Batch and lot number: the detail that decides whether your pack is affected
A recall almost never covers an entire product, only certain lots. That is why every notice states a number, and why that number decides whether the pack at home is affected.
What a lot is
A lot is the set of sales units of a food produced, manufactured or packaged under practically identical conditions. The lot is determined by the producer, the manufacturer, the packer, or the first seller established in the country concerned.
The European basis
The obligation goes back to Directive 2011/91/EU on indications or marks identifying the lot to which a foodstuff belongs. It applies across the Union, but as a directive it is transposed into national law by each member state. The principle is the same everywhere; the name of the national rule is not.
The letter L
The indication consists of letters, of digits, or of a combination of both. The letter L has to precede it where the indication is not clearly distinguishable from the other particulars on the pack. That is why many packs show an L followed by a sequence of digits.
The rules also require the indication to be easily visible, clearly legible and indelible.
How Germany transposed it
In Germany the rule is the Los-Kennzeichnungs-Verordnung (LKV), in force since 1 July 1993. Under § 1, food may be placed on the market only where it carries an indication showing the lot it belongs to. § 3 sets the requirement that the indication be easily visible, clearly legible and indelible.
How Austria transposed it
Austria transposes the same directive through the Loskennzeichnungsverordnung (LKVO), in force since 13 December 2014. The substance matches the German rule; the name of the legal basis differs.
When no lot number appears on the pack
The rules provide for exemptions. The most important one in practice: where the food carries the best-before date or the use-by date unencrypted, stating at least the day and the month in that order, the obligation to give a lot number falls away. The date then performs the function of the lot marking.
Further exemptions cover, among others, packaging whose largest single surface is smaller than 10 square centimetres, individual portions of ice cream, and food packed at the point of sale on the request of the buyer.
This explains a common observation: some packs carry no L at all. In such cases a recall notice usually gives the best-before date as the identifying detail instead.
On other products the indication is called a batch number
The lot number concerns food. On technical products, cosmetics or toys, packs carry a batch number, a serial number or a model number instead. The recall notice itself states which indication is the relevant one.
Where the indication is usually printed
The indication is normally on the prepacked unit or on packaging attached to it, often close to the best-before date, on the base of the pack, along the crimp seam or on the lid.
Why the number is decisive in a recall
A notice does not normally name a product on its own, but a product in combination with specific lots or batches. The same product from a different batch may not be covered by the measure at all. Without the number the comparison cannot be made.