Ice Cream Flavours

Introduction

Most ice cream is purchased by the consumer on basis of flavour and ingredients. There are many different flavours of ice cream manufactured, and to some extent limited only by imagination. Vanilla accounts for 30% of the ice cream consumed. This is partly because it is used in so many products, like milkshakes, sundaes, banana splits, in addition to being consumed with pies, desserts, etc.

It is the ice cream manufacturers responsibility to prepare an excellent mix, but often they put the responsibility of the flavours and ingredients on the supplier.

US Ice Cream Consumption by Flavour, 2010
                                          percentage of volume

1.     Vanilla                                 28.8
2.     Chocolate                            14.3
3.     Bakery/cake/cookie             13.6  
4.     Chocolate chip / other choc   8.6 
5.     All nut flavors                        4.7
6.     Strawberry                             3.3
7.     Neopolitan                             2.5
8.     Coffee                                    1.6
11.   All other flavors                   22.6

Source:  Dairy Facts, 2011, International Dairy Foods Association

Ingredients are added to ice cream in four ways during the manufacturing process:

  1. Mix Tank: for liquid flavours, colours, fruit purees, flavored syrup bases Ð anything that will be homogeneously distributed in the frozen ice cream.
  2. Variegating Pump: for ribbons, swirls, ripples, revels
  3. Ingredient Feeder: for particulates - fruits, nuts, candy pieces, cookies, etc., some complex flavours may utilize 2 feeders
  4. Shaker table: for large inclusions

Generally, the delicate, mild flavours are easily blended and tend not to become objectionable at high concentrations, while harsh flavours are usually objectionable even in low concentrations. Therefore, delicate flavours are preferable to harsh flavours, but in any case a flavour should only be intense enough to be easily recognized. Flavouring materials may be:

  1. Natural
  2. Artificial or imitation
  3. Blends of the two

Vanilla

Vanilla is without exception the most popular flavour for Ice Cream in North America. The dairy industry uses half of the total imported vanilla to North America. It is a very important ice cream ingredient, not only in vanilla ice cream, but in many other flavours where it is used as a flavour enhancer, e.g. chocolate much improved by presence of vanilla.

Vanilla comes from a plant belonging to the orchid family called Vanilla planifolia. There are several varieties of vanilla beans among which are Bourbon, Tahitian, Mexican. Bourbon beans are used to produce best vanilla extracts. Bourbons from Madagescar are the finest and account for over 60% of World production, Indonesia, 23% (UN FAO 2005).

From each blossom of the vine that is successfully fertilized comes a pod which reaches 6-10 inches in length, picked at 6-9 months. It requires 26-29oC day and night throughout the season, and frequent rains with dry season near end for development of flavour.

Pods are immersed in hot water to "kill them" (also increases enzyme activity), then fermented for 3-6 months by repeated wrapping in straw to "sweat" and then uncovered to sun dry. 5-6 kg green pods produce 1 kg. cured pods. Beans then aged 1-2 yrs. Enzymatic reactions produce many compounds - vanillin is the principal flavour compound. However, there is no free vanillin in the beans when they are harvested, it develops gradually during the curing period from glucosides, which break down during the fermentation and "sweating" of the beans. Extraction takes place as the beans are chopped (not ground) and placed in stainless steel percolator and warm alcohol (50oC, 50% solution) is pumped over and through the beans until all flavouring matter is extracted.

Concentrated Extract

Vacuum distillation takes place for a large part of the solvent. The desired concentration is specified as two fold, four fold, etc. Each multiple must be derived from an original 13.35 oz. beans.
Vanilla can be and is produced synthetically to a large extent. By-product of pulp and paper industry (lignan) or petrochemical industry (guaiacol). Compound flavours are produced from combination of vanilla extract and vanillin. Vanillin maybe added at one ounce to the fold and labelled Vanilla-Vanillin Flavour. Number of folds plus number oz. of vanillin equal total strength, eg. 2 fold + 2 oz. = 4 fold vanilla-vanillin. However,more than 1 oz to the fold is deemed imitation.

Vanilla flavouring is available in liquid form as:

  • Natural Vanilla
  • Natural and artificial (reinforced Vanilla with Vanillin)
  • Artificial Vanilla (vanillin)

Usage level in the mix is a function of purity and concentration, usually ~0.3%.

Some vanillin actually improves flavour over pure vanilla extract but too much vanillin results in harsh flavours. 

The choicest of ice creams can be made only with the best of flavouring materials. A good vanilla enhances the flavour of good dairy products in ice cream. It does not mask it.

Chocolate and Cocoa

The cacao bean is the fruit of the tree Theobroma cacao, (Cacao, food of the gods) which grows in tropical regions such as Mexico, Central America, South America, West Indies, African West Coast. The word cocoa is a corruption of the native word cacao. The beans are embedded in pods on the tree, 20-30 beans per pod. When ripe, the pods are cut from the trees, and after drying, the beans are removed from the pods and allowed to ferment, 10 days (microbiological and enzymatic fermentation). Beans then are washed, dried, sorted, graded and shipped.

At the processing plant, beans are roasted, seed coat removed - called the nib. The nib is ground, friction melts the fat and the nibs flow from the grinding as a liquid, known as chocolate liquor.

Liquor:

55% fat, 17% carbohydrate, 11% protein, 6% tannins and many other compounds (bitter chocolate - baking).

Cocoa butter:

fat removed from chocolate liquor, narrow melting range 30 to 36° C

Cocoa:

after the cocoa butter is pressed from the chocolate liquor, the remaining press cake is now material for cocoa manufacture

The amount of fat remaining determines the cocoa grade:

  • medium fat (Breakfast) cocoa 20-24% fat
  • low fat 10-12% fat

Flowchart of how cocoa powder, plain or milk chocolate, and chocolate coated products are made

Cocoa powder can also be alkalized, which reduces acidity/astringency and darkens the colour. Slightly alkalized cocoa is usually preferred in ice cream because it gives a deeper colour but the choice depends upon:

  • consumer preference
  • desired color (Blackshire cocoa may be used to darken color)
  • strength of flavour
  • fat content

There are many types of chocolate that differ in the amounts of chocolate liquor, cocoa butter, sugar, milk, other ingredients, and vanilla.

Imitation chocolate

replacing some or all of the cocoa fat with other vegetable fats. Improved coating properties, resistance to melting

White chocolate

cocoa butter, MSNF, sugar, no cocoa or liquor

In chocolate ice cream manufacture, cocoa is more concentrated for flavouring than chocolate liquor (55% fat) because cocoa butter has relatively low flavour. However, the cocoa fat adds texture to the ice cream. Acceptable mixes can be made using 3% cocoa powder, 2.5% cocoa powder plus 1.5% chocolate liquor, or 5% chocolate liquor.

A good chocolate ice cream will be made if the cocoa and/or chocolate liquor is added to the vat and homogenized with the rest of the mix. Chocolate mixes have a tendency to become excessively viscous sostabilizer content and homogenizing pressure need to be adjusted.

One problem is called chocolate specking. It can occur in soft serve ice cream, when cocoa fibres become entrapped in the churned fat.

Fruit Ice Cream

Fruit for Ice Cream is available in the following forms:

  1. Fresh Fruit
  2. Raw Frozen Fruit
  3. Open Kettle Processed Fruit
  4. Aseptically Processed Fruit

Advantages of processed fruits:

  1. Purchasing year round supply: problems of procurement and storage transferred to fruit processor
  2. Availability: blending of sources from around the world in RTU form, no thawing, straining, etc.
  3. Quality control: processor adjusts for quality variations
  4. Ice Cream quality: fruit won't freeze in ice cream, usually free of debris, straw, pits.
  5. Microbial Safety
  6. Convenience

Fruit feeders are used with continuous freezers to add the fruit pieces, while any fruit juice is added directly to the mix. Fruit is usually added at about 15-25% by weight.

Nuts in Ice Cream

Nuts are usually added at about 10% by wt. Commonly used are walnuts, pecans, filberts, almonds and pistachios. Brazil nuts and cashews have been tried without much success.

Quality Control of Nutmeats for Ice Cream

  1. Extraneous and Foreign Material: Requires extensive cleaning, Colour Sorter, Destoner, X-rays, Aerator, Hand-Picking, Screening
  2. Microbiological Testing: Aflatoxin contamination can be a hazard with Peanuts, Pistachios, Brazils. All nutmeats should receive random testing for: Standard Plate Count, Coliform, E. Coli, Yeast and Mold, Salmonella.
  3. Bacteria Control: Nuts must be processed in a clean sanitary premise following good manufacturing practices. Nuts should be either oil roasted or heat treated to reduce any bacteria.
  4. Sizing: Some nutmeats require chopping to achieve a uniform size in order to fit through the fruit feeder, i.e.: Pecans, Almonds, Peanuts, Filberts
  5. Storage Nutmeats should be stored at 34-38° F to maintain freshness and reduce problems with rancidity.

Colour in Ice Cream

Ice cream should have a delicate, attractive colour that suggests or is closely associated with its flavour. Almost all ice creams are slightly coloured to give them the shade of the natural product 15% fruit produces only a slight effect on colour. However, most suppliers, would include some colour in the fruit to save the processor time i.e. solid pack strawberries include colour. Most colours are of synthetic origin, must be approved, purchased in liquid or dry form. Solutions can easily become contaminated and therefore must be fresh.

Colours are used in ice cream to create appeal. If used to excess they indicate cheapness. The choice of shade is dictated by flavour, i.e. red for strawberry, light green for mint, purple for grape, etc.