...if you want to make gel balls with agar, you have to do it before the mixture gets cold, generally you use a tall, narrow glass/jar, fill it with very cold oil and proceed to drip the still hot mixture into it, the difference in temperature will cause the spheres to gel instantly (agar gels become "solid" below 35 degrees). The main difference compared to spherification is that the balls will have a single consistency from outside to inside.

If, however, you do a real spherification (eye that can be direct or inverse depending on whether you put the alginate in the liquid to be spherified and the lactate in the liquid you use only to carry out the reaction or vice versa) the gelation reaction will take place only in the external part of the spheres, which will therefore have a liquid heart (especially in the case of inverse spherification, because in the direct case the alginate continues to react until the whole sphere "solidifies" if you don't use it relatively soon), in these two cases (sf. Direct or inverse) it will be necessary to degas the mixture (vacuum-packed or, if desired, using a very fine mesh strainer or food filter paper) or let it rest in the fridge until it has degassed (even 24 hours depending on how good you were at not incorporating air with the blender), all this provided that you do not want floating spheres instead (such as Campari/Aperol ones for a spherical spritz, which is instead preferred when they float) in this in this case you will not have to degas the liquid to be spherified, so as to ensure that the spheres float due to the air contained