Deteriorating Lac Glaze – Dull Panned Products

By Reg Groves

Question: We produce chocolate-coated nuts using revolving pans and a lac glaze. Initially the finish is brilliant and shiny, but in a few weeks, the finish deteriorates. Why?

Answer: This manufacturer succeeded in applying a smooth coating of chocolate, which was then glazed without the intermediate step of polishing. To do so requires a larger application of glaze than would be the case if the candies were polished. For normal glazing, about five ounces of lac glaze per 100 pounds of product would be applied. In this case, 12 ounces were used.

At first, when the glazing pans were clean, this procedure worked reasonably well. But after an excessive quantity of glaze is used, the pan becomes heavily coated with glaze. This was found to be the case, and the thick coat of glaze was very rough.

Whenever a fresh batch was glazed, using the excessive quantity of lac glaze, the pan would receive such a heavy coating, that the thick build-up would become softened by the solvent in the next application. As the pan was occasionally turned to loosen the candies during the glaze drying stage, they would stick to the pan, and to one another. As a result, the glazed surface was spoiled.

The first step to solving the problem was to clean the heavy coating from the glazing pans. This was not easy because the glaze is only soluble in alcohol. Washing with hot detergent water and hard work with a brush were needed to clean down to the metal.

The procedure was then changed to incorporate polishing before glazing. A solution of one part regular corn syrup to one part water was used for polishing. First application: four ounces; second application: four ounces to 100 pounds of product; third application: two ounces.

Between each application, the pan was run with a little air, to assist drying. After the third application and drying, a good polish developed. The polishing stage was followed by glazing, but only five ounces of glaze were applied to 100 pounds of product. The glaze spreads more easily on polished surfaces, and a thin coat can be applied, with little transfer to the surface of the pan.

The glaze was then dried with the pan not in motion, and with full volume of cooling air. By occasionally turning the pan one-half revolution while drying, sticking together is prevented. But the pan must not run continuously while drying the glaze, or the surface will be spoiled.

It is not necessary to wash glazing pans frequently. But as a coating of glaze gradually develops, it can be removed with hot water, detergent and scrubbing. Most companies make their own polishing solutions, using various combinations of corn syrup, sugar, gum arabic or other gums. There are prepared polishing solutions available commercially. One in particular is very effective in re-polishing the surface of spoiled batches. Lac glaze is usually purchased, already prepared in an alcohol solvent. END

 
(How to control soft panning, continued)

Dependent upon the care in measuring quantities of syrup and sugar, and the allowance of sufficient time for compaction, finished batches may have higher or lower ratios of syrup to dry sugar in the coating.

Too much sugar and too little compaction time will result in batches that have a loose jacket structure, with too much syrup between each sugar particle. These may crack at the polishing stage and may become sticky in storage.

Too little syrup and too long a compaction time will grind too much of the crystalline sugar to dust and squeeze the sugar crystals too closely together. The result will be brittle, dry-eating product.

Since soft panned products are finished at the engrossing stage, with a final coat of powdered sugar, they look the same whether too moist or too dry. So, the panner may feel that all of the product is good.

In most soft panning operations, syrup and sugar are drawn from large containers, common to several pans. The quantities of syrup and sugar for each application are judged by “dippers” and “scoops.” This is not close enough control for consistent product.

By studying several batches, for which the quantities of syrup and sugar for each application are weighed, a standard “recipe” can be constructed. In addition, the optimum interval between doses can be determined, and a standard time schedule written.

From this study, the total quantity of syrup, fine crystalline sugar and powdered sugar can be determined and pre-weighed for each batch.

It may not be practical to weigh every dipper and scoop, but total batch quantities will provide guidance to the panner, knowing that he or she has to divide them between a specified number of applications over a specified time schedule.

This approach to controlling the process and eliminating variables can be a valuable tool for management and panners alike. END
 

 

 

(Shiny panned candies continued)

Sugar-coated products are usually polished with carnauba, a vegetable wax powder or paste. The polishing pan may be lined with melted wax, or powdered wax may be sprinkled onto the tumbling product. In either case, very little wax is picked up on the surfaces, but after about 30 minutes of fairly fast tumbling in cool conditions, a good shine develops.

In the soft-panning process, such as for jelly beans, the sugar coating is built up by alternate layers of syrup and fine-granulated sugar. In this case, the syrup acts as an adhesive. When the sugar is added, it adheres to the sticky surfaces. The combined effects of rubbing and pressure compact the sugar to form a smooth coating. The last two or three coats should be with powdered sugar.

However, a still smoother surface is needed to take a good polish. As a second phase, apply two or three “wettings” of sugar syrup, at about 65 percent solids, to finish with a coat of very fine sugar crystals. Thereafter, polishing procedures are similar to those described for hard-shell products.

Chocolate panned goods
With chocolate panned goods, the coating sets by cooling. If cooling is too rapid, then an “orange peel” effect is produced, which is difficult to polish or glaze. The proper technique is to control the temperature in the pan, so that the coating is soft enough to rub smooth by abrasion and pressure. Thereafter, the coated goods are well cooled because a soft surface will not polish well.

Chocolate-coated products are polished usually with a solution of sugar and/or corn syrup or proprietary polishing solution. Two or three light applications are allowed to run until dry, which develop into a good shine and a skin. Thereafter, a thin coat of edible lacquer is applied in a revolving pan and allowed to dry without tumbling.

There are many more facets to finishing panning processes, in addition to smoothing. END

 



 
Biography:
Reg Groves has garnered many honors throughout his distinguished career including induction into the Candy Hall of Fame, Class of 2010. His complete biography is posted at Link.
 

 

 


Confectionery Classics 

Soft Panning Colors

By Reg Groves

Editor’s Note: The question-and-answer format evolved as readers submitted processing problems to the publication. Anonymity is always protected.

Question: We manufacture soft-panned products such as jelly beans and bird eggs. It is noticeable that the light colors are more firm and dry than dark colors. The dark ones are difficult to polish and become sticky, more so than the lighter shades. Can you offer an explanation for this problem?

Answer: The solution to this problem required careful study of the process. An initial investigation appeared to indicate that the conditions were consistent from color to color. Syrup was prepared in large batches, with the ingredients carefully weighed, and the solids content consistently controlled by refractometer. A bulk batch of syrup would be divided into several portions, in weighed quantities, for coloring and flavoring.

A study of the panning process revealed no significant variables. Although soft panning requires experience and judgment for success, the pan personnel were skilled, and each one, over a period of time, would produce the whole range of colors. So the problem was not related to excessive applications of coating syrup by one or more of the employees.

The subsequent stages of drying, smoothing, and polishing were consistently controlled.

Further investigation revealed the cause of softness and stickiness. The colors in use were all liquids made up to standard concentrations from dyes, at the plant. But white required no liquid color, and yellow required very little, whereas mauve, red, and black needed heavy dosages of color, to produce the desired shades.

Although the coating syrup was initially prepared to a standard concentration, it then became significantly diluted, dependant upon which color was added to it. So the coating syrups for dark colors contained more water than those for light syrups, and thus dark products tended to be soft and sticky.

The remedy was to adjust the solids content of the base syrup, to compensate for the water added with the color. This rather complicated the syrup preparation, but was a necessary step to cure the inconsistent quality.

An alternative could have been to use water-soluble paste or jellied colors, and so eliminate the water added with liquid colors. END
 
 
     



 
How to Control Soft Panning

By Reg Groves

Sugar coating in revolving pans has long been regarded as a mysterious art, and “panners” as having skill akin to sorcery.

No doubt, in the absence of real process control, the panner demonstrates considerable skill. Much of this skill is in knowing how to deal with variables associated with centers, ingredients and atmospheric conditions.

But, the real skill is in judging the correct applications of sugar and syrup, and the intervals between them.

Let me elaborate upon this latter point. Many sugar panning and chocolate panning operations are closely controlled, or automated, as to the dosages of coating material. This is fairly simple, using sprays or drip feeds, with a single coating fluid and automatic timers.

But soft panning requires alternating applications of an adhesive syrup and dry sugar. The measurement of dosages is almost invariably a judgment call by the panner, but personal visual judgment can lead to significant variations in the end product.

These variations may never be seen by the panner, or communicated to the panner as a quality variable having its source at the engrossing stage.

Such variations can be very serious, taking the forms of product that stick together in storage, or of dry, brittle, sugar jackets.

Assuming that all other upstream variables have been eliminated, it is still possible to apply different ratios of syrup to dry sugar from one batch to another, or from one panner to another.

The process is one of applying a thin coat of adhesive syrup, and then compacting into that syrup as much crystalline sugar as can adhere to it.

This does not occur immediately, but each application of syrup requires enough sugar, and sufficient time, for rolling and compaction. The effect of compaction and arrangement of sugar crystals by rolling and pressure is to squeeze excess syrup to the surface.

(continued on next column)







Production of shiny, panned candies

by Reg Groves

In the production of revolving pan-coated candies, there seem to be more problems raised in polishing and glazing than in any other stage.

In general, sugar-coated products are polished with wax. Also in general, chocolate-coated products are glazed with an edible lacquer. The procedures and process requirements for success are quite different from one another.

But there is one common factor. Unless the surfaces to be polished or glazed are really smooth and fine-textured, then it is impossible to produce a good gloss.

An analogy is in trying to work up a good polished surface on an old, weather-beaten car. No matter how much polish is applied the surface never really shines because the base coat is rough.

Let us consider hard sugar-coating first, such as sugared almonds. The sugar coat is applied by many “wettings” of sugar syrup, each of which is caused to dry on the surfaces of the almonds while they tumble in the pan. Each wetting contributes a very thin coat of sugar crystals.

If the process is rushed by using coating syrup that is too concentrated or by force-drying then the sugar shell will be composed of rather large crystals. Such a shell will be difficult to polish.

The process may be started with syrup of about 75 percent solids, but toward the end of the coating and coloring stages, the solids should be gradually reduced to 60 to 65 percent. By so doing, rough surfaces tend to become smoothed by filling between the large crystals with small crystals. If the final syrup applications are allowed to dry slowly, fine crystals will be formed.

An “old-timers” method of judging smoothness is to take candy from the pan and lick the surface. The tongue can readily detect roughness. But please don’t throw the sample back in the pan.

It is important that once the final smoothing coat has been applied and dried, the product should not be allowed to continue tumbling in the pan. This will cause dusting by abrasion. Dusty product does not polish well.

For this reason, polishing pans should be located in a separate room, away from dusty coating operations.

(continued on next column)
Publisher's Note:
The article above is published from correspondence by Reg Groves, President, Groves & Company, that was originally printed in Candy Industry magazine as the "Candy Doctor," for Knechtel, and “Confectionery Workshop” columns. Permission from Knechtel, and Candy Industry, has been granted to Pat Magee, P Magee Enterprises.

As each new column is posted, previous formulations will be archived by subject and available for purchase at a nominal cost. 
For more information please contact plmagee@earthlink.net.