What she is saying is that fresh lemon juice has more acid than bottled lemon juice (expressed as grams of citric acid per 100 grams of juice). If true, then she is correct that using fresh lemon juice in your recipes would yield an equal or lower pH than an equivalent volume of bottled lemon juice. I imagine the FDA chose a minimum of 4.5% (as citric acid) because it represents the bottom of the range found in fresh lemon juice. Setting rules based on the minimum allowed acidity is always safer. Personally, I use pure crystalline citric acid, which is consistent in acidity and has less of an effect on taste. TomNJ

Linda Lou, For what its worth, I asked the local wine hobby supplier to find out if their acid blend has a comparable acidity to citric alone, and she told me that the two other acids are granulated just like the citric. The drying and granulation process is the same. The tarteric acid she sells is not a powder like cream of tarter. She also used a pH test meter and made a solution of water (distilled) and mixed an exact amount of citric acid, and compared that with the same amount of acid blend and water. She saw no difference in acidity, and when each was diluted, they both appeared to be the same equal levels even after several dilutions and mixings of more water. Her granulated acid source is a major manufacturer of the granulated acids, and even though one is a tarteric and the other is malic, they all have the same acidity when mixed with the same water. The local supplier actually buys the granulated products seperatly and blends one third by weight with the other two. The actual amount of each acid might vary slightly, but this has little to no effect on the final acidity, only a slight flavor difference. I have used a few cider vinegars at 7%. Also, I still have 20% distilled vinegar here as well, and use that in canning mixtures where adding more water is not acceptable.

The type of lemon juice in jam is not an issue because jams are already acid products and the lemon juice serves other purposes (acid for pectin formation, flavor). So you can use fresh or bottled, whatever suits. The exception would be pepper jellies, which generally call for vinegar as the acid; there it's needed to compensate for the low-acid peppers in the mixture. Bottled lemon juice is standardized, so yes, in that way it's comparable to commercial vinegars. Fresh lemon juice, on the other hand, will vary considerably in acidity depending upon variety, season, growing conditions, degree of ripeness when picked, etc. That's why bottled lemon juice is specified in recipes like marinated peppers. For consistently safe results it's important to have assurance of sufficient acidity. Bottled lemon juice (and bottled lime juice) are more acid than vinegar. Therefore, whenever a canning recipe calls for vinegar, you could safely replace it with bottled lemon or lime juice. However, if a recipe specifically calls for bottled lemon juice don't substitute vinegar, as it's a weaker acid. Carol

This is our hands-down favorite with Meyers. Must be served with lots of softly-whipped, organic heavy cream - divine! Lemon Sponge Pudding Cake This is a lovely light dessert. All the ingredients are mixed in one bowl, but something magic happens in the oven: The batter separates into two layers, a creamy lemon pudding on the bottom, a light sponge cake on top. If you want to make a double recipe, it does NOT double when baking. Make a double recipe, but divide into two 1-qt stainless steel bowls or soufflé dishes when baking. INGREDIENTS 1/2 cup sugar 1/8 teaspoon salt (optional) 2 Tblsp all-purpose flour 1/3 cup Meyer lemon juice or 2 Tbls grocery store lemon juice Finely grated zest of 1/2 lemon 2 eggs, separated 1 cup milk Whipped cream, lightly sweetened INSTRUCTIONS Preheat the oven to 350 degrees. Butter (or spray with a canola cooking spray) a 1-quart baking dish or stainless steel mixing bowl. Get out a slightly larger pan, at least 2 inches deep, that will hold the pan(s) comfortably. Combine sugar, salt and flour in a mixing bowl; stir to blend. Add the beaten egg yolks with the milk. Add the lemon juice and zest and stir until thoroughly blended. Beat the egg whites in a bowl until stiff but not dry. Fold the beaten egg whites into the lemon mixture. Pour into the prepared baking dish. Set the dish in the larger pan and pour in hot water to come halfway up the sides of the baking dish. Bake for 40-45 minutes, until the top is lightly browned and just begins to crack. Serve warm or chilled, topped with whipped cream. Serves 4-5