I ended my column on roasted garlic and garlic oil with a strong warning about the danger of botulism poisoning from raw garlic-infused oil. Let’s pick up where I left off.
Usually it’s fairly easy to tell when food is spoiled. Botulism isn’t obvious, however – the food can look and smell normal. This is why home canning guidelines are so strict. And with raw garlic oil, the heat used in canning which might kill the micro-organisms isn’t even present.
But garlic preserved in oil is readily available commercially – why is that safe? If you read the label, in addition to garlic and oil, commercial producers use additives to lower the pH, or acidity, of the product to a level which the toxin can’t grow in.
Is there a way to make and use fresh garlic oil safely at home? Yes, if you’re careful about making and storing it. Peel and wash the garlic you wish to use. Dry it thoroughly. Cut off the root end, and slice lengthwise or chop the garlic, and stir it into the olive (or other oil) you wish to use. Refrigerate immediately, and allow to infuse until you get the desired level of garlic flavor. Garlic is powerful stuff; this may not take long. Strain the garlic out if you want to halt the flavoring process, or leave it in if, like me, you feel it’s difficult to have too much garlic. Keep it refrigerated at all times, and use it up within a week. Don’t be tempted to keep it longer than that. Make small batches more frequently if you like to have it on hand.
Whether garlic oil is a by-product of making roasted garlic or made freshly, it’s a great flavoring.
So are other flavored oils, and the sky’s the limit when creating them. You can flavor oils with vegetables, herbs, spices, and that most luxurious of ingredients, truffles.
Some oils are good made with a base of olive oil, while some are better made with a more neutral oil like grapeseed or sunflower. For health reasons, I don’t recommend “vegetable”, soy, corn, or canola oil. Let’s start with some pungent oils other than garlic.
Shallots, horseradish, and ginger oil are simple to make. Simply wash, dry, and peel them, and mince finely. You can do this by hand or use a mini-food processor. I prefer to do it by hand because the volume isn’t great and then all that needs washing up is a knife and a cutting board. It only takes two tablespoons of mince to flavor two cups of oil. All of these are best steeped in a neutral rather than olive oil. Mix them together well in a clean jar and refrigerate immediately. Your oil will be ready to use in a couple of hours.
What about herbs? For resinous herbs like thyme, rosemary, and oregano, it’s a simple matter of stripping the leaves from the stems and mincing them. You’ll need much more – a full cup – in the way of herbs per two cups of oil, so you may want to use a food processor here. Mix the herbs well with your chosen neutral oil, and leave at room temperature for a couple of hours before refrigerating. Strain before using.
For “tender”, or what the French call “fine” herbs, it’s a bit more time consuming. Leave basil, parsley, cilantro, or mint on their stems and blanch them in boiling water for 15 seconds. Immediately remove and plunge them into cold water to stop further cooking. Drain them and dry thoroughly. Measure them and add an equal amount of olive oil; blend them together to form a smooth paste. You can use a food processor, but it won’t make as smooth a paste as a blender will. (This is a good job for an immersion blender.) Measure the herb paste, and mix three times as much plain olive oil into it. This should infuse longer, at least overnight and perhaps 24 hours, at room temperature. Strain, and refrigerate. It can be kept a good week.
What about spice-infused oils? They couldn’t be easier. In all cases, use ground spices; some suggestions would be caraway, cardamom, cinnamon, cumin, curry, fennel, mustard, paprika. What about wasabi? (Wow-sabi?) All that’s needed is to make a slurry of spice with enough water to create a smooth paste, beginning with three tablespoons of spice and one of water. If it’s too dry, add more water in tiny increments until you get the right consistency. Now mix the spice slurry with two cups of neutral oil in a clean jar and leave at room temperature. Stir or shake occasionally. After two days, stop agitating the mixture and allow the spices to settle at the bottom of the jar. Ladle off the oil from the top rather than straining it. These oils keep well at room temperature for up to six months; there’s no need to refrigerate them.
Truffle oil is popular, and widely available commercially. Some brands are better than others, but you can make your own so you know how much truffle goes into it. Use either fresh or canned black or white truffles; white make the more flavorful oil, in my opinion. For two medium truffles, blend them to a smooth purée with one cup of neutral oil and either ¼ cup truffle juice if using canned or ¼ cup port if fresh. Don’t strain this one! Store in the refrigerator for up to two weeks.
How to use these oils? Sauté in them, marinate in them, make mayonnaise or salad dressing, enrich soups, drizzle on cooked meats or vegetables, or use them as a dip for bread… those are just a few general suggestions. Let me know what specifics you come up with.
(Photo: Jean Scheijen)