While not 100% there yet, this is our in-progress recipe for a clone of the bag-in-a-box sauce currently in use at Shakey's:
20 oz (by weight) SuperDolce Super Sweet, Super Heavy Pizza Sauce (Stanislaus Food Products, Beautiful Downtown Modesto, CA)
1/2 teaspoon dried minced onion
1/2 teaspoon basil leaves
1/4 teaspoon ground oregano
1/4 teaspoon garlic powder
4 Tablespoons dextrose
3 Tablespoons Michele Chiarlo Barbera D'Asti Le Orme wine
1/8 cup water
The water, minced onion, basil and garlic are mixed in a saucepan and cooked until the dried onion is translucent. After letting the mixture cool, the wine, ground oregano, and dextrose is added and stirred. Finally, the pizza sauce is added to the saucepan and everything is thoroughly mixed. The mixture is then placed in a quart-size reclosable plastic storage bag and left in the refrigerator for two days, being periodically agitated by hand to mix the ingredients.
The pizza sauce already contains salt and citric acid. Adding salt and powdered citric acid was not necessary. Many sauces you buy today lists "natural flavor" as an ingredient. As mentioned in a previous post, we think whatever flavor(s) they are adding tastes a lot like wine. Barbera D'Asti wine was the best match out of several wines we tried. This wine was mentioned in a lot of Internet posts as being a good accompaniment to pizza.http://www.chiarlo.it/english/vini/barbera_d_asti/leorme/index.htm
A few remarks about the dry ingredients. After trying Spice Islands and Badia ground oregano, we think the Badia (Miami, FL) is a better match. It is a Hispanic market food item. We selected Lisy (Miami, FL) garlic powder as the best match. The closest match of basil leaves were the supermarket house brands made by McCormick; we bought it under the Hannaford label. The closest match of minced onions were the supermarket house brands produced by the ACH Food Companies, bought under the Food Lion label. The dextrose was bought from a nearby beer/wine home brewing store. Powdered citric acid, used in early experiments and with an Escalon tomato product, was purchased in a big international foods supermarket catering to Asian, Indian, and Hispanic customers.
The hardest part is finding a canned tomato product that duplicates the tomato paste and water mixture that they start with in the sauce factory. We literally tried every thick tomato product available at local supermarkets, as well as at Whole Foods, Trader Joe's, and Super Walmart, including the new Classico line. We even obtained a #10 can of Heinz' current version of 1.06 specific gravity tomato puree. None of these products had the tomato flavor profile of the current Shakey's sauce. We now actually prefer the taste of this SuperDolce pizza sauce. This sauce has a coarser finish than the Shakey's sauce and can't be blended with much liquid because, according to Stanislaus,
"Of course, there is no such thing as a free lunch. The tradeoff for SuperDolce®’s super sweet flavor is that it contains less moisture-retaining pectin, so it won’t "hold" as much added moisture as its cousin, Saporito® Super Heavy Pizza Sauce".
I believe the best match will come from one of the California fresh pack tomato puree or pizza sauce foodservice products. I did try a batch using Stanislaus Full Red tomato paste, but it was not a good match. The problem for us is that while we have two local foodservice distributors that will sell cash-and-carry, they only sell in full case lots. We will price out a shipment from Penn Mac. We no longer have any samples of genuine Shakey's sauce, and it will be a few months before we receive anymore. We can't place any other common herbs or spices in this sauce other than those mentioned. Some of the early heat we experienced turned out coming from the pepperoni drippings. It is possible there are additional herbs and spices added to the mix, or it may just be some "natural flavors" turned out by such fine folks as Kerry Americas and Wild Flavors.
Again, the criteria we are using is to clone the sauce currently used at the corporate-owned locations in California. We are testing against actual samples of baked pizza and sauce.
If the (legal) bookmakers in England were taking bets on who was making Shakey's sauce, I would put a few pounds Sterling down on Neil Jones Food Company/San Benito.