Quality Characteristics Of Yogurt Research Articles

Effects of novel autochthonous starter cultures on quality characteristics of yoghurt

Abstract In the study, in order to develop novel starter cultures, three types of yoghurt were produced with different combinations of autochthonous yoghurt bacteria and the samples were investigated in terms of fermentation, microbiological quality, physicochemical properties (pH, acidity, water-holding capacity, apparent viscosities, and rheological properties), organic and benzoic acid contents, and sensory properties during 28 days. Lactobacillus delbrueckii subsp. bulgaricus content of all samples was between 7.29 and 8.58, and Streptococcus thermophilus content was between 8.03 and 9.02 log CFU/g during storage. Yoghurt type and storage time statistically affected pH, acidity, water-holding capacity, apparent viscosity, rheological properties, organic and benzoic acid content, and some sensory parameters. The general acceptability scores of the probiotic, traditional, exopolysaccharide, and control samples during storage were 8.27, 7.82, 7.53, and 7.47 respectively. Moreover, the results revealed that the strain combinations for probiotic, traditional, and exopolysaccharide yoghurt samples can be used as novel starter cultures for yoghurt production.

Formulation and evaluation of a probiotic drink fortified chlorella for enhanced health benefits

Probiotics are microorganisms that have benefits when consumed, they can be found in yogurt. Yogurt commercially lack protein; the addition of chlorella is a solution due to chlorella contains high protein. The research aimed to determine the effect of chlorella fortification on the quality characteristics of yogurt and the best concentration of chlorella addition in the manufacturing of yogurt. The experimental method using a non-factorial Completely Randomized Design (CRD) consisting of 4 treatment levels: without the addition of chlorella (PC0), 0.75% of chlorella (PC1), 1% of chlorella (PC2), and 1.25% of chlorella (PC3). The parameters tested in this research were hedonic testing and quality, chemical composition, physical properties, and microbiological assay. The results showed that yogurt fortified with 1% chlorella was most favorable by consumer acceptance, with organoleptic characteristics: green and thick color, slightly characteristic aroma of chlorella, and slightly sour taste typical of chlorella. Meanwhile, the proximate composition of this yogurt contains 81.26% moisture, 3.77% protein, 2.30% fat, 0.89% ash, 1.47% fiber; physical properties of pH 4.65, Aw 0.75, viscosity 205.85 cP; and microbiological value of acid total 1.95%, and lactic acid bacteria 2.1×107 cfu/g. Therefore, the yogurt chlorella is suitable for consumption and can enhance health benefits.

Instant stevia powder as a novel potential additive for enhancing nutritional value and quality characteristics of yogurt.

The online version contains supplementary material available at 10.1007/s13197-023-05892-z.

Effects of mulberry pomace polysaccharide addition before fermentation on quality characteristics of yogurt

Mulberry pomace, a by-product of mulberry juice processing, is rich in natural bioactive substances including polysaccharides and polyphenols and is useful for the production of functional foods. As such the effects of mulberry pomace polysaccharide (MPP) on physicochemical, textural and microstructural features of yogurt during cold storage were investigated. MPP was incorporated into reconstituted skim milk at 0% (control), 0.5%, 1.0% and 1.5%, respectively and then fermented to yogurt and stored at 4 °C for 28 days. The color, pH, titratable acidity, syneresis, rheology, texture and microstructure of yogurt samples were analyzed. The addition of MPP before fermentation dose-dependently affected the pH value and titratable acidity of yogurt samples such that the addition of 0.5% MPP showed the most significant effect in reducing syneresis, increasing gel strength and viscosity, and improving texture and microstructure of yogurt. The results indicate that the appropriate amount of MPP can effectively improve the gel properties and physicochemical parameters of yogurt, and MPP played an important role in the yogurt quality improvement by mulberry pomace.

Quality Characteristics of Yogurt Added with Karamunting (Rhodomyrtus tomentosa) Aqueous Extract As Natural Colorant and Source of Antioxidant.

The aims of this research are to determine the effect of the concentration addition level of karamunting (Rhodomyrtus tomentosa) fruit extract on the quality of yogurt during 9 d storage period to increase the functionality of yogurt as a probiotic food, a source of antioxidants and the use of karamunting as a natural colorant for food. This research used a completely randomized design consisting of two factors, that is the concentration of karamunting fruit extract which consisted of 4 addition levels (0%, 12%, 15% and 18% w/w) and the storage period of yogurt which also consisted of 4 levels (0 d, 3 ds, 6 d and 9 ds). The parameters that have been observed in this research were pH, total acid, water content, fat content, protein content, color analysis, antioxidant activity and organoleptic tests (aroma, taste, viscosity and color) of the yogurt. The results showed that karamunting fruit extract had a significant effect on pH, total acid, color L*, a* and b*, and organoleptic (aroma, viscosity and color) of the yogurt, but had no significant effect on water content, fat content, protein content and flavor of the yogurt. Storage period had a significant effect on pH, total acid, protein content, color L*, a* and b*, and organoleptic (aroma, taste, viscosity and color) of the yogurt, but had no significant effect on water content and fat content of the yogurt. The addition of 18% (w/w) karamunting fruit extract and 9 d of storage period resulted in yogurt with the characteristics as follows pH 4.2; total acid 1.57%; water content 87.05%; fat content 3.66%; protein content 2.7%; color L* 72,24; a* 8.28; and b* 9.38 and organoleptic (aroma, taste, thickness and color) which were quite favorable, as well as a strong antioxidant activity value of 85.35 ppm IC50.

Quality Characteristics of Yogurt with Different Levels of Cranberries Powder Addition of Different Particle Sizes

ABSTRACT The aim of this study was to evaluate the influence of cranberries powder (0, 0.25%, 0.5% and 1%) of different particle size (<300 µm and 300–500 µm) on the yogurt physicochemical, rheological, textural and sensory characteristics. Results indicated that the addition of cranberries improved the syneresis and water-holding capacity of the yogurt samples, increased all the rheological parameters (G’, G” and η) and decreased the color L* and b* values. The hardness, chewiness and gumminess increased while adhesion, stickiness and cohesivity of the yogurt samples decreased. The best sensorial samples were those up to 0.50% cranberries addition. According to the results obtained, the cranberries powder with 300–500 µm can be successfully used as a replacer for synthetic dyes and also may be used as an improver for the yogurt rheological properties.

Effect of the Addition of Whole and Milled Flaxseed on the Quality Characteristics of Yogurt.

The present study aimed to analyze the effect of the addition of whole and milled flaxseed on the quality characteristics of yogurt. In the first stage of the research, the optimal dose of flaxseed was determined. In the second stage of the research, it was assessed whether the selected qualities of yogurt were affected by the form of flaxseed (whole or milled) and the time of addition (before or after fermentation). The yogurts obtained were stored at 5 °C for 21 days, and the changes in active acidity, apparent viscosity, syneresis, and the number of yogurt bacteria were determined. The results of the second stage of the study were subjected to two-way analysis of variance (ANOVA) (p < 0.05). The study showed that the addition of milled flaxseed to yogurts in the amount of 1% was optimal. Time and form of flaxseed supplementation significantly influenced the changes in active acidity, apparent viscosity, and syneresis in the tested yogurts. The addition of flaxseed did not significantly change the content of yogurt bacteria. The results indicate that to achieve increased apparent viscosity and reduced syneresis, it is more advantageous to use milled flaxseed rather than whole flaxseed.

블루베리 분말을 첨가한 요거트의 항산화 활성과 품질 특성

블루베리 분말을 첨가한 요거트의 항산화 활성과 품질 특성

Quality characteristic and antioxidant activity of yogurt containing olive leaf hot water extract

ABSTRACT The objective of this study was to determine the antioxidant and quality characteristics of yogurt containing olive leaf hot water extract (CON: 0, OLY1: 0.1, OLY2: 0.2, and OLY4: 0.4% (w/v)) stored at 4°С for 15 days. After storage, the lactic acid bacteria count showed no significant difference between yogurt samples either in the presence or absence of olive leaf extract (p > 0.05). The total phenolic content, DPPH radical scavenging activity, and reducing power increased upon increasing the content of the olive leaf hot water extract. Oleuropein was found to be the most abundant phenolic compounds present in olive leaf, and the oleuropein content in OLY4, as measured by HPLC, decreased gradually to 1.09, 1.00, and 0.96 g/L upon increasing the storage time; however, this reduction was not significant (p > 0.05). In sensory evaluations, OLY1 gave the highest score among the experimental groups. The results of this study thereby demonstrate that olive leaf hot water extract can be used to improve the antioxidant capacity and sensory characteristics of yogurt.

Commercial yogurts as inoculum in yogurt making and their reusability properties

In Turkey, the habit of making their own yogurt in people's homes is quite common. Some of these people stated that when they used commercial yogurt as inoculum during the yogurt making, they could not achieve the product with desired properties. This research aims to investigate the possibility of using the commercial yogurts as an inoculum source in yogurt manufacturing. For this purpose, four different yogurts were produced by using four different commercial yogurts as a first inoculum separately. The yogurt production was repeated four times by using the last yogurts obtained as an inoculum. The effect of 4‒generation yogurt production on some quality characteristics of yogurt was investigated. Moreover, first fermented yogurts were analyzed throughout 21‒day storage. Titratable acidity, pH, serum separation, viscosity, and Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus counts were analyzed. The technological parameters in four yogurt generations did not show a significant change. In this context, it was concluded that the use of commercial yogurts as the first inoculum did not adversely affect the subsequent fermentation process when the necessary hygienic and temperature conditions were maintained.

참당귀잎 추출물을 첨가한 요구르트의 품질 특성

참당귀잎 추출물을 첨가한 요구르트의 품질 특성

Plant proteins supplementation effects on the quality characteristics of yogurt

Plant proteins supplementation effects on the quality characteristics of yogurt

Healthy Value and Quality Characteristics of Yoghurt as Affected by Different Concentrations of Cinnamon and Dill Ethanolic Extracts

Healthy Value and Quality Characteristics of Yoghurt as Affected by Different Concentrations of Cinnamon and Dill Ethanolic Extracts

오디분말을 첨가한 요구르트의 품질 및 항산화능에 미치는 영향

This study was conducted to investigate the effect of mulberry powder on the antioxidant activities and quality characteristics of yogurt. The samples were fermented with different amounts (0, 0.5, 1, and 3% to the yogurt quantity) of mulberry powder for 24 hr. The total phenol content, anthocyanin content, and DPPH radical scavenging activity of yogurt significantly increased with higher mulberry powder content. The pH decreased with higher mulberry powder content until 16 hr, whereas the treated groups showed higher pH levels than the control group after 20 hr. Acidities of the treated groups were higher than that of the control group upon addition of mulberry powder. Citric acid, succinic acid, and lactic acid contents of the treatment group were higher than that of the control until 16 hr, whereas the free organic acid content of the control group increased after 20 hr. The amount of lactic acid bacteria increased with higher mulberry powder content until 12 hr, whereas that of the treated group tended to decrease compared to the control group after 16 hr. Color values of mulberry yogurt were lower in terms of brightness and yellowness, whereas redness value was higher compared to the control. Mulberry yogurt groups showed higher sensory attributes than the control, except for 3% added yogurt. Consumer acceptability score of yogurt with 1% mulberry powder was ranked higher than those of other yogurts in terms of overall preference, sourness, color, flavor, and sweetness. We suggest that mulberry powder can be used to improve the quality characteristics, functionality, fermentation, and sensory evaluation of yogurt.

Effect of Colored Barley Flours on Quality Characteristics of Fermented Yogurt by Lactobacillus spp.

Quality characteristics of yogurt with added colored barely flour was investigated during fermentation by lactic acid bacteria. Chemical properties such as moisture, crude protein, starch, ash and β-glucan contents was measured. pH, acidity, brix, Hunter color value and growth of lactic acid bacteria in yogurt was investigated during fermentation by L. acidophilus, L. bulgaricus, and S. thermophilus mixed culture. Crude protein contents of Daeanchal and Boseokchal was 16.16 and 12.17%, respectively. Starch contents of daeanchal were shown lower score. The pH of yogurt by addition of barley flour (Daeanchal) addition 0 and 20% were 6.66 and 6.40, respectively. The pH of yogurt supplemented with barley flour tended to be lower than before control which was not added barely flours and oligosaccharide in yogurt. Titratable acidity of yogurt added barley flour was higher compared with that of control. Brix of yogurt was decreased during fermentation by lactic acid bacteria. Lightness of yogurt added barley flour (Daeanchal) addition 0 and 20% were 83.25 and 69.83, respectively. The original microbial population of the yogurt during 0, 5, 8, and 15 hr fermentation were 7.48, 7.79, 8.15, and 8.71 Log CFU/g, respectively. Moreover, the addition of colored barley flour was to promote the proliferation of lactic acid bacteria in yogurt. In our research, addition of colored barley flours added into the yogurt may also have contributed to growth of lactic acid bacteria.

Quality Characteristics of Yogurt Added with Sansuyu(Corni Fructus) Extracts

Quality Characteristics of Yogurt Added with Sansuyu(Corni Fructus) Extracts

Influence of Various Antioxidants on the Characteristics of Plain Yogurt

Free radical damage has been implicated in ageing and in certain degenerative conditions such as Alzheimer’s disease and other forms of dementia. Ageing is also associated with a progressive decline in the function of the immune system and an increased susceptibility to infection. Antioxidants protect the body from free radical damage. Vitamin E is the major antioxidant vitamin in body tissues and is considered the first line of defense against cell membrane damage. Other antioxidant defenses that protect the body from free radical damage include vitamin C and beta carotene. Yogurt is considered a healthy food product and its sales have been steadily increasing over the past 5 years. The objective was to study the influence of various antioxidants on the quality characteristics of yogurt. The antioxidants Vitamin C, vitamin E and beta carotene individually and in combination were incorporated at 100% of their respective recommended dietary allowance of 60 mg, 12 mg and 3 mg in 240 mL of yogurt. Yogurt manufacture and all experiments were conducted in triplicate. Use of antioxidants in yogurt manufacture significantly influenced yogurt viscosity, flavor, appearance, body texture but did not influence syneresis, lactic acid bacterial counts and pH.Depending upon the application antioxidants can be recommended in yogurt manufacture.

Quality characteristics of yogurt from goat's milk, supplemented with fruit juice

Yogurt was prepared from goat's milk, supplemented with aronia juice and blueberry juice. The dynamics of acidification, number of lactic acid bacteria, and fatty acids composition were investigated. Yogurt from goat's milk, supplemented with aronia juice and blueberry juice, coagulated at a lower acidity and faster than natural yogurt. The numbers of lactic acid bacteria in supplemented yogurts were higher compared to control samples. The addition of aronia and blueberry juices increased the amount of unsaturated fatty acids in yogurt by 6.9% and 8.5%, respectively. Polyunsaturated fatty acids increased by 11.2% in yogurt with aronia juice in comparison with natural yogurt.

Effect of Different Varieties of Date Palm Paste Incorporation on Quality Characteristics of Yoghurt

Effect of Different Varieties of Date Palm Paste Incorporation on Quality Characteristics of Yoghurt

버찌(Fruit of Prunus serrulata L. var. spontanea Max. wils.) 분말을 첨가한 요구르트의 저장 중 품질 특성

버찌분말을 첨가한 요구르트(0.0, 0.5, 1.0, 2.0%)를 제조하여 4℃에 저장하면서 14일간 품질특성을 조사하였다. 요구르트의 pH는 버찌분말 첨가에 따라 유의적으로 감소하였으며, 저장기간의 경과에 따라서는 대조구 및 버찌분말 첨가구 모두에서 낮아지는 경향을 나타내었다. 적정산도는 대조구에 비해 버찌분말 첨가 요구르트에서 높은 값을 나타내었으며, 대조구 및 버찌분말 첨가구 모두 저장기간의 경과에 따라서 산도가 증가하는 것으로 나타나 pH 변화와 비슷한 양상을 나타내었다. 버찌분말 첨가에 따라 요구르트의 당도는 높아졌으며, 점도는 감소하는 경향을 나타내었다. 요구르트의 색도는 버찌분말 첨가량이 증가할수록 명도와 황색도가 감소하고 적색도는 증가하는 유의적인 차이를 나타내었다. 항산화활성은 버찌분말의 첨가에 의해 유의적으로 증가하였다. 버찌분말 요구르트의 유산균수는 대체적으로 대조구에 비해 버찌분말 첨가 요구르트에서 높게 측정되었고 저장기간 동안 모든 시료구에서 증가하는 경향을 나타내었다. 관능평가 결과 색에 대한 선호도를 제외하고 냄새, 점성, 맛, 전반적인 기호도에서 1.0% 버찌분말 첨가구에서 높은 선호도를 나타내었다. 따라서 요구르트에 대한 버찌분말의 첨가는 저장동안의 품질 및 관능 특성, 기능성을 고려했을 경우 1.0% 첨가가 최적일 것으로 판단되었다.