I thought I hated guacamole until about 5 years ago when I was coerced into trying it for the first time as an adult and, since then, I’ve been making up for lost time! Often, I whip up a couple of easy cheese and guacamole tortilla wraps for lunch, and I had gotten to wondering why prepackaged guacamole doesn’t turn brown? I mean, the Frankenfood guacamole from Taco Bell, God knows what they put in there, but I’d bought the decent 95% avocado kind, with the following ingredients list:
Hass Avocado, Salt, Evaporated Cane Juice, Red Bell Pepper, Onion Powder, Garlic Powder, Ascorbic Acid (Vitamin C), Minced Onion, Citric Acid, Xanthan Gum, Jalapeno Pepper, Cilantro.
Sure enough, I’ve confirmed my initial suspicions: the ascorbic acid/vitamin C is what keeps this guac from turning brown (even after one… or even two… weeks in the fridge). Avocados contain an enzyme that makes them brown badly shortly after being exposed to air (apples and potatoes also contain the enzyme). One way of keeping them from turning brown is to keep the avocado from touching the air: people do this at home by tightly covering the dish, and manufacturers may vacuum the air out of guac packages and/or fill them with nitrogen gas instead.
But you can also lower and slow the activity of the brown-making enzyme by keeping the guacamole cold and lowering its pH level (that is, adding something acidic). No weird chemicals or preservatives are required – ascorbic acid/vitamin C will do the job. It’s a vital nutrient that we already consume frequently anyways, and vitamin C is not something that you can easily overdo.
So if you want to keep guacamole from turning brown, be glad to know that it doesn’t require any weird additives after all! Just give ascorbic acid a try. You can find ascorbic acid/vitamin C powder in the spices or canning sections of grocery stores, or sold as a vitamin at supplement shops.
Try adding 1/8th or 1/4 of a teaspoon to each batch of homemade guac. And you might want to leave out your lemon or lime juice until you taste test – the ascorbic acid will impart a similar tang. Happy dipping!