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The total mesophilic plate count is widely used as a broad indication of Microbiological quality, although it is unsuitable for this purpose in fermented foods sample, why is that?
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Hi Twana,
The total mesophilic plant count will be unsuitable in case of fermented food as there are chances of mesophilic contaminants active in the fermented food if kept in exposure to contamination or the result of poor quality control while the packaging David Sturm has answered nearly the exact same answer. It can also be understood by a condition that while the food sample has been a fermented product and the time the other mesophilic contaminant was inactive due to certain reason and with due course of time after a certain time limit the microbe dominating the fermented food might start producing metabolites that other contaminant can consume. Although microbe in the food sample present in its packaging it can be slow but while being the mesophilic and getting the nutrient from the plate itself it has a good chances of experiencing a better growth then in the food itself.
Hope this might clear your doubt,
Best Regards
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I would like to test a biological method of screening vegetables/fruits for the presence of pesticide residue. Since a biological agent is used, the extraction solvent should be non-toxic.
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QuEChERS sample preparation
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My project is on the production of a novel beer using non-traditional yeasts. At later stages, we are considering large scale production and commercialization.
The issue is, some of the yeast species that I am working on are not present in the Qualified Presumption of Safety (QPS) list of the European Food Safety Authority (EFSA), or in the Generally Recognized as Safe (GRAS) list of FDA. Although, there are articles and/or patents on their use for beer/wine production and they are present in IDF/EFFCA inventory of microbial food cultures.
The sources I found are a little confusing as I am not very familiar with this process.
My main question is, is having a QPS or GRAS status necessary for a species for their use in commercial production?
For a deeper understanding, my further questions are:
  • Is it the same for filtered beer, even if the microorganism will not be in the final product?
  • If we apply for QPS/GRAS, how long the process takes? - From my understanding, EFSA is updating their evaluation every 6 months, and their list every 3 years. Therefore, if I apply for a new species, the earliest possible approval would be in their next list?
  • Should we apply for QPS/GRAS for a new strain of a QPS/GRAS species if we want to commercialize?
  • If the new species belong to the same genus, would it help with the process? (For example, Lindnera jadinii is on the list, would it make it easier for Lindnera saturnus?)
  • Is the absence of toxic/harmful effects on the human, animal, environment is sufficient for this status, or are clinical studies required?
  • Would Anamorph/Teleomorph names of the same species in the list make any difference?
Thank you very much for all your help in advance.
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Do you have any information legislation about mycotoxin limitation acceptance in food for human and animals.
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Dear All,
I have problems with spoilage caused most likely by lactic acid bacteria in vegan sliced sausage. The product was stored at ~7°C in vacuum packaging and after three weeks it got yellow spots. Due to literature research I am pretty sure that it is Leuconostoc gelidum that causes these yellow spots.
I also had problems some months ago with slime after some weeks of storage and I think this was also caused by lactic acid bacteria. The problem in this case (pilot plant) is the recontamination of the product by the slicing process which is done manually.
Do you have any suggestion, which preservative agent works best against lactic acid bacteria or Leuconostoc gelidum in particular?
thanks,
Wolfgang
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.... of most bacteria, including food pathogens, spoilage bacteria, and the lactic acid bacteria used in vegetable fermentations, are readily destroyed by heating to 160°F (71°C), especially when the pH is low. Acid and low pH are also toxic to most bacteria. https://www.ars.usda.gov/ARSUserFiles/60701000/FoodSafetyPublications/p328.pdf
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The question is related to investigation of food poisonings in humans.
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According to Microbiology book by Mahon, Yersinia enterolitica it is mostly occur after ingestion of contaminated food, often pork and vacuum-packed deli meat, beef, lamb, chicken and possibly chocolate milk and water. It can also acquired from contact with household pets.
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Hi,
Under 9 CFR 430, establishments in Alternative 2b and 3 are required to sample food contact surfaces for Listeria monocytogenes or an indicator organism.
Source:
As part of this testing, are establishments expected to identify all possible food contact surfaces for sampling? I wonder how do you interpret the above rule.
Warm regards,
Chris
@foodsafety #foodsafety
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Implementation of environmental monitoring for Listeria monocytogenes should be based on risk assessment. There is no one program that fits for all. Looking for Listeria monocytogenes is of particular importance in the wet processing environment, which is conducive to Listeria growth. The monitoring program must look for the niches and harborage sites where there is a potential contamination of Listeria monocytogenes, this is not to be overlooked where RTE foods are exposed to the environment prior to to packaging and the packages foods are not subjected to a kill step. It is recommended to test product contact surfaces (for Listeria spp.) and occasionally testing finished product (for L. monocytogenes). This guidance might be helpful:
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Something besides the boar spermatozoan test? Thank you!
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by PCR
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Specifically for Rapid EC, Rapid Salmonella, Columbia blood agar, MYP, TSA, and XLD. Can it still grow? If so, what color and zone of inhibition?
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Ok, let me try...
On Columbia blood agar (with defibrinated blood incorporated after sterilization of the base medium) Listeria monocytogenes will grow and will give also a clear β-haemolysis reaction.
On TSA growth of the bacterium is obvious, though not so abundant (i.e. small colourless colonies and slow growth on the agar plate). For this to occur, 0.6% yeast extract should be added, thus making TSAYE, which corresponds to the preffered general purpose medium for L. monocytogenes. In general, yeast extract seems to be an important ingredient in the media used for Lm, since its use is suggested also by ISO 11290 in blood agar.
On XLD Lm will not grow, I can tell you that. I came up with that mistake once...
For the other culture media you mention, I can't tell.
Regards!
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What different between DPPH and ABTS assays when it comes to AOA determination?
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Any one who can elaborate the question
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Thankyou Jasim Al-Saadi and Carole C Tranchant for your kind expertise regarding the subject.
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We are taking up a work on milk from peri-urban areas of Guwahati city. Although there are some literature on detection of M. bovis in milk samples, I am interested on application of molecular based techniques as well as other rapid methods. How far is it possible to detect M. bovis in milk by PCR? Other than PCR, is there any sensitive and specific rapid test for detection of M. bovis in milk samples?I shall be very happy to have the answers for food safety. 
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We are taking up a work on milk from peri-urban areas of Guwahati city. Although there are some literature on detection of M. bovisin milk samples, I am interested on application of molecular based techniques as well as other rapid methods. How far is it possible to detect M. bovis in milk by PCR? Other than PCR, is there any sensitive and specific rapid test for detection of M. bovisin milk samples?I shall be very happy to have the answers for food safety. 
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Hello
Unfortunately, fresh fruits last few days/weeks before being spoiled in the refrigerator.
That spoilage is due to air-borne mold species such as Aspergillus, Cladosporium, botrytis and Penicillium.
How can we identify mold fungal species (apart from microscope) ??
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Best way to identify mold/fungi accurately is by DNA analysis which can be relatively easy to perform using Polymerase Chain Reaction (PCR) techniques. The rRNA/rDNA sequences of fungal samples are commonly amplified using PCR and sent for DNA sequencing. I normally use universal primers such as the ITS1 and ITS4 for identification of fungal samples.
If you are not familiar with PCR techniques, the general guideline is:
1. Isolation of pure fungal sample on a suitable medium
2. Extraction of genomic DNA
3. Performing PCR amplification of sample using the chosen ITS primer
4. Sending PCR products for DNA sequencing
5. DNA sequence obtain can be analysed using online softwares such as BLAST by NCBI
You can refer to this publication for more info:
Hope this helps! All the best!
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I’m trying to create LB growth medium (1% Tryptone, 0.5% Yeast Extract, 0.5% NaCl and 0.3% agar) with different water activity using PEG200.
Any suggestions on what concentration of PEG200 will create water activity of 0.95 and 0.97.
Also, has anyone measured water activity of LB?
Thank you.
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You'll need to use Raoults Law to predict the effect of solutes on water activity depression. The Aw calculation needs to include all solutes (I see that you have 0.5% salt, which will have some effect. Have used Propylene Glycol in food systems and managed to get down to 0.8 without too much problem.
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Consequent to some food-borne incidents in recent years, there have been significant increase in public health concern and decrease in consumer confidence. Despite significant advances in detection tools, regulations, monitoring and consumer education on food safety, reports of food borne illness outbreaks continue to increase. Within the supply chain which is increasingly becoming more complex in the globalized market, adulteration (unintentional or intentional) is the key food safety issue. Increase in imports of food/processed food items due to cost concerns, availability and consumer demand for diverse food products also provide chances for food contamination/adulteration. Regulatory bodies are comforting with major food safety issues including changes in our food production and supply, environmental changes leading to food contamination, new and emerging bacteria, toxins, and antibiotic resistance and consumer preferences and habits leading to increase in imported foods. At this juncture, what should be the effective strategies to address the emerging challenges to provide safe, healthy, nutritious and sustainable produced food to the world's population?
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I agree with dear Dr Debra Sharon Ferdinand-James
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I am working on natural antimicrobial  food additives, and I want to examine the ability of chitosan as an antimicrobial agent
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Dear Taghreed Hafez,
You may be able to produce water soluble chitosan by yourself!
Vahid
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Someone has information on fermentation with abnormal development of volatile acids in the rehydration of stockfish?
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Nice
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I will inoculate the P.Phosphoreum to fish. I could not decide on the stock culture media and method for determination. Can anyone help me please?
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by LAMP vageli.
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What are the microbial standards for ready-to-eat and ready-to-reconstitute products in India.
I have developed RTE and RTR product using cereal and chicken ingredients.
Kind regards!
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I think you can refer to FSSAI standards in India. They are available on the website of FSSAI (http://www.fssai.gov.in/home/food-standards/regulations/food-products-standards.html). You may find related product (often not exact what you look for).
All the best
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I wish to send strains of Salmonella enterica and Campylobacter jejuni from Japan to the United States, and I am wondering if US customers require an import permit.
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Yes, you will need permits. Probably from both CDC and USDA/APHIS as these organisms are human and livestock pathogens. 
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First I want to freeze presumptive Listeria, and then I want to detect presumptive  Listeria monocytogenes with PCR.
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As a member of the Dutch Commission on Genetic Modification I am interested in how the opportunities of gene editing for sustainable production of healthy food supply are affected by regulatory regimes and I am interested in studies on this specific relationship.
As you state, how gene editing is / will be regulated is an important factor in failure/success of biofortification. As far as I can see there is three possibilities:
1. Current GMO regulation will apply to gene editing in plants (in Europe and other parts of the world)
2. Gene editing of plants will be deregulated
3. The Canadian regulatory systems applies, i.e. products of gene editing with new characteristics have to be assessed.
Moreover, regulation regarding health claims may apply to products of gene editing.
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I am Hernan Ceballos and do conventional breeding in cassava. We have succeeded increasing carotenoids in cassava roots through conventional breeding. Although I could envision genetic transformation and gene editing competing technologies with my own area of expertise, I have always supported them. We need to solve the problems of millions of people by whatever means. It should not be a matter of competition between technologies, nor about regulatory issues. Dr. Potrykus team made a breakthrough way back with golden rice. It made the point of bioforitification on one hand, and the power of genetic transformation on the other. Yet about half a million children turn blind each year in Africa because of vitamin A deficiency. It is a shame for mankind that somebody, seating comfortably in an office (mostly) in Europe, thinks he/she is paying a service by preventing GOOD technologies reaching these children. The regulations related to the release of GMOs condemn them to blindness (and eventual death) and condemn me to eat tomatoes full of pesticides (as it is often the case in many developing countries). Regulation has taken away MY RIGHT to eat a Bt-tomato... So I totally support Dr. Portykus´statement about regulation. Hopefully, gene editing will relax things a bit and easy the way for common sense to prevail. Hernan
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I am looking at different flours in baked goods such as biscuits and breads. Baking time has been a fixed factor in me methodology and I have noticed that longer baking times have increased the protein levels of the final products. When looking into this, it seems most people report a decrease in protein content following thermal treatments. Can anyone suggest a reason for this or some literature that might of use. 
Thank you in advance. 
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Do you express your protein content on dry matter basis or on product basis?
Longer baking may increase the dry matter content, so protein in dry matter is for me the best value.
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There is a campaign in London at the moment to reduce food waste.   This is overwhelmingly focussed on fruit, vegetables, cakes, bread, etc.    People are terrified of redistributing meat products, due to the deep-rooted belief that meat is the origin of the most frequent and most severe food poisoning outbreaks.  This might have been true in the past (see The Torah), but is this the case nowadays?    I realize strong theoretical arguments can be made against individual meat products, but what is the overall epidemiological picture?  Should there be a blanket ban against recirculating meat near its sell-by date?
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Dear Anthony,
I think that Lucas stated a good point. In my oppinion when discussing the danger that meat can cause in respect to the human health we should first be aware that meat is very wide term which beside fresh meat also include various meat products, some of them with very long shelf life e.g. dry/cured produtcs like hams (Prosciutto di Parma, Jamon Iberico etc.). So, in my oppinion it is difficult to make  general statements on meat as the reservoir of microbiological threat. Although I can agree that food borne dissease epidemia outbreaks are frequently caused by certain meats, esspecially poultry as Mirande has shown, one should also be aware that wide veriaty of meat preservation techniques exists; from simple freezing and other thermal treatments to different methods of moist control and direct microbial inhibition such as use of certain chemical preservatives. 
Instead of a blanekt ban, I would suggest special care when dealing with different meats and meat products, and use of differnt treatments that can be applied in order to preserve or prolong the for which a product remains usable.
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I am working on cold active lipases and having trouble in purifying the enzyme due to very high degree of aggregation. I have tried breaking the aggregates using several detergents such as CHAPS, Tweens, Triton X100, NP40, Brij-35, SDS, etc but no success till now. The high molecular weight aggregates are not able to move in to PAGE and remain stuck at the interface of stacking and resolving gel. Find the attached images of SDS and native PAGE showing protein bands at the top of gel. Any suggestions please..
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What, precisely, is your aim? Do you just want to see the protein in the gel (e.g., for quantification), or do you want to purify the active enzyme (e.g., for kinetic measurements or industrial use)?
In the former case, I'd start with 7 M urea, 2 M thiourea, 10 mM DTT and 1%SDS. 
In the latter case detergents with fat-like structure (lyso-lipids, fatty acids, FOS-choline, LysoFos, neopentenyl glycols) may be able to to solubilise functional protein. In any case, I'd start with a careful literature search. A day in the library can save you months in the lab!
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There are two origins of phytase : microbial phytase EC 3.1.3.8 and plant phytase EC 3.1.3.26. I want to know if the microbial phytase from Aspergillus niger is GRAS ( Generally Recommended As Safe) or not. Thanks
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phytase It is an enzyme and passes several steps of purification ..Definitely  Aspergillus niger is GRAS 
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Hi,
I made a single strength juice of red and white grapes using concentrated juice (clarified).
They have same brix value, which is 11, but different total acidity (0.1366 for white, 0.1661 for red)
The white one is much sweeter than the red, when tasted, probably due to the low acid content. But pH of the red (3.88) was higher than the one of white (3.66) though the red has more acids. 
So I'm wondering what makes the red grapes to have higher pH....
Do the anthocyanins in the red grape increase pH? Or other reasons??? Please help!  :"(
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Dear Sel,
Just to complete the answers you already received.You should to don't forget that winemakers are always trying to pick-up white grapes with a low acidity level (ph around 3,3) instead for red wines they  pick-up grapes in function of the total polyphenols amount and not only using acidity level as a key quality indicator. Even if the acidity still to be a key quality indicator. That is one reason why white wines have almost "always" lower pH than red wines. To sum up : white grapes pick up : aromas+acidity firstly ; to pick up red grapes : polyphenols concentration (anthocyanins+tanins) firstly.
Hope this helps.
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we analyzed milk samples of same batch and packed at same date and same time (both samples in original packaging and sealed)
but the results obtained are not understandable
one sample has High TPC and Coliform whereas the other has lowTota Plate Count and negative coliform.
there is no testing error and no cross contamination.
can any one explain the factors
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Microbiology is not chemistry, therefore you can not expect "uniform" results when sampling raw foods. In the case of raw milk, particularly if it is not filtered and homogeneous (by industrial treatment or by integral sample preparation) results could differ. In particular fat content may change counts drastically, and fat tends to go at the top of your container. In addition depending on the hygiene of the industrial container (or machinery) from where you got the samples, there could be pieces of biofilm from the container or equipment walls. We do not know the containers or equipment from where you got the samples, and how actually you took and prepared them; but wild differences seems to point to the lack of uniformity of the milk and/ or the presence of biofilm particles (e.g. lack of hygiene).       
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in my recent work I need to sterilize a chicken drumsticks samples to inoculate them later with specific E coli strain then treat them with chemicals and recover them after treatment, and the later step I will study the effect of my treatments to the strain I used. the tricky part is how can I be sure that I'm recovering the same isolate if the samples were not sterile 100% ?.
In fact I already tested some methods for sterilization I used dipping in alcohol up to 3 minutes and still have some E Coli appear in the plates, then I sent some chicken drumsticks for Gamma radiation. the issue with the radiation is I still have a high microorganisms populations around log 5-6 growing in TSA media at 30 C for 72 hours. but in the other hand there is no E coli can be detected in VRBA-MUG media at 37 C for 24 hours.
the question is should I be satisfied with the fact that Radiation possibly eliminate all the E coli background in the samples ? or the presence of other microorganisms which they can be mold yeast and other Enterobacteriaceae in TSA is problematic ?. people here think this load will affect the attachment of the E coli strain I want to use.
is radiation suppose to eradicate all microorganisms because in my reading I find it doesn't in fact it eliminate bacteria while spore forming and mold reduced only and there is temperature , time and dose factors can interfere with the results. also the radiation dose I used was 10 kGy for 17 hours which is higher than what really recommended and found in references.
Finally , is it really possible to sterilize chicken samples for experimental purpose? and if it is possible is there any better method rather that radiation?
Thanks in advance 
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You can cook the meat so that all the bacteria are dead and ensure its sterile. Then go for doping with your Ecoli and use chemicals as you suggest as preservative.
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How do we expect the current trend of climate change to impact on food safety?
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I think another factor that has not been discussed yet is an indirect impact.  Crop failures/yield reductions will lead to crop price rises.  This will make affected crops more attractive targets for adulteration.  We have already observed these practices e.g. with spices being adulterated with nut derivatives leading to food safety issues. 
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I ordered some bacteria from DSMZ. One of them is freeze dried ampule and the other is actively growing culture. I would like to learn, should I use the bacteria strains as soon as I receive them or I can store them in optimum storage conditions in a few days?
Because I have to inoculate the bacteria in different days and in different product. Are these freeze dried ampoules and actively growing culture disposable or I can sustain the culture during a few days?
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Dear Chin,
As I know you should subculture your strains as soon as recieve them. Or you can ask where you get them. 
Bests
ilknur
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i use low molecular weight to check antifungal activity 
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Dear Maliha,
Low molecular weight chitosan is very potent anti-fungal substance. The following references will help you to know the details:
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Are the limits for Enterococcus spp. in food for use as hygiene indicators?
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Unfortunately there is no "official"/""regulatry" agreement in destroying of D-Streptococci. USDA has a 7D prescription
In Europe we use mostly the data of Prof. Reichert (Lemgo) D=2,95 min, z=10°C, Tref=70°C and 12D destroy.Microbiologically the Streptococci can be divided into a less and a more resistant group. The difference between the groups is about 2x, e.g. the  12 D destroy of the resistant group would require 24D destroy for the less resistant grouip. My experience from industrial measurements is that the more resistant strains and variant are not present or their number is very low in the bacterial population of the raw material because the Reichert data (less resistant group) and 12D destroy enough for inactivation and no need stronger thermal process because there no health claims and public health problems against the cooked product. Furthermore the experiance based thermal stopping condition survive today as well ( so many hours as kg of product for large and irragular shaped product, so many mm in diameter so many mins in cooking time, reaching a definite core temperature around 70°C) . On the contrary strict microbial prescription is valid in the EU legislation. Unfortunately the hot smoking and cooking chambers display ambient temperature, core temperture relative humidity but not the equivalent pasturising unit. THese have to be calclated separately (sorry in middle levele company 100-150 curves in a day) or compnies has to buy an auxiliary software to do it.(they are available through the machine producer or through the temperature measuring device producer (ELLAB, Ecklund, Ebro etc.). This optional is not a standard in the price offers.
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From an analysis I conducted, I found no significant difference between levels of contamination among carcasses at different slaughter stages. However, other recommended hygiene indicators such as Total Aerobic Counts and Enterobacteriaceae significantly differed. Is it safe to conclude for now that Enterococci is not a reliable hygiene indicator for raw meat?
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i found for food irradiation uses gamma  rays ,x rays ,electron beam part of accelerator machine i would i ask about any another particle could use in irradiation food such as proton or electron 
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Please, correct me! What did I say that is wrong?
I said it might be possible to use other particles, but without having worked in the food-irradiation industry, I can only come from the particle acceleration side of the argument.
So, gamma rays, x-rays, and electron beams are currently used. Why don't they use other methods? Other than activating your foodstuffs, let's think of this from the business end since the food industry is a business.
X-rays are created in an X-ray machine. The food is exposed to these X-rays. Simple.
Gamma rays are created through a radioactive source, such as cobalt-60. The food is then exposed to the gamma rays created by the source. This is also simple, and less power-intensive than the use of X-rays.
Then we have electron beams. These are created by applying an EM field, and the electrons are accelerated to near-c almost instantly. This is also simple, and cheap. However, the electrons are unable to penetrate as deeply as the other two methods.
So, I do correct myself. I said electrons are the only ones that make sense. However, what I MEANT was that, compared to particles such as neutrons or protons, they are much easier and more cost-effective. This is not true of gamma and x-rays, as they are also simple and cost effective.
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I would like to find studies of the possibility of growth and reproduction in low pH conditions of some Сlostridia and Bacillus strains, capable of causing disease, food poisoning or allergies. Thanks in advance for any information!
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Hi Hoshi, thank you! The second article is close to what I'm looking for
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When I detect spores, are there any specific tests? Will the presence of spores in a food product show colonies in TPC? If yes how to differentiate the two
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When you perform the total plate count you will be able to observe the growth of fungus as well as bacteria.
Once there is growth on the plate you can perform different staining techniques and after microscopic examination you can perform confirmatory spore staining 
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Food origin isolates exhibit imipenem resistance so I wondered about the reasons?
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Lucinda - I would like to see the article you mentioned you were going to attach.  In the U.S. it has been well documented that antibiotics have been over prescribed, and still are.  Not completing a prescription is also a problem, and we should not forget that besides agriculture there is also some misuse for pets.
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I meant another method rather than using sorbitol MacConkey agar?
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You can use pcr to detect the stx 1and 2 and other genes for attaching and effacing 
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I would like to measure the particle size of pea globulins in a Malvern Mastersizer and the refractive index is requiered.
Thank you!
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You won't get such direct reports. You must first do the basic characterisations like MW etcAnd then from any data bases for proteins you may get some data.
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Is there any method to find out if Aflatoxin B1+BSA conjugate is degraded ? I have a stock of 1mg/ml stored in -20 degree and would like to cross check if anything is wrong with the stock. 
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Are you concerned about the aflatoxin or the conjugate? As indicated above the aflatoxin itself is quite stable. The protein (BSA) and  (stability of)  the conjugate might be a different story.
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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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We have many problems with the cocoa exported in USA and Canada, about the fragments of insects and any biological material found in the cocoa from Côte d'Ivoire. For that, we hope to do first analyses of the cocoa food and other food in place before exportation, and we need a standard and approved international and scientific methodology for doing a Filth test. We need any information and document for doing practical Filth test (Material and techniques  for sampling, extraction, identification and analyses).
Best Regards
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the test is done by macro and microscopic methods as far as I know. the application is done in flour and cereals product as this type of food product is exposed to a such contamination due to bad storage or bad    hygiene  practice. However the attached file may help   
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Cordyceps Militaris was inoculated on the rice liquid culture medium. The pH value of liquid medium first increased and then decreased. I want to know the reason for the change of pH value. Why the pH change? Waiting for your answer. Thanks!
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The decrease in pH may be due to production of organic acids. I just think the increase in pH observed after the decrease may be due to some of these acids (eg lactic acid) are metabolized (act as substrate) to support microbial growth. Because this reduces the concentration of the acid hence an increase in pH. To  ascertain this you need to measure titratable acidity (TA) too and see how that changes along the course of microbial growth.
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I tested viability of L. plaatarum NCIMB 8826 at simulated gastric fluids. My SGF was prepared by using 2 g NaCl, 3 g of Pepsin and 7 mL of conc, HCl. Distilled water was then added to get 1 L. After that pH was adjusted to 2 by 1 M NaOH. SGF was sterilized by a syringe filter (0.2 um). One mL of culture was added into SGF and incubate for 2 h.
After incubation, I did dilution in saline solutions and used pour plate method.
I and my labmate repeated in couple times. The cell counts were higher that 6 log CUF/mL. The results reported by other papers showed that the cells could not survive after 2 h at pH 2. 
Can anyone suggest what happen with my result or what I did wrong?   
Thank you in advance. 
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Please, make sure the inoculation size  of bacteria and isolation  source must be from  Human sources 
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I will appreciate explanation for conditions that must be fulfilled for a salmonella isolate to be categorised as a new serovar. I recently sent some isolates of salmonella for serotyping and the results came back with a few categorised as 'untypable'; while some are categorised as just 'salmonella enterica' without serovar names and the rest (majority) with various serovar names attached. I wonder if the 'untypable' isolates and/or others ('salmonella enterica' without serovar names) are probable new serovars!
With thanks
kayode
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Yes the serotype of C. muytjensii strain 51329 is Cmuy O:2.  See
Jarvis, K.G., Yan, Q.Q., Grim, C.J., Power, K.A., Franco, A.A., Hu, L., Gopinath, G., Sathyamoorthy, V., Kotewicz, M.L., Kothary, M.H., Lee, C., Sadowski, J., Fanning,S., Tall, B.D., 2013. Identification and characterization of five new molecular serogroups of Cronobacter spp. Foodborne Path.Dis. 10, 343-352.
 
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Hello, 
in my knowledge, filamentous fungi usually grow slower than yeast. Does anyone has the same opinion? Please include references.
Thank you
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Excellent Stephane, Thank you so much. you have answered my question perfectly. 
For your information, I am developing a specific method for marine yeast isolation that is why there are yeast and mold together.
The number of yeast cells and mold is not known to me but both in the seawater sample.
I used the YPD broth as enrich media as  explained before for 2 days then used the culture to inoculate a fresh media for 2 days then inoculate a fresh media for another 2 days 
but now I am writing a research article with full details on the isolation method, characterization  and identification of marine yeast. 
so many thinks a gain and if you have supporting reference for what you explained will be very much appreciated 
Abdelrahman
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I analyzed two chocolate samples for S. aureus using 3M Staph Express. After 24 hours my plates were filled with blue-green and black colonies, so I used the Express Disk. After 1-3 hours my plates had these large yellowish zones. For what I've read in the 3M interpretation guide, the zones have to be pink to be considered S. aureus, so I don't know what to make out of said result. I have linked a picture of the plates, hope it's clear enough.
Thanks in advance.
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Dear  Javier Amores.
Although the plates used are specific to S aureus, Staphylococcus can also grow other, but should be reported as unquantifiable or not found in the lowest dilution that did.
Annex a photo where you can see colonies of S aureus and other Staphylococcus. They are samples of cheese
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Summary
Tofu industry in Indonesia which has been dominated by local’s small entrepreneur, and very identical with the use of formalin (formaldehyde), a dangerous substance for food additive. Since 1940s, the dependency is severe due to the drastic gap of productivity between the usage and no usage of formalin, since there has been no food additive alternative for the case of increasing the yield and shelf life of tofu.
Tofu producers are now enjoying a new hope from the emergence of newly develop natural preservative: a lactic acid bacteria culture that is able to give the equal yield and shelf life compared to formalin. However, there has been no regulation for such product in Indonesia, thus the application of the product will bring numerous problems to the producers because the “formalin mafia”s are around and will likely use the regulation gap to dispute and extort the producers.
A team of food scientists (including my self and Prof. Winarno) and an elder from a tofu producer community himself have been striving to register the new preservative to the appropriate regulation, whether it is already exist or needs to be made as new. The team itself has no interest regarding the product, but only in the purpose of putting an end to the use of formalin in Indonesia. Several laboratory tests have been conducted with the following results:
1. Contains active Lactobacillus spp cultures
2. Inhibits the growth of tofu-deteriorating/rotting microbes (directly retrieved from the tofu)
3. Has the pH of 4
4. Contains only 0.39% of lactic acid
thus brings assumptions of bacteriocin and organic acid (gives low pH) as the cause of its preservative activity.
Bottomline
Regardless the confidentiality and research limitations, We wonder anyone has any reference(s) for regulation, analysis methods, or anything that might be useful to the issue.
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If yes, will the product (curd) has all properties of Probiotic like Yakult?
Probiotics are very important for goof digestion. 
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Hi Suneel. I agree with the comments of Ng Seah Young. I guess that if you want to make a curd is because you are thinking in some kind of cheese with probiotics characteristics. L. casei Shirota's growth kinetics parameters are essential in this because some microorganisms are slow fermenters and are added in a belated stage of the process. As a starter you need a quick fermenter which acidifies the milk fast and coagulates the casein. My advice for you is to search for this data although is real what Jacob Simons says about Yakult. I think there are better options for what you want.
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I am trying to test for the efficacy of essential oils as antimicrobials against Listeria and Salmonella in soft cheese. I will be working with inoculum levels of 100cfu/ml and 10000cfu/ml because they are levels of detection. my question is how I can achieve these two levels of inoculum accurately.
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Dear Bruno, I recomend you M26-A, M07-A8 and M100_S21  NCCLS - CLSI protocols.
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The integrity of Romanian food products is a basic prerequisite to ensure consumer trust, and it has direct effects on stimulating internal and external consumption.
At the national level there is no recognized and validated definition for food integrity – the literature presents[1]:
·      food integrity as being the perfect state of food products, which assures the agrifood chain’ participants that the food products are safe, authentic and qualitative.
·      food safety: ensures that the food products will not have any negative effects on the health of the final consumers, when being cooked or consumed.
·      food quality represents the characteristics of the food products, which make them acceptable to the consumer. It refers to the sensorial characteristics, like size, shape, color, taste, flavor, gloss, consistency, texture, as well as to the physical, chemical and microbiologic characteristics.
If issues related to food safety and the quality of food products are regulated both by the European legislation[2] and by the national legislation,[3] for authenticity of agrifood products there is no regulated framework: there is no validated definition, and there are no conditions, features, procedures, contraventions, sanction, etc.
This shortcoming might have been favoring potential counterfeiting, adulteration of agrifood products throughout the entire production-marketing chain. In this context, inadequate and incomplete regulation, which could ensure a more favorable environment, has contributed to the problem of unauthentic, counterfeited food products on the market, with multiple effects on both consumers and the state. However, the lack of regulation is not the problem per se, as there are other causes that will be explained in the next sections and the regulatory failure, not solving the real causes of the problem, has made the issue more acute over time.
Food authenticity represents the certain, undeniable origin, compliance with standards and regulations in force and the elements inscribed on the label accompanying the food products. The interest to demonstrate the authenticity of a food product arises due to several reasons, among which eliminating unfair competition, eliminating tax evasion due to deliberate omission to declare certain ingredients on the label, ensuring food safety. The criteria that define the authenticity of a food product are numerous and vary from one product to another, the most important being: geographical origin, botanical or animal origin (species / breed from which the raw material originates), the category of raw material (conventional, organic, ecologic, and genetically modified), processing and preservation technology, and production year.
[1] Bulancea, M.,Râpeanu,G.(2009), Authentication and identification of counterfeited food products, “Editura didactică și pedagogică” Publishing House R.A, Bucharest
[2] Reg. 882/2004, Reg. 852/2004, Reg. 853/2004, Reg. 178/2002, Reg. 1151/2012, Reg. 668/2014, Reg. 1221/2008, and others.
[3] Law 150/2004, Law 145/2014, MARD Order 724/2013, MARD Order 394/2014, Order 560/2006, Emergency Ordinance 97/2001, Emergency Ordinance 12/2006, Order 392/2013, Order 438/2002, Order 485/2004, Order 387/2002, Order 173/2013, Order 230/2002, and others.
The integrity of Romanian food products is a basic prerequisite to ensure consumer trust, and it has direct effects on stimulating internal and external consumption.
At the national level there is no recognized and validated definition for food integrity – the literature presents[]:
·      food integrity as being the perfect state of food products, which assures the agrifood chain’ participants that the food products are safe, authentic and qualitative.
·      food safety: ensures that the food products will not have any negative effects on the health of the final consumers, when being cooked or consumed.
·      food quality represents the characteristics of the food products, which make them acceptable to the consumer. It refers to the sensorial characteristics, like size, shape, color, taste, flavor, gloss, consistency, texture, as well as to the physical, chemical and microbiologic characteristics.
If issues related to food safety and the quality of food products are regulated both by the European legislation[] and by the national legislation,[] for authenticity of agrifood products there is no regulated framework: there is no validated definition, and there are no conditions, features, procedures, contraventions, sanction, etc.
This shortcoming might have been favoring potential counterfeiting, adulteration of agrifood products throughout the entire production-marketing chain. In this context, inadequate and incomplete regulation, which could ensure a more favorable environment, has contributed to the problem of unauthentic, counterfeited food products on the market, with multiple effects on both consumers and the state. However, the lack of regulation is not the problem per se, as there are other causes that will be explained in the next sections and the regulatory failure, not solving the real causes of the problem, has made the issue more acute over time.
Food authenticity represents the certain, undeniable origin, compliance with standards and regulations in force and the elements inscribed on the label accompanying the food products. The interest to demonstrate the authenticity of a food product arises due to several reasons, among which eliminating unfair competition, eliminating tax evasion due to deliberate omission to declare certain ingredients on the label, ensuring food safety. The criteria that define the authenticity of a food product are numerous and vary from one product to another, the most important being: geographical origin, botanical or animal origin (species / breed from which the raw material originates), the category of raw material (conventional, organic, ecologic, and genetically modified), processing and preservation technology, and production year.
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Hi,
The report published by Prof. Chris Elliott from Belfast Queen's University on the Horsegate scandal in the EU tackles adulteration, food fraud  and integrity in a lot of detail.
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Isolation Medium: Nutrient Agar (pH 7.2)
Isolated from: Singara (a light snack sold in a roadside shop)
Colony Characters: Shape- Circular, Pigmentation- Off White, Elevation- Convex, Margin- Entire, Surface- Smooth, Optical Characters- Opaque, Colony Diameter- 3 mm. 
Gram reaction: Positive
Aerobic in nature. 
Resistant to most antibiotics viz. Chloramphenicol , Neomycin, Doxycyclin, Erythromycin, Gentamycin, Kanamycin etc.
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This is difficult to say, simply from these characteristics. If you have the possibility, prepare the 16S-RNA and sequence that. This is a highly conserved molecule, which will tell the taxonomy of your strain. Otherwise, go more systematically through a microbial identification protocol, which can be found in Bergeys Manual and other source.
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I would like to simulate the liquid media used for releasing test of my encapsulated particles. The prospective system is the lactic acid fermented food products. Which kind of buffer (which have to contain the lactic acid and at pH 4.5) is preferred?
If I use the other buffer systems like citrate-phosphate or citrate-sodium citrate buffers and add lactic acid into these buffers, does it represent the lactic acid containing-food liquid? or should I use lactic acid-sodium lactate buffer instead of them? Which one is the best represented lactic acid-containing food liquid system?
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I inoculated E.coli O104 in 6 whole lettuce (iceberg) leaves to see the survibality. I want to do 3 days interval sampling. Now I cannot understand whether  I can keep individual leave in separate bag/ any other container as lettuce leaves are big size or all  6 leaves in same bag /any other container for better sampling. if anybody know about this, please answer me.
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Whether you treat an individual leaf as a replication or treatment, I suggest under all conditions you put one inoculated leaf in one bag/container for an unbiased sampling.
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Could 2,6x 10^15 be possible? This result refers to research on raw fish (and fruits) after 8 days incubation at room temperature.
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 As far as I know , the  bacterial cell densities in the human colon of 1011-1012 are the highest reported for any known ecosystem. In my studies, the level of spoilage bacteria have never exceeded 1010 CFU per gram of spoiled fish.
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I am wondering if there is a Quechers method for Ocratoxin A in coffee? Is it best to use 100% acetonitrile or have a mixture using mixture of Acetonitrile and methonal (1:1). Aslo if i would like to clean the extract up using dSPE do i have be concerned with mycotoxins bonding to the psa? If i increase the starting strenght of the acid concentration will this allow for me to use psa in the clean up with out the mycotoxins bonding to it?  
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See the following article,
Roasting coffee beans (coffea arabica) artificially contaminated with ochratoxin A strongly reduces the analytical ochratoxin A content but not the genotoxic effects. Current Topics in Toxicology. Vol.9, 75 - 80, 2013
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Hello!
I´m trying to extract total bacterial DNA from sausage samples using a protocol for sample preparation (removing proteins, lipids etc.) followed by a commercial DNA isolation kit.
After that I checked the quality and quantity of DNA with Qubit and gel electrophoresis, and did 16S rRNA and genus specific PCRs but I still don´t know if the extracted DNA contains any animal DNA and if it does, how much.
Any ideas?
Thanks!
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Before doing the PCR, you could separate prokaryotic from eukaryotic DNA  by the presence of methylated CpG motifs (usually not methylated in prokaryotic DNA, whereas the majority of them are methylated in eukaryotic DNA). Some column kits able to bind methylated CpG motifs does exist.
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The story is:
I am doing the inhibition on mycotoxin-producing fungi by lactic acid bacteria. Last year, I did some tests, and found a lactic acid bacterium (later identified as Lactobacillus plantarum by checking 16S rDNA) could inhibit the growth of Aspergillus flavus which was known for producing aflatoxin B1.
However, since Feb 2015, new regulations from CDC, TW started to re-class some fungi (including A. flavus NRRL 6432, BCRC 30003 I used) as the BioSafety level 2 cultures, and should be operated in the BSL2 lab (our lab is BSL1, and I hope it can be upgraded to BLS2 for more research).
I’m curious, how those mycotoxin-producing fungi are regulated in different countries?
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In Chile there is a regulation por "Aspergillus" (in general, i.e. all species) in BSL2
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I would like to conduct an experiment to prove the bacteria which we have used in our experiment having a good proteolytic system. Initially we have used casein hydrolysis method on agar plates, but the results are not satisfactory to conclude the experiment. So, please share your experience that may helpful to my experimenet. Thanks     
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Without a doubt, OPA (o-phthalaldeyhyde) is the best method for the assesment of proteolytic activity in dairy produts. 
Church F. C., H. E. Swaisgood, D. H. Porter and G. L. Castinagni. 1983. Spectrophotometric assay using o-phaldialdehyde for determination of proteolysis in milk and isolated milk proteins. J. Dairy Sc. 66:1219-1227.
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I'm working analyzing new treatments to eliminate pathogen flora in food such as Listeria, but we have a problem: We use a strain control of Listeria innocua but we found other bacterial species can grow in Palcam and Oxford agar (supplemented with antibiotics), possibly other species of Bacillus Catalase + , Gram + and oxidase - , giving us a false positive. Somebody have some idea ? The matrix analyzed are complex ( dairy products).
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See attached paper. It appears that many more species can grow on PALCAM and ALOA
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Dear Friends, 
I am doing the work analysis of  Dithiocarbamate in rice by reference EU SRM method SnCl2/HCl hydrolysis method. I have some observation here
1). Dithiocarbamate determine as CS2 release after  acid hydrolysis.
2). DTCs are the group of some compound (Thiram, Ferbam,  Maneb, Mancozeb, Propineb, Ziram, Zineb, Metiram, Nabam.) 
3) All DTCs released CS2 after acid hydrolysis.
But some time I want to analysis DTCs But I have only Thiram, Maneb, Zineb and Mancozeb. than how Can analysed All DTCs?
Same if we wanna analysed only single DTC as Thiram than How Can determine thiram only from group of DTCs?
Please suggest your valuable comments.
Thanks & Regards,
Rakesh Kumar Sondhiya 
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You'd better find the  precipitation or color of CS2 by chemical reaction, then you can detect it.
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aflatoxin contaminated food reported as canceriogenic products,andthis but altof constrain in importa and export of agricultural food products.sperggilus fung is the main producer of this toxic proteins, however spergilus density incresed in contaminated un healthy ecological soil.is there any relation beteween the density of this micro organisms?as an example in groundnuts farms , what is the role of rizobactor in minimizing or preventing aflatoxin in these ecological areas ?
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could you give more details on itis interaction?
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I want to use SEM or other microscopy method to visualize the spectral organization of these two bacteria cultured together, however, they are both gram negative and rod-shaped. Is there any other method to differentiate them apart ? 
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I think if you are simply trying to apply a microscopic approach to look at your cultures then atomic force microscopy (AFM) might be a good choice, certainly over SEM since it can image sample under (near) physiological condition (under fluid, or maybe in the culture medium) and obtain images with similar or even better resolution than SEM. AFM sample preparation is relatively simple and it can prevent artifacts caused by some traditional EM sample prep techniques, which are BTW relatively harsh. For the experiment set-up you might want to start with image the two cultures separately to obtain information such as dimension and surface morphology of each cell line. You might even be able to discover some special surface features on each cell lines that can serve as marks in later experiments. Then you can image the co-cultured cells and look for the spectral organization. Of course there is no guarantee that this approach will work but you never know until you try it out.
BTW, for sample preparation, in the literature there are many studies using AFM to image E.coli, you may find some information that could help you in those papers.
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I am currently doing a study on the antimicrobial compounds in spices and will welcome any help with recent studies especially on toxicity issues associated with the antimicrobial compounds in spices. I have some materials from journals but will welcome any further help.
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Toxicity for using spices as a whole in cooking would be negligible - but if you talk of the active ingrediants separately and isolate them they are definately upto a certain extent - toxic - again the question is toxic against whom?
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As I asked before about Escherichia coli regarding tween 20 utilization and got very useful answers, now I wish to construct a model of different substrate utilization scheme for Salmonella spp.
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It has been reported that some strains of bacteria especially the Salmonella enter the viable but nonculturable state (VBNC) when they encounter environmental stresses, such as low temperatures, oligotrophic conditions, infiltration press, and biocides including heavy metals and ultraviolet radiation. VBNC bacteria are organisms that fail to grow and develop colonies on media, but their metabolic activity capabilities indicate that they are still alive. Add 3% Tween 20 or 1% catalase enabled cells to make it become culturable again, with resuscitation times of 48 h and 24 h, respectively.
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If i used (Amicon  10,000 MWCO) to concentrate the bacteriocin from MRS broth, the bacteriocin will be at the top part near to the filter or it will be in the bottom container? and what is the time, speed and temperature for centrifugation?
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It will depend on the size of your bacteriocin.  My guess is that most bacteriocins will NOT be concentrated in this manner as most of the ones from lactic acid bacteria (that have relevance as food pathogen inhibitors) are small molecules, around 2,000-3,500 mol. wgt, so unless they complex with some other molecules, you won't be concentrating them.  But that is OK, because you will be 'cleaning up' the sample from most of the larger molecules that will be retained, but I would suspect the bacteriocins would elute through the filter and be in the filtrate.  You can easily determine the amount retained/lost by doing activity titer before, and after Centricon ultrafiltration.  If you have a vacuum dryer, one easy way would be to use Sep-Pak C18 cartridges hooked up to a syringe.....pass the bacteriocin-containing culture broth through that....everything will bind to the C18 matrix (eluate should look clear; cartridge will appear 'brown' by retained media proteins), and then using step-wise 10-ml rinses pushed through the cartridge by way of a syringe....wash with Isopropanol:  0% (water), 10%, 20%, 30%, 40%, 50%, 60%, 100%......dry these down with a vacuum concentrator if available and resuspend with water/buffer of your choosing.  You will likely find that much of the 'brown' protein content elutes somewhere in the 10-20% fractions and hydrophobic bacteriocin molecules in the 30-50% fractions. A simple way to use hydrophobic nature of these molecules to your advantage in quasi-purification.  Similarly, another way would be ammonium sulfate fractionation....stirring different media samples with different levels of ammonium sulfate saturation to selectively precipitate bacteriocins (0% ammonium sulfate, 20%, 40%, 60%), centrifuge, decant, resuspend pellet with water/buffer and check to see which percent cutoff may selectively precipitate your bacteriocin peptide. If you produce your bacteriocin in MRS broth, ammonium sulfate will cause the Tween 80 to flocculate at the surface upon centrifugation and you may want to collect that as I often found that is where the bacteriocin is found....in that surface flocculated film that can actually be scooped off the top (and resuspend that in water).  Good luck....these procedures can be found in the literature.
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Im looking for proof of concept papers in this particular matter as we are trying to do an experimental approach for a competition and want to know the state-of-the-art technologies that are being used. I would appreciate any thoughts, help or guidance. Thank you in advance for your time and precious time.
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I am not sure what you mean by 'synthetic phages'?  Do you mean, bacteriophages that are harvested manually from bacteria or recombinant DNA-based bacteriophages?  Presuming the former, the use of bacteriophages as a food preservative faces a difficult challenge in that the lytic bacteriophages that are generated on a particular host are subject to restriction modification by that host whereby the phage DNA is modified and not considered 'foreign' and not degraded. That is the main problem....the recovered bacteriophage work best on that one host strain, likely showing a very high efficiency of plaquing (EOP). The problem is, as a food preservative, the antimicrobial ( i.e., bacteriophage) should work equally well on all targeted strains, such as E. coli O157:H7 for instance.  If it is propagated on 1 strain of E. coli O157:H7, it should work on all E. coli O157:H7 strains and not just work well on the 1 strain it was propagated on. Otherwise it renders the preservative with little or no effect in practical commercial application.  Aside from that problem, is the problem with 'inhibition kinetics'....bacteriophage are relatively large particles (compared to acid chemical antimicrobial molecules like lactic acid), they are finite in number and therefore as they interact with the food matrix, they are 'tittered out of solution' so to speak and the amount remaining is that much less, and also they require a direct contact and injection of their DNA into the targeted host bacteria, so it would likely only have application on the surface of a food, not after it is mixed into a food (like ground beef) where the food matrix may bind and complex with bacteriophage particles, or coat/cover/conceal targeted bacteria. So even on the surface of a food, what kind of titer is required in solution to provide coverage of the surface with bacteriophage no further apart from each other than the length of a bacterial cell?....since once they land on a surface, they are not planktonic anymore and are somewhat fixed in position. Good luck.
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Lately, I have been trying to understand the mechanism behind bacterial spores and their germination after their exposure to heat (if they are present in food). Although there are several scientific papers about the effects of heat treatment on germination rate and outgrowth (mainly of Bacillus spores), it is difficult to squeeze out practical information necessary to evaluate the risk for the end consumer.
The question is how much time bacterial spores need to outgrow back to vegetative state once a food (e.g. soup, meatballs, poultry meat, etc.) in which they are present is exposed to heat which destroys vegetative bacterial cells and then temperature drops back to the range favourable for their outgrowth.
If I summarize my literature findings so far it seems that bacterial spores become quite unpredictable once exposed to heat and that the time needed to develop back to an exponentially growing cell varies considerably even among the same bacteria. However I am not particularly familiar with factors by which the variation is caused.
I would like to open an argued discussion about this issue among different researchers.
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Hi! Have you had a look at the paper in the link below? It might be helpful.
Good luck!
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Nowadays dietary bacteriophage has widely used in poultry. It may create negative health impact on Human health. 
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It is important to remember that we ingest thousand of bacteriophages every day with no harm to human health.  In fact, there is interesting evidence of symbiosis between animal and bacteriophages, ( http://www.nature.com/news/viruses-in-the-gut-protect-from-infection-1.13023) which makes sense if we consider we (humans) have evolve with the daily presence of bacteriophages.   
Bacteriophages are the most abundant organism in the biosphere, and FDA granted the GRAS (generally recognized as safe) status to those commercialized for use in food production
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There is lots of residue after combine harvesting, decomposition of crop residue may provide a good option to manage the rice-wheat residue.
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Hi Nikhil 
Its better to go for trichoderma sp., Pluerotus sp. along with dung slurry it enhances the decomposition rate and it takes  maximum of 3-4 months.
Thank you
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We tried the method using a multiple leaching out of phenolics via several transfer on liquid MS with shaking without any success. Although we have no contamination, all the peaces are brown and no callus were formed.
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Add some antioxidant and 2,4,5-T or heavy amount of 2,4-D
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Sensory evaluation for food products
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What precisely do you want to do? Hedonic or quantitative/descriptive sensory analysis? They demand totally different strategies. There are fairly good handbooks and even normalized methods for jury training for quantitative descriptive sensory analysis.
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zeolites are wide used as additives in feed. But not nanozeolites. I do not know neither if such is a product of processing naural zeolites or it is artificially obtained 
Thank you
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Regarding the organo-zeolites, Peter lego from UK has done some work in that direction.The followimh is the citation of the article.
The role of clinoptilolite in organo-zeolitic-soil systems used for
phytoremediation. Science of the Total Environment 363 (2006) 1–10
It may throw more light on this aspect. In india we are trying for organo-zeolites for enhanicng the use efficiency of organic manures. A report was presented at ASA symposium during 2012. 
I have reproduced the abstract below.
Zeolites Regulate Nitrogen Release From Manure-Amended Soil.
See more from this Division: S08 Nutrient Management & Soil & Plant Analysis
See more from this Session: N Fertilizer Sources and N Use Efficiency: I
Tuesday, October 23, 2012: 9:05 AM
Duke Energy Convention Center, Room 211, Level 2
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Kulasekaran Ramesh, Indian Institute of Soil Science, Bhopal, India and Khandakar Islam, Soil, Water, and Bioenergy Resources, The Ohio State University, Piketon, OH
Manure-zeolite amendment of soil has recently been evolved as a novel approach to minimize reactive nitrogen formation and loss from agricultural fields. Zeolites are nanoporous secondary minerals having a high selectivity for cations especially ammonium ion which could be used for slow release of nutrients through organo-zeolite mixture concept. To study the effects of zeolite on regulating nitrogen release, a lab incubation study using dairy manure mixed with naturally mined zeolite (such as Clinoptilolite) was conducted at the Ohio State University South Centers at Piketon, USA during August and September of 2011. Zeolite and manure treatments were: Manure at 50-g oven-dried equivalent (M50); Zeolite + Manure at 1:5 ratio (ZM1:5), ZM1:10, ZM1:15, ZM1:20 and ZM1:30, respectively mixed with soil and replicated 6 times. The zeolite-manure amended soil in different treatment combinations were incubated at room temperature (~25 0C) for 7 days. The replicated samples of zeolite-manure treatments were taken every day over a period of 7 days and ammonium and nitrate concentration was measured calorimetrically. Results showed that the ZM1:15 had steadily and consistently release ammonium with a non-linear (parabolic) dynamics over time.
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Can enterobacter sp. be used as a probiotic?
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Hello, I think that there are many research about this area of interest.
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Can F. fujikuroi cause any disease or be pathogenic to other crops besides rice?
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Fusarium fujikuroi has not been found in any other species to the best of my knowledge. It has a closely related species F. proliferatum, which has many hosts from cultivated species. These two species have been found to interbreed and produce progeny. However, they have their specific hosts. Yes, Fusarium fujikuroi is pathogenic to rice and results in bakane disease.