Developments in probiotics

Back to Functional Food index

The popularity of probiotic products shows no sign of waning. A new capsule technology enables the delivery of living cell cultures direct to the intestine, without requiring damaging production methods.

Morinaga Nutritional Foods Deutschland GmbH

Products using probiotics, such as yoghurt, have significantly increased in the food market recently. Also, the use of Bifidobacterium or Lactobacillus in capsules and tablets has become popular in the probiotic supplement market.

Probiotic products contain living cells, so care must be taken to ensure product stability during shelf life in order that the cell count can be maintained. It is important to note that supplement products have a long shelf life – of more than one year – so manufacturers must take this into consideration when producing probiotics products. In order to produce probiotic products with good stability, it is very important to keep water activity low and not to expose products to risks, such as heat shock, that will cause a loss in probiotic activity during the production process.

At the same time, in probiotic supplements, attention is often paid to the tolerance rate to stomach acid. Enteric capsules coated with chemical materials have been developed to protect capsules from gastric juices.

However, in the production process of enteric coated capsules, water or other solvents, such as alcohol, are usually used. Also, heat shock is applied during the drying process. These factors create a problem with the stability of live probiotic cells and contribute to a decreased viable cell count. Further, if too much chemical coating material is applied to capsules or tablets, they may not properly dissolve in the intestine. So, manufacturers must employ skilled workers able to carefully control the coating process and, above all, to avoid over-coating.

When the capsule was put into low pH solution (pH 2.5) in an L-tube and shaken gently at 37˚C, the powder in the capsule solidified into a shape similar to that of the original capsule after dissolving the gelatin capsule. Even if the solidified powder was shaken continuously in the same solution for 60, 120 and 240 minutes, the solidified powder was not disrupted (see Figure 2). Similar results were observed at pH 1.5 and 3.5 solutions.

This result indicates that, following ingestion, the capsule manufactured by using Probiotic GFR technology can go through the stomach without disruption.

On the other hand, when placed into neutral solution (pH 6.5) and shaken gently at 37˚C, the capsule starts to disrupt very smoothly as shown in Figure 3. After 30 minutes, the major part of capsule is disrupted, and the entire capsule is nearly dissolved after 60 minutes. Similar results are observed in the case of pH 6.0 and pH 7.0 solutions. Also, when the solidified powder formed in low pH solution was put into neutral pH solution, the solidified powder soon dissolved.

These results indicate that the capsule using Probiotics GFR technology can pass through the human stomach then, dissolve in the intestine where the living probiotic cells are released.

Further benefits

The probiotic GFR capsule has lower water activity than the enteric coated capsule because no water is used during processing. Due to lower water activity, stability of probiotic cells in GFR capsules is expected to be much better than in enteric coated capsules. In the case of using gelatin capsules (Figure 1), water activity is about 0.15. If cellulose capsules are used, the water activity will be reduced to less than 0.1, so better stability can be expected.

In addition, some conditions which can cause damage to living cells, such as adding water, alcohol, or heating during the drying process, are not necessary during the manufacturing of Probiotic GFR capsules because the process is merely filling Probiotics GFR powder into conventional hard capsules. So, living cell counts do not change during the manufacturing process.

As special techniques are not necessary, nearly all manufacturers that are producing vitamin capsules can produce the probiotics GFR capsules without technical difficulty.

• Water activity can be kept lower so that good stability of probiotic cells can be expected.
• Neither water nor other solvents, such as alcohol, are used. Heat for drying is not necessary for the producing Probiotics GFR capsules. Therefore probiotic cells are not damaged during processing.
• Neither special tools, such as a coating-pan or granulator, nor skilled techniques are necessary.
• Artificial ingredients are not used.
• Almost all manufacturers producing vitamin capsules can produce stable Probiotic GFR capsules without special techniques.

This unique probiotic capsule technology will help many supplement manufacturers produce gastric fluid resistant probiotic capsules with good stability.