In a large saucepan, combine the water, vinegar, sugar, garlic, jalapeños, bay leaves, crushed red pepper, salt, peppercorns and allspice berries and bring to a boil to dissolve the sugar. Add the shrimp and cook, stirring, for 1 minute. Transfer the shrimp and liquid to a large bowl and let cool to room temperature. If you can, accelerate this process by placing bowl out in the snow, or place in the freezer for about 15 minutes. Then cover and refrigerate for 8 to 10 hours.