JPS6251962A - Treatment of juice cake of citrus fruit - Google Patents

Abstract

PURPOSE:To improve the dehydration efficiency of squeezed juice cake, to decrease the water-content of the cake and to improve the yield of peel water, by adding slaked lime to the squeezed juice cake of citrus fruit and heating the mixture at a specific temperature. CONSTITUTION:A squeezed juice cake of citrus fruit is added with slaked lime and dehydrated by compression. In the above process, the mixture is heated at 50-100 deg.C, preferably 60-90 deg.C for 30sec-10min after the addition of slaked lime.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for treating citrus juice residue, which is a by-product when extracting fruit juice from citrus fruits.〇 [Prior Art] Citrus fruit juice For the method of obtaining fruit juice by squeezing, the US FMC
There are several methods, such as the method of squeezing the juice using an in-line type juicer, and the method of peeling the skin with a peeler and squeezing it with a pulper finisher, but with either method, the extraction rate is about 2J
~Otsuθ% is only about 4tO~7! % of juice lees is produced as a by-product. Since this squeezed lees still contains a large amount of water, it is treated with a treather to evaporate the water and make peel. Generally, industrially, the juice lees is dried using a dryer such as a rotary dryer using a direct flame burner using heavy oil.

In order to save the thermal energy of single-layer oil during this drying process, it is desirable to reduce the moisture content of the cake in advance and to make it easier to remove the moisture contained in it. In other words, in citrus fruits, the pericarp makes up a large proportion of the fruit (contains a colloid substance called pectin, so the juice lees in particular has a sticky texture, and when pressed, However, it is difficult to separate the moisture. Therefore, if it is dried as it is, the heat will not pass through properly (it will be difficult to remove the moisture, and excessive heat energy will be consumed, which is undesirable).

As a countermeasure to this problem, there is the so-called Liming method, in which slaked lime or slaked lime in the form of lime milk is boiled and then pressed. In other words, add slaked lime to the squeezed lees in advance,
Add ~0.1<wt% and mix, l! After reacting at room temperature for ~20 minutes, the juice is squeezed, during which time the hydrophilic pectin in the squeezed lees reacts with the slaked lime and transforms into hydrophobic pectin.

This causes the so-called syneresis phenomenon, where water easily separates from the lees.
As a result, the fruit juice mixed with the stone components contained in the squeezed lees, such as sugar, minerals, amino acids, and vitamins, is easily separated.

The fruit juice separated here is called beer water.
It is a secondary fruit juice whose acid components have been neutralized with slaked lime - Br1x
/0 to /4t, and is a useful resource that can be used as a raw material for fermentation or as a stock solution for molasses syrup.

[Problem that the invention seeks to solve]

Juice from citrus fruits? In the process of liming the squeezed lees, which is a by-product of the process, and further squeezing the juice, we aim to increase the yield of beer water and reduce the moisture content of the lees. This has a large impact on the saving of thermal energy and has important industrial significance.In other words, it is desired to improve the dewatering efficiency of the lees, which will lead to a reduction in the moisture content of the lees and an increase in the yield of beer water.

[Failure to solve the problem]

The present inventors have conducted various studies with the aim of further improving the effect of liming, reducing the moisture content of the lees, and increasing the yield of beer water. The present inventors investigated in more detail the actual situation of liming that is generally carried out in citrus juice factories, and found that when liming, 3O-
By using the extremely simple method of heat treatment at IO'0℃, the amount of beer water obtained can be reduced compared to conventional methods! In addition, the moisture content of pressed Wagyu beef can be reduced to approximately 69%, compared to the conventional method where the juice lees has a moisture content of approximately z3%, which is reduced to approximately 25% by pressing after liming. I learned.

The present invention is based on this knowledge (1) The present invention is characterized in that in the process of adding and mixing slaked lime to citrus juice lees and then compressing and dehydrating it, the slaked lime is heated to 50 to 700°C after the slaked lime is added and mixed. This is a method for processing citrus juice residue.

Citrus fruits to which the present invention is applied include, in addition to summer mandarin oranges, lemons, Valencia oranges, navel oranges, hesaku-Iyokanichi yuzu, sudachi, and kapos. It can be used for processing the squeezed lees. Also - among these citrus fruits for eggplant.

Extraordinary small balls or fruits that occur in the early stage of ripening - "Fruits that have fallen through the filtration period or have been thinned are unsuitable for extracting juice, but after crushing the whole fruit, liming and dividing into lees and beer water or molasses. , 27D manufactured products.Of course, the present invention can also be used in this case as well.

In the present invention, citrus juice can be squeezed according to a conventional method.

Slaked lime is added to and mixed with this squeezed lees. This addition and mixing can be carried out by any means, and slaked lime in the form of milk of lime can also be used.

The addition amount of digested ash is preferably about 0.3 to 0.6% by weight.

Next, in the present invention, any suitable heating means can be used for heating the squeezed lees after adding and mixing slaked lime. As for the heating temperature, no effect can be expected at temperatures below 50°C, and temperatures above 00'C practically require special equipment for heating. It's not only not economical, but it doesn't show any special effects even at high temperatures.
is preferred.

Regarding the heating time, if the temperature is high, a short time is sufficient (30 seconds to θ minutes).In general, in industrial equipment, a cylindrical stirring shaft with a steam keratin is used. However, in order to further improve the heating effect and crushing efficiency, the lees and slaked lime are mixed while injecting live steam from several places in a closed cylindrical screw conveyor with a rotating shaft. It is desirable to quickly raise the temperature of the entire lees to a predetermined temperature and heat-process it for an appropriate amount of time.

The juice lees heat-treated as described above is pressed using a screw press to obtain beer water and press cake.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 Moisture content of squeezed lees C obtained by subjecting unshiyuumigan to an in-line juice extraction machine ♂3. /j%1/000Ky, add it to slaked lime 39 of the food additive standard (after stirring, use a closed screw conveyor with a steam injection port, for - minutes?
It becomes θ°C! Minutes? Steam was blown into the mixture to heat it at 0.degree. C., and then it was charged and squeezed at a flow rate of 2,700 Kf/hour using a Shoda Press screw press to obtain a press cake and beer water.

On the other hand, as a control, the same squeezed lees 1000Ky as above was used except that no steam was blown.

Press cake and beer water were obtained.

The results are shown in Table 1 below.

Table 1 As clearly shown in Table 1, when the heat treatment according to the present invention is performed, the water content of the press cake decreases, the extraction rate of beer water increases, and at the same time, the flexibility of the beer water increases. The solid content yield also increased by 7+[]L, indicating that the dehydration efficiency of the squeezed lees was further improved.

Example 2 Juice lees obtained by subjecting summer mandarin oranges to an inline type juicer
Moisture ♂ 7.02 Section) / 000 [Add slaked lime gK of the food additive standard to 7] (after stirring - use a closed screw conveyor with a steam injection port).

The temperature reached 70°C in 3 minutes, and steam was blown to heat it at 70°C in the evening, and the mixture was charged with a drawstring Shoda press split screw press at a flow rate of 270,097 hours and pressed - press cake and beer. Got water.

On the other hand, as a control, the same squeezed lees ioo as above.

Regarding Ky, except for the condition that no steam is blown.

(Operated as above - press cake and beer water were obtained.

The results are shown in Table 2.

Table 2 From Table 2, when the heat treatment according to the present invention is carried out, the water content of the pressed cake decreases, the extraction rate of beer water increases, and at the same time, the yield of soluble solids in beer water also increases. It can be seen that the dehydration efficiency of the soup lees has further improved.

〔Effect of the invention〕

In the industry of extracting fruit juice from citrus fruits, the problem is how to dispose of the juice residue, and saving heat energy for drying it into peels is an economically important factor.

According to the present invention, by applying a simple method of instant heating in the liming process, it is possible to dehydrate the squeezed lees efficiently, reduce the water content of the lees, and increase the yield of beer water. Economically valuable results can be obtained.

Claims (1)

[Claims] In the process of adding and mixing slaked lime to citrus juice residue and then compressing and dehydrating it, 50 to 1
A method for processing citrus juice residue, which comprises heating it to 00°C.