Plastic Cell Cup Strips

Plastic royal jelly cell cup strips are production items in which many artificial queen cells (cell cups) are moulded side by side on a single plastic strip, which is fitted to the bars of a collection frame. The bees feed the young larvae grafted into these cups as if they were future queens and fill the cups with plenty of jelly; the jelly is collected about three days later. The strips can be washed and reused many times and make for fast work, but if they are not kept odourless and clean, acceptance drops quickly.

What is a plastic cell cup strip?

A cell cup (queen cup, queen cell cup) is a small cup that imitates the queen cell base bees naturally build at the edge of the comb. In queen rearing, cups are mostly fitted individually to holders. In royal jelly production, however, far more cups are used and the work is repeated every three days, so joining the cups in strips saves a great deal of time.

A plastic strip consists of dozens of evenly spaced cups arranged along a bar. The strip is slid onto a bar of the collection frame and fixed with a clip or a thin layer of wax. During grafting and harvest the strip is handled as a single unit.

Plastic strip or individual cups?

In queen rearing, strips are rarely used because ripe cells must be distributed one by one. In royal jelly production this drawback disappears, since the cups are harvested before they are ever capped.

How do you choose a good plastic cell cup strip?

• Material: Food-grade, odourless plastic. A strip with a sharp chemical smell can cause problems for a long time, even after the bees have cleaned it.
• Cup size: The inner diameter and depth should be close to those of a natural queen cell base, and all cups should be identical. Grafting is harder in a cup that is too narrow; in one that is too wide, the bees use extra wax to narrow the mouth.
• Inner surface: Smooth, without burrs; no mould marks or sharp edges at the bottom.
• Fitting: The strip should sit tightly on the bar but be removable by hand. A strip that slips during transport puts the whole batch at risk.
• Durability: It should be slightly flexible, keep its shape when washed in hot water and not crack easily.
• Compatibility: The strip length must match the inner width of your collection frame and the bar type.

How do you prepare a new strip for use?

1. Wash: Wash in lukewarm water and, if necessary, an unscented cleaner; rinse thoroughly and dry.
2. Let the bees clean it: Fit the strips to the frame and give them to a strong colony for about a day before grafting. The bees clean the cups, coat the inner surface with a thin layer of wax and remove the smell. This is called having the cups polished.
3. Optional priming: Some producers put a tiny amount of clean melted wax, or a drop of royal jelly diluted with water, into the bottom of the cup. For beginners, letting the bees clean the cups is enough.
4. Keep cool: Polished strips are protected from dust and sun until grafting.

Royal jelly production with plastic strips, step by step

1. Grafting: The youngest possible larvae (less than a day old) are placed at the bottom of the cups with a grafting tool. It helps to work with the strip facing up on an inverted bar.
2. Giving it to the colony: The bar is turned back and the frame is placed without delay in the middle of the production colony, where nurse bees are densest.
3. Waiting: About 72 hours after grafting, the jelly in the cup is at its peak.
4. Harvest: The strip is taken to a cool, bee-proof room. The wax extension added by the bees is cut off with a sharp knife, the larvae are removed with tweezers and the jelly is collected with a spoon or by vacuum.
5. Regrafting: Many producers do not scrape the cup out completely; they leave a very thin layer of jelly at the bottom and regraft the same day. This delays drying of the new larva.

Cleaning and storing plastic strips

The cleaner the strip, the higher the acceptance. After each harvest, the wax, jelly and larval remains left in the cups spoil and give off a smell.

• Quick reuse: Strips to be regrafted the same day are only cleared of the wax extension and remains; there is no need to wait for them to dry.
• Full cleaning: When production pauses, strips are pre-rinsed in cold water and then washed in lukewarm water. Water that is too hot can deform the plastic and the wax.
• Chemicals: Scented detergent, bleach or degreaser are not used; if they are, rinse so that no residue remains.
• Storage: Completely dry strips are stored in a closed, dust-free box, away from strong-smelling substances such as varroa treatments and fuel.
• Sorting: Strips that are cracked, deformed or have a roughened inner surface are taken out of production.

Common mistakes

• Grafting a new strip straight away: Factory odour and surface residue markedly reduce acceptance.
• Giving more strips than the colony can handle: More cups than the colony can feed means less jelly per cup.
• Piercing the larva at harvest: Larval fluid mixes into the jelly and clouds the product.
• Grafting into a dried-out cup: In a cup left standing for a long time after harvest, the larva dries out quickly.
• Storing strips alongside chemicals: The plastic absorbs the smell.