Question: Which two countries are where the soft serve dairy product originated between ?

text: List of dairy products
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This is a list of dairy products. A dairy product is food produced from the milk of mammals. A production plant for the processing of milk is called a dairy or a dairy factory. Dairy farming is a class of agricultural, or an animal husbandry, enterprise, for long-term production of milk, usually from dairy cows but also from goats, sheep and camels, which may be either processed on-site or transported to a dairy factory for processing and eventual retail sale.
Name Origin Description
Sarasson France A French dairy product resembling cream cheese or fromage blanc made from buttermilk
Semifreddo Italy A class of semi-frozen desserts , typically ice-cream cakes , semi-frozen custards , and certain fruit tarts . It has the texture of frozen mousse because it is usually produced by uniting two equal parts of ice cream and whipped cream
Sergem Tibet A Tibetan food made from milk once the butter from the milk is extracted . It is then put in a vessel and heated and when it is about to boil , sour liquid call chakeu is add and this leads to the separation of sergem from that milk
Sheep milk  Also known as ewe 's milk , it is the milk of domestic sheep . Though not widely drunk in any modern culture , sheep 's milk is commonly used to make cultured dairy products
Shrikhand India An Indian sweet dish made of strained yogurt . It is one of the main desserts in Maharashtrian cuisine and Gujarati cuisine
Skorup  Kajmak that is matured in dried animal skin sacks is called skorup
Skyr Iceland An Icelandic cultured dairy product , similar to strained yogurt . It has been a part of Icelandic cuisine for over a thousand years
Smetana Central and Eastern Europe A range of sour creams from Central and Eastern Europe . It is a dairy product produced by souring heavy cream
Snow cream  A cream-based dessert with one or more flavoring agents added or dessert in which snow is mixed with a sweetened dairy-based liquid to make an ice cream substitute
So Japan A type of dairy product that was made in Japan between 7th and 10th centuries . So was made from layers of milk skin
Soft serve United States A type of ice cream that is softer than regular ice cream , as a result of air being introduced during freezing . Soft serve ice cream has been sold commercially since the late 1930s
Sour cream  Obtained by fermenting a regular cream with certain kinds of lactic acid bacteria . The bacterial culture , which is introduced either deliberately or naturally , sours and thickens the cream
Soured milk  Produced from the acidification of milk . It is not the same as spoiled milk that has soured naturally and which may contain toxins . Acidification , which gives the milk a tart taste , is achieved either through the addition of an acid , such as lemon juice or vinegar , or through bacterial fermentation
Spaghettieis Mannheim , Germany A German ice cream made to look like a plate of spaghetti . It was created by Dario Fontanella in the late 1960s in Mannheim , Germany
Strained yogurt  Yogurt which has been strained in a cloth or paper bag or filter to remove the whey , giving a consistency between that of yogurt and cheese , while preserving yogurt 's distinctive sour taste . Pictured is strained yogurt with olive oil
Súrmjólk Iceland A cultured milk product , or a type of yogurt . It is made from either whole or semi-skimmed milk and various flavorings are sometimes added