Storing Cucumbers

Storing Cucumbers

When storing cucumbers, you need to consider whether you just need short term storage or if you want to preserve your cucumbers for the long term.

Short Term Storage (Fresh Cucumbers):

Cucumbers from the supermarket are often waxed to seal in moisture. Cucumbers that have not been waxed can be tightly wrapped in plastic wrap for the same reason.

To store cucumbers, first wipe them clean with a damp cloth.

Cucumbers should be stored in a cool (but not cold) environment. The ideal storage environment would have a temperature of 50°F to 55°F (10°C to 13°C) and a relative humidity of 95%. If cucumbers are stored for long periods at temperatures below 40°F (5°C), they will develop pitting and get soft and mushy. That said, it is still okay to store cucumbers in the vegetable crisper of your refrigerator for a few days.

Cucumbers can be stored for about 2 weeks.

Long Term Storage (Pickling):

Don’t freeze cucumbers. The best long term storage solution for cucumbers is to pickle them. There are particular varieties of cucumber that are best suited to pickling, however, any variety can be pickled. Cucumbers can be pickled by fermenting or with a vinegar solution, then processed in a boiling water bath.

Pickled cucumbers can keep for up to a year.

Cucumbers and Ethylene:

Cucumbers Produce very low amounts of ethylene, but they are very ethylene sensitive. Because of this, cucumbers should never be stored with high ethylene producers like apples, pears, or tomatoes.

If you found this post useful, or if you have any tips for storing cucumbers, please leave a comment.

Posted in Food Storage

Alkannin, A Red Food Dye

Alkanet / Alkannin


Alkanet or alkannin is a food dye.  It gives a red colour to foods, clothing, and cosmetics.


Alkannin is the name of the food colouring made from the Alkanent plant.  In fact, several related plants in the borage family share the common name Alkanet.  Alkanna tinctoria (also called Dyer’s Bugloss) is the most common variety.  Alkannin is the name of the food colouring made from Alkanent.  It is soluble in oil and alcohol, but not water.

Alkanet has blue flowers and a dark red root that appears to be almost black on the outside. Inside, the root has blue-red colour, with a whitish core. The root produces the red dye.

Alkanet grows in the Mediterrean (including the south of France and parts of Lebannon).

Alkannin is made from the plant alkanna tinctoria
CC BY-SA 3.0, Alkannin is made from the plant alkanna tinctoria


Common Uses:

Alkanet is traditionally used in Indian food under the name “Ratan Jot”, and lends its red colour to some versions of the curry dish Rogan Josh. In Australia alkanet is approved for use as a food colouring, but in the European Union it is not.


Other Uses:

It dyes cloth and colours food. Cosmetics may also get colour from alkannin.

Alkannin can also be used as an acid indicator. It is red at pH 6.8, changing to purple at pH 8.8 and finally, blue at pH 10.

The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic.

In the past, It has been used to color wine to make it look more appealing, or to color the corks so it looks more aged.

Side Effects / Health Issues:

So far, I have not found any references that indicate potential health issues or side effects resulting from the consumption of foods colored with alkannin.

There is some evidence that alkanna tinctoria can have wound healing and anti-inflammatory effects.1

E Number:

The E Number of alkanet or alkannin is E103.  However, it is no longer approved for use in Europe.  It is also not listed in the FDA’s list of food colours approved in the the USA.  It is still allowed in other countries such as Canada.


  1. The Chemistry and Biology of Alkannin, Shikonin, and Related
    Naphthazarin Natural Products
  2. Sharmilazkitchen – Ratan Jot
  3. Health Canada List of Permitted Food Colouring Agents
  4. FDA Color Additives Listed for Use in Food
Posted in Colour, Food Additives, Ingredients

Allura Red

picture of an azo compound

Allura Red


Allura red (also known as red dye 40) is an artificial dye used to colour foods, medications, and cosmetics.


Byproducts of the petroleum industry are used to produce allura red.  In fact, many organic compounds used in food additives and pharmaceuticals come from petroleum products.

It looks like a dark red powder.

When you look it up, you often see allura red described as an azo dye.  So, what does that even mean?

Very simply put, an azo dye is a chemical compound where two hydrocarbon groups (A hydrocarbon is an organic compound made entirely from hydrogen and carbon atoms.  There are many different kinds of hydrocarbons) are joined by two nitrogen atoms.  The letters azo are derived from the french word for nitrogen, azote.

Azo dyes account for roughly 60 to 70% of all dyes used in the food and textile industries.  The reason they are so popular is that azo dyes are cheap to produce and are more stable than most natural food dyes.

allura red is an azo dye. this picture shows an azo molecule

azo compound

Allura Red is banned in many European countries including Denmark, Belgium, France and Switzerland.  It is approved by the European Union and has been assigned an E number.  However, the local laws in EU countries take precedence.  It is also approved in the United States and Canada.  In the US, the Center for Science in the Public Interest has been calling for the FDA to ban Allura Red.

Common Uses:

Allura red is commonly used in many processed foods including baked goods, candy, cereal, dairy products, drinks, sauces, and snacks.1

Side Effects / Health Issues:

On it’s own, allura red is not particularly toxic.  You would have to eat many kilograms of a food coloured with allura red in a single day to receive a lethal dose.2

People who have a salicylate intolerance (aspirin is the most common salicylate drug) may have similar reactions to allura red.

Additionally, it is a histamine liberator, and may intensify symptoms of asthma. One of its degradation products causes bladder cancer in animals when present in high concentrations.

Recent studies have also found links between hyperactivity in children and the consumption of artificial food dyes and preservatives.3

E Number:

The E number of allura red is E 129.

Other red food colourings include:

Other Web Sites:

  1. UK Food Guide


  1. Red Dye Food List
  2. Food-Info
  3. The Lancet – Food additives and Hyperactive Behaviour



Posted in Food Additives

Storing Brussels Sprouts

Storing Brussels Sprouts:

The following tips will help you with storing Brussels Sprouts:

  1. Any wilted or yellow leaves should be gently removed before storing Brussels sprouts.
  2. Don’t wash the Brussels sprouts before storing them.
  3. Loosely wrap your Brussels sprouts in a paper towel and then wrap in a plastic bag.  Store the plastic bag in the vegetable crisper of your refrigerator.

Brussels sprouts can be stored in the refrigerator for about 2 weeks.

If you can accurately control your storage conditions, storing Brussels sprouts at 32°F (0°C) with a relative humidity of 95 to 100%, will allow you to keep them for up to 5 weeks.  However, it should be noted that the longer Brussels sprouts are stored, the stronger their flavour becomes.  Many people may find the stronger flavour undesirable.

For long term storage, the best option is to blanch and freeze your Brussels sprouts.

Storing at room temperature will quickly turn the leaves yellow.

Ethylene Gas Production and Sensitivity:

Some ripening fruits and vegetables will give off a gas called ethylene.  This gas will cause vegetables and other fruit to deteriorate at a higher rate.  Ethylene gas is produced by some fruits and vegetables at a much higher rate than from others.  Brussels sprouts produce more ethylene gas than most other leafy green vegetables, but they are still considered to be low producers of ethylene.

On the other hand, Brussels sprouts themselves are quite sensitive to ethylene.  When exposed, the leaves will turn yellow and fall off at a faster rate.  Therefore, Brussels sprouts should not be stored together with high ethylene producing fruits and vegetables (like apples).


If you found this post useful, or if you have any tips for storing Brussels sprouts, please leave a comment.

Posted in Food Storage, Fresh Food

Storing Leeks

Storing Leeks

Leeks are part of the same family as onions and garlic.  They do give off odors that can be absorbed by other foods.

However, unlike onions and garlic, leeks can (and should) be stored in the refrigerator.  Before storing leeks, trim any bruised or damaged leaves and roots.  Do not wash leeks before storing them in a perforated plastic bag in your refrigerator’s vegetable crisper.  Storing leeks in plastic helps them hold onto moisture and keep the odor from spreading to other foods.

Ideal conditions for storing leeks are:

  • Temerature: 32°F (0°C)
  • Relative Humidity: 90-95%

Leeks produce very little ethylene and are only moderately sensitive to ethylene produced by other fruits and vegetables.  When leeks are exposed to ethylene gas they tend to soften are decay a bit faster.

Leeks can be stored for about 1 week.

Leeks can be frozen.  Leeks do not need to be blanched before freezing however, they should be washed and sliced.  To maintain the best possible flavour, the leeks should be cooked as soon as they are removed from the freezer.  Don’t allow them to thaw.

Leeks can be frozen for about 5 months.

If you found this post useful, or if you have any tips for storing leeks, please leave a comment.

Posted in Food Storage, Fresh Food

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