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Hi everybody
I tried to work with 1-octanol in order to avoid bubble formation during the whole digestion process. However, it did not work since during digestion with sodium hydroxide there was a huge bubble formation and the food sample gets trapped in the upper walls of Erlenmeyer flask. What antifoaming agent do you recommend?
Thank you very much in advance.
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Dear Silva , My lysis buffer contains 10mM imidazole, 300mM NaCl and 10mM TrisCl pH 8.0.
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Does anyone have the scientific evidence of the health effects of probiotics? I mean, what do they secrete specifically or how do they help the digestive system?
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I am trying to design an agricultural and horticultural calendar for Karbi Anglong and Dima Hasao districts of Assam, India. What are the steps that I should begin with?
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Other people in my lab have used NormFinder but I'm trying to find other options which are user friendly as well
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Dear Sir/Madam, My name is Salsa Meidika from Food Science and Technology Sebelas Maret University Indonesia. I am writting a paper about application clove oil in edible coating. But I still confuse which it better to make edible coating from guar gum or alginate-chitosan? I would like to thank you in advance. Yours sincerely, Salsa Meidika
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If I were to receive an import of a new fruit species in the country and, upon arrival, the whole lot was diseased, what steps do I take to diagnose and solve the problem? Is there a general procedure or scheme followed for post-harvest management to identify the cause of the unknown disease?
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I'll be conducting my thesis in Japan soon and I want to know what is the best method to personally bring viable microorganisms (specifically Lactobacillus spp.) in-flight.
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I recommend
Girish Korekar
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best wishes
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Milk-loving people, let’s discuss this video! I'm for sustainable agriculture and I agree that Remilk is revolutionary but there were points in this video that got me thinking:
1. “Milk is not healthy” is a broad presumption. Sure, there have been researches that were for and against consuming milk. But I consider milk as a healthy food since it contains proper amounts of dietary fats, proteins, vitamins, and minerals needed by the body. It is a reason why dietary guidelines (such as issued by the United States Department of Agriculture) recommends consuming three daily servings of low-fat/non-fat milk, yogurt, or cheese.
2. Alright, milk may be bad for consumers who can’t tolerate lactose. But how about in fermented milk products? During fermentation, microorganisms utilize lactose and produce lactic acid. I can think a lot about how lactic acid production is important in fermented milk products.
3. Milk has cholesterol but a cup of whole milk only contains 0.01% of cholesterol. How much more in low-fat or non-fat milk? Also, milk consumption increases HDL (high-density lipoproteins) cholesterol which transports excess cholesterol from the bloodstream to the liver for bile production. Bile serves as an emulsifier in the digestion of dietary lipids.
4. Indeed, milk is predominantly comprised of saturated fats. However, these saturated fats can be converted to unsaturated fats by microorganisms (e.g. lactic acid bacteria) during fermentation.
5. I can agree that milk is not entirely sustainable in the sense that the dairy industry greatly contributes to greenhouse gas (GHG) emissions compared to other agricultural practices. But we can’t ignore that there has been a significant reduction in GHG emissions throughout the years primarily by changes in breeding, nutrition, and management practices.
6. I honestly don’t know what to feel about animal abuse in the dairy industry. Does continually breeding dairy animals and leaving them in a lifelong cycle of reproduction and lactation might be considered animal abuse? (In my mind, it's a sad yes.)
7. Let’s say that the microbes have the same machinery as the cow’s mammary epithelial cells in producing milk, is it certain that they will have the same physicochemical composition, property, and functionality?
8. What are the external nutrient sources of the microbes? Is it the same nutrients found in the cow’s blood?
9. It is contradicting that they want to produce milk from microbes with the same chemical composition as cow’s milk but with no lactose?
This video discussed valid points that can be considered problems in the dairy industry. As long as this microbially-produced milk does not sacrifice the wonders of milk; Remilk, why not?
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I agree with you why not.
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Deepwater rice cultivars found in various regions around the world have their own differences. Please mention how the deepwater rice cultivars of North-Eastern India varies from that of Southeast Asian Countries. Also, suggest any references.
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I am looking for literature on stock cubes/bouillons' industrial methods of production especially in regards to stability and overall quality.
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1- Development of bouillon cubes from souari nut pulp: formulation and physicochemical and sensorial evaluations
2- Formation of mutagens in beef and beef extract during cooking.
3- Estimation of population iodine intake from iodized salt consumed through bouillon seasoning in Senegal
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When i start doing literature i observed that most of the authors used pre-trained CNN models for the identification and classification of plant leaf diseases. Why none of the authors concentrated to designed customised CNN model for this problem? is there any particular reason?
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To make a robust CNN model it requires a large number of pre-labeled data sets. Which is quite difficult while tackling a practical problem. Moreover, the training of a model is a time-consuming process and requires a large storage space, which is quite costly in general.
You are right that a pre-trained model is highly customized with its parameters and size but the impact is low when you trained over a large number of data sets.
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I'd like to know what is high oxygen MAP?
And what kind of food use it to prolong it storing time?
Thank you!
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Generally, red meat with a high level of myoglobin is packaged in HiOx-MAP .
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How much raw materials are required for producing 1 kg of final products for each of the following?
1. Orange jam 2. Orange Jelly 3. Orange Marmalade 4. Tomato sauce 5. green Chilli Sauce 6. Tomato puree 7. Ginger paste 8. Canned pineapple
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Hi there sadhan
search the product you wish and it will give you its composition.
good luck
isaac
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In the protocol for the extraction of anthocyanins from plant material, the first step is the sample preparation. The sample is prepared by converting the plant material into a powdered form after mixing it with liquid nitrogen. Is it necessary to mix the plant material with liquid nitrogen or can we proceed without liquid nitrogen to convert plant material into powdered form?
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The liquid N2 is to keep it cold, make it brittle, and exclude O2. The success otherwise depends on the properties of the particular material.
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Can anyone help me how to increase the shelf life of suji (sooji). What are the factors affecting shelf life of suji?
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Rava get insect infestation fast .Insect is Tribolium ...we can see eggs...larvae...pupae and adults in Rava...if not properly stored..Any cannot have freezing technology.
Traders ...you get rid of that at your point. A machine I developed recently to crush eggs etc and remove adults..
Soon coming to market.
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FTIR technology is considered the most advance for the detection of adulterants in milk. Is there any mathematical relation that can describe the relationship between the amount of adulterants in milk using the absorbance from the FTIR? Please suggest any research articles that describe this or related areas.
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Relation between milk with adulterants . Many times urea is added in the milk as adulterant to increase the density. If you is isolated then in FTIR it shows the absorption for NH2(V NH = 3200-3350 cm-1) and C=O) at (v 1700 cmi1).
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I want a sample preparation method for lowry & biuret method for protein quantification from curd, cheese, paneer that I prepared from ground nut milk. Kjeldahl apparatus is not present in working conditions, so is it possible to quantify protein content by biuret/folin-lowry method?
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Total protein content from groundnut milk products like curd, paneer, cheese etc.lowry & biuret method for protein determination is used.
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Pineapple juice contains not only sucrose but also glucose, fructose, etc.. I wonder if by determining the degrees Brix of a sample of pineapple juice, i will obtain only the sucrose content of the sample, or if i will obtain the content of all the mono and disacharides of the sample.
Thanks in advance for your answers
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Degrees Brix (symbol °Bx) is the sugar content of an aqueous solution. One degree Brix is 1 gram of sucrose in 100 grams of solution and represents the strength of the solution as percentage by mass. If the solution contains dissolved solids other than pure sucrose, then the °Bx only approximates the dissolved solid content. The °Bx is traditionally used in the wine, sugar, carbonated beverage, fruit juice, maple syrup and honey industries.
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I am working on lecithin and want to convert it into solid powder by spray drying but problem is that lecithin is sticky in nature. When I am performing spray drying particle get stuck on the wall of spray dryer. I want lecithin material in powder form so I can store it for long time without affecting the particle size and powder can be easily suspended in water. So can anyone tell me what material can be added to lecithin to convert these sticky material to nonstick powder form.
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You can use carrier like maltodextrin
And mix with protein and use homogeinzer before spray dryer
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At both very high and very low water activities, lipid oxidation rates are high compared to the rate at intermediate water activities. What can explain this trend?
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The relationship between rates of lipid oxidation and moisture is complex. The amount of water, the water activity and the state of water in a food, along with other factors, must all be considered.
For most fresh or tissue foods that have moisture contents between 60 - 95% have a water activity very close to 1.T he mode of deterioration at this water activity is generally microbial or enzymatic in nature. Direct lipid oxidation (i.e. not enzyme-mediated) is not an important source of deterioration at this high water activity since other modes of degradation will deteriorate the food first.
Concentration, freezing, and drying are mechanisms by which the water activity of food can be reduced. Such processes may bring the food into the intermediate moisture or low-moisture region where direct lipid oxidation becomes a more important mode of degradation. Also, during dehydration, free radicals can be formed which accelerates lipid oxidation. Freezing can also lead to the acceleration of lipid oxidation rates through the concentration of substrates and catalysts in the unfrozen portion of the system.
On the other hand, Chou et al. (1973) found that water activity primarily affects matrix swelling and thus substrate/reaction site availability as well as catalyst mobility.
Hereinbelow the tow common theories related to the relationship between water activity/content and lipid oxidation are briefly discussed:
Monolayer theory
Unlike most aqueous chemical reactions, the rate of lipid oxidation that takes place in the oil phase is observed to increase as water activity is decreased below the monolayer (i.e. water molecules that are bound tightly to the food surface). This can be explained by considering the role of water in this reaction. It has been suggested that the monolayer of water—or rather, the water saturation of polar groups in lipids—is necessary to cover the surface of the lipid, preventing it from direct exposure to air. This monolayer is essentially “bound” water with limited mobility and is assumed to not participate in chemical reactions. Several studies have found that a variety of foods are most stable to lipid oxidation at a relative humidity or aw consistent with the monolayer.
On the other hand, water can form a hydration sphere around metal catalysts such as Cu, Fe, Co, and Cd. In the dry state, the metal catalysts are most active. As water activity increases, the metals may hydrate which may reduce their catalytic action thus slowing the rate of lipid oxidation.
This monolayer theory, however, cannot be applied universally.
Glass transition theory
According to the glass transition theory, one important function of water is its ability to act as a plasticizing agent. The plasticization of a matrix involves swelling of the polymer matrix when moisture is increased. The resulting increase in free volume might allow for faster diffusion of substrates in the aqueous phase which may lead to faster reaction rates. Plasticization may also increase the contact of the absorbed aqueous phase with the lipid phase. The number of catalytic sites increases such that the rate of lipid oxidation increases.
The above discussion shows that water plays both protective and prooxidative roles in lipid oxidation. In some foods at low aw near the monolayer moisture content, water is protective, presumably because it provides a barrier between the lipid and oxygen.
While the classic food stability map proposed by Labuza et al. (1972) shows lipid oxidation having a U-shaped relationship to aw, no U-shape was also observed; lipid oxidation actually slowed as aw increased as the case of freeze-dried food.
Overall, monolayer and glass transition concepts might not effectively predict lipid oxidation reactions in some foods if oxidation is primarily occurring in the lipid phase and thus would not be significantly impacted by water and the physical state of proteins and carbohydrates. On the other hand, water can play a major role in lipid oxidation chemistry if reactions are primarily promoted by water-soluble prooxidants such as metals. Unfortunately, the causes of lipid oxidation in low-moisture foods are poorly understood, which could be why measurements of water activity, monolayers, and glass transitions do not consistently predict lipid oxidation kinetics.
Sources:
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Hello,
I would like inquire on the process of extraction of protein contents from the green pea by means of decantation. What I know is that a decantation is a separation process in which leaching and washing occurs with end result being protein isolate. It takes in milled pea powder, mixes it with water to form a solution, and then processes it to get separate nutrients. Specifically, I would like to inquire about which chemicals and the amount of those chemicals added in this pea solution that can effectively extract the protein content from a pea in the decanter.
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Thank you Professor Li and Professor Niamah, this is very helpful. The study from Dr. Talab that is posted is very detailed. However, how would it be possible to apply this in an industrial scale using machinery? Would a decanter work for centrifugal separation or are there varying machines? Also, would it be possible to get similar studies that have more metrics such as the volumes of solvent to solute?
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Hello,
Can someone tell me how to increase the shelf life of pickles to 6 months to 1 year..?
Below are details
- Should not have artificial preservatives
- Packaging should be glass bottles
- Quality of the product should not deteriorate (Taste and authenticity should remain same)
- Cannot use Retort because it is deteriorating the taste of the product.
Thanks,
Balasubrahmanyam
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The Indian pickle already contains salts, sugar, oil and spices as basic ingredients. These ingredients act as preservatives itself, there is no need for the extra preservatives. Salts and sugar works on the principle of osmotic pressure on microbial cell wall result in disruption and spices acts as antimicrobial agents. The oil layer creates anaerobic conditions in pickles by reducing oxygen supply which may inhibit microbial growth. In addition, the shelf life of the pickles can be enhanced via refrigeration in airtight glass/plastic jar.
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Does it have something to do with its ketone group or a different property? Please explain.
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Dear Alexxandra,
very good thinking. In aqueous solution, fructose is an open-chain to a small extent and is present predominantly as α- or β-fructopyranose, which partially merge by mutarotation. In crystalline form, fructose exists as a closed pyran ring (fructopyranose). The keto group which is only present in fructose's open chain form has now turned into an OH- group by nucleophilic substitution during ring formation. Therefore, the keto group doesn't play any role in incorporating water into fructose's crystalline structure. Crystals of fructose exist as either anhydrous β-d-fructopyranose or as the dihydrate or hemihydrate (one molecule of water of crystallization per two molecules) of β-d-fructopyranose. Dihydrate fructose crystals can dissolve in their own water of hydration and must therefore be handled very careful. By the way, the water of crystallisation is not chemically bound, but only weakly bound by hydrogen bonds (electrostatic forces) and may normally be removed by heating.
Wishing you best of success,
Johannes
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We are analysing the traditional ways of cheese-pressing in the Basque Country. There are many materials about cheese and cheese-making, but, unfortunately, we have not found anything about pressing processes. It would be very interesting for us to know more about pressing strategies around the world.
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It is fascinating indeed. Personally I find different types of cheese as one of my most favorite foods. They boost my energy and supply my mineral needs as well.
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Once I found out that nitrogen gas removed my anthocyanin more than its solvent (ethanol)
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Vacuum drying and freeze drying would work well. However, freeze drying is an expensive and time consuming method.
Vacuum drying is one of the the ideal methods for drying materials sensitive to heat or oxygen due to the advantage of drying at low temperature and minimizing the possibility of oxidation reactions. Since you are working with bioactives you will have to be careful with the temperature you select.
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I am looking for an efficient way to dry rice seed after surface disinfection and inoculation with fungal spores. Literatures mentioned that they did air dry, but this did not seem to be insufficient to me. it might take hours to dry 3 ml of suspension that i am going to use. The limitations are the samples should not be exposed to high temperature which might inactivate fungal spores and blowers that would cause spreading of fungal spores after drying. Does anyone have a good idea?
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Expose the seeds to cold plasma.
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Does anyone know about oat beta glucan (high viscosity & purity) supplier for bigger amounts e.g.10-100 g?
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Beta Bio Technology has high purity (up to 85%) oat beta glucan, try with them
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As you know, in Malaysia we do have a lot of honey from Bee and Trigona Bee (Kelulut). So, in what aspect, it will determine that the honey contain is 100% pure without any substance in it?
Any analytical instrument that I can use to determine it such as HPLC, TGA, GC-MS, FID, Zetasizer, AAS, UVVIS, etc?
Some say in order to determine the real "honey", you need to bring it to your home and see your wife reaction.
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High Fructose (corn syrup) sugar is now a prime diluent in Chinese honey, and other imports to USA. This is a huge problem in international honey sales. Fructose can be separated from other hexoses by liquid chromatography.
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The material (besides clay) needs to be non-reactive/stable, and preferably synthetic. Thank you very much in advance! Your suggestion is very much appreciated!
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Zeolite ?
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Dear colleagues, could you please help me with some references toward the the literature related to alternative food systems. In particular I am interested into the information systems used/designed/developed for the alt food sys and their participants information behaviour. Also non academic links to related content is welcome.
Kind regards
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Guys,
I have been freeze-drying Vancomycin for some studies. But since the last three batches, the number of vials breaking during lyophilization are too much!
I haven't changed the material vendor, nor the cycle parameters. Even the lyophilizer is the same. Can anyone please help me out?
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Dear Vemparala,
OD = outer diameter of the vial. Note, this may vary up the height of the vial, it is often bigger where the base of the vial joins the side, there may be a bulge.
Tray band = ring surrounding the tray of vials. This has a fixed size. If you have a full tray and need "force" the vials to fit in the band, not uncommon, it is ideal to have a tight pack of vials, just not "too" tight. However much "too" tight is!
Heterogenity = unless you control ice nucleation, all the vials will freeze at a different time. You will then have different ice crystal structures in each vial. The vial that cools more before freezing will have small ice crystals and the vial that cools less will have larger ice crystals ... you then do not have the same condition across your vials, they are different.
A full webinar on freezing from a true expert can be viewed here:
Look for the 2018 webinar by Dr Margit Giesler;
The Freezing Stage in Freeze Drying: Fundamental Concepts 2.0
You will have to register to view, but there is no charge.
Kind regards
Rob
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I want to make some testing kit-like formalin for fruits, vegetables, fish, milk etc or carbide for fruits etc.
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Formaldehyde may be detected using the following reagents:
1. Phenylhydrazine hydrochloride + acidic hexacyanoferrete (III) (pink or purple color, color intensity is proportional to formaldehyde amount).
2. Phenylhydrazine hydrochloride +acidic Potassium hexacyanoferrete(III)(pink or purple color, color intensity is proportional to formaldehyde amount).
3. Almost same as previous, addition is impregnation of Silica gel.
4. 3-methyl-2-benzothiazolone hydrazone (MBTH) + acidic Iron (III) Chloride (Blue). [Note: highly acidic condition; pH <1.0; UV-vis 630nm]
5. Chromotropic acid (2,4-Dichlorophenoxyacetic acid) (chromotropic acid in 75% sulfuric acid reacts with formaldehyde; peaking at 580nm wavelength).
6. Chromotropic acid + Bisulfite solution.
7. Chromotropic acid + 1% Sodium bisulfite solution.
8. J-acid (6-amino-1-napthol-3-sulphonic acid; 7-Amino-4-hydroxy-2-naphthalenesulfonic Acid; CAS No. 87-02-5; Sigma: 08800 FLUKA) (University of Cambridge; PhD Thesis: A new J-acid method for the detection of formaldehyde; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.599295) .
9. Phenyl J-acid.
10. Mixture of dichlorosulfitomercurate (II) complex and acid bleached parasoaniline hydrochloride.
11. Formaldehyde + Mixture of dichlorosulfitomercurate (II) complex and acid bleached parasoaniline hydrochloride. (Schiff’s test?!)
12. 5,5-dimethyl 1,3-cyclohexanedione (Dimedone, Methone) (Sigma 38490 FLUKA).
13. 2-hydrazinobenzothiazole (along with 1% ferricyanide and 10% sodium hydroxide; deep blue colour in presence of formaldehyde) Sawicki and Hauser (1960).
14. 2-Hydroxycarbazole Reagent: Yellowish to Dark Blue colour
15. Nash/Hantzsch Reagent (2M ammonium acetate, 0.05M acetic acid, 0.02M acetylacetone): gives yellow colour; can be measured using spectrophotometer at 412nm
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Hi,
I'm performing TBA assay to measure the degree of lipid oxidation of raw pork, using the steam distillation method with Kjeldahl distiller.
I collected 50 ml of distillate, and it didn't react with my TBA solution so didn't develop the reddish-pink color which can be absorbed at 530 nm.
The distillate should contain some amount of malondialdehyde, but I think my distillate contains only pure water without malondialdehyde.
If the heating temperature is high, distillate is collected very quickly, but it seems to contain only water. So I tried to decrease the heating temperature, then the distillate was just not collected at all.
Please help me, find anything wrong in my procedure...Here's my procedure.
10 g of pork + 97.5ml DW + 2.5ml 4N HCl  ==> Blending, homogenizing
Put it into Kjeldahl flask+distiller
The collected distillate is reacted with 0.02 M TBA reagent dissolved in 90% acetic acid in 100'C for 40 min
The absorbance is measured at 530 nm
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Cheese making is similar in most of the places of the world. Indeed, it is an acidification process of the milk. However, depending on the cheese variety or geographic location some small (and not small) differences appear in the manufacturing. We are interested in the pressing processes used in the manufacturing of the different varieties of cheese. Which are the usual pressures used to get out the whey from the curd before the curing?
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Interesting… I have found more information:
“Pressing is applied to extra-hard, hard and semi-hard cheeses, and the pressure varies with the cheese variety; usually ~0.5 bar (1200 kg/wheel) for most hard cheeses and up to 6 bar (2000 kg/wheel) for Emmentaler.”
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The Haloumi is the traditional Cyprus cheese made from the cow or sheep milk. What is the normal average yield of halloumi cheese?
Will it be possible to slightly improve the yield by addition of calcium chloride in the pasteurized cow milk? How much yield improvement can be achieved if so?
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In one of the practical courses, that I have taught several times, the students make white cheese from cow's milk "but similar to Halloumi" using calcium chloride. CaCl2 enhances curd formation, raises acidity a little, and restores the calcium levels (since part of it is lost).
I have not observed a "good" increase in the yield of cheese as a result of adding this salt but the first 2 benefits, above, point to that there will be "some" increase.
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Precooling temperature chart for green leafy vegetables.
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I tried to determine the protein concentration of protein isolates at 280nm but i was not getting any reasonable results despite the various dilutions. Is there any other method or procedures i can use without using any reagent? Thank you.
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The most straightforward psectrophotometric method for quantitating protein content in biological samples is the Bradford method ( ) which involves the binding of the dye Coomassie Brilliant Blue G-250 to protein that causes a shift in the absorption maximum of the dye from 465 to 595 nm. The increase in absorption at 595 nm is monitored and appropriate dilutions of BSA protein are used to prepare a calibration curve based on this external standard.
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Recently, the isolation of protein from protein-rich plants using various isolation methods has increased tremendously to meet the protein requirement of people, enhance the utilization of such plants and sometimes as functional food ingredients.
However, the protein contents of protein isolates obtained via various methods such as micellization and isoelectric precipitation from the same sample are expected to be closed with micellized protein isolate probably having the highest protein content. What could then possibly caused a significant difference between the protein contents of micellized and isoelectric precipitated protein isolates of a sample with micellized protein isolate having lower protein content?
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By micellization, isolating proteins is easier. All proteins in the presence of available electrolytes are folded into micelles, and then removed by centrifugation, ultrafiltration. Рroteins are separated by an isoelectric point (pH); each protein has its own isoelectric point when it is not charged. To create pH, it is necessary to prepare a buffer solution of a composition of certain salts.
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Can someone please share some text on accelerated shelf life testing at elevated temperature AND elevated relative humidity?
(37 Deg C+ 90% RH).
Thank you!
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See chapter 12 in my book FOOD PACKAGING: PRINCIPLES & PRACTICE (2013) pp. 354-359.
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I'm wondering if its possible to use Tween 20/80 as a carrier/solubilizer to dissolve a hydrophobic substance. So far, I tried heating either Tween to around 70C, and it manage to dissolve my hydrophobic substances. But when I remove it from the heat plate, it starts to turn into like white solid like ghee, which I guess happens because of the decrease in temperature to the cloud point?
Anyway,
I'm trying to understand the differences in both Tween. I read somewhere that tween 20 is better to emulsify small amounts of lighter oils; whereas Tween 80 to emulsify larger amounts of heavier oil.
Then I check the HLB value (wikipedia) in which:
12 to 15: detergent
12 to 16: O/W (oil in water) emulsifier
16 to 20: solubiliser or hydrotrope
Tween 20 (16.7) seems like a better choice as it can act as a solubiliser or O/W emulsifier compare to Tween 80. But then other sources said tween 80 is better to emulsify larger amount of heavier oil?Which sounds like its better to solubilised my hydrophobic substances.
Erm. Do correct me if I'm wrong.
Appreciated.
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you can compare easily between Tween 80 and Tween 20 by mixing your oil with each one of them separately in ration 1:1 at 50 C. then dilute these mixtures with water in ratio 1:1 (mg/ml)then evaluate their transmittance % on spectrophotometer at 650 nm. according to the obtained data, you can choose the surfactant which give the highest transmittance % because High transmittance % of emulsion meaning high solubilization capacity of surfactant for oil which also means higher the emulsion area consequently greater the emulsification capacity of the surfactant
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I wanna to measure  gross alpha and beta in soil, milk ,meat and plant. is there procedure about this topic?
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There is ISO standard for soils and non-salty waters.
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Resistant starch (RS) is recognized as the third category of dietary fiber by AACC. 
For labeling purposes it is still added under dietary fiber.
For commercial purposes, starch is being modified enzymatically and other ways to increase the RS content, so that it can be used in product development. 
What is the difference between a modified starch and resistant starch? or is it that currently RS is being categorized under modified starches?
Kindly give your inputs on this!
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Resistant starch and modified starch refer to two distinct types of material. Modified starch means that the native starch has been chemically or enzymically altered, and typically includes starch derivatives. For starters, just see the Wikipedia entry for modified starch and you'll see some of the various chemical derivatives that can fall under that definition.  On the other hand, resistant starch usually refers to a type of starch structure that is resistant to digestion in the GI tract of humans and other animals.  Quite often, these are partially degraded by enzymes, or derived from plant sources that make a highly branched amylopectin structure that is more resistant to digestion by animals.
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Hi,
I'm currently working on smoothies (which contain key ingredients like fruit juice and milk).
Can anybody suggest how to increase the shelf life of the product to 4 months which has to be stored at ambient temperature? (Suggest technologies other than Retort processing, UHT and HPP).
Thanks,
Balasubrahmanyam.
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Flash pasteurisation is an option that's commonly used. OR add lemon juice to aid in adjusting the pH (depending on the pH of the final product already)
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 hi
I am doing study in migration heavy metal from some food container, I need to know how could I make food simulation , is it citric acid and acetic acid can work in this case  
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3% v/v acetic acid in water is 'acid food simulant' for migration testing in EU standard (from what I could remember).
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I used two concentrations of glucose 0-1 mg/ml and 0-25 mg ml. The problem is that the higher concentrations are similar in color and the lower concentrations a clear difference can be noticed. This situation has led me to believe that may DNS method may be used on very low glucose concentrations. However, I am not sure and I am really in need of your expert opinions.
Preparation of DNS: Mix 30 g of sodium potassium tartarate with 1 g DNSA and 1.6 g of NaOH. Make the solution up to 100 ml with distilled water.
Preparation of glucose standard: 10g anhydrous glucose is dissolved in distilled water and then raised the volume to 100 ml with distilled water. 1 mg/ml was prepared by taking 1 ml from the original stock solution and adding it to 99 ml ddH2O.
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I learned when I was in Spain this method. Levels to mesure glucose in water with good lectures are between 0.2mg/L-2mg/L. 
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Hi,
I have samples of food waste,  consist of rice and chicken meat waste, . I want to digest the samples to analysis crud protein. Also, I ash some samples before I digest to analyize Ca and P. For cude protein samples,the problems are the samples can not digest completely in spite of I use one tablet, H2O2 and H2so4. the temperture for first hour is 220 C and for the second hour is 410 C.The samples become milky color and still like this even I keep them in digester for 4 to 5 hours. Also, after I ash some samples to Ca and P analysis. The samples  are still black color after I have digested for 10 hours in spit of it should be less than 30 minutes 
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ok, I will decrease the weight but may I know can determine the crude protein by NC Soil Analyzer. the mechine for determine nitrogen without digestion. Normally, it use for determine the nitrogin in the soil. Can I determine the nitrogin in tissue samples by this mechine? 
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How to cite codex standards at the end of an article?
For example "CODEX STAN. 247, 2005" General standard for fruit juices and nectars. (by APA standard)
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APA
Joint FAO/WHO Codex Alimentarius Commission. (2007). Codex alimentarius : cereals, pulses, legumes and vegetable proteins. Rome :World Health Organization : Food and Agriculture Organization of the United Nations.
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I need full procedure methods of AOAC for yoghurt Analysis can any body help me?
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Please see the attachment......
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.
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As the above answers all indicate, you would want something that is low in insoluble solids and high in solubles. Clear or relatively clear liquids from non-meat sources would generally fit these criteria, like the whey and molasses that Michael mentions. Cashew juice has also been used in this regard, as has cactus juice. I imagine coconut juice would be another possibility. Cottonseed press cakes have also been used as a source of raffinose and stachyose, with some success. As Khairul suggests, anything that has been pressed for oil extraction might be good. Soy whey might be a good place to look for oligosaccharides like raffinose.
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Is there anyone know simple method to determine fat in fruit juice?
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Thank you Luis Cruz, What method is approximate?
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Food preservation, pre-treatment, food science 
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Pre-treatment is a very broad term and could mean number of different unit operations depending on the ultimate objective as to what the pre-treatment is meant to acheive. e.g in order to prevent enzymatic browning, or enzymatic rancidity blanching/heat treatment is used for inactivating the enzymes responsible for browning/rancidity. Similarly, dehulling of grains is also considered as pre-treatment in order to remove the husk from grains in certain food processing applications. So pre-treatment is an inherent part of any food processing operation and is specific for specific applications.
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I am looking for a technique through which I will be able to cool chocolate as quickly as possible and at the same time, blooming will be avoided. What do you suppose are the best method and cooling temperature?
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IQF, Blast Freezing, Liquid Nitrogen are the methods for quick cooling. But cost effectiveness is the question. I agree with Mr. Upadhayay
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I have a project making "cold brew" coffee. The ground coffee need to steep into water for 20 - 24h, so this is the good condition for the microorganisms grow. I decided to pasteurize the coffee after that but I worried that the temperature will blow away all the flavor and the coffee will turn into odorless... What I need to do in this case? I glad to see any comments of RGers.
Thanks and Regards
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Interesting points on pulsed electric field treatment for retaining the flavour for longer period.
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I’m planning to investigate about the co-processing of food additive, especially hydrocolloids. I would like to contact someone who has worked on the subject, in order to exchange some ideas.
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Dear Waldir,
There are a lot  of people in my research group experienced in starch and its interaction in food systems (including other hydrocolloids). Please have a look at my Research Gate profile. You can find articles which could be interesting for you, as well as contact details to people from my group.
Regards
Grażyna Lewandowicz
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i am looking for articles
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Good points Dr. Benjamin
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I have prepared A research proposal about the reuse of marine by-products as Ingredients of Functional Food. But I have no funding to start my project. Can anyone  recommend a funding organization to support my research or interesting in collaborative with me to do it? I have done pre-experiments and got good results. If anyone interesting in this filed, can contact me.
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Dear Dr Hatab
This is an interesting project  and I would be very interested in collaboration with you too, if you can give me a summary of your research the possibility of funding can be  discussed. I am currently involved in nutraceuticals / functional foods in the prevention of cardiovascular diseases, diabetes, metabolic syndrome etc.
Best wishes and good luck with this interesting project
Khalid
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Food preservation food science 
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Vinegar is used for mayonnaise.  It provides acidity to deliver a low pH which is the primary means of preservation.  The other additives are secondary, maintaining the pH is the primary means of preservation.
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While extracting protease from the B. subtilis containing media, what is the best way to remove protease for Food applications? While adding ammonium sulphate precipitation, the result will be suitable for applications  in food or not? Any methods to carry our protease assay?
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you can used preciptation with amonium sulphate or with aceton and centrifuge then check assay of enzyme after dialysis (just when used NH4SO4)
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Seafood industrial based study.
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Phosphate salts can be used. but residual level is important criteria. This will vary between countries.
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i want to know how the FDA etc. define it, and if it is considered a type of sausage. sorry for my english
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I believe that there are not European standards defining  pâté. Few years ago, in Poland, there were standards describing quality of food products, but not yet anymore. According to old Polish standard  pâté is: ready to eat delicatessen made form cooked meat, fat , liver, other offal and other different ingredients like vegetables, bread crumbs etc. All components should be finely comminuted, mixed, formed  and thermally processed.
As you can see this is rather inaccurate definition.
According policy of European Community, international standards describe only the appropriate test and analysis methods, but not define specific products as well as don't define their quality.
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For the evaluation of Hydrogen peroxide scavenging activity, I found a method described by Wettasinghe and Shahidi, 2000. The following is the proceedure:
Dilutions (0.4 ml) of millet extract were added to 0.6 ml H2O2 (40mM) and volume made to 2.0 ml with 45 mM Sodium phosphate buffer (pH 7.0) was incubated at 300C for 40 min. Hydrogen peroxide scavenging activity was expressed as micromoles of ferulic acid equivalent after measuring the absorbance at 230nm (Wettasinghe and Shahidi, 2000).
Can anyone please clarify me why we are using 45mM Sodium phosphate buffer (pH 7.0) to prepare the reaction mixture?
Reference:
Wettasinghe M, Shahidi F (2000) Scavenging of reactive oxygen species and DPPH free radicals             by extracts of borage and evening primrose. Food Chem 70:17–26.
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A pH buffer, like 45 mM Sodium Phosphate pH 7 buffer, ensures the reaction is optimized (goes to completion) and the ferulic acid peak that elutes is sharp (only the ionized form).
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My institution is considering purchase of new equipment that will replace our old Varian SpectrAA 800. We are considering continuum source AAS from Analityk Jena, polarized zeeman F-AAS from Hitachi and microwave plasma from Agilent. I'm looking for pros and cons of this solutions from users of this equipment.
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In my opinion, I would choose the MP AES Agilent . The instrument is robust and has a low operating cost. The HR CS FAAS, allows the determination of diatomic molecules as NOx, SOx and POx. If these analyzes are in your routine, HR CS FAS would be good. However use may be somewhat limited.
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Hi , 
I am PhD student from Algeria .  I work on wheat gluten and now I am looking for internship to analyse it , I need this appartus :
Fluorescence spectrophotometer for surface hydrophobicity , 
Scanning electron microscope SEM for Microstructure 
DHR 3 rheometer for  rheogical behavior
TA XT plus texture analyser for gel strength and Micro-extension
diffractometer  : X ray Diffraction
bidimentional electrophoresis
Could  someone help me to find this apparatus ? minimum three  . 
Thank you 
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hi, if you want to analize gluten in foods there are to ways to do it:
1. if you want to know if it is present  or not (qualitative method) you can use rapid kits for gluten detections suh as rapid 3D from Neogen(USA) or Gluten Check Flow Through from BioCheck (UK). Easy to use and easy to read, without equipment
2. if you know how much are (quantitative method) you can use ELISA kits like Veratox from Neogen (USA) or Gluten Check from BIoCheck (UK). You need a centrifuge. a water bath and an ELISA reader.
I hope it helps you.
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I need to measure the fatty acids of linseed oil and I have a procedure to measure fatty acids of beef. Do you think I can apply the same protocol for both samples? 
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AOAC method for fat
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I would like to seperate oil from baked product with cloroform and petroleum ether (1:1, v/v ) fractions. I am not sure how can i apply it. Could you explain? How many volume i should add this solution on my sample. For example i weighted 2 g sample in a falcon tube and then add to cloroform-petroleum eter (30ml solution) and shake it then seperate it from falcon tube. Is ıt right ?
And after i obtain defatted extract, doing antioxidant activity analyse is giving true score?
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Well, I don't know exactly hows the matrix but, if you'd like to obtainthe oil fraction from a powder-like product as a GRAS extract, you might try SFE (Supercritical Fluid Extraction), using supercritical CO2 as extracting solvent. You'll need to eliminate most water prior to extaction.
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I always get a lower K content during proficiency testing. Method: AAS .
Dry Ashing: 500 degrees Celsius
Food: Milk (liquid),  Cream and Mustard Sauce
I also have a problem with Na analysis, I tend to get higher results if i use 500 degrees during dry ashing. But if i use 450 degree my results for K increases while Na decreases
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Dear Sir, 
Potassium won't be volatilized at 500 degree, you can refer to the document I attached. Both sodium and potassium can be analyzed quite accurately using dry ashing (not volatile) followed by AAS or ICP-OES method. 
Just a bit curious may I know the whole procedure of your analysis? Do you charred the sample on a hot plate before proceed to ashing using furnace ? Did you spike the sample and compare the spike recovery ?
To be honest we sometime also suffer bad recovery (120%<X<80%), due to nature of sample and contamination. From our experience cream sample sometime frothing during the heating process, causing significant loss of analyte (we don't know at first moment). Sodium and potassium are very abundant in our environment, acid and water used contain significant amount of sodium and potassium which later may cause a higher concentration in reagent blank or sample.
To control it we usually do a spike and QC to check the performance of method. So far we didn't encounter significant loss of sodium and potassium due to ashing unless the analyte loss during other sample preparation steps. 
Hope this can help you. Cheers.    
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ML for Ochratoxin A in milk
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Thanks all for valuable inputs.
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To quantify the melanoidins with respect to the molecular size domains in thin and thick juice , how can I obtain melanoidin standards to use in chromatography? How correct could it be to use pullulans? Is that possible to synthesize a defined melanoidin?
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Dear Mr. Gharib-Bibalan
Thanks for your answer. I have seen similar methods for preparing synthetic melanoidins in different articles, but there are some differences between all. For example , temperature of the thermal treatment shows difference. You suggest 95 C, but is that necessary to provide the  temperature in an evaporation system of a beet sugar factory to obtain the similar melanoidins synthetically, produced in a sugar beet factory? We reach up to 130 oC temperature in process. What do you think about this?
kind regards
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I seek methods to eliminate the natural flora (fungi and bacteria) of coconut meat for inoculation. 
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I would suggest non-thermal treatment of coconut meat. This would likely ensure to retain the nutritional quality of coconut meat.
1. High pressure processing (cold pasteurization)
2. Pulse light treatment (High intensity UV)
3. Nano/micro filtration
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Dear researchers,
I want to add alpha-tocopherol to chitosan film forming solution to prepare chitosan film with alpha-tocopherol. First I added tween 80 as an emulsifier to chitosan film-forming solution(2%) at concentrations of 50, 75 and 100 percent of alpha-tocopherol that then was added to chitosan film forming solution at different concentrations of 0.1, 0.125, 0.15 and 0.2 percent of the solution. Then, it was homogenized with ultra turax at 13000 and 27000 rpm and dried in petri dishes at oven( 30 D. of celsius). Unfortunately, all prepared films showed greasy surface and non-uniform structure. Can any researcher help me how can I prepare a better film with uniform structure? 
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That's right but I think the surface is nonuniform because the emulsion becomes unstable at drying step.
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I am looking for possible off-notes (aroma and flavours) that can be due to carbonation of drinks. I am studying which off-notes can appear due to carbonation or can be attribute to the CO2 in carbonated drink. Any case-study is welcome.
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I agree, if a food treated with carbon dioxide has a flavor off and flavor derived from the deterioration of the food and can not because of CO2. In so red wine is excessive CO2 Known pour augmenter Perceived bitterness of the tannins.
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Is Quercetin structure reversible in different PH ?
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Quercitin is a phenolic compounds. Enzyme and inhibitor complex is rapidly dissociated in contrast to irreversible inhibition.
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Dear Sir/Madam,
I am using immersion heater and it has specs(3kw 418v)and it does have thermostat which can be controled temperature from 30 to 110 degree.
I am using this heater to typical drum (200 ltrs steel drum), the drum containes waste cooking oil (solid state). As you can see the dirty drawing( sorry about my hand drawing), most of oil melted but some of oil is still in solid state.
I calculated that the oil should have completely melt in 3hours at 15degree (atmospheric pressure) but even after 7 hours, still in same state like the hand drawing.I set the temperature of heater @ 80degree, thus the heater turned off at 75~76degree( its what the manufacturer says) automatically.
Does anyone can let me know the solution of even the reason for this..
Please let me know sirs..
best regards,
Kim
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You need to stir also or move the heater to different places in the drum. Convection of heat is (evidently) not sufficient.
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During chitin hydrolysis, non-crystalline glucosamine also obtained whether is it due to caramelisation. If anyone worked on that please give me some references
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Thank you Rumesh
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Omega 3 portion of fish oil is of importance for maintenance of vitality and protection of body organs esp. CVS and CNS with aging process. So my question is would omega 3 component of fish oil is better to be taken alone or with the other type of omega fractions of fish oil to gain the most nutritional and protective benefit?
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What you are looking for taking omega 3 is to compensate the w3/w6 ratio in your ingesta that use to be lower than expected un occidental countries due to the excess in the ingesta of w6. Anyway you need both in your diet 
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I need a method to determine RS in rum
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I agree with Bruna it wouldn't have an effect. Nevertheless, you could try with the DNS method, based on the determination of the reducing groups of each monosaccharide and the reducing ends of the chains of oligo- and polysaccharides present in the liquor samples. Reaction between 3,5- dinitrosalicylic (DNS) acid and samples is quantified by measuring absorbance at 530 nm reported by Wang et a. 2011 "High efficient conversion of cellulose to polyols with Ru/CNTs as a catalyst"
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Send paper if available
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Dear  Jaydipsinh
You 'll find a collection of thermo-physical properties of food  in the book
I. A. Tschubik and A. M. Maslow:
"Wärmephysikalische Konstanten von Lebensmitteln und Halbfabrikaten" 
(in English roughly: Physical Constants of Food and Semi-finished Products).
 VEB Fachbuchverlag Leipzig (Germany / former German Democratic Republic), 1973
This book is a German translation of a Russian original. Unfortunately, I do not speek Russian and I am not able to read Russian characters ... so I'm not able to give you the original title.
I don't know whether a German text is of help for you ... and if you can get the book at your University library. If you need help, please let me know. I might help you with a copy.
Regards from Switzerland.
Nikolaus
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As matter of fact, I've been working to produce Doogh (Drink of Iranian dairy products) which it probably could produce from whey instead of yoghurt.
Thanks.
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i am sorry, it was misunderstanding i thought that you may work with dough as i don't know what is Doogh mean??
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In fact, i'm looking for any slautherhouse that is applying lactic acid on beef carcasses surface.
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Los del IRTA quizá sepan decirte.
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Disruption of cell microstructure affects the quality of fruits and vegetables. So how does this microstructural changes occur with change in parameters such as temperature, moisture content during drying?
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