Introduction

Ever wondered what the difference between plums and prunes is? We all know a plum is a type of fruit. And a prune is just a dried plum, right? Well, yes and no. There is a difference that is worth exploring. In this article, you can find out more about both plums and prunes and their nutritional benefits.

Explanation of the confusion surrounding their identities

Let me first introduce plums. Plums are a type of stone fruit. This essentially means that they are from a family of fruits which contain a hard stone core. If you have ever enthusiastically bitten into a plum and nearly cracked a tooth, that is the stone in the centre. Other members of the stone fruit family include apricots, cherries and peaches. 

While it is true that prunes are dried plums, not all plums can be dried and transformed into prunes. The most common plums that are used to make prunes are the prunus domestica or European plum. The important factor here is whether or not the plum will ferment during the drying process. If it ferments when drying it cannot become a prune.

Is this just an arbitrary distinction? I mean how big could the difference between plums and prunes actually be? However, there are indeed different nutritional benefits to plums and prunes as they come from certain varieties with different characteristics.

The plum: Nature's sweet treat

Humans have purposefully cultivated plums for a long time, longer than any other fruit save the apple perhaps. Argued to be one of the first fruits to be domesticated. Although we often think of the plum as a purple fruit as that is the most widely available colour, plums also can be various other colours such as yellow, red, white or green. By far the most common plums in cultivation are the prunus domestica(European plum) and Japanese plum (prunus salicina). Japanese plums are larger and juicier than most other varieties. Combined with a longer shelf-life, it is no surprise therefore that this variety surpasses all others in the fresh food aisles of most supermarkets as the characteristic purple plums we are most familiar with. The taste of plums can range from sweet to sour. The skin is usually the most sour part of the fruit. 

Nutritional benefits of plums

There are lots of nutrients to be found in plums. Vitamins A, C and K are found in significant amounts. Also, there are natural antioxidants in plums, mainly phenolic mixes and anthocyanins,¹ not to mention the healthy fibre content that can aid digestion. 

Uses of plums

Plums show a high versatility and have been used for many different food products throughout cultures and times. Aside from being eaten whole, they can be made into jams, plum juice can be fermented to make plum wine and other alcoholic beverages. Salted or dried plums can be used as a snack and they can also be fashioned into plum dumplings. 

The prune: More than just a dried plum

While prunes are dried plums, they can only come from certain varieties of plums but not all plums can serve this function. The usual varieties are European or Japanese plums. The prune is wrinkly textured as a direct result of the dehydration required to produce it from the plum varieties. It is here that we observe another difference. Most plums that are eaten directly are of what one would call a clingstone variety. This means that the pit (stone) in the centre is not easily removable. The varieties utilised in prune production are typical of a freestone variety where the pit detaches from the fruit much more readily.

The cultivars, which is a fancy way of saying variety, of plums used most commonly are ‘improved French’, ‘Sutter’, ‘Tulare Giant’, ‘Moyer’, ‘Imperial’, ‘Italian’ and ‘Greengages’, 

Prune plums are visibly smaller and reach the markets earlier than those of typical plums. Prune plum varieties also are easier to grow as they are self-fertile and there is no requirement for cross-pollination. This makes growing them more efficient. In more recent times, since the early 2000’s there has been a push commercially, especially in the United States, to change the name of Prunes for marketing purposes. The name “prune” is believed to have too many negative associations tied to it such as being for the relief of constipation. This connection is not welcomed by some companies who have therefore tried rebranding to call them dried plums. I guess this is an accurate term and one that is starting to catch on.

Prunes will share many of the same nutrition content as regular plums, however, as there are only certain varieties used for prune making, they will contain the nutrients found in these specific cultivars.

Prunes contain a lot of fibre. Fibre makes up about 7% of its weight. They also contain sorbitol. Sorbitol is a sugar alcohol which is sixty percent as sweet as sugar but provides ⅓ of the calories.² Sorbitol has the effect of reducing constipation by drawing in water to the intestines and softening the stool, making it easier to pass. These two constituents combined make prunes have a significant laxative effect,³ the reason why it is used against constipation and why prunes have their association with reducing constipation. This is the case even with prune juice which happens to be devoid of any fibre after it undergoes filtration, something which would suggest a large role of sorbitol in this laxative effect. They are a good source of energy due to their simple sugar content. Despite this, they do not trigger a rapid rise in blood sugar levels due to the high fibre content which mediates a slower release of these carbohydrates. Prunes also share with many ‘normal’ plum varieties the presence of phenolic compounds⁴ which provide a natural antioxidant effect and can potentially provide some protection against chronic conditions such as heart disease and cancer. 

How prunes are made from plums

So I hope you have followed along nicely so far. Now that we know that prunes are produced from certain varieties of plum, the next question you may ask is how are they dried. What is the process they must undergo to become the wrinkly prunes that we are familiar with? There are many ways of drying prunes that have developed over time. From sun-drying, and air-drying to gas-drying. This can be the most expensive part of the production process to produce a finished prune. In California, for example, they use gas drying of prunes. The fruit is measured by a firmness tester to establish whether they are optimally ripe or not. This is usually ideal for harvest at the 3 to 4 pounds of pressure mark. Then they are picked and placed into large 1,000lbs bins and washed. The drying occurs in large drying tunnels where the actual drying takes place over an 18-22 hour period.⁵

Culinary uses of prunes

Prunes lend themselves towards being perfect snacks on the go. However, there are also many versatile uses for prunes and they have been used for making juice, in stews, dips and also in desserts such as cakes and cookies. Prunes are sweet with a slightly 

Tangy taste. The chewy texture is satisfying and fulfilling. They are an acquired taste, however, as some may find them to be too sweet or too strong for their liking. You will need to try them to see whether you like them or not. 

Summary

Hopefully, this article has helped you to learn more about the similarities and differences between plums and prunes. The main differences are related to taste and texture. The nutritional value is broadly shared between both plums and prunes. Indeed as we have learnt, prunes are made from certain plum varieties that are smaller than typical plums eaten whole. They are both nutritious options to include in any balanced diet, providing benefits such as fibre and antioxidants. It is advisable to enjoy plums or Prunes as part of a healthy lifestyle. There are so many ways they can be prepared- experiment and discover the ways you like them best and eat away!