Double suction deoxidizer and its application in coffee

Double suction deoxidizer and its application in coffee

First, preface

Coffee, originated in Ethiopia in tenth Century, was welcomed by the people all over the world with its unique aroma and romantic characteristics.

In the process of roasting, coffee produces a large number of CO2 and aromatic gases. But at the end of the roasting, the CO2 and the aromatics began to lose. Over time, coffee deteriorated, the aroma was lost, and the taste deteriorated because of the chemical changes in the coffee beans and the oxidation reaction caused by contact with the air.

There are four techniques for the preservation of coffee: (1) the replacement of inert gas (N2), (2) vacuum packing, (3) exhaust vacuum tube, (4) deoxidizer. This paper mainly introduces the preservation method of deoxidizer.

Second, preservation technology of deoxidizer

Deoxidizer has been used in cakes, pancake, and other raw dough food preservation, it has anti mildew, anti discoloration and anti oxidation effect. Unlike ordinary food, coffee has a complex relationship between the quality and quantity of its aromatic substances and produces a large amount of CO2 gas. As soon as the coffee (beans) roasted, it began to produce CO2, and lasted for a long time, causing the coffee packaging to be prone to expansion, rupture and so on. So the use of deoxidizer to preserve coffee is not only to remove oxygen, but also to remove CO2.

（1） The deoxidizer be used in coffee should to meet the following conditions:

1 can completely remove oxygen, and can absorb CO2

2 does not cause a change in the aroma and taste of the coffee, and does not produce the smell.

3 easy to use, high efficiency

4 the price is cheap

5 even if eating is not dangerous

（2） The performance of the deoxidizer in coffee:

1, the aroma and taste of coffee is very subtle. If we simply remove oxygen, it may destroy the balance between aromatic substances. So in order not to destroy the aroma of coffee, it is better to remove oxygen gently.

2 because the coffee (bean) roasted will produce a large amount of CO2, so the deoxidizer is enough to absorb all the CO2.

The time of roasting of coffee (beans) is different, and the amount of CO2 produced is different. The roasted great strength Iced coffee (beans) produce 400-500ml CO2 gas per 100g, and the baking medium strength hand milled coffee (beans) produces CO2 gas of 200-300ml per 100g. The gas generated in the first month of preservation accounts for 70% of the total gas.

（3）Special deoxidizer for coffee (double sucking deoxidizer)

Special deoxidizer satisfying (1) and (2) conditions for coffee can absorb oxygen and CO2 at the same time. According to the quantity produced by CO2, four different types of double sucking deoxidizer for coffee are formulated from the quantity of coffee in 100g-1kg.

Table 1，model number and model number of double sucking 

Third. Experiment of double sucking of coffee beans

1、test method

200g just baked coffee bean and E-500 double suction type deoxidizer were sealed in the barrier bag with aluminum foil protection layer， and set up a control area without deoxidizer. There are more CO2 in the control area, so gas should be released at the right time so as not to break the package. The test was carried out at 25 centigrade for 3 months, and the content of CO2 in the bag was measured once a month, and the sensory evaluation was carried out.

2、test result

（1）The amount of CO2 in the roasted coffee bean package changes over time as shown in Figure 1

 Figure 1  the amount of CO2 in the roasted coffee bean package changes with time

① Double sucking sample: the CO2 of coffee beans was absorbed within 2 months, and the absorption state lasted for a long time, and the absorption rate began to slow down after 2 months.

② The control sample: a large amount of CO2 gas is produced, and the bag expands ，and on the twentieth day the bag expands to the extent to which it will break. Gas is pumped out and the amount of gas produced is obtained: first months produce 400ml, 2 months produce a total of 500ml, 3 months to produce a total of 550ml.

（2）The results of sensory test are shown in Table 2.

Table 2   sensory test results of roasted coffee beans

evaluate   aroma: 3: not oxidizing and smelly 2: slightly oxidizing and stinking 1: complete oxidation and odor

           taste: 3: close to roasting        2: a rancid taste                  1: low taste

①Double sucking sample: after 3 months, the aroma and taste of the coffee beans are similar to those at the end of the roasting.

②The control sample: first months, the appearance of oxidation and odor, the decrease of aroma. The taste becomes worse every day, and it is obviously worse in second months.

Appendix: an example of double suction deoxidizer in company

（1）sample

The mixture of iron powder 2G and NaCl 1g was mixed with calcium hydroxide (25 mesh), water and gypsum powder (100:32:25) mixture into a breathable inner packaging bag, and made into double suction deoxidizer samples.

The samples were wrapped with 500g roasted coffee beans in the KOP/PE composite membrane packaging bag, and the 500g roasted coffee beans were only wrapped in KOP/PE composite film bag, called the contrast sample No. 1. The 500g baking coffee beans were packed in paper bags, called the contrast sample No. 2, and the three samples were kept at 25 degrees.

（2）test result

Table 1  changes in the amount of oxygen and carbon dioxide over time

Note: because the coffee beans will produce CO2, and the packing bag is sealed, the contrast sample No. 1 bag is expand and is about to split.

Table 2  quality of coffee beans stored for 45 days