How to preserve ube jam

In this brief guide, we are going to answer the question “how to preserve ube jam” and discuss the different methods used to preserve ube jam.

How to preserve ube jam?

Ube jam is preserved by: 

  • Refrigerating 
  • Freezing

What is ube jam?

Ube jam, also known as ube halaya or purple yam jam in English, is a popular food in the Philippines. Ube jam is made by cooking mashed purple yams with dairy and sugar and other ingredients that vary according to the recipe. Dioscorea alata is the scientific name of the Ube. It is a grayish-brown skin rooted crop. It is planted from months of May to December and its texture becomes soft when cooked (1).

Ube is a great source of potassium and vitamin C. It is also rich in antioxidants including anthocyanins which give them their vibrant hue and may help reduce blood pressure and blood sugar levels (1).

Ube jam has a short shelf-life since it is a dish made with starchy yams incorporated with sugar and dairy. All these ingredients attract mold and bacteria. So it is necessary to use the correct techniques to preserve ube jam.

Ube jam must not be kept at room temperature. Always refrigerate or freeze the jam as soon as it reaches room temperature.

How to refrigerate ube jam for refrigeration

Refrigerating will preserve ube jam only for about 3 days. For a longer shelf-life, it is recommended to freeze the jam.

If you are refrigerating ube jam, packed into sealed bottles, they may last for about a week in the fridge.

If you are refrigerating ube jam in a bowl or tray (made as a pudding), it will only last for about 3 days. Make sure to cover the bowl with a cling wrap. This prevents moisture from spoiling the ube jam.

How to freeze ube jam for preservation

Freezing will preserve ube jam longer than refrigerating.

If frozen in sealed bottles, ube jam will preserve for about 3 months.

If frozen in a bowl or tray, it will only last for about a month. Once again, make sure to cover the bowl with a cling wrap to prevent moisture and ice crystals from forming.

Frozen ube jam must be thawed by placing it in the fridge for a few hours. After thawing it is best to use the ube jam within 5 days. It can be refrozen but there will be a loss of quality.

During freezing, a proportion of the water in the jam samples changes from liquid to

solid to form ice crystals; as the samples are thawed, the retrogradation process of starches forces water out of the jam structure, and the separated water is visible. In addition, the jam´s texture changes (3).

Tips for preserving ube jam

  • Allow the ube jam to cool down to room temperature before refrigerating or freezing.
  • Packing the jam into sterilized jars or trays will prolong the shelf-life. They can be sterilized using a boiling water bath or in an oven.
  • Cover the ube jam well or freeze it in sealed bottles. This will prevent spoilage and extend the shelf life.
  • Once frozen ube jam is thawed, try to use it within 5 days at most. Try not to refreeze thawed ube jam.
  • Freeze the ube jam in small jars. This way you can thaw one jar at a time.
  • When freezing ube jam, store it away from meat, fish, and vegetables in the freezer. This will prevent any possible cross-contamination.

How is ube jam made?

Jam is defined as a semisolid food made from not less than 45% (by weight) fruit and 55% (by weight) sugar. This substrate is concentrated to 65% or above soluble solids. Flavoring and coloring agents may be added. Pectin and acid may be added to overcome the deficiencies that occur in the fruit itself. Ube contains water-soluble pectin, which enables its use in making jams and jellies. The process consists of cooking a mixture of 20.7% ube, 45% sugar, 34% water, and 0.3% citric acid until solids content of 68° Brix was reached (2).

There are a few different methods to make ube jam, but they all use the same basic ingredients: purple yams, milk (this can be either condensed milk, coconut milk, or a mixture of both), and sugar.

In a study, ube jam was prepared using 1 kg of sweet potato pulp (ube pulp prepared from previous washed and sterilized tubers), 900 g of sugar, 10 g of citric acid and 5 g of pectin. After cooking, the jam was filled into sterilized jars and stored for 60 days (4).

Ube jam is typically molded into trays and allowed to set, but you can also pack it in jars like any other jam.

Making ube jam at home is time-consuming, but the results are worth it. If you want to try making ube jam at home, check out this recipe.

How to use leftover ube jam?

If you have made an excess of ube jam, there are quite a few ways to use this delicious dish.

As a jam: As the name implies, ube jam can be spread on toast just like any other jam.

As a pudding: You can also eat the jam by itself as a dessert. 

As a base for ice cream: If you want to try making a new flavor of ice cream, why not try ube jam as a base. The purple of the ube jam will make the ice look vibrant.

Make ube frosting: Ube jam can be used as a frosting for an ube cake. It can be used as a jam on cheesecake as well.

In bread rolls: You can make an ube jam filing for your bread rolls.

How to know if ube jam is spoiled

Regardless of the storage method, ube jam can spoil. Always check for the following sign before eating preserved jam:

  • Smell: if the ube jam smells off or rancid, discard it.
  • Appearance: if you observe any mold growth of spots, discord the jam.

Other FAQs about Jam that you may be interested in.

How to preserve jam

Are jam and jelly the same thing?

Can you get sick from eating moldy jam?

Conclusion

In this brief guide, we answered the question “how to preserve ube jam” and discussed the method to refrigerate and freeze ube jam. We also discussed the ways to use left-ver ube jam and how to identify if ube jam has gone bad

If you have any questions or comments, please let us know.

References

  1. Van Tiu, Q. The Future Is Now: Promoting and Selling the Philippines’ Ube in the World Market. Int J Progr Res Sci Eng, 2021, 2, 58-60. 
  2. Sur, Rahul, et al. Standardization of recipes for preparation of sweet potato jam. J Pharmacog Phytochem, 2020, 9, 580-584.
  3. Javanmard, Marjan, et al. Characteristics of gelling agent substituted fruit jam: studies on the textural, optical, physicochemical and sensory properties. Int J Food Sci Technol, 2012, 47, 1808-1818.
  4. Devi, Chhama, Laureate Hynniewta, and Surajit Mitra. Quality evaluation and preparation of jam from sweet potato cultivars. Int. J. Curr. Microbiol. App. Sci, 2017, 6, 1485-1492.