SE505893C2 - Prodn. of high bio-availability in whole oatmeal prod. - Google Patents

Abstract

The malting process of oat grains takes place over several days and at a lower temp. than with other meals, followed by careful drying at low temp. and milling. The malting process goes on for 4 to 6 days at a temp. below 15 deg.C. Soaking occurs for 15-20 hours in the temp. range of 30 to 45 deg.C.

Description

505 893 2 It has been known in the past that by wetting the whole grain grain for germination, the activity of enzymes, including phytase, can be increased. However, in order for a cereal grain to be used in flour production, the germ must not be larger than 5-10 mm. Under such circumstances, no major degradation of phytate occurs in the germination step, but it has been possible to demonstrate an increased phytase activity in wheat, grain and rye - but not in oats.

Attempts to grow oats and thereby increase phytase activity have been carried out by Bartnik & Szafranska 1987 (J. Cereal Sci. 5: 23-28). During germination up to 96 hours, the phytate contents were reduced by a maximum of 16%. Ashton and Williams 1958 (J. Sci. Food Agric. 9: 505-511) completely reduced phytate levels in oats by prolonged germination for 14 days.

However, Groningen was made so that the sprout does not grow out completely and thus the oatmeal cannot be used for flour production. The purpose of the invention is to solve the above-mentioned problems and to improve the mineral availability of oat products through a process which greatly increases the phytase activity in oatmeal. The invention is a solution to these problems. The problem solution is stated in the characterizing part of claim 1.

Figure 1 shows a fl fate diagram for an industrial malting process.

Figure 2 schematically shows the individual technical stations in malting processing.

The process for the production of oatmeal with high phytase activity consists of a new malting process as described below: (See also Figures 1 and 2).

S19 "opening (soaking) A ladle is filled with peeled oats and water with a temperature of 15-20 ° C is added. The uptake of water depends on the amount of water, pouring time and temperature. The water content increases rapidly and the coma's metabolic activity starts. CO is developed , which suffocates the grain at the same time as large amounts of O, are consumed.Efficient aeration is therefore necessary.The water is drained at regular intervals and the grains are added 0, from the air.The casting is stopped when the water content of the grains is 42-46% (shown by laboratory analysis) 505 893 5-] The casting is carried out in a large cylindrical vessel with a conical bottom, which is placed over the germination strip, so that the finished oats can be let down through the bottom valve.

In the casting tank there are pipes for supplying water and oats. Furthermore, annular pipes with nozzles for blowing air are mounted along the walls and mainly in the "cone".

Qmninacn After casting, the oats are transferred to germination chests, where the temperature and humidity are carefully controlled and regulated. Groningen takes 4-6 days and the root sprout that grows out of the oat grain is then generally 5-10 mm. During germination, heat, CO, and H 2 O are formed. For cooling the oat grains and transporting away CO, a lot of air is needed which is blown through the grains while they are growing. The temperature is kept at 11-12 ° C during germination. The following factors are checked and regulated automatically: * temperature * humidity 'air volume * time 5.1.

The grain is laid out on a perforated plate in an elongated box that is open at the top. Moist air is blown in from below through the base plates and further through the oats. The coffin is equipped with a turner with helical spirals which from time to time is run through the entire oat mass to get agitation.

Iotlinins The drying takes place on horizontal drying plates in a so-called cooling by blowing heated air (30 ° C) through. The drying lasts for about 1 day. The pre-dried oat malt passes through a malt cleaner where the sprouts are separated. The sprouts can give a certain off-taste, so they are removed from the oatmeal. However, they are very rich in B vitamins and proteins, making them valuable as food for animals.

On a laboratory scale, the production process has been carried out as follows: Whole, gently peeled oat grains are soaked for six hours in water at 25 ° C. Water is allowed to stir for ten minutes. The oatcomb is spread in a single-grain layer on a tray, which is covered with a laminated paper, the underside of which is plastic-coated. The oat grains are dried to 42-47% moisture content at 30 ° C in a kt genuine heating cabinet for one hour. The oat grains are covered with a perforated plastic-coated filter paper, which lets air through but at the same time retains the appropriate moisture content in the oat grains. After a few hours, lift off the covering filter paper and spray water on the oat grains. The filter paper is reloaded. Groningen can be done for 3-4 days in a kt marriage heating cabinet at 11-15 ° C. Three times a day, the grains are sprayed with water and the trays that stand on different shelves in a fl marital heating cabinet to be raised in height one step so that the germination is even and no accumulation of metabolites takes place. When the sprouts are 5-10 mm long after 3-4 days, the filter papers are removed and the grains are dried for one day at 30 ° C in a real heating cabinet.

Both germination and drying steps take place during air circulation. They are dried, the whole seaweed is ground into a flour.

The flour thus produced has been shown to have a high phytase activity. The phytase activity in the flour was studied in the following experiments. A suspension of 1 g of malted oatmeal in 10 ml of deionized water was incubated overnight (17 hours) at 20, 37, 38, 39, 40 and 41 ° C, respectively. The pH was determined initially and at the end of the incubation. The results are given in Table 1. Soaking the flour in water at 37-40 ° C overnight resulted in 98% phytate reduction compared to the original content of the untreated, peeled oatmeal.

For comparison, phytate degradation was examined in oats, wheat, barley and rye malted at 15 ° C, which is normally used germination temperature in malting processes for cereals. rye. Under these conditions, phytate degradation in oats was at most 64%. (See Table 2.). 505 893 5 Oatmeal does not appear to be prone to rancidity and may have a viscosity-exfoliating effect in gruels.

The oatmeal as described above can be added in a wet food process under suitable temperature conditions (37-40 ° C), for example in the preparation of gruels or breakfast cereals. 505 893 TABLE 1 Phytate reduction in oat grains melted for 5 days at 11 ° C and dried at 30 ° C overnight. The dried grains were ground into flour and incubated at different temperatures for 17 hours.

. E I l.

(° C) (% of the original content of the grain) 20 94 37 97 38 98 39 98 40 98 41 95 505 893- TABLE 2 Pyata extraction in grains melted for 30-40 hours at 15 ° C, ground into flour and incubated at pH 5, 55 ° C. (min) (% of original content in the grain) 16 53 57 63 Oats §sssa = šssæaø šsssac šëësø assæa ~ asæ2a ~ 2 Vete .ä UI O Kom šææas

Claims (1)

1. 505 893 8 CLAIM PROCEDURE Process for increasing the bioavailability of minerals in products based on whole oat grains is characterized by a malting process of the grains which extends over a period of 4 to 6 days and at a temperature of below 15 ° C. Claim 1, characterized in that the incubation - the soaking for high phytate reduction works with an incubation temperature in the range of 30 ° to 45 ° C. Process according to claims 1 and 2, characterized in that the incubation time for reduction of phytates is in the range 15 to 20 hours. Process according to Claims 1 to 3, characterized in that the whole oat grains are gently peeled before malting. A method according to claims 1 and 4, characterized in that the peeled oat grains are moistened for 4 to 8 hours. Method according to claims 1 and 5, characterized in that the oat grains are aerated continuously while they germinate. Method according to claims 1 and 6, characterized in that the malt sprout is removed from the ready-dried oat grains to avoid any off-taste of the sprouts.