I had a dream, lecturing a group of wanna be chefs bored when I told them, you can get sick from touching backyard poultry and swallowing Salmonella germs. Salmonella is a real problem but chicken is not the only culprit, nuts, fruits, vegetables and wherever it can grow.
According to the CDC, Center for Disease Control and Prevention, claim approximately 48 million Americans get sick, 128,000 are hospitalised and 3,000 die each year from food poisoning: https://www.cdc.gov Think of it this way, food is an excellent medium for bacteria and that’s not to mention bacteria humans carry or transfer onto foods. So, when we cook or vacuum our foods we should try and be sure our foods are free from any contamination, so vacuum foods cold is a good starting point, unless you smoke the foods.
Ask yourself, when do you know if food is safe to eat when it comes to low temperature cooking? The reference bible I use when it comes to most kitchen queries is Modernist Cuisine, a fantastic reference for any kitchen, and any kitchen without Modernist Cuisine is like a car without fuel, it cannot run.
Many home chefs using sous vide tools often are surprised at the temperatures being used. When it comes to food safety we all need to pay careful attention to what happens not only when we cook, but when we work, or store foods. Experimenting with friends I cooked chicken breast using sous vide, it was a shock when I showed the breast was cooked at 63°C, pinkish. The first reaction was not to eat it, and it makes sense when most chicken breast’s are cooked in the oven at 180°C until solid white. It is mostly what we are used to, standardised home cooking techniques and tradition is what we are used to.
Recently, I was cooking veal and chicken using sous vide, and found the meat even if it was in the range of safe cooking, it seemed out of the norm. The physical inspection, the look and texture of any cooked meat is always the starting point when it comes to perceiving whether it is cooked or undercooked. You can cook veal at 57°C and discover the meat is safe to eat, yet for most this temperature is simply too low due to the look and texture.
The same applies for chicken and you can cook chicken at 63°C and it is pinkish, but for 99% of the population they easily feel uncomfortable with the pinkish look, a physical eye examination tells us something is wrong. But these aspects are mostly based on our learned comfort zones, the place we learn (home) about what is safe and what is dangerous.
Now, the most important aspect when cooking any meat is how you manage the pre-process., i.e. what we do before vacuuming the food. I start with cold foods, foods stored in a fridge and certainly at 3/4°C the food is cold enough. Always keep in mind micro-organisms, due to spoilage and pathogenic grow rapidly at room temperature and the more time, the more growth. And now comes the cooking process and the optimization.
My secret to sous vide cooking is minimising liquids, and or risk flavours you may not have control *that’s my basic rule. For example today I am cooking beef ribs 36 hours without adding flavours, or olive oil. Sometimes flavours are necessary to add when cooking low temperature, the big word is umami: https://mesubim.com/2013/02/12/umami-me/
Most of what we do in kitchens are habits, even myths, or misconceptions but flavours give us the ultimate pleasure in food. When someone tells you add olive oil to a sous vide steak it makes me wonder. True denatured meats can absorb oils, olive or others, so using extra virgin olive oil helps pull fat-soluble flavours out of marinade ingredients like shallots and garlic but does it penetrate and add flavours to the meats cooked in sous vide.
I am never sure when preparing meats in sous vide if I should add flavour enhancers and unless you are sure, avoid it at all costs or risk failure. I know some will argue if you do it right, it is suitable and that is true. For example, some flavours can easily work while others change and become bitter, or loose aromatics if they are cooked for long periods. I am not saying you shouldn’t add oil, garlic or other flavour enhancers, but be careful and know what works by using indicators from reliable sources or from personal experience.
Coming back to liquids, I dislike when I cook sous vide and discover at the end of cooking my meat within the vacuumed bag is filled with an over abundance of juices. It is rather disgusting to see how much moisture, excess blood, or H2O is left behind. Low heat draws liquids out of the meat and if the meat is fresh and packed in blood, as many meats are, you will suffer those nasty liquids. But Myoglobin in meat is what gives it its red colour, and denaturation is responsible for the colour change between raw and cooked meat. This change occurs at 60°C when protein molecules denature, their coiled structure unfolds. So, when you cook at 55°C as I do I preserve the colour.
In fact, the idea of sous vide meats maintained in their own blood is normal and meat producers and suppliers realised blood preserves meat and prolongs its shelf life. In fact, freshly slaughtered cow’s meat is purplish due to exposure to oxygen during the packing process and turns cherry-red, a colour we’ve come to associate with freshness of meat.
The best way is to avoid the meats juices is none other than dry ageing and I always dry age whatever I cook in sous vide, otherwise I get what I call bloody-hell, the heat pushes out the blood and H20 with the end result a flimsy, floppy raw looking piece of soggy meat. Dry ageing is an absolute must if you wish to have a proper steak.
Even though salts, and sugar to a much lesser extent, are the only flavorings that can penetrate the complex matrix of proteins we call muscle, yet many people insist on putting other things in the sous vide bags such as olive oil. Because the temperatures used in sous vide are so low, the proteins in the juices rarely coagulate: https://meat.tamu.edu/people/
Some chefs try to salvage the juices by adding water and whatever herbs/spices to flavour. By using egg whites to facilitate the clarification process you can clarify or clear the fluids. When the fluid is heated, added egg white water, lemon and even the egg’s shell, it helps coagulate, capturing and holding minute particles and then strain.
Recipe for 1 litre of stock:
2 tables spoons water
1/2 table spoon lemon
Chop the egg shells and mix
Add to the stock luck warm and simmer 5 minutes
Once egg white coagulate and get darker you use a chinois and filter
Consider along with water, protein is a key component of eggs and proteins are made of long chains of amino acids tightly coiled by weak bonds. When protein is heated or air is beaten into it, its bonds come apart, and the chain partly unwind. As the proteins unfold, they expose their hydrophobic (water-hating) and hydrophilic (water-loving) ends. The proteins form new bonds, arranging themselves so their water-hating ends are in the air and the water-loving ends are in the water. This creates a web of protein molecules that hold the air bubbles in place. If the proteins are overheated or overbeaten, the bonds will tighten and squeeze out the moisture, leaving the eggs dry, firm and rubbery.
The complexities of flavours isn’t just taste but the physical appearance which often dictates what we think. Cooking is much more visual than anything else, I’ll never forget when I first started eating sushi, my mom told me, ‘be careful” and raw was almost non-existent. I was certainly afraid, it was 1970’s and no one would dare and eat sushi, it was raw !!!
I was hooked on the bite sized finger foods, umami enhanced, it is those very flavours you get addicted to easily. Over time I discovered Japanese cuisine and moved to Tokyo in the early 1980’s to explore a cuisine I adored.