of thermal processing; Wiley/Blackwell, Chichester, table 4.6 on page 68 suggests more exact pasteurization values for fruits, depending on their pH. His table lists P values at reference temperature of 93.3 oC and z = 8.9 oC.
Unfortunately, Tucker does not list pommegranate juice, but if you have measured the pH of your juice, you can find an indication of the P value in Tucker’s table 4.6.
Sometimes in fruit juices the pH is deliberately lowered by adding small quantities of lemon juice; lowering the pH thus may be helpful to reduce the thermal treatment of the juice, and therefore to improve the nutrient quality of the juice.
The P value (sometimes referred to as F value) is the time-temperature combination, required in the coldest point of the product. Example: a P value of 0.5 min. at 93.3 oC with z = 8.9 min. means: The coldest point of the juice should be raised to at 93.3 oC and kept at that temperature for 0.5 min. The z value helps to recalculate the P value to other temperatures. If the coldest point is z = 8,9 oC lower, so at 93.3 - 8.9 = 84.4 oC, the heating time has to be 10x as high, so 10 * 0.5 = 5 minutes at 84.4 oC.
Recalculation formula of a Pknown at temperature Tknown to a new Pnew at new temperature Tnew:
Pnew = Pknown * 10^((Tknown - Tnew)/z)
So if Pknown = 0.5 min. at Tknown = 93.3 oC and z = 8.9 oC
and you want to find the Pnew at temperature Tnew = 90 oC
Pnew = 0.5 * 10^((93.3 - 90)/8.9) = 0,5 * 10^0.371 = 0.5 * 2.35 = 1.17 min. at 90 oC.
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I am looking for information on starch and protein gelatinization or denaturation during processing? We are working on the subject so we can share some results.
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Dr. Ahmed
I am working in glucosinolate analysis and composition of different Eruca species.
As probably you know rocket leaf contains glucoraphanin, a glucosinolate with antioxidant and anticancer properties. I suppose glucosinolate content will be modified during processing. I wonder if you are also interested in the fate of rocket leaf glucosinolates. If so, we could collaborate in this research.
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Can anybody suggest to me some organic foaming agents and foam stabilizers that can be used for foam-mat drying of tomato paste?
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Dear Mr. Olanyan,
A.S. Mujumdar (Ed.) (2006): Handbook of Industrial Drying; Taylor & Francis, Boca Raton, gives limited information about foaming agents and foaming stabilizers in general :
"Vegetable gum and soluble protein have successfully been used in the food industry as foam-stabilizing agents." See section 21.7.10; FOAM MAT DRYERS (Autors: Shahab Sokhansanj and Digvir S. Jayas)
Also: "Film-forming components used in the drying of fruits and vegetables are glyceryl monostearate, solubilized soya protein, and propylene glycol monostearate. See section 25.4.6 FOAM DRYING (Autors: K.S. Jayaraman and D.K. Das Gupta)
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During thermal scanning of dried pumpkin flour, a sharp melting point was noticed at 158°C. I am not sure whether this is contributed to by lipids or protein, do you have any suggestions?
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Dear Prof Ahmed
Currently work with pumpkin (extruded and dried). In our thermograms pumpkin flour (Cucurbita moschata) dont show melting points at the temperature that you said 158 C..Also in another work we demonstrate that influence of lipids and starch (Amylose - lipids complex increase thermal stability up 95 C). the event of protein denaturation ocurrs at lower temperature than 158 C. At this temperature I agree with prof Islam carbohydrates are contributing to the melting point instead proteins and lipids.
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I am interested in designing an indirect active hybrid integrated solar dryer for the of drying cacao beans, mango slices, and tomato in halves. I plan to present this as my dissertation proposal.
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I believe you are trying to design something like this:
In general, a very interesting and quite helpful book in Solar Engineering is Solar Energy Engineering: Processes and Systems by Soteris Kalogirou. The fig. is from this book.
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In jam and jelly products are made up by many type of fruits, nutrient content also very, so what are common nutrients available ?
The list of parameters available for quality analysis in jam and jelly ?
The standards for good jam and jelly ?
So I requested to can anyone clear my doubts. Thank You.
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if you have to estimate the real fruit content (depending on the fruit cultivar) you can measure malic and isocitric acid, formol number, sorbitol, phosphate, potassium and use the AIJN Code of Practice or the RSK medium values
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Carrageenan in food processing
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Carrageenan has more than 600-year history of safe and healthy use. This is a naturally-occurring product and non-synthetic in any way. Obtained from non-GMO seaweed (marine vegetable) is widely used in food because of its great versatility. The levels of use are very low and so the level of consumption are really minimal, far below many other food ingredients. Moreover carrageenan is not absorbed by the human body acting as fiber and being eliminated undigested (this is because we don't have the enzymes to break down the long chained carrageenan molecules). Most of the controversy came after Dr. Tobacman request to FDA a review about carrageenan safety. Her request was replied recently (see link below).
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I've tried incubation-like fermentation to cocoa bean. This method according to Biehl et al (1982) or Biehl et al. (1985). The cocoa bean incubation at medium acetic acid with duration about 24 hours.
How to make it simple?
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Acetic acid bacteria will growth in the cocoa bean pile after growing of yeast. It is controlled by aeration.
Ethylene Absorber or Scavenger.
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How can I make a low cost ethylene absorber for keeping inside the cartoons of fruit and vegetables.?
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I think you can use potassium permanganate.
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Effects of high pressure on oxidative stability
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Check my paper "High pressure processing of meat, meat products and seafood", You can download it from my personal page. A paragraph is dedicated to oxidative stability of meat products following high pressure treatments.
Microencapsulation of onion oleoresin by using spray drying research paper related
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Research paper related can u send me plze
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Send microencapsulation parameter and analysis
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I have to make some product of buckwheat, preferably chips or flakes, for my Ph. D program. Is it possible? If not, please suggest what other products could be made from the mentioned object.
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Technically you can make buckwheat flakes. The process is simillar to the one used in making oat flakes. The grains are soaked in water followed by pressing between hot roller drums. The degree of starch gelatinization depends on flakes thickness, water uptake during soaking, and thermal treatment conditions. Due to the high fibre content in buckwheat, you may need to modify sensory attributes of the finished product.
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I am looking to ferment pitaya pulp in order to reduce sugar content for subsequent concentration, but I'm not sure to what method of fermentation is best.
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I need to know gum xhantan concentrations to help stabilizing an emulsion
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Use level in salad dressing is typically 0.2-0.4% xanthan depending on the oil content.generally as the oil content of the dressing increases, less xanthan gum is required for stabilization.
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I want to mask the bitterness of Bacopa monneiri (Bramhi ) in RTD beverage mix
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I have already used MD , but its not satisfying..I need something which can mask bitterness completely.
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I need information the pH value should be in the lactic acid fermentation process for making good modified flour
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What do you mean good modified flour is it for making improved bakery products or what? Generally the end point of LAB fermentation when the pH of milk or the media contains the milk reach 4.6
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I need a standart of 2-AP (2-acetyl-1-pyrroline) for analisis in GC/MS. Anyone ever synthesized this compound?
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Minimal processing of fruits and vegetables at laboratory levels.
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What are you trying to achieve, and what is your objective?
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I'll explain what the experiment is meant for more deeply: i'll pick up samples of olive pastes from the malaxer at regular intervals in order to create a kynetic model of the evolution of volatile compounds during the malaxation. To stop the lipoxygenase cascade, that lead to the production of volatiles, i need a chemical agent inside the vial that will be filled with some grams of olive paste. That will stop the reactions and freeze the volatile composition at the time the sample was picked up. The vials with sample and inhibitor will be stored in freezer until analyses. I've found some indications in the literature about Calcium cloride saturated solution as an inhibitor, if you know of more and/or better inhibitors i'll be grateful if you could share. Thank you in advance.
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Microwave Blanching
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I need a low cost, simple solution.
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I'm afraid the question is not that simple. It depends on the target materials and the quality of end products that you want. Define purity that you would like to achieve. Ask yourself if it is necessary to "separate" them? Because anthocyanins are not "one" compound, they are a group of natural compounds and one may have distinct properties compared to the other. I suggest you provide specific details for whatever you're interested in, then you may likely to get what you want to know here.
If none of any quality issue is your concern, press and spray-dry would be the most simple solution.
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Edible berries change color quickly due enzymatic reactions.
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Irradiation, dipping in organic acid, modified storage condition etc may be useful
How to prepare sodium caseinate
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Microencapsulation
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I am trying to produce a rice drink on a laboratory scale and would like to know which grain is better, malted grain, brown grain or white grain?
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Then it depends what you mean by "better" - better for what?
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Any formulae?
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or this. It depends what you would like to calculate
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I need to know the best methods for producing corn starch to evaluate those methods technologically and economically
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Purple sweet potato properties
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The study was to provide the theoretical basis for development and utilization of pigment from purple sweet potato.[Method] With purple sweet potato variety Chuanshanzi as the material,the basic physicochemical property of its pigment and the effects of pH value,temperature,light,oxidant and reductant and metal ions on the stability of pigment were studied.[Result] The pigment from purple sweet potato was easily soluble in water,methanol and ethanol,but insoluble in acetone,ethyl acetate,ether,and petroleum ether.When the pH value of aqueous solution of pigment from purple sweet potato was 1.0-3.0,the properties of the pigment was stable,bright red,and with the increase of pH value,the pigment colour became shallower,and its degradation index increased.When the temperature was 20-60 ℃,the properties of the pigment was stable,and when the temperature was over 60 ℃,the stability of the pigment was decreased rapidly.The effects of light on stability of pigment was little,after 8 d continuous irradiation,the preservation rate of pigment was 87%.The oxidative resistance and resistance of ascorbic acid reducing power was poor.Al3+ and Zn2+had an effect of protecting the color of pigment,and could improve the stability of the pigment,but Fe3+ had a destructive effect.[Conclusion] The pigment from purple sweet potato was a kind of water-soluble natural pigment,and its main composition was anthocyanin substances.
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As per book reference, 60 brix. is prepared by 60g sugar in 40g or ml of water, giving a solution of 60 brix. but I am not getting the correct brix value. How do I prepare 100 ml solution of 60 brix. representing sugar concentration in brix or just percentage of sugar for 100 ml solution - which looks better for research work?
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Degrees brix is the % w/w of soluble solids in a solution. If the only soluble solids in the solution is sucrose then it equal to the sucrose concentration. Can be determined by using a refractometer.
To answer your question, it depends on whether the final mass of solution (60 degrees brix) you want is important or not. If you want 1000 gm of 60 brix solution as your product then weigh 600gm sucrose and add water until you obtain a total mass of solution of 1000gm. If the final mass is not important start with 1 kg of water and add 1.5 kg sucrose and you will have the same concentration.
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Best drying temperature for pasta.
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For long goods, the first stage of drying is carried out in the pre-dryer where the moisture content is decreased from about 30 percent down to around 17 to 19 percent . In the case of short goods, the moisture content has already been lowered and decreases from about 25–27 percent down to between 17 to 19 ercent. The pasta, long or short, then moves into the final drying phase where the moisture content is further reduced to about 12.5 percent. The product is then stabilized so that the moisture remaining within the product can redistribute self evenly so that there are no stressful moisture gradients from the center to the outside of the product. If the product is not provided with appropriate stabilization, stress fractures or checking may develop. In the case of long goods dampening step may follow stabilization to slightly increase moisture content and further stabilize the product and thus protect it from cracking. The product must then be cooled to a temperature (28–32ºC) close to that of the surrounding. Low temperature drying processes are now considered the traditional means of drying. High temperature (HT) drying at temperatures of 60–85ºC was introduced to the industry in the 1970s and early 1980s. The initial driving force behind the development of HT drying was improved bacterial control for egg products. Another immediately recognized benefit was much shorter drying cycles (8 h) that permitted more compact drying lines for a given capacity concomitant with a reduction in the high capital costs associated with plant space. As HT drying cycles became operational, it was discovered that an additional benefit was improved cooking quality and better color. Once the benefits of HT drying to product quality became generally recognized, HT quickly became the process of choice for most pasta manufacturers worldwide. In the past few years, the application of ultra-high temperature (UHT) drying (85–110ºC) has become common, with drying times as short as 4–5 h for long goods and 2–3 h for short goods. UHT drying reportedly produces pasta products with cooking quality and color equal to or better than that obtained with HT drying. For more detailed please tak e alook at to Gavin, cereal product manufacturing Good Luck
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Dehydration techniques
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Osmotic dehydration of fruits involves dipping fruit slices in concentrated sugar syrup for specific duration taking it out and hot air drying. Now the issue here is that there are 13-14 parameters which affects mass transfer important one are which fruit, variety, stage of maturity, size of slices, osmotic agent, concentration of syrup, ratio of fruit to syrup, duration of dipping, atmospheric pressure, stirring, temperature etc. Hence under this back ground asking detailed process of OD of fruits is not a proper question. The question should be specific in terms of fruits/variety etc.
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I am eager to collaborate with researchers in the area of resistant starch as I am preparing a research proposal on the subject. The researcher/s should have good knowledge of starch chemistry and measurement of RS including X-ray diffraction. I can take care of the other part. A Post-Doc position will be considered for a candidate having experience in the field.
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Salam Ida. It is nice to get a response from you. I am more interested on your research since I also worked on nanopackaging and currently I do have a antimicrobial nanopackaging project. We can collaborate.
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Cell wall mechanical properties consideration during food process is concern in my research.
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Dear mohammd
You can use distructive and nn- distructive methods for general strength of middle lamella of apple tissue
By a texture analyzer In TPA test cohesiveness which indicates rigidity of internal bounds can be determinative.
But You can try Ultra sound and also Raman specterscopy for this, which is more investigative.
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Pulsed electric field effects on fish and fish products
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From your country Turkey, Nadide worked on Ohmic heating of meat in Canada few years back.
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I conducted an ultrasonic assisted extraction (UAE) for phenolic compounds of seaweed and found that lower solvent/solid ratio extracted higher phenolic. Any idea how this happens?
Do UAE and conventional extraction have the same rule?
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You have to optimize solvent to solid ratio and of course you should consider the ultrasound effect on the extraction. You can run a control sample to establish the hypothesis.
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I analyzed my liquid food sample for total polyphenols by chemical method and run the same sample with range of dilutions in FT-NIR and got the spectra. Now, there are various peaks in the spectra. How to select the wavelength which corresponds to polyphenols. I would be very grateful if anyone could suggest any book or step by step process of interpreting the spectra . Please help.
Can someone advise on pH loss in Food Products during storage?
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Can anyone explain the possible reasons for pH decrease in fruit and vegetable processed products during storage.
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Asides microbial reasons, since the pH of your sample is around 4.1-4.4, if stored at room temperature (25C) you cannot rule out completely the gradual or slow loss of moisture from the tomato puree which will subsequently increase the sample concentration and hence a decrease in pH.
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I like to document the elements present in my fruit sample. Came to know about this EDX spectroscopy and hope it will serve my purpose. My question is whether a single run itself will give a spectrum with all elements which are present in the sample? And how estimation of each elements is done?
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When used with 30kV electrons (within a SEM), EDX (or EDS) will give you information on all elements on the sample with confidence (Z>~5-6) in a single spectrum. The spectrum must have high statistics: major peaks with more than 10kcounts.
The quantification is done by considering the intensity of the peak of each element and some corrections (for fluorescence, absorption, etc). The quantification is usually reasonable directly from the EDS software but care must be taken on light elements (Z<10). Since light elements will be abundant on your sample, it may be difficult to evaluate properly the amount of the other elements. Usually, the sample must be flat and at the exact work-distance.
If you need to find trace elements (concentration below 1%) or need high accuracy (error below 1%), you may need standards and very careful acquisition.
Any body can send the soft copy of this paper: - Concentration of tomato juice and other fruit juices by reverse osmosis D. Pepper, et al
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Journal detail not available
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How to determine the stability of emulssion systems? Which method is preferable?
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To my opinion, rheology could be used but in conjunction with other methods. You should keep in mind that emulsion destabilisation can result mainly from creaming (or sedimentation depending on the relative densities of the dispersed and continuous phases), flocculation and coalescence of the droplets. I would propose to keep the emulsions in standardized steady conditions (controlled-temperature), to look at creaming and/or oiling-off (naked-eye observation ; some instrumented systems also exist) and to make droplet size measurements (light scattering or light diffraction methods ; its depends on the size of the droplets ; you may also use microscopy + image analysis)
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...
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You cant eliminate salts but you can reduce it.
In the case of alkaline-conditioned type B (basic) gelatine, both asparagine and glutamine are almost completely converted to aspartic and glutamic acids respectively. The amino acid composition of collagen and an acid-conditioned type A (acid) gelatine hardly differ. This explains the different
iso-electric points (IEP) typical of types A and B gelatine. For gelatine of type A, this corresponds to collagen at about pH 8–9 and for type B at pH 4.8–5.5.
Please do not hesitate to contact me if you had any questions...
Good Luck
How much amount of Nutritional composition ?
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Tannin, Ferrous reducing power and Flavonoid content of amla fruit
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Some reactions, such as acidity and vitamin C analysis, analysed based on the end point pink color appearance or disappearance, but color of jam is red it also give false positive results.
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Well a simple solution, you may try monitoring the end point of titration using a pH meter.
Like for example in acidity analysis, your pink colour change is around pH 8.2.
For your spectro analysis you may try diluting your sample and use a blank jam sample to tare.
Provide the information of sweet maker or halwai
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Provide the information of sweet maker or halwai
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A new custard recipe formulation was recently made using Cocoa powder. The Custard has very low gelling capacity which need to be adjusted.
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As Mr Ramrez said yes Tgase is powerful crosslinker but it need a proteinous medium, so you must have geleing agent like gelatine in your formulation.
And Try MP tgase, which is more general and also restricts high acidification.
In ajinomoto try to contact Mr.Ishida Rikiya , He can help you easily.
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Is it possible to use flue gas analyser instead of headspace analyser in Modified atmosphere packaging?
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It depend on the kind of gas you want to detect. For the detection of O2, CO2, CO and the amount of CH4 in a package you can use a flue gas analyser. For the detection of organic gases like alkenes or alkines it is better to use a special gaschromatograph or GC-MS.
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I want to produce margarine through crystalization of oils at 500kg/day, which translates into about 80kg/hr. Anyone know where I can get such a small plant? All suppliers can only supply 500kg/hr and more.
I currently want to research into value addition of fish can anybody suggest research areas to me.
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Value addition of fish
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Even after grinding the tomato peels in a mixer and a ball mill, it remains like flaky particles. So can anyone guide me with the cheapest and best way to powder these peels?
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it depends on the quality you want but a fluidized bed should do the job quite efficient. When they are crispy, you could use a coffee mill to realy pulverize your paricles
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  Should respiration heat be considered as a factor affecting the vacuum drying process? The question is based on some experts' opinions on this effect.  
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