Food Analysis - Science topic

 I want to do the PV using spectrophotometric method. The problem is that linear curve of cumene hydroperoxide can not be able to obtain. Later, i find in some paper, chloroform is having high absorbance in blank reading. Chloroform with ethanol as preservatives is recommended. In another paper, it is mentioned about the modified method of Richards and Hultin (2002) along with the concentration range of cumene hydroperoxide. 

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.

We are evaluating our first ICP-QQQ for analysis of food samples (i.e. wine and oil together with vines and olives and thier leaves). We have narrowed it down to two models: AGILENT 8800 or

THERMO iCAP TQe. I would get some feedback from the owners, pros and cons and if they have compared the same brands before purchase.

best regards

Marco

The decline in agricultural production and exports in many countries is pushing up food prices. The scale of food shortages will increase in many countries and the risk of a food crisis is growing. More and more data confirms that after the recent pandemic economic crisis 2020, the growing economic crisis caused by high inflation, the developing energy crisis in 2023, there will also be a food crisis in many parts of the world. In the current 2022, a number of factors have simultaneously emerged that could lead to a food crisis and hunger in many countries of the world. These include the following factors:

1. the war in Ukraine (production and exports of cereals and other agricultural crops from Russia and Ukraine have fallen significantly).

2. Record heat, drought, forest and crop field fires in many parts of the world (in India, record heat reaching 50 ct. C in the shade; drought throughout the western states of the USA; in central and eastern Africa the worst drought in 40 years).

3. Flooding of farmland in China in 2021 (30 million acres of farmland under water. Chinese authorities have announced that the 2022 crop yield could be the lowest in the context of the previous few decades).

4. postcovid broken chains of international logistics and supplies.

5. in 2020, the Lebanese capital Beirut suffered a gigantic explosion at the port that destroyed all infrastructure, including huge grain silos.

For these and other reasons, the number of people in the world at risk of hunger has increased by 80 per cent in the last five years, from 108 million to 183 million people.

After Vladimir Putin ordered 200,000 Russian troops into Ukraine, the global food situation went from poor to bad. Especially this negative trend is developing in poor countries, where economies are underdeveloped and income levels of citizens are also low.

Before the war, Ukraine was the 5th economy in terms of global wheat exports, 3rd in barley exports, 3rd in maize exports and 1st in oilseed exports (e.g. sunflower). In Ukraine, areas of fertile chernozem extend as far as Manzuria. Before the war, Ukraine produced 9 per cent of the world's wheat, and together with Russia, this is now 30 per cent. Ukraine generated 20 per cent of the world's maize exports. By contrast, Ukraine's exports of sunflower oil account for as much as 75 per cent of the global share. Food exports from Ukraine are also estimated at 1/8 of all calories sold globally. Most of these exports before the war, i.e. before 24 February 2022, were loaded onto ships in Odessa and Novorossiysk and transported to the Middle East and elsewhere in the world. The war has created serious problems for food production and export in Ukraine. The Russians have blockaded the Black Sea ports with their Black Sea fleet.

In view of the above, I address the following question to the honourable community of scientists and researchers:

How can the scale of the development of the food crisis be reduced?

What is your opinion on this topic?

Please reply,

I invite you all to discuss,

Thank you very much,

Regards,

Dariusz Prokopowicz

Due to many different factors, a food crisis can develop in many countries. The international supply and supply logistics chains that were interrupted during the SARS-CoV-2 (Covid-19) coronavirus pandemic have not been fully rebuilt. Rising fuel prices are driving up the cost of transporting food products to shops. The decline in fertiliser production is also driving up the cost of producing crops. In addition, the war in Ukraine has resulted in a decline in cereal supplies to many countries. The lack of electricity has caused a decline in the production of nitrogenous fertilisers. This then caused a decrease in the production of CO2, which benefits producers of many types of food products. Many food product factories are raising the prices of their products due to increases in raw material, energy and fuel prices. Many production facilities are reducing the scale of production. There may be job cuts. Consumption is falling due to high inflation. If a downturn in the economy occurs in the next quarters, many companies may go out of business and unemployment will rise. In addition, periods of increasingly severe drought, more and more hot days and less and less rain and more and more frequent fires in many parts of the world are causing a significant drop in crop production in agriculture. On the other hand, further food crises may arise in the future in the long term, which will be the result of a global climate crisis developing on a multi-year scale.

In view of the above, I address the following question to the esteemed community of researchers and scientists:

What is your opinion on the subject?

What do you think about this topic?

Please reply,

I invite you all to discuss,

Thank you very much,

Regards,

Dariusz Prokopowicz

Like I would like to get help with the steps in writing a practical report

Regarding the above question.......

Thank you

For measuring somatic cells and analysing milk constituents

Does anyone know a protocol to remove/eliminate/precipitate tannins from aqueous extracts of plant leaves?

Thank you.

I am in search of methods of quantitative and qualitative estimation of cellulase in a food sample(biological sample)?

Can anyone suggest me a bioinformatics approach to identify a mutation if it is naturally occurred or created by genetic engineering. For GMO and food analysis it is required.

With a small team we are currently researching on nouvelle Jewish-Israeli cuisine as a worldwide trend and hence as a social-anthropological modern phenomenon. Your contribution could help analyze and describe a complex and ever changing food-culture.

Understanding processes that shape our cultures and identities is key.

Thank you.

Good Morning researcher, I'm a student currently on project to debitter the soy milk hydrosylates. But the problem is the soy milk hydrosylates is not bitter. So im asking if this protein content effect the bitterness? Im using papain enzyme to hydrolyse the soy milk, and how much concentration does it need to hydrolyse it?? Thank you!!

Hello people,

I'm using sigma's TDF-100A kit for the assay of total dietary fiber. However, it's taking a vary long time to filtrate the fibers after precipitation in ethanol. Sometimes the washing solvents just get stuck in the crucible and I cant finish the filtration . Does anyone have any tips to share about this procedure?

If you read the labels on food, you'll see the words "natural flavoring" or "artificial flavoring". The initial impression may be that the first must be good, while the second must be bad but if we look at what natural & artificial really mean in practice, most natural & artificial flavors are exactly the same chemical compounds, differing only by their source and both natural & artificial chemicals are or will be purified in a lab.

In some cases, natural flavoring may be more dangerous than artificial flavoring (e.g., natural flavor extracted from almonds can contain toxic cyanide but the artificial flavor has the taste but does not have cyanide).

Few years ago, my students prepared natural & artificial strawberry jams in a practical course. The taste of the artificial was judged to be better unanimously by the technician, my students & me.

Few years ago, a colleague's students made real strawberry ice cream & artificially- flavored strawberry ice cream. I tasted both & the second was more delicious, for me.

These two observations puzzled me. I know something about flavoring but I am not a full-fledged expert so I am asking to learn: Are natural flavorings really better & safer than the artificial counterparts? Is the public health at risk upon consuming foods & drinks with artificial flavors?

What are the common adulterants in commercial honey? how to identify pure honey and adulterated honey with the help of NMR spectroscopy? Is there any other technique to check purity of honey?

I used to notice in our food culture in Iraq that a person who suffers from anemia or loses blood is advised to eat celery with the spleen, and I did not know the reason until after my academic studies of plant pigments (chlorophyll) and the Similarity large between them and hemoclobin, as well as that the spleen is the cemetery of iron.

How can some customs and traditions be correct even though at the time of their spread there was no great scientific progress as is the case at the present time?

Please let me know about how to analyse pollen in honey in a simple and specified manner

In most of the food analysis procedures, before the chemical analysis of vegetables/foods are oven-dried at 50-60 centigrade temperature. Does it affect the nutrition content in the sample?

Thanks! Any help is appreciated!

For sustaining my PhD thesis I need to publish 1 or more articles with ISI impact factor (total ISI value 5). I have the experimental results from my previous job and I don't have the possibility to publish trough institution, so I have to publish them myself. The field is (electro)chemistry with aplication for food analysis (MSG). Do you know any journals with low costs for publishing an article (maxim 150 $) or even free?

I want to know the most important application of GC/MS in food analysis and the most common columns suitable for general applications of GC/MS.

Hi,

I've been reading around GC for use in food analysis (quality, taste, aromas) and was wondering if there any great benefit of combining FTIR and MS in one system.

I understand the complementary information from both methods on isomer structures for example. Recently, literature uses dedicated GC-MS and GC-FTIR. So, I was wondering if this is because:

1. FTIR spectra are rarely needed for general research.

2. System setup is so much simpler when separated that it's worth the money to get a dedicated system.

3. Combining the two is a hell of a task (synchronization?) and not worth any money.

4. Combining the two isn't effective (sampling speed, LOD, type of things)

I might be missing something important as I haven't worked with GC yet.

I found the topic quite interesting as a "pastime read", so I'd appreciate any views. Maybe somebody with experience from the 80s? From what I found it was quite a thing back then.

Thanks

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

Potassium Sorbate added to cheese with low pH due to the presence of lactic acid; does lactic acid act the same as HCL to convert Potassium Sorbate to Sorbic.

Also, potassium Sorbate added to brine ( saturated water with salt 10% at 4 C degrees)

How you think these conditions will affect the equilibrium between potassium Sorbate to Sorbic acid.

The problem in food industry labs they rely on outside labs to test and analyze samples for all out of ordinary tests and I've been trying to find a lab to analyze Potassium Sorbate separate from Sorbic acid but they only test Sorbate by HPLC which doesn't give an idea how much of each component is in that sample.

I am conducting a meta-analysis and most of my studies report values for bacterial analysis in CFU. However, I have one study which reports its microbial values in MPN. What should I do?

I'm planning to start with a project of a laboratory that makes microbiological analysis to food industry. I'm plan to buy some second-hand equipment to make less hard the initial investment. Is it recommended? Wich providers are recommended?

Rice is the seed of the grass species Oryza sativa (Asian rice) or Oryza glaberrima (African rice). As a cereal grain, it is the most widely consumed staple food for a large part of the world's human population, especially in Asia. It is the agricultural commodity with the third-highest worldwide production (rice, 741.5 million tonnes in 2014), after sugarcane (1.9 billion tonnes) and maize (1.0 billion tonnes).

I'm doing a study by using honey as my main treatment substance. The problem with honey is, honey collected from different sources have different physicochemical characteristic and its ingredient is also different. Does each honey sources need to undergo separate toxicity test? Human have consume honey for thousand of years and we can relatively say it is safe especially after rigorous standard food post-harvesting processes. 

I used Microwave Plasma-Atomic Emission Spectrometry (MP-AES) to analyse mineral content of various foods. How to calculate how much of a given mineral is in 100g?

I used 25g of food which has been ashed and treated with HCl, then turned into a solution of a total volume 100ml. Initial solution was too concentrated so I had to dilute it and I made a 1 in 100 dilution = 1ml of my initial solution + 99ml of deionised water.

How do I work out how much of a given mineral is in 100g of analysed food sample? For example, one of my results for Selenium from the MP-AES was 8.43 mg/L

Thank you for your help

Hello,

I am aware of FDA being the reference institution for food production control. However, I am not sure which guidance in particular defines the testing which are required to be performed?

Thanks,

Antonio

Food waste occurs due to over-production and managerial errors.

This because table sugar is extracted naturally from sugar cane or sugar beets and hydrolyzed to glucose and fructose and never could reach the body cells in its origin form. The hydrolysis process occurs in mouth, stomach and small intestine which the products of sucrose in body may be in a similar manner to that of honey and bread. In other words, sucrose is a carbohydrate that occurs naturally in every fruit and vegetable. But, why there is no similar propaganda to the not natural synthesized chemical candy such as aspartame and so on.

I hardly find a paper which involves free amino acid estimation. Instead what I get is total amino acid estimation using hydrolysis procedure. So I doubt there are free amino acids present in cereals. Please share your experience here if any.

Please all . I need to know how to calculate the spike samples for food analyses . I spiked the sample before microwave digestion ( in solid phase ) i spiked 5 ppb and i get instrument result of 35 ppb . How can we get recovery for that ?

Dear all. I have i food sample and i need to analyse lead in it . Should i choose lead 206 and lead 208 or only one is enough. If i choose the both how can i translate this in the calibration standards . Thank you

I watched a documentary, "Rotten", that explored the various methods of honey adulteration. The high demand for honey with the sharp decline in honeybees are a concern.

Seems such practice of honey adulteration is widely practiced.

As consumers, how can we know pure honey from altered ones?

Need brief answers

I also want to understand whether DNAFoil Test kit is specific for a particular food sample, i.e being targeted for a product. For instance; Having DNAFoil Pork test kit as well as DNAFoil Beef test kit.

Hi I'm trying to analyze insoluble, soluble dietary fiber in baking products using dietary fiber kit (Megazyme).

I'm wonder whether this dietary fiber kit method measure resistant starch as an insoluble dietary or not.

Greetings!

I'm tryingto validate an HPLC method for the determination of phenolic compounds in vegetable matrix. There are many international guidelines available which gives the parameters and criteria for method validation (ICH, FDA, etc.) but when it comes to vegetable matrix method validation, guidelines are not quite clear (many articles doesn't even mention which guideline they used to perform the validation). So my question is:

Is there any international guideline for HPLC method validation for vegetable analysis (food matrix) ?

I will appreciate every answer and recommendations

Thank you very much!

The result that i got is low fracturability. As I understand low fracturability indicates high crispness due to low forces needed to crack the material. However, I got confused when I found a literature that showing the result of fracturability and crispness result is moving in parallel. Hopefully, can get some clarification. Thank you!

Off-seasons vegetable offers the higher prices to the farmers. Instead of high price, people preferred off-season fruits and vegetables. It is a general perception that such fruits and vegetables are not good for health. There is any such studies proving the various negative health effects?

Hi I want to analyze the volatile compounds of crackers using HS-SPME-GC-MS.

I heard that people usually use both library and RI value to identify volatile compounds. I'm going to use n-alkane to calculate this RI value.But I have no idea how to inject this n-alkane standard. Do I need to use HS-SPME as well? Or analyze with direct injection?

And, as far as I know, this n-alkane is an external standard, so I do not need to add it to my sample. Is it right? Let me know if I'm wrong. I'm sorry to ask basic questions.

I was researching for debittering process on soy milk hydrosilate, and I'm using activated carbon to debitter it. I'm doing trial and error test and I can't find the correct method for debittering process. I'm using granulated activated carbon with comparison 0.5 - 1 gram per 1 gram protein on soy milk, and I just stir it together.

The process result are :

- Bitterness not decrease significantly

- The color of the milk is quite gray

- The taste of the milk is affected by the flavour of activated carbon

Any recommendatiom for the mash of the activated carbon, how to filter it, and how to decrease the bitterness??

Our pesticide standard mix will include at least 74 compounds. I would like to spike samples with 5 to 10 well characterized pesticides. Any advice?

I need a standart of 2-AP (2-acetyl-1-pyrroline) for analisis in GC/MS. Anyone ever synthesized this compound?

On using perkin elmer ICP-MS. The lead in food is analysed with two modes , the standard mode and helium mode . But the result was totally different as it was much lower in helium mode. So what result we can report and how we be confirmed ??

Dear all,

I am trying to understand the diet of different fish parasites using stable isotope analysis. I have indications (isospace) that some of them are feeding directly on the fish tissues, but others on other sources (not fish tissues). How do I correct C13 and N15 for fractionation in this case? Are you aware of studies and /or correction factors applied to fish parasites?

Best regards

Alessandro Manfrin

Dear all,

I am analysing the food environment of a case study, and I need data on the food store density (per capita and/or per surface area) of other cities and urban to compare my results with other contexts. Is there anybody who knows a database or a research study that collects this information?

Thanks in advance

Choongan Caralluma

Caralluma Tuberculata

Urdu: Chongan

English: Bitter Cress

Pushto: Pamankay

It is a wild plant used as a food. Its taste is bitter.

It is found in Africa, Saudi Arabia, India, Pakistan, Afghanistan and Southern Europe.

I can't find any interesting study showing such dependence reliably. Maybe someone know a interesting paper?

Dear Researchers,

In order to analyses the particle size of flour, except from the sieves method, what other methods are available and what is the preparation of the sample?

My Column is Shimadzu SHIM PACK VP-ODS (4.6 × 150mm x 5 µm) RP

and Mobile phase is 10% Methanol

Kindly suggest

Thanks in advance

I want to make some testing kit-like formalin for fruits, vegetables, fish, milk etc or carbide for fruits etc.

I used ICP-OES for mineral analysis in food samples. i digested 1g sample in 8ml of triacid mixture and made up volume to 100ml with dist.water. I got the ICP-OES values in ppm. I used 50ml for analysis. How to calculate dilution factor for this? which is diultion factor for this? Whether 8 ml acid or whole 100ml ? Whether we can represent the results using arbitary mass unit (g/100g). Read many references and didnot got clarity about this. Kindly provide your valuable suggestions. 

Is anyone aware of a referenced method other than (PCR/electrophoresis/elisa ) to detect GMO in foods and feed?

Hello Everyone

Laktan 900 seems to be a very promising device for quick milk analysis in field. Its portable and cost effective.

Can anyone explain the working principle of this device?

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.

Hey lovely community,

can anybody help me out here? A friend of mine is searching for some sources where the main methods for the determination of bacterial count in the field of cosmetics and food analysis are explained. Couldn´t find so far what she was searching for. Would be very happy for any help. 

Many thanks!

What is the most frequently used formula to determine sample size for analysis of food. Given scenarios are with known and unknown population size?

Can I do crude fibre estimation of a defatted sample which I have dried at 105 degrees C after defatting it?

Hello, I am looking to perform a colorimetric protein assay (Bradford/BCA etc.) to compare the protein content of different potato varieties, but I would like to use a different model protein besides BSA and gamma globulin to prepare my standard curve. Are there any plant-based proteins that can be used for this purpose? 

Also what criteria are needed to be fulfilled in order to select a non-established protein (i.e anything besides BSA) for use as a standard? Thank you!

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.

It is usually essential making artificial samples by blank matrix with standard substance added in method validation. When it comes to the situation that target analyte as endogenous substance always occurs in the matrix, for instance, the citrate in oranges, it is almost impossible to get the real blank. Is there any  solution either alternative validation experiment design or alternative blank? Standards or codexes adopted strategies  are best.

As per FSSAI / CODEX phosphoric acid (as P2O5) content in cocoa powder is maximum  2.5g / Kg

in my reach i am getting beyond the limit 1. alkalized(KOH) dark cocoa powder(ph :5.2 to 6.3) results are 16.80 g/kg,(method for detection IS: 14828:2000)

2. alkalized (sodium carbonate)cocoa powder (ph: 6.5 to 7) phosphoric acid result 19.78 g/ kg(Method for detection IS 14828: 2000)

3. Natural cocoa powder (without alkalization) phosphoric acid result 5.22g/100g (UV method for detecting phosphorus then converted to phosphoric acid by molecular weight )

As per FSSAI  & CODEX standards 3 samples getting phosphoric acid  result above the limit 

can you share the possibilities of  presence of the phosphoric acid  in cocoa powder 

The method which relevant to analysis of above mention sweeteners by using HPLC-UV/DVD

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 

Primarily the usage of XLD agar is for the detection of Salmonella species in food analysis. Some sources say that e.coli also can be detected by the presence of yellow colonies. Theoretically yellow colonies observed for the presence of other Enterobacteria which maybe also coliforms. Any suggestion for the testing methods  to justify this yellow colonies? Thank you. 

see above

I would like to determine hemagglutination activity in legumes.

In paper or techniques manual, 7.8 value is taken for calculation of TBARS (mg malonaldehdyde/kg sample). But no one is mentioned how this 7.8 value is considered for calculation. Can anyone enlighten me it properly? 

Hello everyone,

I am stuck on this question since last 2 days.. thought to share with you guys.. 

i want to know that what do you exactly mean by diet studies and if someone is planning to do it for a specific set of products then how it should be calculated..??

If you can provide me any relevant publications then it will be great help..

Thank You 

I need full procedure methods of AOAC for yoghurt Analysis can any body help me?

I try to quantify paraquat/diquat in potato using LC/MS similar to the attached method but using different LC column. I use standard in solvent with internal standard (IS) to correct for matrix effect (paraquat has enhancement). The issue is the response of the analytes and IS is not consistent in sample matrix so the number is way off (sometimes is too low, sometimes is too high). I injected the same blank matrix with analytes 5 times and response was not the same. The run is isocratic so the matrix of the first injection may show up in the second or even the third injection. The paper use matrix-matched standard with IS (which is over kill) and it may be necessary to do it. I e-mailed the authors but so far no response. any comments are welcome.

food chemistry 

fraying potato

degredation of acrylamide  

Please advise me the standard methods to estimate the shrimp allergen and also to identify the associated protein of shrimp allergen.

I have to evaluate yoghurt samples for six characters (i.e. Color, Appearance, Odour, Taste, Texture and Overall acceptability) using a 5 point hedonic scale. Can I use 5 samples at a time?