Karl’s Valley of Heart’s Delight White Nectarine Jam

I have just updated my wife’s research site—The Silicon Valley Cultures Project—after several years of dormancy. There are many anthropologist who are followers of my blog and I wanted to spread the word. Jan suggested that I make a dish to celebrate and justify the announcement on a food blog.

My wife has been studying the life and the international denizens of the area called Silicon Valley for the last 28 years. This research has resulted in four books and many articles and papers. Before there was silicon in this valley it was called the Valley of Heart’s Delight for all of the stone fruit orchards—which have since been chopped down and replaced with high density housing and tilt-ups.

Note: The site update includes links to: 1 new book, 5 new articles, and 26 new master’s theses related to the SVCP.

Last week, my daughter Miriam went to a farmer’s market and bought 10 pounds of white nectarines. After eating two pounds, she realized that there was no way she could eat them all before they went bad on her.  To her credit, she cut them up and froze them before asking, “Please daddy, make me some jam.” This is called “networking”—a very Silicon Valley skill.

Karl’s Valley of Heart’s Delight White Nectarine Jam

Ingredients

8 lbs. white nectarines (about 16 cups)
1 tsp. Kosher salt

6 cups sugar
1 cup water
2 large lemons zest and juice

Directions

1. Sterilize a dozen 12 oz. canning jars and lids.

2. Rinse and seed the nectarines.

Tip: I am writing this recipe as if you are starting with fresh fruit—although I started with two large bags of frozen fruit. If you are starting with fresh fruit, you may blanch and peel the fruit as well if you wish.

Note: Since my daughter had cut up and frozen the fruit I was married to keeping the skins. To prevent having big chunks of skin in my jam, I decided to run the fruit through a standing blender and then sieve the results. When I was done, I discovered that the new high powered blender that Miriam had bought me left very little peel to remove. In the end, I could have saved myself some labor.

3. Slice each nectarine into medium small pieces.

4. Put the nectarines in your jam pot and sprinkle the salt and half the sugar over them, toss gently to mix.

Tip: The salt and sugar will break down the cell walls and draw out the juices from the fruit.

Note: If you wish to have a perfectly smooth jam, you may blend the fruit in batches in a standing blender before adding the slurry to the pot with all of the sugar and skip the macerating step.

5. Let the nectarines sit, tossing occasionally to redistribute the sugar syrup, for ½-1 hour.

Tip: After the fruit have macerated to your liking, proceed to the next step.

6. Add the water and the rest of the sugar to the pot.

Tip: As you cook the jam some of the liquid in the pot evaporates away. This water simply  replaces that loss.

Note: For my other peach jams I used 5 cups of sugar for 10 cups of pulp. This was still a bit too sweet. For this jam, I cut the sugar down to 6 cups to 16 cups of pulp.

7. Zest the lemon and place the zest in the jam pot.

Tip: My new zester cuts much deeper and takes fine shreds of zest and pith. This is important, because you need the lemon pith for the pectin within.

8. Juice the lemons and add it and the water to the pot.

Tip: The lemon juice prevents your jam from oxidizing and turning dark. It also lowers the jam’s Ph which inhibits bacterial growth—extending the shelf life of your preserve.

9. Bring the fruit mixture to a boil.

Tip: I have read several recipes that insist that you should make jam only four cups of pulp at a time. I have never had any difficulties in making patches of 23 cups at a time—16 cups pulp, 1 cup water, and 6 cups sugar.

10. Cook the fruit and sugar over medium low heat for 30-40 minutes over a medium heat.

Tip: If you wish you may stop cooking your jam after 10 minutes—you will get a “fresher” fruit flavor, but to get the jam to jell properly you will need to add as much as five tablespoons of commercial pectin. Cook the jam another five minutes after adding the pectin.

Note: I like to cook my jams for an extended period—30-40 minutes—it caramelizes more of the sugars and give the jam a deeper flavor. The longer cook also evaporates more of the liquid and the jam will either jell on its own or require adding less commercial pectin to set up your jam.

11. Simmer the jam until it starts to jell to your liking.

Tip: This can be anywhere from 30 minutes to  an hour—depending on how juicy your fruit was and exactly how high you have your heat. You want the heat high enough to have a serious simmer, but not so high that your jam boils over.

Note: To test your jams readiness, take a spoon of the jam and place on a plate next to an ice cube. After a few minutes pour the jam back into the pot. When it flows off in a sheet—rather than a thin stream— the jam is ready.

12. Pour the jam into sterilized jars and loose tighten the lids.

Note: Put the lids on the jars and tighten them down. Back the lids off about an eight of a turn so that they are “tight/loose.” This allows the air to escape—when you reheat the jars in a water bath—but does not let the water leak into the jars.

13. Place the jam jars in a water bath and boil for 20-30 minutes.

Tip: Since my wife is giving these away—possible over months—I wanted to extend the shelf life of this jam—this is not usually an issue at my house. Put the partially sealed jars in a water bath and boil them for another half hour to finish the “canning” process.

14. Remove the jars and fully tighten the lids.

15. Allow them to cool completely before storing.

Tip: The jam should last for a year on a pantry shelf, but you will be lucky if it sees the next month.