Food Safety Culture

Since I started writing food safety plans, I have been interested in looking at recalls and seeing how a food safety plan could have prevented the recall. Additionally, I like to think about how the food safety plan would need to be updated now there has been a recall for a particular product or ingredient.

For example, today there is a recall of Ritz crackers due to Salmonella in the whey powder which is an ingredient. We don’t currently know who the whey powder supplier and manufacturer are as that has not been released to the public. However, as Mondelēz Global LLC, the food manufacturer who owns Ritz brands, is following Food Safety and Modernization Act (FSMA) standards for supply chain rules, they certainly do. As part of the supply chain controls, they would have guarantees of quality and safety standards, which would include providing a product being free of pathogens, including Salmonella.

What is whey? Remember the nursery rhyme? The curds and whey that Little Miss Muffet was eating on her tuffet is what happens when acid added to milk. You can do this at home by adding vinegar or lemon juice to milk. The milk separates into a lumpy clump solid portion and a liquid. The curds form as the insoluble milk proteins such as casein bind together with the milk fat. The liquid part is whey which contains the water soluble parts of milk including non-casein proteins as well as small amount of milk sugar (aka lactose) and minerals (Dairy Processing Handbook). Commercial whey is a dairy byproduct from cheese production.

Salmonella being present in whey powder is unexpected as milk, in the USA, is typically pasteurized before cheese production and after being separated from the curds, the water is removed first by ultra-filtration and then by drying. Since finding out that their whey powder was contaminated with Salmonella, the processor, and most likely probably FDA and other inspectors, will be looking to see if pasteurization and/or drying were sufficient to be processing preventive controls. They will also be checking their environmental monitoring and sanitation standards to find out where the Salmonella happened and prevent it from happening again. As well as contacting the FDA, they will also be contacting other companies that they provided their whey powder to as part of their recall process.

Fortunately, there is a small chance of Ritz crackers actually causing an outbreak of Salmonella as the crackers are cooked during manufacturing. The manufacturer will have this listed as a process preventive control in their food safety plan and, after this recall, if they haven’t done this before they will be validating the baking step to ensure that it is sufficient to kill Salmonella. This means they don’t have to rely on their suppliers for food safety.

Interested in food safety plans and how to use them to improve your food processing? Leave a comment below.

Food Ways: Sea biscuits

OLDEST SHIP BISCUIT. This specimen appears at the Maritime Museum in Kronborg Castle, Elsinore, Denmark. The biscuit dates from 1852. Image: Paul A. Cziko (https://en.wikipedia.org/wiki/Hardtack#/media/File:Oldest_ship_biscuit_Kronborg_DK_cropped.jpg)

It has been an interesting journey doing the research on sea biscuits and I am sure there is more information I haven’t found doing a quick internet search. Sea biscuits are the Navy’s equivalent of hardtack, which is a relatively new comer as it was named by the 19th Century American army. Given the simple recipe (mix flour and salt with water to make a dough, roll out into patties, bake in a medium oven for 30 min at least twice) these biscuits were probably around in prehistoric times and still surviving in some hidden cave somewhere. These biscuits last longer than flour as they have a lower moisture content and water activity. One disadvantage is that sea biscuits will absorb moisture if the humidity increases. This was a problem when Royal Navy ships first traveled in the tropics.

When I travel, even on short journeys, I am in the habit of carrying some food and water with me. Travel delays on trains and planes have been part of my travel experience and I prefer to know I have food rather than hope I can buy something if necessary.  Travelers need food that has a long shelf-life, is robust, safe to eat, and calorie/nutrient dense. Many travelers’ food is dried as removing the moisture  extends the shelf life by essentially making the food inedible to bacteria. While removing water has the advantage of stopping bacterial growth, it doesn’t always give us a food that is robust and could stand up to the rigors of travel. There have been a number of times I have reached into my rucksack for a cookie/biscuit and found crumbs. Not the snack I was hoping for!

The sea biscuit has more in common with Terry Pratchett’s Dwarf’s rock cakes than any modern cookie or cracker. So robust that, typically sea biscuits need to soaked overnight or smashed with a hammer or rock to able to eat it. Sea biscuits are the original cracker that was crumbled into New England chowder, probably because that was the only way the biscuits could be eaten. The British navy used to bake/dry their biscuits 4 times. So if you think biscotti are hard to eat without dunking, double the force needed to bite into a sea biscuit and book that trip to a dentist to replace your teeth. They were so hard that apparently an American civil war soldier wrote a letter on the side of a hardtack and mailed it with the address on the other side and it survived in the mail without any protection. No wonder British soldiers were envious of American food rations in World War 2.

In the process of making sea biscuits you knead the flour and water together. This allows for gluten formation and most of the recipes have a 2:1 ratio of flour to water which is perfect for gluten formation. Gluten is the protein that gives bread its springy texture and the network of gluten stays in place once heating is complete which means that bread keeps its structure after baking. While soft bread goes stale very quickly due to the retrogradation of starch, the starch in hardtack is probably all retrograded before leaving the oven. An interesting question would be to find out how much starch granules hydrate and swell in making of sea biscuits. Is enough for the starch molecules to gelatinize? Perhaps the water is removed too quickly for gelation and retrogradation occurs very quickly with little rearrangement of the starch molecules. (Confused – see my post on starch here!)

If you want to make your own sea biscuits there are lots of recipes online due to reenactors and survivalists wanting a food that is traditional and/or last a long time. They are also popular in Hawai’i and Alaska. Personally I would prefer water biscuits or Scottish oatcakes carefully wrapped than a food that is hard to eat. Trail mix would be more desirable still. However, if a zombie apocalypse is ever threatened, I know what I could bake to help my long term survival.

References

All references visited on 29 January 2018

1. https://en.wikipedia.org/wiki/Hardtack background
2. https://www.wikihow.com/Make-Hardtack recipes
3. http://www.survivalnewsonline.com/index.php/2012/02/hardtack-a-great-survival-food-stock/ recipe
4. http://cookit.e2bn.org/historycookbook/904-hardtack-ships-biscuits.html recipe
5. http://www.gone-ta-pott.com/hard_tack_sea_biscuits.html recipe and history
6. https://youtu.be/FyjcJUGuFVg video, history and recipe
7. https://reclaimingtheloaf.wordpress.com/2012/03/01/biscuits/ history
8. http://www.foodtimeline.org/foodcookies.html#shipsbiscuit and http://www.foodtimeline.org/foodcookies.html#hardtack history
9. http://www.menshealth-questions.net/royalnavalmuseum.org/info_sheet_ship_biscuit.htm history
10. http://militaryhistorynow.com/2014/07/11/hard-to-swallow-a-brief-history-of-hardtack-and-ships-biscuit-2/ history
11. https://www.rmg.co.uk/discover/explore/ships-biscuit history
12. http://www.janeausten.co.uk/ships-biscuit/ history

 

Tasty Tuesday: Sugar Chemistry

I really should just sent you to Exploratorium which has an excellent section on sugar chemistry, but sugar chemistry is so cool, that I have share it with you myself.  In fact sugar chemistry is so interesting that it supports a whole sector of the food industry.  I am, of course, talking about candy.  Food Scientists typically divide the candy industry into chocolate and non-chocolate candy and most of the non-chocolate candy is made from different forms of sucrose.

If you remember sugar is the common name for sucrose, which has the very confusing chemical name of β-D-fructofuranosyl-α-D-glucopyranoside which is a fancy way of saying that it is made up of glucose and fructose.  In this post, I will interchange the words sugar and sucrose, but in chemistry sugar refers to saccharides which  are considered to be small carbohydrates.

The most important property of sucrose is its high solubility over a wide temperature range.  The different sugar candies are made by heating a sugar-water solution, as the heating time increases water evaporates.  This increases the sugar concentration and the temperature of the solution increases.  The temperature of the solution is dependent on sugar concentration:

Effect of Sucrose Concentration on Temperature

Candy technologists not only control the sugar concentration by heating the sugar-water mixture to a predetermined temperature, they also control the final physical arrangement of the sugar molecules by the other ingredients added and by the way they treat the sugar-water mixture while it is cooling. This determines whether the solution sets in a crystalline form or not.  The non-crystalline form is also known as amorphous.  Thus sugar candies are divided into crystalline and amorphous.

Crystalline candies include fudges, fondant and rock candies. Amorphous candies include cotton candy, hard candy and brittles, where the sucrose has been set into a glass, and caramel and taffy, which are chewy rather than hard.

References

For Figure:

Wikipedia Candy#Sugar Stages

Harold McGee On Food and Cooking 2nd Edition p681

Non-Enzymatic Browning Introduction 2

Food tastes best when browned.

Food in always complex unless you are studying something quite simple such as a beverage with few ingredients (vitamin water, anyone?).  Even sucrose has a complex chemistry, more of which I will share in a future post.  So individual NEB reactions cannot be isolated in food.  Quite often intermediates and products from one reaction become intermediates in another reaction, especially in the Maillard reaction. Thus, most food chemistry textbooks use Non-Enzymatic Browning (NEB) as synonymous with the Maillard reaction. However, the other NEB reaction cause browning in food without the use of enzymes.

Both caramelization and lipid oxidation cause browning in certain foods, i.e. sugar-based and fried foods, respectively. Ascorbic acid degradation is significant in food with a low pH (high acidity) especially in citrus juices.  The reaction of flavanoids is important in highly colored foods as the colorful anthocyanins degrade and lose their color.  The reaction of flavanoids may also be important in soy protein, but less because of a color change and more due to a lose of isoflavones.

NEB Intro Part 1

Non Enzymatic Browning

My major interest in food chemistry is how food changes during processing and storage.  I am especially interested in how color changes take place.  The reactions I am interested in are called Non Enzymatic Browning reactions to differentiate them from the browning that occurs when you cut an apple or banana, which involves an enzyme.

Non enzymatic browning (NEB, non enzymic browning) reactions are the most important reactions in food, and, no, I am not biased.   Just image the aroma of melting chocolate, freshly baked bread or  a roasting leg of lamb, the golden color of a croissant, the dark amber color of a well brewed beer; caramels, toast.  These are all caused NEB reactions.

There are five different NEB reactions and I intend over the next few months to write about each of them:

1. Caramelization – browning of sugar, especially sucrose
2. Lipid Oxidation – the oxidation of fats and oils; including rancidity
3. Break down of flavonoids – highly c0lored compounds can also lose their color
4. Degradation of ascorbic acid (Vitamin C) – AsA is unstable even without oxygen
5. The Maillard Reaction –  reaction between carbonyl compounds and amino acids

Numbers (3) and (4) are not typically on a list of NEB reactions, but I did my thesis on ascorbic acid browning and it definitely goes brown without oxygen and without enzymes.  The degradation of flavonoids is one I have added and came to me in flash of inspiration when at a conference.  I am sharing it with you now, so this is new even though I had the idea three or four years ago.

More later…

Food Labeling

The March issue of Food Technology arrived and as always I turned to the last page, which is Perspectives*. This month Joe Regenstein has a very good comment about labeling and hiding information from the consumer is hurting the industry.  As he says:

The irony is that the activist community has had much more success in attacking the food industry for not labeling products than it really has had in convincing consumers that the technology is bad for them.

He goes on to protest about the misleading labeling, that really has no meaning:

And finally, what about all those terms we’re sticking on our labels (and in our advertising) that are sometimes justified but just as often plainly misleading?  For example: free range, natural, local. When these words are misused, we  not only cheapen the words,  but we cheapen the entire food industry.

So get with the act, food industry folks and tell what is really in our food.

*It is online too, but as a pdf file

Simple Sugars: Fructose, glucose and sucrose

Glucose, fructose, sucrose

Simple sugars are carbohydrates. Glucose and fructose are monosaccharides and sucrose is a disaccharide of the two combined with a bond.  Glucose and fructose have the same molecular formula (C₆H₁₂O₆) but glucose has a six member ring and fructose has a five member ring structure.

Fructose is known as the fruit sugar as its make source in the diet is fruits and vegetables. Honey is also a good source.

Glucose is known as grape sugar, blood sugar or corn sugar as these are its riches sources. Listed in food ingredients as dextrose.

Sucrose is the sugar we know as sugar or table sugar. Typically extracted as cane or beet sugar. If sucrose is treated with acid or heat, it hydrolyzes to form glucose and fructose.  This mixture of sucrose, glucose and fructose is also called invert sugar.

Nutritionally, these sugars are the same as they all provide 4 Cal/g. This is true for starch and other digestible carbohydrates too. Of the three sugars, fructose is the sweetest and glucose the least sweet, so typically less fructose can be used than table sugar (sucrose) – if sucrose has a sweetness of one, fructose is 1.7 and glucose 0.74

Fructose is more soluble than other sugars and hard to crystallize because it is more hygroscopic and holds onto water stronger than the others. This means that fructose can be used to extend the shelf life of baked products more than other sugars.

Wikipedia has lots information on sugars, including information on the three I am interested in fructose, glucose and sucrose.

Molecular Gastronomy is Part of Food Science

In a recent issue of Food Technology, the magazine for IFT members, Hervé This responds to the suggestion that molecular gastronomy is part culinary art and part science. He gives a very good summary of the differences between cookery/culinary, food science and food technology:

“Cooking is a technique (sometimes an art) and the objective is to make food.”

“On the other hand, molecular gastronomy is a science. It is performed in a laboratory.”

“Furthermore, science is not technology. Thus, applied science cannot exist. Application involves technology (from techne, doing, and logos, study). When examining mechanisms of phenomena, the goal is not to apply knowledge (application), but rather to produce it.”

He admits that he himself had problems during his thesis of separating out science from technology but he states very strongly that molecular gastronomy is science and molecular cooking is using the results from molecular gastronomy to create new food items or improve old ones. This’ Ph.D. thesis, on Physical Chemistry of Materials, was entitled Molecular and Physical Gastronomy or the equivalent in French.

The confusion between the science, art and technology of food is present in food science. That there does not appear to be a final definition of molecular gastronomy adds to this confusion, especially as chefs have taken over this term, rather than using This’ preferred Molecular Cooking. Khymos gives a good summary of the different definitions.

I do have problems with the fact that Molecular Gastronomy is so trendy and considered to be the saving of the world’s food supply.  [So I exaggerate? What’s the problem?] Many articles about Molecular Gastronomy and the restaurants that practice molecular cookery appear to have never heard of food science.  So I appreciated the fact that This states that molecular gastronomy is part of food science but I struggle to place it within the traditional subject areas of food science.  It overlaps mostly with food chemistry.  At least This’ part of Molecular Gastronomy is heavily physical chemistry based.  The research undertaken is more directly relevant to cooking and culinary arts than much of food chemistry.  For example, my research on the Maillard reaction has few direct practical applications, unless you are willing to mix amino acids and sugars together in your kitchen.  I still would not recommend eating the results of my research.

Within the article he gives an excellent summary of what science is – the idea of testing a hypothesis to give new information which increases our knowledge of a system.   I might even use some of these ideas for teaching.

References

Hervé This Molecular Gastronomy vs. Molecular Cooking Food Technology December 2008 (PDF)

Tasty Tuesday Science Snippet: Flavor Boosters

In the last issue of New Scientist (issue 2671; 30 Aug 08) there is an article (p22) in the technology section about molecules we can add to food that will enhance the flavor.  These molecules are flavorless themselves but increase the sweetness or saltiness of the food.  There are also molecules that will block the bitter taste of foods such as grapefruit.

These molecules are being developed by testing them against cell lines of taste receptors.  These receptors have been altered to glow flourescent green when responding to the taste in question.  These cell lines have also been useful in furthering sensory research – finding new taste receptors for compounds such as calcium chloride.

The cell lines are obviously not as good as the human tongue and can only respond to the taste that they are programmed for, typically sweet, salt, sour, bitter or umami.  Hence, when a flavor enhancer has been developed, shown to be safe for consumption, it has to go through a human sensory trial.

My concerns with flavor enhancers are several:

1) We get habituated to levels of flavor. So adding a sweet flavor enhancer may make us used to a high level of sweet tastes.  This is already true in the US, where food is much sweeter than that found in Europe.

2) This is pandering to the American preference of bland tasting food. In the article they were looking for bitter blockers for the after taste of soy but Asians and I (and probably many other vegetarians) do not find soy bitter.  Do people really dislike the idea of strong tastes so much, what about sweet and sour sauces?

3) I would prefer to see companies using more natural ingredients, especially herbs. Surely these new compounds are no cheaper than herbs?  I cook without adding any salt but I use a lot of herbs.  My Dad, who typically adds salt to everything does not do this to food I have cooked.  The herbs make up for the absence of salt.  Admittedly if I did use salt I could reduce the amount of herbs added to get the same flavor effect as salt enhances flavors.

Berries and Cancer

Dig those blackberries from last summer. Any excuse to reuse my photos! We all know we should be stuffing our faces with lots of fruits and veggies, but what is the evidence and which ones are the best?

In a recent article (1), Seeram reviewed the evidence that berries prevent cancer. This review was a little frustrating to follow, and I started wondering if it was a rewritten introduction to a grant application. For an article published in the Journal of Ag. and Food Chem., I personally could have done with a better overview. Some of the detail, while may be necessary in a cancer journal, lost me without careful concentration and then I lost myself in the acronyms. You may realize this from the discussion below. To be fair, they did explain quite a bit of the science and the subject knowledge might be all over the place with different researchers studying different berries and cancers.

In the USA, commonly consumed berries include blackberries, black and red raspberries, blueberries, cranberries, and strawberries. The active ingredients in berries includes Vitamins A, C, E and folic acid; calcuim and selenium; phytosterols; and phenolic molecules such as anthocyanins, flavonols and tannins.

So how good are berries at preventing and reversing cancer?

In vitro studies, with cell lines, have shown that berry phenolics in addition to being potent antioxidants, they also:

“[…]exhibit anti-inflammatory properties, are able to induce carcinogen detoxification (phase-II) enzymes, and modulate subcellular signaling pathways of cancer proliferation, apoptosis and tumor angiogenesis […].”

Coo. That sounds good, but as I am not a cancer researcher the details of the reviewed studies were difficult for me to follow. Raspberry, cranberry and lowbush blueberry juices showed the strongest inhibition of cell growth, which is good as we do not want cancer cells to grow. A red raspberry extract treated so it went through conditions that mimicked the digestive system decreased the number of colon cancer cells and protected against DNA damage induced by hydrogen peroxide. Blueberries induced apoptosis (cell death) of cancer cells and may influence prostate cancer cells [I assumed to the good]. Cranberry extracts inhibited the growth of human breast cancer.

Animal studies showed that rats fed berries and fruit juices showed a significant reduction in AOM-induced aberrant crypt foci, which is a leading indicator of colon cancer. AOM is azoxymethane and acts as a carcinogen to trigger colon cancer in rats and mice.

As for human studies:

Increased fruit and vegetable consumption has been associated with the decreased risk of a number of cancers of epithelial origin, including esophageal cancer.

As an aside, I prefer the British spelling for oesophagus, the oe looks more dignified and I do say “oh-sophagus” or “oo-sophagus”

It is hard to know how much bioactives we are consuming. This is partly, as this article reports, because the amount of phytochemicals present in foods is not known and changes dramatically depending on growing conditions. Organic strawberries had a greater effect on human colon and breast tumor cells than conventionally grown strawberries. Organic berries were more effective probably because they contain more secondary metabolites than conventionally grown fruit.In addition:

Studies have shown a high variability in phenolic intake based on variations in individual food preferences. A high daily intake of fruits and vegetables is estimated to provide up to 1 g of phenolics.

Unfortunately, “high daily intake of fruits and vegetables” is not defined in the article.

Even if we know how much of the bioactive compounds we consume, we still do not know how bio-available these phenolics in berries or other fruit.

I find it amusing that articles always end up with a statement which in effect says “more research is needed, I am the best person to do it and I need funding now“. In this article the concluding paragraph goes:

In conclusion, it is strongly recommended that this area of research for berry fruits continue to be explored, as this will lay the foundation for the development of diet-based strategies for the prevention and therapy of self types of human cancers.

My conclusion?

Eat lots of berries, now and forever more. Fortunately, I have lots in my freezer. Yum.

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Reference:

(1) Seeram, N.P. (2008). Berry Fruits for Cancer Prevention: Current Status and Future Prospects. Journal of Agricultural and Food Chemistry DOI: 10.1021/jf072504n
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