I rarely eat raisins. Had not baked anything having them until last
week. I made several detours to the result, not something to write about
at this time. Let's say my recipe title has "globbylar clusters" in its
future. Anyway, back to raisins. I'd always thought of them as
dehydrated and wrinkled grapes.
I had bought a 12-ounce box of Sun-Maid raisins to use in my recipe.
The image shows green grapes and dark raisins. To my puzzlement, the
list of ingredients was "raisins". Hmm, I'd have thought "grapes". Sunmaid.com declares, "Made with nothing but grapes and California sunshine, ...".
I wondered how much shrinkage occurred from grapes to raisins. Also got curious about the process.
Overview of Raisins
"Grapes to Raisins Time Lapse - 50 Days【4K】"
shows drying using a fan, from different angles. The transition from
firm green grapes to wrinkled brown raisins is eye-catching.
"6 Different Types Of Raisins You Can Find In A Grocery Store"
provides overview--richly showing images and describing these raisin
types. Apparently, method of drying, temperature, and humidity affect
the final raisin colorations, which processors use for creating the
desired results.
"Sun-Maid Sun-Dried California Raisins" explains the terrain, climate, harvesting, and 14 to 20 days of sun-drying.
"Video: Raisin Processing and Packaging - How It Works"
takes up the grapes-to-raisins process from truck deliveries to
manufacturing facility. A few clips of mechanization are impressive, a
well-oiled machine. Sun-Maid does show products besides raisins, a
testament to their versatility over time.
DIY Grapes to Raisins
Some sites mention two to four days for grapes to become raisins,
much shorter than sun-drying or fan-blowing. You can DIY
grapes-to-raisins processing.
"How to Make Raisins"
explains three methods, with detailed steps and pix in sections titled
"Drying Grapes in the Sun", "Making Raisins in the Oven", and "Using a
Dehydrator". An unusual feature in the article is that each subtopic
title "travels" with its respective method.
"Here’s a Grape Idea – Make Your Own Raisins!" is a short article, but explicit with explanations and steps for the methods (dehydrator, oven). Overview excerpt:
the red and purple grapes will yield a darker raisin, the
green grapes a lighter version. Homemade raisins can come out plumper
and juicier with a flavor that's truer to that of the original fresh
grape, only more intense. Grapes are 80% water so it takes time to turn
them into raisins. ... The traditional way to make raisins is for them
to dry in the sun. The weather needs to be hot and dry. This takes 3 to 4
days, turning them frequently.
Grape and Raisin Water Content
The "Grape Idea" article, which mentions grapes being 80% water, nudged my curiosity about density.
"How Do You Raise a Raisin?"
states "about four and one-half pounds of fresh grapes to make one
pound of raisins." BTW, the article has engaging info and illustrations
that look intended for younger audiences, but appealing enough for
grownups. Look for explanation about raisins drying in the sun. It
actually complements the Sun-Maid video about harvesting and drying the
grapes.
"Comparing the nutritional content of Grapes and Raisins"
states "A raw grape is on average 80.54% water and a raisin is 15.43%."
This article is detail-heavy about nutrients and comparisons between
grapes and raisins. Let's say it makes for dry reading. A factoid
correlates with the Sun-Maid video WRT grape type--"Typically it is of
the green seedless variety grown mainly in California."
"Why Grapes Cost More Than Raisins. What Eats Jellyfish."
has grapes/raisins info. Ignore the jellyfish segment, although the
article writer might have thought a tie-in about water percentages made
sense. More reiteration about types of grapes, grape/raisin ratios, with
a mention about regulation.
From four to four-and-a-half pounds of raisin grapes make a
pound of raisins. There’s actually a raisin commission in California
that keeps track of the size of the harvest and the number of boxed
raisins held in storage. They control the number of boxes released to
market, again, to avoid droughts and gluts on the shelves.
California Raisin Advisory Board (CALRAB)
The California raisin commission mentioned in the previous subtopic greatly influenced the popularity of raisins in the 1980s.
"The Story of The California Raisins" describes the Board's role with promoting raisins with claymation
It all began in the mid-80s when the California Raisin
Advisory Board (CALRAB) started to look for a way to make raisins a cool
thing to eat. After few failed attempts, the CALRAB called Oscar-winner
Will Vinton [who passed away in 2018] to create clay animation figures
for a commercial using Marvin Gaye’s 86 hit “I Heard It Through the
Grapevine”.
Plumping Raisins
While Googling about raisins, I ran across topics for "plumping"
(rehydrating) raisins for recipes. I had visualized maybe fewer or
smoother wrinkles, maybe the raisins becoming bigger. Nothing like
trying a process or two to see end results.
"How to Plump Raisins"
intrigued me for seeming ease of the microwave technique of 1 cup of
raisins and 1 tablespoon of water. After a couple of two-minute bouts of
microwaving, using tight-resting lid to single-layer raisins on plate, I
wasn't impressed. Not only did the raisins look unchanged, they
weighted slightly less, indicating evaporation.
Later, I tried microwaving a different batch, immersing some raisins
with plenty of water for a couple of minutes. The weight increased by
about 17%. A few hours later, I gave those raisins another zap session,
with additional water. Ultimately, they weighed more by another 18%.
(Initial weight: 2 oz; second weight, 2.37 oz; final weight: 2.75 oz)
Comparing one ounce of out-of-box raisins to equivalent of plumped
raisins (half of initial 2 ounces), the image shows size difference.
Eh,.the time and effort hardly seems worth the effort. Also, I infer
that some flavor and nutrients floated out in the microwaved water,
maybe suitable for breads or muffins, maybe not for no-water cooky
recipes.
Circling Back to DIY Raisins
Considering the yield of raisins after DIY drying, and the time,
effort, and watchfulness required, it seems reasonable to leave the
drying process to the pros (grape growers, harvesters, and
raisin-product facilities). They have the infrastructure
