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Miao M, Li S, Yang S, Yan Q, Xiang Z, Jiang Z. Engineering the β-galactosidase from Aspergillus oryzae for making lactose-free and no-sugar-added yogurt. J Dairy Sci 2024:S0022-0302(24)00769-0. [PMID: 38670341 DOI: 10.3168/jds.2023-24310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Accepted: 03/18/2024] [Indexed: 04/28/2024]
Abstract
Yogurt usually contains 5-7% sugar and 3-5% lactose. As β-galactosidases can hydrolyze lactose and improve sweetness, they have the potential to produce lactose-free (LF) and no-sugar-added (NSA) yogurt. In this study, β-galactosidase AoBgal35A from Aspergillus oryzae was engineered by site-saturation mutagenesis. Results of 19 variants of T955 residue showed that lactose hydrolysis rate of T955R-AoBgal35A was up to 90.7%, much higher than 78.5% of the wild type. Moreover, the optimal pH of T955R-AoBgal35A was shifted from pH 4.5 to pH 5.5 and the optimal temperature decreased from 60°C to 50°C. The mutant T955R-AoBgal35A was successfully expressed in Komagatella pastoris, which produced extracellularly 4528 U/mL of β-galactosidase activity. The mutant T955R-AoBgal35A was used to produce LF yogurt. Streptococcus thermophilus counts of LF yogurt increased from 7.9 to 9.5 lg cfu/g, significantly higher than that of the control group (8.9 lg cfu/g). Residual lactose content of LF yogurt was 0.13%, meeting the requirement of "lactose-free" label (<0.5%, GB 28050-2011, China). Furthermore, sugar in yogurt was replaced by whey powder to produce LF-NSA yogurt. The optimal addition content of whey powder was 7.5%. The texture, WHC and titratable acidity of LF and LF-NSA yogurt achieved good stability during the shelf life. Therefore, this study provides an insight for technological implications of β-galactosidases in the dairy industry.
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Affiliation(s)
- Miao Miao
- Key Laboratory of China National Light Industry and Food Bioengineering, College of Food Science and Nutritional Engineering, China Agricultural University, No.17 Qinghua East Road, Haidian District, Beijing 100083, China
| | - Shusen Li
- Key Laboratory of China National Light Industry and Food Bioengineering, College of Food Science and Nutritional Engineering, China Agricultural University, No.17 Qinghua East Road, Haidian District, Beijing 100083, China; Mengniu Hi-tech Dairy Product Beijing Co., Ltd., Beijing 101100, China
| | - Shaoqing Yang
- Key Laboratory of China National Light Industry and Food Bioengineering, College of Food Science and Nutritional Engineering, China Agricultural University, No.17 Qinghua East Road, Haidian District, Beijing 100083, China
| | - Qiaojuan Yan
- College of Engineering, China Agricultural University, No.17 Qinghua East Road, Haidian District, Beijing 100083, China
| | - Zhixuan Xiang
- Key Laboratory of China National Light Industry and Food Bioengineering, College of Food Science and Nutritional Engineering, China Agricultural University, No.17 Qinghua East Road, Haidian District, Beijing 100083, China
| | - Zhengqiang Jiang
- Key Laboratory of China National Light Industry and Food Bioengineering, College of Food Science and Nutritional Engineering, China Agricultural University, No.17 Qinghua East Road, Haidian District, Beijing 100083, China; Food Laboratory of Zhongyuan, Luohe 462300, China.
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2
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Li A, Zheng J, Han X, Yang S, Cheng S, Zhao J, Zhou W, Lu Y. Advances in Low-Lactose/Lactose-Free Dairy Products and Their Production. Foods 2023; 12:2553. [PMID: 37444291 PMCID: PMC10340681 DOI: 10.3390/foods12132553] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 06/21/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
With increasing health awareness worldwide, lactose intolerance has become a major concern of consumers, creating new market opportunities for low-lactose/lactose-free dairy foods. In recent years, through innovating processes and technologies, dairy manufacturers have significantly improved the variety, and functional and sensory qualities of low-lactose and lactose-free dairy products. Based on this, this paper first covers the pathology and epidemiology of lactose intolerance and market trends. Then, we focus on current advantages and disadvantages of different lactose hydrolysis technologies and improvements in these technologies to enhance nutritional value, and functional, sensory, and quality properties of lactose-free dairy products. We found that more and more cutting-edge technologies are being applied to the production of lactose-free dairy products, and that these technologies greatly improve the quality and production efficiency of lactose-free dairy products. Hopefully, our review can provide a theoretical basis for the marketing expansion and consumption guidance for low-lactose/lactose-free dairy products.
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Affiliation(s)
- Aili Li
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, 600 Changjiang Road, Harbin 150030, China; (A.L.); (J.Z.); (X.H.); (S.Y.); (S.C.); (J.Z.); (W.Z.)
| | - Jie Zheng
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, 600 Changjiang Road, Harbin 150030, China; (A.L.); (J.Z.); (X.H.); (S.Y.); (S.C.); (J.Z.); (W.Z.)
| | - Xueting Han
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, 600 Changjiang Road, Harbin 150030, China; (A.L.); (J.Z.); (X.H.); (S.Y.); (S.C.); (J.Z.); (W.Z.)
| | - Sijia Yang
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, 600 Changjiang Road, Harbin 150030, China; (A.L.); (J.Z.); (X.H.); (S.Y.); (S.C.); (J.Z.); (W.Z.)
| | - Shihui Cheng
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, 600 Changjiang Road, Harbin 150030, China; (A.L.); (J.Z.); (X.H.); (S.Y.); (S.C.); (J.Z.); (W.Z.)
| | - Jingwen Zhao
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, 600 Changjiang Road, Harbin 150030, China; (A.L.); (J.Z.); (X.H.); (S.Y.); (S.C.); (J.Z.); (W.Z.)
| | - Wenjia Zhou
- Key Laboratory of Dairy Science, Ministry of Education, College of Food Science, Northeast Agricultural University, 600 Changjiang Road, Harbin 150030, China; (A.L.); (J.Z.); (X.H.); (S.Y.); (S.C.); (J.Z.); (W.Z.)
| | - Yan Lu
- National Research Center of Dairy Engineering and Technology, Green Food Research Institute of Heilongjiang, Northeast Agricultural University, Harbin 150086, China
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3
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Aleman RS, Cedillos R, Page R, Olson D, Aryana K. Physico-chemical, microbiological, and sensory characteristics of yogurt as affected by various ingredients. J Dairy Sci 2023; 106:3868-3883. [PMID: 37080788 DOI: 10.3168/jds.2022-22622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 12/20/2022] [Indexed: 04/22/2023]
Abstract
l-Glutamine, quercetin, slippery elm bark, marshmallow root, N-acetyl-d-glucosamine, licorice root, maitake mushrooms, and zinc orotate have been reported to help treat leaky gut. The purpose of this research was to explore the impact of these functional ingredients on the physico-chemical, microbiological, and sensory properties of yogurt. The milk from same source was equally divided into 9 pails and the 8 ingredients were randomly assigned to the 8 pails. The control had no ingredient. Milk was fermented to yogurt. The pH, titratable acidity, syneresis, viscosity, color (L*, a*, b*, C*, and h*), Streptococcus thermophilus counts, and Lactobacillus delbrueckii spp. bulgaricus counts of yogurts were determined on d 1, 7, 14, 21, 28, 35, and 42, whereas coliform counts, yeast and mold counts, and rheological characteristics were determined on d 1 and 42. The sensory study was performed on d 3 and particle size of the functional ingredients (powder form) was also determined. When compared with control, the incorporation of slippery elm bark into yogurts led to less syneresis. l-Glutamine increased pH and n' values (relaxation exponent derived from G') and lowered titratable acidity values. N-Acetyl-d-glucosamine incorporation resulted in higher n' and lower titratable acidity values, whereas maitake mushroom led to lower n' values. Incorporating quercetin increased the growth of L. bulgaricus. Adding maitake mushrooms increased the growth of S. thermophilus but lowered apparent viscosity values, whereas quercetin decreased its S. thermophilus counts. Quercetin decreased L* and a* values but increased b* values, and maitake mushroom increased a* values. Thixotropic behavior increased with the addition of licorice root and quercetin. Adding slippery elm bark, N-acetyl-d-glucosamine, licorice root, maitake mushrooms, and zinc orotate into yogurt did not affect the sensory properties, whereas yogurts with quercetin had the lowest sensory scores. Overall, most of these ingredients did not cause major changes to yogurt properties.
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Affiliation(s)
- Ricardo S Aleman
- School of Nutrition and Food Sciences, Louisiana State University Agricultural Center, Baton Rouge 70803
| | - Roberto Cedillos
- School of Nutrition and Food Sciences, Louisiana State University Agricultural Center, Baton Rouge 70803
| | - Ryan Page
- School of Nutrition and Food Sciences, Louisiana State University Agricultural Center, Baton Rouge 70803
| | - Douglas Olson
- School of Nutrition and Food Sciences, Louisiana State University Agricultural Center, Baton Rouge 70803
| | - Kayanush Aryana
- School of Nutrition and Food Sciences, Louisiana State University Agricultural Center, Baton Rouge 70803.
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4
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Jia W, Du A, Fan Z, Shi L. Novel insight into the transformation of peptides and potential benefits in brown fermented goat milk by mesoporous magnetic dispersive solid phase extraction-based peptidomics. Food Chem 2022; 389:133110. [PMID: 35504074 DOI: 10.1016/j.foodchem.2022.133110] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 04/24/2022] [Accepted: 04/26/2022] [Indexed: 11/30/2022]
Abstract
Brown fermented goat milk as an excellent source of bioactive peptides has only been partially elucidated. Meticulously synthesized MOF@MG as magnetic sorbent for enriching endogenous peptides owned higher reproducibility and uniform distribution of peptides PI compared with ultrafiltration. Combined with UHPLC-Q-Orbitrap, fermentation for 12 h in brown goat milk with the highest overall acceptable degree through sensory evaluation was utilized to explore the transformation of peptides and health benefits, with trypsin or plasmin hydrolyzing proteins and aminopeptidase or carboxypeptidase hydrolyzing peptides to small peptides or amino acids. A total of 1317 peptides were identified by database matching (1259) and de novo sequencing (58), among 18 peptides could originate from gene-independent enzymatic formation and top 25 characteristic peptides were quantified with concentration ranging from 0.12 to 6.40 mg L-1. Bioinformatic analysis results indicated that brown fermented goat milk possesses higher health benefits because of more than 50 peptides with potential bioactivity.
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Affiliation(s)
- Wei Jia
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China; Shaanxi Research Institute of Agricultural Products Processing Technology, Xi'an 710021, China.
| | - An Du
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Zibian Fan
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Lin Shi
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China
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5
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Jiang TM, Liang Y, Liu B, Liu BY, Li X, Zhao JY, Li JT, Liu YP, Chen LJ. Changes in the intestinal microbiota of healthy adults induced by brown yogurt and relationships of bacterial taxa with specific components. Food Funct 2022; 13:5701-5714. [PMID: 35521810 DOI: 10.1039/d1fo03885k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Yogurt consumption shows a wide range of effects on the gut microbial composition, and correlation of components in yogurt with the changes of gut microbia remains largely uncharacterized. We aimed to determine the effect of brown yogurt (SSN) on the composition of the gut microbiota and to explore the effects of the major components. We performed a randomized study of 70 healthy adults to compare the effects of SSN and standard probiotic-containing yogurt (YJD) during a 28-day intervention and a 10-day follow-up period. The results showed that the SSN group showed significant increases in the butyrate-producer Akkermansia muciniphila, Ruminococcus, and Veillonella (p < 0.05), whereas the YJD group showed increases in the butyrate-producer Megasphaera, Anaerostipes, and Eubacterium. There were reductions in the potential pathogens Haemophilus parainfluenzae and Gemmiger formicilis in both groups (p < 0.05). The SSN group had more Faecalibacterium prausnitzii, Prevotella copri, Bifidobacterium and B. longum than the YJD group (p < 0.001), but fewer Bacteroides, unspecified Clostridiales and Coprococcus eutactus (p < 0.01). These differences might be at least in part explained by the higher concentrations of monosaccharide, palmitoleic acid, and glutamine synthetase adenyltransferase in the SSN product (p < 0.05), which were positively associated with F. prausnitzii (p ≤ 0.001) and B. longum (p < 0.05), and negatively associated with C. eutactus (p < 0.01). The single strain of starter culture and lower content of polyunsaturated fatty acids (PUFA) in the SSN product were also related to the different changes of gut microbia, and the taxa F. prausnitzii, Bifidobacterium and B. longum were negatively associated with starter culture and PUFA (p < 0.01). These findings suggested that SSN is rich in prebiotic components and might be beneficial for healthy adults. Furthermore, bacterial taxa with potential health benefits could be encouraged through improving the formulation and technology used to produce the dairy products.
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Affiliation(s)
- Tie Min Jiang
- South Asia Branch of National Engineering Center of Dairy Health for Maternal and Child, Guilin University of Technology, Guilin, China.
| | - Yi Liang
- South Asia Branch of National Engineering Center of Dairy Health for Maternal and Child, Guilin University of Technology, Guilin, China.
| | - Bin Liu
- National Engineering Center of Dairy Health for Maternal and Child, Beijing Sanyuan Foods Co. Ltd, Beijing, China.
| | - Bi Yuan Liu
- Department of Immunology, School of Medicine, Hunan University of Chinese Medicine, Changsha, China
| | - Xia Li
- South Asia Branch of National Engineering Center of Dairy Health for Maternal and Child, Guilin University of Technology, Guilin, China.
| | - Jun Ying Zhao
- National Engineering Center of Dairy Health for Maternal and Child, Beijing Sanyuan Foods Co. Ltd, Beijing, China.
| | - Jian Tao Li
- National Engineering Center of Dairy Health for Maternal and Child, Beijing Sanyuan Foods Co. Ltd, Beijing, China.
| | - Yan Pin Liu
- National Engineering Center of Dairy Health for Maternal and Child, Beijing Sanyuan Foods Co. Ltd, Beijing, China.
| | - Li Jun Chen
- National Engineering Center of Dairy Health for Maternal and Child, Beijing Sanyuan Foods Co. Ltd, Beijing, China.
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6
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Zhang Y, You S, Wang D, Zhao D, Zhang J, An Q, Li M, Wang C. Fermented Dendrobium officinale polysaccharides protect UVA-induced photoaging of human skin fibroblasts. Food Sci Nutr 2022; 10:1275-1288. [PMID: 35432966 PMCID: PMC9007291 DOI: 10.1002/fsn3.2763] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 12/22/2021] [Accepted: 01/16/2022] [Indexed: 12/11/2022] Open
Abstract
In this study, Fourier transform infrared spectroscopy (FT‐IR), gel permeation chromatograph‐liquid chromatography (GPC‐LC), and scanning electron microscopy (SEM) were used to analyze the molecular characteristics of fermented Dendrobium officinale polysaccharides (FDOP) by Lactobacillus delbrueckii bulgaricus. The characteristic structural peak of FDOP was more prominent, showing a smaller molecular structure, and its porous structure showed better water solubility. The protective effect of FDOP on the damage of human skin fibroblasts (HSF) caused by ultraviolet (UV) radiation was investigated by evaluating its antioxidative and antiaging indices. The results showed that the antioxidant capacity of HSF was improved, and the breakdown of collagen, elastin, and hyaluronic acid was reduced, thus providing effective protection to the skin tissue. The antioxidative property of FDOP was explored using Nf‐E2‐related factor 2‐small interfering RNA‐3 (Nrf2‐siRNA‐3) (Nrf2‐si3) and qRT‐PCR (quantitative reverse transcription polymerase chain reaction), and the antiaging property of FDOP was explored using Western Blot and qRT‐PCR. The results show that FDOP can up‐regulate signal transduction of the Nrf2/Keap1 (Kelch‐like ECH‐associated protein 1) and transforming growth factor‐β (TGF‐β)/Smads pathways to reduce antioxidative damage and antiaging effects. Therefore, this study provides a theoretical basis for FDOP as a novel functional agent that can be used in the cosmetic industry.
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Affiliation(s)
- Yongtao Zhang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business University Beijing China.,Chemistry and Materials Engineering Beijing Technology & Business University Beijing China.,Institute of Cosmetic Regulatory Science Beijing Technology and Business University Beijing China
| | - Shiquan You
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business University Beijing China.,Chemistry and Materials Engineering Beijing Technology & Business University Beijing China.,Institute of Cosmetic Regulatory Science Beijing Technology and Business University Beijing China
| | - Dongdong Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business University Beijing China.,Chemistry and Materials Engineering Beijing Technology & Business University Beijing China.,Institute of Cosmetic Regulatory Science Beijing Technology and Business University Beijing China
| | - Dan Zhao
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business University Beijing China.,Chemistry and Materials Engineering Beijing Technology & Business University Beijing China.,Institute of Cosmetic Regulatory Science Beijing Technology and Business University Beijing China
| | - Jiachan Zhang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business University Beijing China.,Chemistry and Materials Engineering Beijing Technology & Business University Beijing China.,Institute of Cosmetic Regulatory Science Beijing Technology and Business University Beijing China
| | - Quan An
- Yunnan Baiyao Group Co., Ltd. Kunming China
| | - Meng Li
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business University Beijing China.,Chemistry and Materials Engineering Beijing Technology & Business University Beijing China.,Institute of Cosmetic Regulatory Science Beijing Technology and Business University Beijing China
| | - Changtao Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Technology and Business University Beijing China.,Chemistry and Materials Engineering Beijing Technology & Business University Beijing China.,Institute of Cosmetic Regulatory Science Beijing Technology and Business University Beijing China
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7
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Zhao JC, Mu YL, Gu XY, Xu XN, Guo TT, Kong J. Site-directed mutation of β-galactosidase from Streptococcus thermophilus for galactooligosaccharide-enriched yogurt making. J Dairy Sci 2021; 105:940-949. [PMID: 34955252 DOI: 10.3168/jds.2021-20905] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 11/01/2021] [Indexed: 11/19/2022]
Abstract
β-Galactosidase is one of the most important enzymes used in dairy processing. It converts lactose into glucose and galactose, and also catalyzes galactose to form galactooligosaccharides (GOS), so-called prebiotics. However, most of the β-galactosidases from the starter cultures have low transgalactosylation activities, the process that results in galactose accumulation in yogurt. Here, a site-directed mutation strategy was attempted, to genetically modify β-galactosidase from Streptococcus thermophilus. Out of 28 Strep. thermophilus strains, a β-galactosidase gene named bgaQ, encoded for high β-galactosidase hydrolysis activity (BgaQ), was cloned from the strain Strep. thermophilus SDMCC050237. It was 3,081 bp in size, with 1,027 deduced amino acid residuals, which belonged to the GH2 family. After replacing the Tyr801 and Pro802 around the active sites of BgaQ with His801 and Gly802, the GOS synthesis of the generated mutant protein BgaQ-8012 increased from 20.5% to 26.7% at 5% lactose, and no hydrolysis activity altered obviously. Subsequently, the purified BgaQ or BgaQ-8012 was added to sterilized milk inoculated with 2 starters from Strep. thermophilus SDMCC050237 and Lactobacillus delbrueckii ssp. bulgaricus ATCC11842. The GOS yields with added BgaQ or BgaQ-8012 rose to 5.8 and 8.3 g/L, respectively, compared with a yield of 3.7 g/L without enzymes added. Meanwhile, the addition of the BgaQ or BgaQ-8012 reduced the lactose content by 49.3% and 54.4% in the fermented yogurt and shortened the curd time. Therefore, this study provided a site-directed mutation strategy for improvement of the transgalactosylation activity of β-galactosidase from Strep. thermophilus for GOS-enriched yogurt making.
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Affiliation(s)
- J C Zhao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China
| | - Y L Mu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China
| | - X Y Gu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China
| | - X N Xu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China
| | - T T Guo
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China
| | - J Kong
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China.
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8
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Milk Fermentation by Lacticaseibacillus rhamnosus GG and Streptococcus thermophilus SY-102: Proteolytic Profile and ACE-Inhibitory Activity. FERMENTATION-BASEL 2021. [DOI: 10.3390/fermentation7040215] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Health benefits of probiotics and production of inhibitors of angiotensin converting enzyme (ACE) released during milk fermentation are well known. That is why in this investigation the proteolytic profile and ACE inhibitory capacity of peptide fractions from protein hydrolysis of milk during fermentation processes was analyzed. Milk fermentation was carried out inoculating 106 CFU of L. rhamnosus GG, S. thermophilus SY-102 and with both bacteria. The proteolytic profile was determined using: TNBS, SDS-PAGE and SEC-HPLC techniques. In vitro ACE inhibition capacity was measured. The pH of 4.5 was reached at 56 h when the milk was fermented with L. rhamnosus, at 12 h with S. thermophillus and at 41 h in the co-culture. Production of free amino groups corresponded with the profile of low molecular weight peptides observed by SDS-PAGE and SEC-HPLC. Co-culture fermentation showed both the highest concentration of low molecular weight peptides and the ACE inhibitory activity (>80%). Results indicated that the combination of lactic cultures could be useful in manufacture of fermented milk with an added value that goes beyond basic nutrition, such as the production of ACE-inhibitory peptides.
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9
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Jia W, Liu Y, Shi L. Integrated metabolomics and lipidomics profiling reveals beneficial changes in sensory quality of brown fermented goat milk. Food Chem 2021; 364:130378. [PMID: 34153599 DOI: 10.1016/j.foodchem.2021.130378] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 06/10/2021] [Accepted: 06/12/2021] [Indexed: 10/21/2022]
Abstract
Fermentation and thermal processing can improve the sensory properties of foods. Chemical composition of fermented brown goat milk was investigated using an integrated lipomics and metabonomic method while the effects of changes in chemical composition on sensory quality were also explored. After fermentation, organic acid, peptide and medium- and long-chain fatty acid contents in brown goat milk samples increased significantly. A total of 108 metabolites and 174 lipids related to sensory quality were identified. Heterocyclic compounds, as intermediates of Maillard reaction, modified colour, taste, and aroma, while changes in triglyceride content reduced the impact of off-odour, greatly improving sensory quality of fermented brown goat milk. This study provided new approaches for examining goat milk sensory quality and insights into how these can be modified to further diversify dairy products on the market.
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Affiliation(s)
- Wei Jia
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China; Shaanxi Research Institute of Agricultural Products Processing Technology, Xi'an 710021, China.
| | - Yuyang Liu
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Lin Shi
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China.
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