• New Sous Vide Perspectives

    Posted by PolyScience Staff

    Although I’ve been cooking Sous Vide for over 10 years, I jumped at the chance to attend a CREA-sponsored class led by Bruno Goussault, the Chief Scientist at Cuisine Solutions, Inc. After all, how often do you get a chance to learn directly from the man often referred to as the “Father of Sous Vide Cooking”?

    In my case, the CREA (Culinary Research & Education Academy www.lecrea.com ) hosted by Kendall College in November ranks right up there with Bruno’s workshop I attended about 8 years ago alongside Wylie Dufresne and his team from wd~50 and Jean-Georges Vongerichten’s staff from his eponymous award-winning restaurant, Jean-Georges. I hope you get the idea that this was a big deal.

    Bruno provided a wide array of thought provoking ideas. I’d like to share a couple of those takeaways in hopes that they will help and inspire you to further explore Sous Vide cooking and its many benefits.

    To get started, it’s important to know that Bruno isn’t the kind of guy that let’s you take anything for granted. Instead, he challenges each student to think through all of the culinary ideas they’ve been carrying around and forces you to firm up those that haven’t fully gelled. No detail or idea is apparently too small or fundamental in his quest for culinary perfection.

    For example, Bruno’s notion that we cook to “modify the functional properties of food” may seem incredibly obvious, but how many of us have actually thought it through? As we moved through the three-day program, that definition provided direction when evaluating how best to prepare a wide variety of ingredients that are seldom uniform.

    We learned, for example, that game can be relatively hard to cook compared to domestic animals because of its elevated lactic acid levels created by physical activity. Consequently, Bruno suggests that we always separate the rabbits we want to eat from ones of the opposite sex at least one week prior to slaughter to eliminate the physical activity they are known to engage in. The more sedate rabbits will taste better than those that were active.

    Similarly, not all beef is the same. The cooking times of American versus European beef is a good case-in-point. More specifically, European beef often requires longer cooking times because it is usually slaughtered older and because the US animals have been subjected to practices that increase growth rates and fat content.

     

    Focusing on fish, Bruno suggests that the product should always be salted before cooking to block the unattractive release of albumin through osmotic pressure.

    When Bruno prepares vegetables, he always uses an extended vacuum hold to draw air from inside their dense structures. He then adds some fat to absorb aromatics and flavor and cooks at 83C, safely below the 85C where he claims pectin becomes active. In the class we cooked all vegetables for 3 hours. He chills vegetables then re-heats them, even if serving soon after cooking, to retain the aromatic qualities.

    Regardless of whether he’s cooking meat, fish or vegetables, Bruno chills the products by first subjecting them to ambient temperatures for 5 minutes, then to an ambient bath for 5 minutes, and finally to an ice bath. For meat and fish he theorizes the process allows re-absorption of fats and gelatin that would not occur if you go directly to an ice bath. In the case of vegetables, he believes that when you open a hot vacuum sealed bag you allow the “perfume” of the product to escape. By cooling the product and reheating to a moderate serving temperature such as 56C, you alternatively retain the aromatics.

    Bruno notes that adding ascorbic acid as an antioxidant can help vegetables, especially artichokes, retain their color. Adding lemon will release ascorbic acid, but he warns against squeezing to avoid releasing citric acid. He suggests adding fructose or balsamic to fix the color of beets and other vegetables.

    In all of our cooking we used probes to determine actual core temperatures. I personally have a love/hate relationship with probing, but it is the best method to truly understand core temperature. I was pleased that when I compared our PolyScience Sous Vide Toolbox iPhone/iPad application, our predicted temperatures agreed with the probes. Unfortunately you can’t tell that to a health department inspector.

    Bruno typically prefers what he calls “Step” Sous Vide Cooking. This is different from the way I have utilized the Sous Vide technique in which I generally have my bath within 1 degree of the desired core temperature. Instead, Bruno will start the cooking process in an 83C bath for a short period (typically 3-5 minutes) and then move the food to a bath set closer to desired core temperature.

    I see some advantages to this “Step” approach. First, you kill surface bacteria. Additionally you create some textural variations that can make some foods such as cod or sea bass more varied and interesting.

    The list goes on and will be the basis of future postings.

    If you have the opportunity to attend one of Bruno’s classes you will leave with a much better understanding of how to cook Sous Vide with great results and safety.

    Philip Preston
    President
    PolyScience

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  • Time and Temperature Reference

    Posted by PolyScience Staff

     

    This table is only meant to serve as a guideline. Temperatures should be adjusted to your preference of doneness. Cooking time should be adjusted to initial temperature, heat transfer characteristics, and thickness of the food being cooked. Times denoted with an * include time for tenderness.

    Temperature Thickness Time to Core Temperature Time (Pasteurized to Core)
    BEEF
    Tenderloin 138°F / 59°C 2 inches 1 hour, 58 min 5 hours, 35 min
    Rib Eye Steak 138°F / 59°C 1.5 inches 1 hour, 58 min 3 hours, 20 min
    Strip Steak 138°F / 59°C 1.5 inches 1 hour, 58 min 3 hours, 20 min
    Porterhouse Steak 138°F / 59°C 1.5 inches 1 hour, 58 min 3 hours, 20 min
    Brisket 147°F / 64°C 48 Hours* 3 hours, 21 min
    Veal Shank 167°F / 75°C 12-24 Hours* 9 hours, 03 min
    LAMB
    Lamb Saddle 138°F / 59°C 2.5 inches 2 hours, 16 min 3 hours, 51 min
    PORK
    Pork Chop 145°F / 63°C 1.75 inches 1 hour, 45 min 4 hours, 02 min
    Ribs 140°F / 60°C 24-48 hours* 1 hour, 06 min
    POULTRY
    Chicken Breast 150°F / 65°C 1 inch 47 min 1 hour, 36 min
    Duck Breast 135°F / 57°C 1 inch 60 min 2 hours, 41 min
    Chicken Thighs 150°F / 65°C 1.5 inches 1 hours, 20 min 3 hours, 03 min
    Foie Gras 147°F / 64°C 2 inches 2 hours, 16 min 5 hours, 09 min
    FISH
    Salmon Filet 130°F / 54.4°C 1 inch 1 hour, 39 min 5 hours, 31 min
    Cod Filet 129°F / 54°C 1 inch 1 hour, 39 min 3 hours, 47 min
    Halibut 129°F / 54°C 1 inch 1 hour, 39 min 3 hours, 47 min
    SHELLFISH
    Shrimp / Prawns 135°F / 57°C 1 inch 43 min 5 hours, 21 min
    Lobster 145°F / 63°C 1 inch 15 min 5 hours, 5 min
    Scallops 135°F / 57°C 1.5 inches 1 hour, 38 min 2 hours, 29 min
    VEGETABLES
    Root – Whole (Beets, Carrots, Potatoes, etc.) 190°F / 88°C 60 min
    Root – Cut (Beets, Carrots, Potatoes, etc.) 185°F / 85°C 30-40 min
    Bulb – Whole (Onions, Shallots etc.) 194°F / 90°C 85 min
    Squash – Cut 185°F / 85°C 30 min
    Artichoke Hearts 194°F / 90°C 60-75 min
    FRUIT
    Peach Wedges 190°F / 88°C 16 min
    Pear Wedges 190°F / 88°C 60 min
    Apple Slices 190°F / 88°C 40 min
    EGGS IN SHELL
    Soft Poached Egg 143°F / 62°C 57 min 44 min
    CUSTARD
    Crème Anglaise 179.6°F / 82°C 20 min

     

    Note: Times shown in this reference are to achieve the absolute specified core temperature. Cook times can be reduced significantly by adding (1) degree to the water bath temperature. When there is little difference between bath temperature and core temperature, change occurs very slowly.

    To rapidly kill surface bacteria, immerse product in boiling water for approximately 60 seconds.

    Raw or unpasteurized food must never be served to individuals with a weakened immune system, children, older adults and those that may be pregnant as there is higher risk for serious illness.

    For more specifications on time and temperature, download the PolyScience Sous Vide Toolbox application for iPad and iPhone.

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  • Food Safety with Sous Vide Cooking

    Posted by PolyScience Staff

     

    Table of Contents:

     
     

    A: Sous Vide Cooking Process

    As with any food process, sous vide requires specified food handling practices to prevent, eliminate, or reduce the food biological, chemical, and physical hazards to a safe level.

    Three important aspects require additional attention:

    • When food is vacuum packed Vacuum-packaged food creates an anaerobic (oxygen-free) or reduced oxygen environment. With improper food handling, some of the most dangerous bacteria can grow, such as salmonella and botulism. Safe food handling and hygiene standards should always be maintained.
    • Food cooked at low temperatures for extended periods of time can cause bacteria to multiply rapidly. The longer food is in the “danger zone” — temperatures between 40°F and 140°F (4.4°C to 60°C) — the faster bacteria can multiply and the more dangerous they can become.
    • When food in pouch has finished the required cooking time, it has to be removed and served immediately, or rapidly chilled. Cooling must be less than 6 hours from 130 to 41ºF.

    Carefully read and incorporate these detailed guidelines into your cooking method to assure safety in each step.  
    Prerequisites to food preparation.

    • Make sure that the refrigerator is 41ºF or colder.  The colder the refrigerator, the slower the spoilage of ingredients.
    • Get an accurate digital food thermometer to check the temperature of the raw and cooked food to assure that it reached a desired end point.
    • Get the plastic pouches that the food will be packaged in.  Make sure that they are not contaminated.
    • Use detergent,  warm water, wash ,  and rinse the food contact surfaces.  Sanitize the surfaces with a solution of 1 teaspoon chlorine bleach per gallon of water to prevent cross-contamination.
    • Be sure to separate the raw ingredient preparation area from the finished product area, or wash, rinse, and sanitize a surface when changing from raw preparation to finished food.

    Sous vide processing. 

    • The basic steps of the sous vide process are shown in the following flow chart. Details to each step are provided below the flow chart.
    Prepare the work area.  Put away unnecessary objects.  Clean and sanitize food contact surfaces, and store chemicals so that they cannot contaminate the food.

    Get fresh ingredients.  Sous vide cannot make spoiled ingredients taste good. It amplifies the flavors and should only be applied to the freshest ingredients.

    Trim, cut, and prepare ingredients.  Remember, the thicker the protein ingredient, the longer it takes to come to its cooking temperature. Less than 2 inch thickness is a practical maximum thickness.  Weigh additives carefully. Safe cook times can be calculated in PolyScience iPhone/iPad app “Sous Vide Toolbox”

    Package / vacuum seal.  The purpose of the vacuum is to pull the plastic pouch film tight to the food for good heat transfer.  Check the seal.

    Cook / pasteurize.  Reduce vegetative pathogens such as Salmonella 5 log (100,000 to 1).  Cooking / pasteurization begins about 130ºF.

    Hold at cooking temperature until desired degree of doneness is achieved.

    Cool fast enough to prevent the outgrowth of spores.

    Cold hold meat, poultry, and vegetables at 41ºF to prevent the outgrowth of spores and slow growth of spoilage organisms.

    Warm (reheating) and serve.

     

    Set Up Sous Vide Professional and Water Bath

    • Clamp Sous Vide Professional to a stockpot or any other vessel. Fill with water up to maximum level, indicated on Sous Vide Professional.
    • To guarantee precise temperature control, refer to user manual for maximum water volume. For example the Sous Vide Professional CHEF Series has a maximum of seven gallons or twenty eight liters of water. A second Sous Vide Professional may be required to maintain the level of precise temperature control with larger volumes.
    • Set the Sous Vide Professional to desired temperature. Cover bath with lid or plastic wrap for efficient heat-up time and to avoid evaporation.

     

    Get fresh ingredients; Trim, cut, and prepare ingredients. 

    • One must start with very fresh ingredients in order to assure that off-flavors from spoilage are minimal and are not amplified in the cooking method.  Also, by focusing on freshness, it will assure lower spoilage bacteria counts at the start of refrigerated storage so that the finished product will have a longer refrigerated shelf life.
    • It is safer if you use solid, not ground or punctured, pieces of meat, poultry, or fish.  When it is punctured, it becomes critical that, not just the surface, but the center of the food get hot enough for long enough to be pasteurized.
    • Since cooking is done in a plastic pouch, there is no loss of flavor volatiles in sous vide cooking.

    Package / vacuum seal. 

    • The vacuum is not for flavor.  It is to have a good heat transfer between the water bath and the surface of the food.
    • Assure that food-grade quality plastic pouches that have not become contaminated in storage are used; 2-3 ml plastic is adequate. If zip-loc type bags are used, assure that they are heat-safe to the temperatures you will be cooking at.
    • Make sure food is refrigerated at 38°F (3.3°C) or below until ready to seal.
    • To ensure precise and even cooking, arrange pieces of food in the plastic bag in a single layer.
    • Check vacuum bag for proper seal before cooking.
    • As bags are sealed, check to be sure that there was no crease in the plastic and that the seal is uniform with an even fusing from one side to the other.
    • After sealing, immediately cook or refrigerate food at 38°F (3.3°C) or below until ready to cook (see storing tips on the following page).

    Cook / pasteurize. 

    • Insert vacuum-sealed bag only when bath has reached correct temperature.
    • Follow time and temperatures guidelines and consider increasing cooking time if food has a larger diameter than specified in the recipe.
    • Cooking time increases by a factor of almost 4 times per extra inch. If you only double the time per inch, it will be unsafe!
    • In case you are not able to remove all the air due to limitations of your vacuum sealer, you can weigh down the pouch with a heavy porcelain plate to ensure it is fully submerged. This is important to ensure safe cooking results.
    • If you cook more than one vacuum bag, make sure they are not too close to each other.
    • Make sure to hold the pouch under the water so that it is fully cooked.  Food safety times and temperatures are based on center temperatures of the food.
    • Check temperature and sealed vacuum bag frequently during cooking process. A bag that suddenly begins to float, inflate, or leak is a sign of food-safety issues. Discard food and clean tank and Sous Vide Professional.
    • If during cooking in the water bath, the bag balloons and floats to the surface, a seal has failed, or the temperature is too hot and steam has formed in the package, or there is a pinhole.  The package must be thrown away, because you do not know if there was adequate heat transfer and pasteurization was effective.
    • Always measure the internal temperature of foods before serving. You can re-seal a pouch and continue cooking if necessary.
    • If you are making more than one pouch, a very smart thing to do is to sample the first pouch removed from cooking.  Take your digital thermometer and verify the center temperature of the food.  Also sample the flavor of the product.  If it needs more cooking, you can reseal the pouch and continue to cook.
    • If you are cooking fish to a temperature of less than 130ºF, there are parasite and vegetative pathogen risks.  Undercooked fish should have been frozen at -4ºF for 7 days to assure the destruction of the parasite, and the customer should be informed that undercooked food has some illness risk.

    There will be two primary biological hazards in the meat, poultry, fish, vegetables or fruit that are cooked sous vide.

    The first hazard is vegetative pathogens, and the regulatory target is Salmonella.  The goal is to cook the food in the pouch to a time and temperature to reduce Salmonella 100,000-to-1.  This will reduce the Salmonella from a maximum of 1,000 per gram in the raw food to 1 per 100 grams in the finished food.  Salmonella is used as the target organism, because it has been, and continues to be, a major cause of illness and kills an estimated 500 people each year.

    The government-specified times and temperatures for this pasteurization are:

    Center temperature

    Hold time

    130ºF

    112 minutes

    140ºF

    11 minutes

    150ºF

    1 minute

    155ºF

    5 seconds

    158ºF

    instant (less than 1 second)

    The second biological hazard common to the ingredients from the water and land farms are the spores, Clostridium botulinum [proteolytic (meat, poultry) and non-proteolytic (fish, seafood)], Bacillus cereus (cereal products), and Clostridium perfringens (meat, poultry, lentils).

    When the food is pasteurized, Salmonella is reduced to an Appropriate Level of Protection (ALOP), but pasteurization temperatures have no kill effect on the spores.  Pasteurization just activates the spore.

    IMPORTANT:
    It’s a rule-of-thumb that if you cook below 130°F (54.4°C) there is an increased risk for vegetative pathogen and parasite development. However, food safety depends on a combination of temperature, time, pH level and the freshness of the ingredients. Extended cooking time pasteurizes food and reduces potential Salmonella to an appropriate level.

    Hold. 

    • After the food is pasteurized, if the food is hotter than 130ºF, the spores cannot germinate and multiply, regardless of time.
    • One can hold / tenderize for 24 to 48 hours safely.  This is also a major feature of sous vide.
    • If the cooking temperature is 130 to 150ºF, there is an additional benefit.  The enzymes are very active, and the meat becomes very tender.

    Chill.

    • At this point, the spore is activated (pasteurization has no kill effect on spores, it activates spores); so, cooling becomes a critical control procedure.
    • The target spore for cooling is Clostridium perfringens.  It must be controlled so that there is less than 1 to 10 increase in population during cooling.
    • To assure safety, cooling must be less than 6 hours from 130 to 41ºF.  This is easily done for most sous vide products if they are less than 2 inches thick in an proper ice bath.
    • The recommendation for a proper ice bath is: ratio of 1lb ice to 1lb product, topped off with cold tap water. Agitation will increase the effect of a rapid chill process.
    • It limits roasts to about 5 pounds.  After the cooling to 41ºF, C. perfringens cannot multiply, and the target spore for storage is Bacillus cereus for all food except fish.  Holding at 41ºF controls B. cereus.
    • For cooked fish, there is a critical limit of 37.4ºF to prevent the non-proteolytic C. botulinum on the fish from growing.  If cooked fish is to be stored after cooling, it should be frozen or held in ice at less than 37.4ºF, or served within 7 days if held at 41ºF.

    Cold hold.

    • Before storing, label vacuum-sealed bags with expiration date and contents.
    • For practical purposes, if the preceding instructions are followed there is probably no significant reason to hold sous vide product for more than 7 days.
    • If the recipe includes inhibitors, such as salt or acidity, food can be stored up to 45 days, as long as temperature is meat and poultry is 41ºF or colder, or fish and seafood is less than 37.4F (3.0ºC).
    • Only spores or some surviving spoilage organisms can multiply, and temperature is the critical control.

    Warm (reheating) and serve. 

    • Reheating is not for safety; it is a quality factor to meet consumer desires.
    • The food is safe if the preceding instructions are followed, and the food can be eaten cold from the pouch or removed from the pouch and browned and heated to suit the consumer.
    • When reheating cooked food, simply bring water bath back to desired serving temperature and apply time needed for core to reach temperature.
    • Always measure the internal temperature of foods before serving. You can re-seal a pouch and continue cooking if necessary.
    • If reheated in the bag, consider that spores or some surviving spoilage organisms can multiply. Temperature is the critical control.
    • A major safety advantage of sous vide is that it was pasteurized in the package, so there is no chance of contamination of the product by vegetative pathogens in storage after cooling.
    • Frozen, cooked foods must thaw under refrigeration (41°F or below) and reheated upon complete thaw, prior to consumption.

    Top

     

     

    B: Highly Susceptible Audience

    Children, elderly and expectant mothers and those with compromised immune systems should not consume raw or undercooked foods.

    Many temperatures listed on this website (www.polyscienceculinary.com) and within PolyScience Sous Vide Professional™ literature, manuals, applications and marketing include “threshold temperatures,” which are considered to be at the low end of FDA required cooking temperatures.

    Anyone in these audiences should cook all recipes listed on this website or within PolyScience Sous Vide Professional™ literature, manuals, applications and marketing 2°C/4°F higher than listed in the recipe and for 5% more time (Calculator) to ensure proper cooking temperatures and pathogenic reduction. For further information of accepted safe cooking temperatures, please visit www.FDA.gov

     

     

    C: Further Resources

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  • Bacon Ice Cream Lollipops w/ Cacao Nibs

    Posted by PolyScience Staff

     

     

    Bacon Ice Cream Lollipops w/ Cacao Nibs

    Ingredients:

    6 Egg Yolks

    3oz Sugar

    ½ Vanilla Bean

    7oz Milk

    9oz Heavy Cream

    9oz Bacon, Chopped, Rendered (Reserve fat and bacon separately)

    Cacao Nibs (as needed)

     

    Method:

    Step 1: Preheat a waterbath to 185 degrees Fahrenheit

    Step 2: Cream the egg yolks, sugar, and bacon fat in a stand mixer.

    Step 3: Add the vanilla bean and whisk in the cream and milk. 

    Step 4: Pour the liquid into a vacuum pouch and vacuum seal it.

    Step 5: Cook the mixture for 20 minutes. After 20 minutes has elapsed, remove the pouch from the waterbath and let it sit at room temperature for 5 minutes before transferring it to an ice bath. 

    Step 6: Refrigerate the mixture for 1 day before pouring it into an ISI canister. 

    Step 7: Charge twice with No2, shaking the canister vigorously after each charge.

    Step 8: Freeze for 5 minutes on the Anti-Griddle. Insert a lollipop stick and garnish with reserved bacon and cacao nibs half way through freezing.

     

    Recipe courtesy of Chef Libry Darusman

    www.hospitalitycollaborative.com

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  • Sous Vide Turkey Stuffing

    Posted by PolyScience Staff

    Super simple Thanksgiving stuffing.

    Serves: 8

    Prep time: 10 minutes
    Cook time: 60 minutes

    Ingredients:
    2 Baguettes, day old, medium dice

    1 White Onion, medium dice
    2 Stalks of Celery, medium dice
    3 Sprigs of Thyme, picked and chopped
    1t Marmite
    16oz Turkey Stock (May substitute: chicken stock)

    8-10 Roasted and Peeled Chestnuts, small dice
    Kosher Salt and Black Pepper, to Taste

     

    Step 1:
    Set the Sous Vide Professional™ to 167°F/75°C, with the Rear Flow Adjustment Slide closed and Front Flow Adjustment Slide fully open. (Flow Adjustment Slide available on CHEF Series only.)

    Step 2:
    Combine onion, celery, thyme, Marmite and stock. Do not add bread, chestnuts and seasoning at this point. Stir gently to combine ingredients.

    Step 3:
    Roll the vacuum pouch back at the top, turning it out 1-2 inches. This will help prevent possible cross-contamination.

    Step 4:
    Pour mixed vegetables into vacuum pouch, vacuum seal.

    Step 5:
    Place sealed bag in circulating water bath and cook for 40 minutes.

    Step 6:
    Remove bag from water bath.

    Step 7:
    In a large mixing bowl, combine diced bread and chestnuts. Open and pour sous vide vegetables and stock from earlier. Stir gently to combine all ingredients.

    Step 8:
    Place stuffing mix in a new, larger vacuum bag. Be sure to roll the vacuum pouch back at the top, turning it out 1-2 inches. This will help prevent possible cross-contamination. Place stuffing bag, unsealed, in a refrigerator for 10 minutes.

    Step 9:
    Remove cooled bag from refrigerator and vacuum seal.

    Step 10:
    Place sealed bag in circulating water bath and cook for 10 minutes. Remove and fluff with a fork. Stuffing can be toasted in an oven or cooled completely and placed inside the cavity of the turkey.

    If serving immediately: transfer to serving vessel.

    If saving for later: quickly shock in ice water bath until temperature has reached 40°F/4°C. Cooling must occur in under one hour. Store in refrigerator and reheat to 140°F/60°C before serving.

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