Processing Techniques Ensure Product Consistency

Processing Techniques Ensure Product Consistency

by Heather Granato

A consumer stops at a high-end bakery on his way home fromwork and picks up a few chocolate chip cookies as a treat for the family. Thenafter dinner, his disappointed son discovers his cookie has no chips, while hisdaughters cookie is packed with chips. Perhaps they can split the cookies, ensuring fair chipdistribution. Obvious problem, obvious solutionbut a likely lost customer forthe bakery.

What if this problem occurred with the familysmultivitamins? Not such an obvious problem, as nutrient deficiencies and highdosages arent necessarily immediately visible. However, it is a problem ifthe children receive toxic doses of iron from their multi or dad received nocoenzyme Q10 (CoQ10) to offset deficiencies caused by his blood pressuremedication. These are quality control problems that can compromise consumerhealth.

Avoiding this problem in nutrient delivery means carefulcontrol of the blending and processing steps in production. Without properblending, the best conceived product may be a failure in terms of ingredientquality claims, taste and dispersion, said Eric Barber, national salesmanager with Lawrenceville, Ga.-based Valentine Enterprises. Proper know-howmust be applied to each specific product, which should be tested for uniformityof content on an ongoing basis.

Doug Gillespie, president of Pro-Form Laboratories in Orinda,Calif., agreed with this assessment. Blending is a critical step to theefficacy of a finished product, he said. It takes an experienced batch maker to be able to make theproper adjustments and turn out the same product day after day.

There is a range of techniques available to processors toensure the final capsules, tablets or packets are homogenous, highqualityproducts. Every ingredient has to be in every part of the blend in order forthe final product to contain what it is supposed to have, said John Blanco,sales and marketing director for AnMar International in Bridgeport, Conn. Thebottom line is to know what factors will deteriorate your materials and shortenshelf life, and avoid that result.

Making a high-quality finished product starts with ingredientselection, and continues through processing and delivery form before reachingthe consumer. Each part of the process is designed to combine the ingredientsinto forms that will not adversely interact, but instead deliver qualitynutrition to a consumer. Think about this process as a modular approach,said Ram Chaudhari, Ph.D., senior executive vice president at Schenectady,N.Y.-based Fortitech. You start with a group of ingredients and combine themto become less reactive and make two or three modules. Then you combine those for a finished product that meets thehomogenicity test.

While every ingredient has its own dossier of physicalproperties and potential interactions, primary considerations include particlesize, moisture content, ingredient percentages and bulk density. Each must beaddressed individually before the formula makes it into the blender.

Matching particle sizes of different ingredients ensuresconsistent distribution in a blend and contributes to stabilizing densities andmoisture content. It is unusual for all the ingredients in a blend to be thesame size. However, manufacturers can also work with their suppliers to attemptto ensure consistent particle size among ingredients. We stipulate and testfor correct mesh size from our suppliers to ensure ingredient uniformity,said Dave Sandoval, president of Long Beach, Calif.- based Organic by Nature.This lowers the impaction rate and need for processing.

In many cases, though, the materials undergo some type ofprocessing to ensure size conformity and adhesion quality. Two primaryprocessing techniques that affect particle size are milling and granulation.

Milling (grinding) is a fairly straightforward procedure,often used with botanical ingredients to break down larger particles into aspecific smaller size. Material passes through cutting chambers and is forcedthrough mesh or perforated screens, resizing larger materials to a smaller setstandard.

On the other end, granulation increases particle size bycombining ingredients. Wet stage granulation (or agglomeration) uses a fluid(water or alcohol) to stick the powder ingredients together, forming larger,more porous combinations. The solution is then heated to dry out the particles,which remain in their new matrix. Dry granulation uses mechanical force tocompact the ingredients. Granules tend to flow better, are less dusty and dissolve morequickly than a combination of fine powders. The best agglomerate adds nothing new to the product and retains theoriginal moisture range, as well as improves the dispersion, uniformity anddensity of the finished product, Barber said. Granulation can be used priorto blending, or after blending, depending on the formula needs and the desireddelivery form.

Wet granulation obviously affects moisture content, which isitself a processing consideration. This issue encompasses the moisture contentof individual materials and their hydroscopicitywater affinity. In workingwith whole food ingredients, such as botanicals, moisture levels can varydepending on the time of year, growing conditions, harvesting techniques andstorage situation. Therefore, working with contract manufacturers that haveexperience in working with such ingredients can take the guesswork out of how tomeasure and account for variations in moisture content.

An ingredients propensity for absorbing moisture from otheringredients must also be accounted for in evaluating moisture issues. Coenzyme Q10 (CoQ10) is an example of a hydroscopic particleoften used in small quantities in formulas, Sandoval said. If you just add asmall amount into a formula, it would likely clump with other ingredients andnot disperse, he said. Instead, you dilute it into another ingredientusing a small quantity Kelsinator or dispersion blender. This dispersionensures the CoQ10 does not take on additional moisture during blending, thusforming clumps that could affect the finished flow.

Dispersion is commonly used not only for ingredients with highmoisture content, but also for those added in microgram quantities to a formula.If an active ingredient is very small compared to the total weight, stepsmust be taken to ensure the active will be found in each dosage at an acceptablelevel, said Gary Callahan, vice president of technical and regulatoryaffairs for City of Industry, Calif.-based Best Formulas. To ensure a minutequantity of a vitamin, for example, is spread throughout a large blending run,the ingredient is dissolved into formula and then agglomerated to add to thetotal mix. This solubilized combination formula is then a single module in theassembly of the formula moving forward.

Such modules are combined with individual nutrients, and everyportion of the mix has a different weight and density. Formulators must considerthe natural propensity of ingredients to stratify in solution. The goal ofblending is to combine the ingredients so they have uniform dispersion, withoutoverblending, where ingredients begin to settle out. It is critical to payattention to blending sequence and blending times, Gillespie said. Densitiesare always a battle. Also, if you under blend or over blend, you can have aproduct that does not have a homogenous mix. You may have hot spots thatcontain too much of an ingredient or cold spots that do not containenough.

The type of materials and final delivery form influences thetype of blender. In the nutraceutical industry, there is a range of options. Vblenders are possibly the most common, in which materials are tumbled togetherand separated into the V arms, often using a intensifier bar to further break upthe material. Other options include cone blenders, drum blenders and ribbonblenders. Several contract manufacturers noted they have their blenders customdesigned and built to meet in-house specifications and SOPs (standard operatingprocedures).

A well-rounded company must have several types of blendingand processing equipment, Callahan said. Most common would be a tumbletype blender, a ribbon type blender and a high shear type blender. Additional equipment such as sifters, grinders and granulatorsmust also be available to allow for various types of processing to achieve thedesired specification of the blended product.

Ultimately, blending is a vital step in the productionprocess. Attention to detail ensures quality materials ultimately deliver whatis promised to the consumer. There is no simple answer, Chaudhari said,and no substitute for experience to learn the tricks of the trade.