JP2005278638A - Method for producing frozen yoghurt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing frozen yoghurt having high preservation stability and excellent flavor even without using a food additive such as thickening polysaccharides derived from plants. <P>SOLUTION: The frozen yoghurt has solid content increased by the addition of viscous polysaccharides produced by lactic acid bacterium, and fat and/or sugar. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing frozen yogurt having high storage stability and a smooth texture. More specifically, the present invention relates to the prevention of coarsening of ice crystals during storage of frozen yogurt and imparting a rough texture by using lactic acid bacteria that produce a large amount of viscous polysaccharides and increasing the solid content.

  The frozen yogurt of the present invention refers to a frozen dessert to which fermented milk is added, and includes ice creams to which fermented milk is added.

  Conventionally, frozen yogurt has been added with plant-derived thickening polysaccharides such as pectin, guar gum or locust bean gum in order to prevent coarsening of ice crystals during storage. However, these thickening polysaccharides deteriorated the melting of frozen yogurt, and the freshness peculiar to yogurt was also impaired. On the other hand, in the case where these thickening polysaccharides were not added, the smooth texture unique to ice creams was impaired as the storage period increased.

On the other hand, although the stabilizer for fermented milk products which uses the phosphorylated polysaccharide which lactic acid bacteria produce as an active ingredient is disclosed (refer patent document 1), the food texture in the thaw state is improved, but at the time of eating and drinking The texture in the (frozen state) was not sufficiently improved.
Japanese Patent Laid-Open No. 8-222060

  Accordingly, an object of the present invention is to provide a frozen yogurt that has a smooth texture and is well melted in the mouth.

  The present inventor has paid attention to the fact that certain lactic acid bacteria produce many viscous polysaccharides outside the cells during fermentation, and by adding viscous polysaccharides derived from lactic acid bacteria to increase the solid content, a smooth texture is achieved. It has been found that it is possible to produce frozen yogurt that has good meltability in the mouth, and the present invention has been completed.

That is, the present invention is (1) a frozen yogurt containing a viscous polysaccharide derived from lactic acid bacteria and having a solid content of 38% or more,
(2) Frozen yogurt as described in (1) above, containing 0.002% (w / w) or more of a viscous polysaccharide derived from lactic acid bacteria,
It is related to.

  According to the present invention, by vigorously utilizing the viscous polysaccharides produced by lactic acid bacteria, the storage stability is high and flavorless even without using food additives such as plant-derived thickening polysaccharides. There is an advantage of producing good frozen yogurt.

  The pre-fermentation mix consists of non-fat milk solid ingredients such as skim milk powder, fat ingredients such as cream, and sugar ingredients such as sugar, which increases the solid content of the final frozen yogurt, thereby improving storage stability Increased. The solid content is preferably 38% or more, and more preferably 40% or more.

  Hereinafter, the present invention will be described in detail.

Conventionally, among plant-derived thickening polysaccharides used as thickeners, pectin is a polysaccharide mainly composed of partially methylated polygalacturonic acid, and locust bean gum and guar gum are galactomannans. Is a polysaccharide mainly composed of On the other hand, polysaccharides derived from lactic acid bacteria are polysaccharides composed of glucose, galactose, and rhamnose, and may be partially phosphorylated. As a characteristic, polysaccharides derived from lactic acid bacteria are characterized by high stringiness compared to thickening polysaccharides derived from plants.
Lactic acid bacteria vary greatly in the amount of polysaccharides produced outside the cells. In the industrialization of fermented milk, conventionally, in consideration of productivity, it has been common to select a strain that produces relatively little polysaccharide.

  Streptococcus lactis, Lactococcus lactis, Lacococcus cremoris, etc. are known as strains producing a large amount of viscous polysaccharides. It is preferable to select a strain producing viscous polysaccharides from lactic acid bacteria used in milk. When added, the amount added is preferably 2.0 mg or more per 100 g of product. As a result of screening from a number of lactic acid bacteria using the productivity of viscous polysaccharides, flavor characteristics as frozen yogurt and the like as indicators, the present inventors have found that Lactobacillus bulgaricus OLL 1073R-1 strain (FERM P-17227) and Streptococcus Thermophilus OLS 3290 strain (FERM P-19638) was selected. In order to maximize the production of polysaccharides, the fermentation temperature was 37 ° C.

  In general, when making fermented milk, lactic acid bacteria are inoculated into a mix of non-fat milk solid content of 8 to 16% and fermented and cultured. However, when frozen yogurt is produced using such fermented milk, the final solid content is about 30 to 36%, which is lower than normal ice cream (final solid content is about 38 to 43%) And there will be no smoothness. Therefore, in order to give smoothness, it was a usual method to add plant-derived thickening polysaccharides such as pectin.

In order to solve this problem, a part of saccharides such as fat and sugar was added to fermented milk using lactic acid bacteria producing viscous polysaccharides so that the final solid content was increased. The addition to the fermented milk may be performed before fermentation, but may be added after the end of fermentation so that the final solid content becomes high. In addition, dietary fiber, sweeteners, flavors, and the like can be added.
Dietary fibers include poorly water-soluble dietary fibers such as guar gum, mannan, seaweed polysaccharides (alginic acid, laminarin, fucoidan), chemically modified polysaccharides, chemically synthesized polysaccharides, and cellulose, hemicellulose, pectin, polydextrose, lignin, inulin And water-soluble dietary fiber such as chitin.
Sweeteners include oligosaccharides (isomaltooligosaccharide, fructooligosaccharide, galactooligosaccharide, palatinose, coupling sugar, soybean oligosaccharide, maltooligosaccharide, dairy oligosaccharide, xylo-oligosaccharide, trehalose, etc.), artificial sweetener (saccharin, aspartame) , Acesulfame potassium, sucralose, etc.), sugar alcohols (erythritol, xylitol, sorbitol, palatinit, maltitol, lactitol, mannitol, etc.), natural sweeteners (stevia, glycyrrhizin, Luhan fruit, thaumatin, etc.), sugars (glucose, fructose, galactose, Maltose, sucrose, lactose, etc.).

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated, this invention is not limited by this.

[Example 1] Manufacture with high-productivity lactic acid bacteria with viscous polysaccharides 51.0% defatted concentrated milk, 17.5% cream (45 wt% fat) and 8.0% sugar are dissolved in warm water, homogenized, and then heat sterilized with a heat exchanger, etc. did. This was cooled to 40 ° C., inoculated with L. bulgaricus OLL 1073R-1 strain and S. thermophilus OLS 3290 strain, and fermented at 37 ° C. for 5 hours. After completion of the fermentation, after cooling, the card produced by a homogenizer or the like was pulverized and used as a fermented milk mix.
On the other hand, the ice cream mix is 29.5% non-fat concentrated milk, 42.7% cream (45 wt% fat) and 18.9% sugar dissolved in warm water, 20% sweetened egg yolk 4.0% (Sanshu Foods) ) Was added, homogenized, heat sterilized with a heat exchanger or the like, and cooled. 40 parts of fermented milk mix is mixed with 60 parts of this ice cream mix, frozen at 20% overrun in a continuous freezer, filled into a paper container, rapidly cured at -40 ° C, and stored in a freezer at -20 ° C or lower. Frozen yogurt having a solid content of 43% (containing a viscous polysaccharide of 0.002% or more) was obtained.

[Comparative Example 1] Manufacture with low-viscosity polysaccharide-producing lactic acid bacteria Non-fat concentrated milk, cream (fat content 45 wt%) and sugar were dissolved in warm water, homogenized, and then heat sterilized with a heat exchanger or the like. This was cooled to 40 ° C. and manufactured by Meiji Dairies Co., Ltd. “Lactic acid bacteria consisting of L. bulgaricus 1106 strain and S. thermophilus 3074 strain isolated from Probio Yogurt LG21 (low production of viscous polysaccharides used in ordinary fermented milk) Inoculated and fermented for 5 hours at 37 ° C. After completion of fermentation, after cooling, the card produced by a homogenizer or the like was pulverized and used as a fermented milk mix.
On the other hand, the ice cream mix is 29.5% non-fat concentrated milk, 42.7% cream (45 wt% fat) and 18.9% sugar dissolved in warm water, 20% sweetened egg yolk 4.0% (Sanshu Foods) ) Was added, homogenized, heat sterilized with a heat exchanger or the like, and cooled. 40 parts of fermented milk mix is mixed with 60 parts of this ice cream mix, frozen at 20% overrun in a continuous freezer, filled into a paper container, rapidly cured at -40 ° C, and stored in a freezer at -20 ° C or lower. Frozen yogurt with a solid content of 43% (viscous polysaccharide less than 0.002%) was obtained.

The frozen yogurt shown in Example 1 and Comparative Example 1 was subjected to an accelerated test at −14 ° C. constant temperature and a heat shock test at −5 ° C. for 2 hours + −20 ° C. for 4 hours as a storage stability confirmation test. The sensory evaluation was carried out (evaluation of smoothness by coarsening of ice crystals). The storage test results are shown in Table 1. As is clear from this result, Example 1 containing the viscous polysaccharide produced by lactic acid bacteria is clearly preserved compared to Comparative Example 1 (containing polysaccharide but almost no viscosity) containing almost no viscous polysaccharide. Stability was improved.
The viscosity of the yogurt shown in Example 1 and Comparative Example 1 is shown below. The measurement was performed using a B-type viscometer (manufactured by Tokyo Keiki Co., Ltd., type BM, No. 3, rotor, 60 rpm) at an acidity of 0.65% and a temperature of 4.0 ° C. The fermented milk of Example 1 was 220 mPa · s, and the fermented milk of Example 1 was 80 mPa · s. It can be seen that the viscosity of Example 1 is higher.

HS: Heat shock test at −5 ° C. for 2 hours + −20 ° C. for 4 hours −14 ° C .: accelerated test at −14 ° C. constant temperature ◎: Very smooth and good, ○: Smooth and good, Δ: Slight roughness

(Comparative Example 2) Highly viscous polysaccharide-producing lactic acid bacteria, low solid content Non-fat concentrated milk prepared with non-fat milk solid content of 15.1% was heat sterilized, then cooled to 40 ° C and cooled to L. bulgaricus OLL 1073R -1 strain and S. thermophilus OLS 3290 strain were inoculated and fermented at 37 ° C for 5 hours. After culturing and cooling, the curd produced with a homogenizer or the like was pulverized and used as a fermented milk mix. On the other hand, the ice cream mix is 14.8% non-fat concentrated milk, 29.5% cream (45 wt% fat), 8% sugar, 13.3% Lightes II and 2.67% honey (80% solids) in warm water. Dissolved and added with 20% sweetened egg yolk 3.2% (manufactured by Sanshu Foods), homogenized, heat sterilized with a heat exchanger or the like, and cooled. These are mixed at 75:25, frozen in a continuous freezer at an overrun of 20%, filled into a paper container, rapidly cured at -40 ° C, stored in a freezer at -20 ° C or lower, and with a total solid content of 37%. Frozen yogurt (containing 0.002% or more viscous polysaccharide) was obtained.

(Comparative Example 3) No stabilizer added, high solid content raw milk 13.0%, skim concentrated milk 25%, cream 35.0% (fat content 45 wt%), sugar 10.1% and starch syrup (solid content 75%) 5.0% was dissolved in warm water, 20% sweetened egg yolk 2.4% (manufactured by Sanshu Foods) was added, homogenized, heat sterilized with a heat exchanger or the like, and cooled. This mix was frozen with a continuous freezer at an overrun of 20%, filled into a paper container, rapidly cured at -40 ° C, and stored in a freezer at -20 ° C or lower to obtain an ice cream with a total solid content of 41%.

(Comparative Example 4) No stabilizer added, low solid content 25.9% non-fat concentrated milk, 31.4% cream (45 wt% fat), 10% sugar and 5.3% starch syrup (solid content 75%) After adding 20% sweetened egg yolk 2.4% (manufactured by Sanshu Foods), the mixture was homogenized, heat sterilized with a heat exchanger or the like, and cooled. This mix was frozen in an overrun 20% with a continuous freezer, filled into a paper container, rapidly cured at -40 ° C, and stored in a freezer at -20 ° C or lower to obtain an ice cream with a total solid content of 37%.

  Table 2 shows the storage stability depending on the difference in solid content when the viscous polysaccharide is included. The ice creams shown in Example 1 and Comparative Examples 2, 3, and 4 were subjected to an accelerated test at -14 ° C constant temperature and a heat shock test at -5 ° C for 2 hours + -20 ° C for 4 hours as a test for confirming storage stability. The storage stability was sensorially evaluated. As is clear from this result, the storage stability of Example 1 containing viscous polysaccharides produced by lactic acid bacteria and having a high solid content was clearly improved as compared with Comparative Examples 2, 3, and 4.

HS: Heat shock test at −5 ° C. for 2 hours + −20 ° C. for 4 hours −14 ° C .: accelerated test at −14 ° C. constant temperature ◎: Very smooth and good, ○: Smooth and good, Δ: Slight roughness , ×: Strong and rough

  By using viscous polysaccharides produced by lactic acid bacteria and increasing the solid content, it is possible to produce frozen yogurt with high storage stability and flavor without adding food additives.

Claims (2)

Frozen yogurt containing viscous polysaccharides derived from lactic acid bacteria and having a solid content of 38% or more. The frozen yogurt according to claim 1, comprising 0.002% (w / w) or more of a viscous polysaccharide derived from lactic acid bacteria.