In the trade in products without individuality and sold by quantity, specificity may be lost if a target object is stored together with inventory items after delivery to a buyer. However, if the target object can be identified by uniquely associating it with an individual delivery, then its specificity can be maintained even after storage with other inventory items.
Such an arrangement would allow the seller to achieve proportionate control even for items sold only by quantity. This arrangement would also permit the seller to hold collateral, including those products paid for, until the aggregate collateral reaches the total amount sold.
However, to justify this conclusion, I think it is necessary to consider whether to use the concept of aggregation. Furthermore, it is necessary to review the concept of "within normal business".