[Problem] To produce, with a method that is low-cost and has a low environmental impact, a cloudiness-inhibiting agent that is highly safe and has no taste which has a cloudiness-inhibiting effect in a tea beverage. Also, to make effective use of yeast cell body residue produced as a byproduct of yeast extract.[Means for Solving the Problem] Yeast cell body residue remaining after removing useful extract from yeast is suspended in water and heated, after which the suspension is subjected to centrifugation to obtain a supernatant. This fraction has an amount of RNA content per solid content of the yeast extract of at least 50 wt%, dietary fiber content of at least 5 wt%, and protein content of at least 10 wt%. Mannan content is at least 60 wt% of the dietary fiber. This fraction can be used to inhibit cloudiness for a tea beverage.