DD227039A1 - METHOD FOR PRODUCING A DRY FRUIT PRODUCT - Google Patents

Abstract

The invention relates to a method for producing a dried fruit product. The products can be used in the confectionery, food, bakery and long-life bakery industries as well as in the household. It is the object of the invention to produce dry fruit-like products from readily available raw materials with low technical-technological, time and energy expenditure. The essence of the invention is that fruit and / or vegetable products at a temperature of 15 ... 30C with an osmotic solution, which has an invert sugar content of 75 ... 85%, treated, the osmosis, circulated, the products are continuously purged and pumped off after 20-24 h and the resulting dry fruit-like products with a dry matter content of 60-75% are processed either directly or after drying to a final moisture content of 25% of the further processing.

Description

a) Title of the invention

Process for producing a dried fruit product

b) Field of application of the invention

The invention includes a process for the production of dried fruits by predominantly osmotic drying. These dried fruits, preferably from cherries and plums but also e.g. made from apple, pear, gooseberry or pumpkin, are suitable for use in the confectionery, food, bakery and long-life bakery industry as well as in the household.

c) Characteristic of the known technical solutions

In the baking and confectionery industry, fruit is not only used as fresh fruit, but often in preserved form.

In this case, play such properties as long shelf life, easy storage, easy handling during processing, baking stability and pleasant, for example, the pastry flavor positively influencing taste, a major role.

Commonly used methods of fruit preservation are drying and candying. While for drying only a few fruit species not available everywhere, e.g. Grapes for the production of raisins or sultanas are suitable for candying for the production of Dick Zucker fruits various, readily available fruits and vegetables.

When candying while Hensel and cousin (raw materials for baked goods in overviews, VEB Fachbuchverlag Leipzig, edition 1981) is so proceeded that the fruits or vegetables after such pretreatments such. Watering, stoning, stalking, peeling etc. are gradually treated with increasingly concentrated sugar solutions of white sugar, water and corn syrup (18%) with short-term exposure to heat (up to 100 ° C) or with constant exposure to heat If the fruits remain in the sugar solution, then the fruits of the crop are preserved in thick sugar solution.

If the fruit is covered with a thin icing after the sugar solution has run out, it is called glazed fruit. By treatment with supersaturated sugar solution it is still possible to produce crystallized crops.

The physical process of osmotic drying is the basis for making thick sugar crops. The drying is based on the migration of water through a semipermeable wall at osmotic pressure differences. It comes to a sugar accumulation in the fruit or to the water outlet from the fruit.

In DE-AS 1692206 the conventional Kandierung is described in detail and reference is made to the deficiencies. Thus, the prepared and optionally with a dilute solution of sulfurous acid or sulfur dioxide pretreated and / or boiled fruits for 24 hours in a syrup containing about 25 wt .-% sucrose and / or glucose. The syrup is then allowed to drop off and brought to a concentration of about 30% by weight by addition of sucrose and / or glucose. With this, the fruits are again brought into contact for another 24 h. This process is repeated with an increase in the sugar concentration by 5 wt .-% / day until the syrup one

Concentration of about 80% has reached. In this Kandierverfahren the sugar concentration of the syrup must be slowly increased because the fruits shrink at rapid increase.

The known method is liable as. it can be seen from the above, the lack of that they are very time consuming (5 to 21 days per batch). To shorten the Kandierzeit according to DE-AS 1692206, the treatment of the fruits to be candied with an enzyme mixture which is formed by Aspergillus niger, at the latest at the beginning of the Kandierverfahrens proposed. The time for candying is reduced to about 5 days.

German Offenlegungsschrift No. 3230025 describes a process for infusing fruits in which an appropriate osmotic shock, caused by the fruit being mixed with sugar solutions to a high concentration, is avoided by suitable process management and the reduction of the fruit volume is kept to a minimum Fruits are infused by immersing them in two or more baths containing dissolved sugars whose concentration gradually increases, so that the solids content of the fruit gradually increases to about 32 to 35% by weight.

The infusion process can be carried out batchwise or continuously. In a continuous mode of operation, the water-content reduction solutions separated from the infused fruits at each stage of the process may be passed through an evaporator so that they are restored to their original sugar solids content. By adding sugar, more concentrated solutions for further infusion are finally produced. The Dickzuckerfrüchte produced by the various Kandierverfahren are mainly for garnishing and z.T. used as fruit fillings in baked goods. However, they do not give the final product the fruity-aromatic note, as is known, for example, from raisins, but leave only a sweet or one-sided aroma.

sensation of taste, since the constituent composition, especially carbohydrates and fruit acids, is strongly influenced by e.g. Raisins deviates. Furthermore, according to (Brot und Backwaren, Hamburg 32 (1984) 5, p. 122-123) there is the danger that if the amount of sucrose in the osmotic solution is too high, the sugar will crystallize as a result of atmospheric moisture evaporation and hard spots will form in the fruit.

However, the main deficiency of the known candying methods consists in the long candying period (at least 5 to a maximum of 21 days) and in the fact that the candied fruits do not meet the requirements for baked fruits.

d) Object of the invention

It is the object of the invention to produce dry fruit-like products from readily available raw materials with little technical-technological, time and energy expenditure.

e) Presentation of the essence of the invention

The invention has for its object to identify process conditions that make it possible to produce dry fruit-like products from readily available raw materials. It has been found that by treating fruit and / or vegetable products with a highly concentrated sugar solution containing 75 ... 85% invert sugar, dry fruit-like products develop within 20 ... 24 h, whose appearance, ingredient composition and sensory properties are more natural Are similar to dried fruits. The fresh or intermediately stored, eg with SO ₂ preserved, whole or cut into pieces fruit and / or vegetable parts, preferably of plum, cherry or pumpkin, are flowed through by osmotic solution of constant concentration according to the invention. The fruit or vegetable parts are on sieve inserts. The pumped osmosis

solution is returned to the circuit after adjustment to the starting level of invert sugar. The concentrated sugar solution is previously inverted by means of tartaric or citric acid.

After candying for 20 to 24 hours, the osmotic solution is pumped off, and the resulting dry fruit-like products with a dry matter content of 60 to 75% are either directly or after drying to a final moisture content of

6. 25% of further processing. The products with a final moisture content of 25 % are produced by drying for 50-60 minutes at room temperature and subsequent drying at 60 ... 70 ⁰ C for a period of 3 ... 6 hours.

The essence of the invention is therefore that fruit and / or vegetable products at a temperature of 15 ... 30 ⁰ C with an osmotic solution, which has an invert sugar content of 75. ··· 85 % treated, the osmosis solution being recirculated continuously flowing through the products and pumped out after 20-24 h and the resulting dry fruit-like products having a dry matter content of 60-75% either directly or after drying to a final moisture content - 25 % of the further processing are supplied.

The advantages of the method according to the invention are that the Kandierzeit is significantly shortened due to the continuous operation and by the immediate treatment with a highly concentrated Invertzuckerlösung and that it comes by working at low temperatures to save energy.

The continuous mode of operation enables an economic utilization of the osmosis solution, which is recirculated in a concentrated manner.

By the method according to the invention, products are obtained which are similar in appearance, composition and sensory properties to natural dried fruits.

Characteristic of these dry fruit-like products is the shrunken surface.

Further advantages are that by using the inverted sugar solution, the diffusion rate in the osmosis is increased and the fruit character of the dry fruit-like product is maintained. In addition, an ingredient-like composition is achieved as with the natural dried fruit, the product has a pleasant sweetness and its use in baked goods, a freshness-preserving effect is achieved.

Due to the low sucrose content of the osmosis solution due to the inversion, the crystallization of the sucrose, which leads to negative sensory properties, excluded. Sugar inclusions are avoided as far as possible by working at low temperatures. It is also advantageous that the dry fruit-like products obtained as a result of running non-enzymatic browning reactions, which are favored by the repeated use of the osmotic solution, a desired golden yellow to brown color.

The invention will be explained in more detail in the following examples.

Example 1: Dried fruits for use in the baking and long-life bakery industry

The washed and pretreated fruits, preferably cherries and plums, are placed in a Kandierbe- container and on Siebeinsätzen max. 5 cm high layered. As an osmotic solution inverted sugar solution with preferably 80 + _ 5% invert sugar at room temperature (variable 15 ... 30 ⁰ C) is used. This solution is added to the fruits and continuously circulated so that all fruits are covered and surrounded by a solution flowing around them. The circulated osmotic solution is simultaneously adjusted back to its starting level of invert sugar during its circulation. This process is finished after 20 ... 24 h, ie when the fruit has a dry matter content

y have reached 65 % . Then the osmotic solution is pumped out and the fruit still surrounded on all sides by the solution.

bottled in barrels and refrigerated until further processing.

In the bakery, the fruits are washed, separated from the sugar-containing water (syrup) by means of a sieve, then floated and used. The syrup may e.g. to be used as a pouring liquid in yeast dough production. During processing into filling compounds, the fruits are used directly and the recipe sugar key is lowered.

Example 2: Dried fruits for household use or snack mixes

The work-up is analogous to Example 1. After pumping the osmotic solution, the fruits are washed and dried after draining the adhering water. The drying is carried out initially for about 60 min on a vibrating screen at room temperature and then gently with air circulation at preferably 70 ⁰ C three to six hours. It is dried to a final moisture content of έ 25%. The drying time depends on the type of fruit and the size of the piece.

To prevent sticking the Tr.ockenfrüchte these can on a vibrating screen with sugar or similar. ' hygroscopic materials, dij2 food safe harmless be encased.

Claims (2)

invention claim 1. A process for producing a dried fruit product
Fruit and / or vegetable products by osmotic drying, characterized in that the pretreated, in particular washed and comminuted, optionally vorberervier- th products with a 75 · · · 85 % invert sugar osmotic solution at a temperature of 15 ... 30 ⁰ C treated be carried out with the osmotic solution in the circulation, the product flows through continuously, after 20 ... 24 h pumped and the resulting dry fruit similar products either directly with a dry matter content of 60 ... 75 % or after drying to a final moisture content of
£ 25 % of further processing will be supplied. 2. The method according to item 1, characterized in that the products having a dry matter content of 60 ... 75 % 50 ... 60 min at room temperature (15 to 30 ⁰ C variable) and then 3 ... 6h at 60 ... 70 ⁰ C gently to a final moisture content of r 25 ζ ⁷ »dried.