1
|
Krebs L, Verhoeven J, Verbruggen S, Lesar A, Meddah R, Blouin M, Venema K, Chamberland J, Brisson G. Assessment of protein and phospholipid bioaccessibility in ultrafiltered buttermilk cheese using TIM-1 in vitro gastrointestinal methods. Food Res Int 2024; 190:114606. [PMID: 38945574 DOI: 10.1016/j.foodres.2024.114606] [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: 01/10/2024] [Revised: 06/04/2024] [Accepted: 06/04/2024] [Indexed: 07/02/2024]
Abstract
To meet the high consumer demand, butter production has increased over the last few years. As a result, the buttermilk (BM) co-produced volumes require new ways of adding value, such as in cheese manufacturing. However, BM use in cheese milk negatively influences the cheesemaking process (e.g., altered coagulation properties) and the product's final quality (e.g., high moisture content). The concentration of BM by ultrafiltration (UF) could potentially facilitate its use in cheese manufacturing through an increased protein content while maintaining the milk salt balance. Simultaneously, little is known about the digestion of UF BM cheese. Therefore, this study aimed to characterize the impact of UF BM on cheese manufacture, its structure, and its behavior during in vitro digestion. A 2-fold UF concentrated BM was used for cheese manufacture (skim milk [SM] - control). Compositional, textural, and microstructural analyses of cheeses were first conducted. In a second step, the cheeses were fed into an in vitro TNO gastrointestinal digestion model (TIM-1) of the stomach and small intestine and protein and phospholipid (PL) bioaccessibility was studied. The results showed that UF BM cheese significantly differed from SM cheese regarding its composition, hardness (p < 0.05) and microstructure. However, in TIM-1, UF BM and SM cheeses showed similar digestion behavior as a percentage of protein and PL intake. Despite relatively more non-digested and non-absorbed PL in the ileum efflux of UF BM cheese, the initially higher PL concentration contributes to an enhanced nutritional value compared to SM cheese. To our knowledge, this study is the first to compare the bioaccessibility of proteins and PL from UF BM and SM cheeses.
Collapse
Affiliation(s)
- Louise Krebs
- Institute of Nutrition and Functional Foods (INAF), Dairy Science and Technology Research Centre (STELA), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada
| | - Jessica Verhoeven
- Centre for Healthy Eating & Food Innovation (HEFI), Faculty of Science and Engineering, Maastricht University - campus Venlo, 5928 SZ Venlo, the Netherlands
| | - Sanne Verbruggen
- Centre for Healthy Eating & Food Innovation (HEFI), Faculty of Science and Engineering, Maastricht University - campus Venlo, 5928 SZ Venlo, the Netherlands
| | - Aleksander Lesar
- University of Ljubljana, Biotechnical Faculty, 1000 Ljubljana, Slovenia
| | - Rihab Meddah
- Institute of Nutrition and Functional Foods (INAF), Dairy Science and Technology Research Centre (STELA), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada
| | - Maude Blouin
- Institute of Nutrition and Functional Foods (INAF), Dairy Science and Technology Research Centre (STELA), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada
| | - Koen Venema
- Centre for Healthy Eating & Food Innovation (HEFI), Faculty of Science and Engineering, Maastricht University - campus Venlo, 5928 SZ Venlo, the Netherlands
| | - Julien Chamberland
- Institute of Nutrition and Functional Foods (INAF), Dairy Science and Technology Research Centre (STELA), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada
| | - Guillaume Brisson
- Institute of Nutrition and Functional Foods (INAF), Dairy Science and Technology Research Centre (STELA), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada.
| |
Collapse
|
2
|
Krebs L, Pouliot Y, Doyen A, Venema K, Brisson G. Effect of reverse osmosis and ultra-high-pressure homogenization on the composition and microstructure of sweet buttermilk. J Dairy Sci 2023; 106:1596-1610. [PMID: 36586799 DOI: 10.3168/jds.2022-22483] [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: 07/05/2022] [Accepted: 09/21/2022] [Indexed: 12/31/2022]
Abstract
Buttermilk (BM), the by-product of butter making, is similar to skim milk (SM) composition. However, it is currently undervalued in dairy processing because it is responsible for texture defects (e.g., crumbliness, decreased firmness) in cheese and yogurt. One possible way of improving the incorporation of BM into dairy products is by the use of technological pretreatments such as membrane filtration and homogenization. The study aimed at characterizing the effect of preconcentration by reverse osmosis (RO) and single-pass ultra-high-pressure homogenization (UHPH) on the composition and microstructure of sweet BM to modify its techno-functional properties (e.g., protein gel formation, syneresis, firmness). The BM and RO BM were treated at 0, 15, 150, and 300 MPa. Pressure-treated and control BM and RO BM were ultracentrifuged to fractionate them into the following 3 fractions: a supernatant soluble fraction (top layer), a colloidal fraction consisting of a cloudy layer (middle layer), and a high-density pellet (bottom layer). Compositional changes in the soluble fraction [lipid, phospholipid (PL), protein, and salt], as well as its protein profile by PAGE analysis, were determined. Modifications in particle size distribution upon UHPH were monitored by laser diffraction in the presence and absence of sodium citrate to dissociate the casein (CN) micelles. Microstructural changes in pressure-treated and non-pressure-treated BM and RO BM particles were monitored by confocal laser scanning microscopy. Particle size analysis showed that UHPH treatment significantly decreased the size of the milk fat globule membrane fragments in BM and RO BM. Also, pressure treatment at 300 MPa led to a significant increase in the recovery of total lipids, CN, calcium, and phosphate in the BM soluble fraction (top layer) following ultracentrifugation. However, PL were primarily concentrated in the pellet cloud (middle layer), located above the pellet in BM concentrated by RO. In contrast, PL were evenly distributed between soluble and colloidal phases of BM. This study provides insight into the modifications of sweet BM constituents induced by RO and UHPH from a compositional and structural perspective.
Collapse
Affiliation(s)
- L Krebs
- Institute of Nutrition and Functional Foods (INAF), Dairy Science and Technology Research Centre (STELA), Department of Food Sciences, Université Laval, Quebec, G1V 0A6, Canada
| | - Y Pouliot
- Institute of Nutrition and Functional Foods (INAF), Dairy Science and Technology Research Centre (STELA), Department of Food Sciences, Université Laval, Quebec, G1V 0A6, Canada
| | - A Doyen
- Institute of Nutrition and Functional Foods (INAF), Dairy Science and Technology Research Centre (STELA), Department of Food Sciences, Université Laval, Quebec, G1V 0A6, Canada
| | - K Venema
- Centre for Healthy Eating & Food Innovation (HEFI), Faculty of Science and Engineering, Maastricht University-Venlo, 5928 SZ, the Netherlands
| | - G Brisson
- Institute of Nutrition and Functional Foods (INAF), Dairy Science and Technology Research Centre (STELA), Department of Food Sciences, Université Laval, Quebec, G1V 0A6, Canada.
| |
Collapse
|
3
|
Chamberland J, Brisson G, Doyen A, Pouliot Y. Innovations from pressure-driven membrane processes in cheese technology: from milk protein concentrates to sustainability and precision cheesemaking. Curr Opin Food Sci 2022. [DOI: 10.1016/j.cofs.2022.100948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
4
|
Effect of cheese composition and cheese-making conditions on salt and moisture transfer during brining. Int Dairy J 2022. [DOI: 10.1016/j.idairyj.2022.105325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
5
|
Valorization of Concentrated Dairy White Wastewater by Reverse Osmosis in Model Cheese Production. DAIRY 2022. [DOI: 10.3390/dairy3020020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Treatment of dairy white wastewater (WW) by reverse osmosis (RO) is usually performed to generate process water and to reclaim dairy components for their valorization. For this study, a mixture of pasteurized milk and WW from a dairy plant was concentrated by RO to achieve a protein concentration similar to that of skimmed milk. Retentates, which are concentrated WW, were used in the preparation of cheese milk. The effect of using model concentrated WW was evaluated on (1) the soluble–colloidal equilibrium between protein and salt, (2) the milk-coagulation kinetics, and (3) the cheese composition and yield. An economic assessment was also carried out to support the decision-making process for implementing a new RO system in a dairy plant for the valorization of dairy WW. The results showed that substituting more than 50% of the amount of cheese milk with model pasteurized WW concentrates decreased the moisture-adjusted cheese yield and impaired the coagulation kinetics. Excessive cheese moisture was observed in cheeses that were made from 50% and 100% model WW concentrates, correlating with a change in the soluble–colloidal equilibrium of salts, especially in calcium. To achieve sustainable and economic benefits, the ratio of added WW concentrates to cheese milk must be less than 50%. However, for such an investment to be profitable to a dairy plant within 0.54 years, a large-size plant must generate 200 m3 of WW per day with at least 0.5% of total solids, as the economic analysis specific to our case suggests.
Collapse
|
6
|
Zanghaneh E, Mirzaei H, Jafari SM, Javadi A, Afshar Mogaddam MR. Spirulina platensis extract nanoliposomes: preparation, characterization and application to white cheese. J AOAC Int 2021; 105:827-834. [PMID: 34904627 DOI: 10.1093/jaoacint/qsab162] [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: 10/10/2021] [Revised: 11/16/2021] [Accepted: 12/01/2021] [Indexed: 11/12/2022]
Abstract
BACKGROUND Ultrafiltration cheese is produced in large scale from treated and pasteurized treated and pasteurized milk with mesophilic starter and to expand its shelf life preservatives addition is needed. OBJECTIVE The purpose of the present study was preparation of encapsulate Spirulina platensis algae nanoliposomes to evaluate the characteristics of the nanoliposomes loaded with Spirulina extract (SE-NLs). In addition, the chemical and microbiological properties of white cheese produced with SE-NLs were studied. METHODS Nanoliposomes are composed of lecithin and cholesterol, used for the encapsulation of SE. The SE-NLs were prepared using the thin layer hydration method. The characteristics of produced SE-NLs including particle size, zeta potential, morphology and the encapsulation efficiency (EE) was studied during 4 weeks in different storage conditions (4 °C and 25 °C). In addition, the effect of SE and SE-NLs on the chemical and microbiological properties of white cheese was evaluated during 60 days of ripening. RESULTS The results showed that the nanoliposomes loaded with 3 mg/g of SE had the optimum formulation due to the higher EE, smaller particle size, and higher negatively charged zeta potential. The quality of the produced nanoliposomes decreased by increasing the time of storage but the SE-NLs stored at 4 °C were more stable and possessed higher EE and smaller particle sizes. While the chemical composition of the cheeses manufactured by the nanoliposome loaded with 3 mg/g SE- NLs were comparable to that of control cheese at 60 days of ripening, it showed a significant inhibitory effect on Staphylococcus aureus and Listeria monocytogenes after 30 days. CONCLUSION The utilization of SE-NLs can be considered as a natural antimicrobial and an alternative to the use of synthetic preservatives in the production of white cheese. HIGHLIGHTS Nanoliposomes of Spirulina platensis extracts was prepared.UF white cheese prepared by nanoliposomes and then were evaluated.
Collapse
Affiliation(s)
- Esmaiel Zanghaneh
- Department of Food hygiene, Tabriz Branch, Islamic Azad University, Tabriz, Iran
| | - Hamid Mirzaei
- Department of Food hygiene, Tabriz Branch, Islamic Azad University, Tabriz, Iran
| | - Seid Mahdi Jafari
- Department of Clinical Biochemistry, School of medicine, Golestan University of Medical Sciences, Golestan
| | - Afshin Javadi
- Department of Food hygiene, Tabriz Branch, Islamic Azad University, Tabriz, Iran
| | - Mohammad Reza Afshar Mogaddam
- Food and Drug Safety Research Center, Tabriz University of Medical Science, Tabriz, Iran.,Pharmaceutical Analysis Research Center, Tabriz University of Medical Science, Tabriz, Iran
| |
Collapse
|
7
|
Reig M, Vecino X, Cortina JL. Use of Membrane Technologies in Dairy Industry: An Overview. Foods 2021; 10:foods10112768. [PMID: 34829049 PMCID: PMC8620702 DOI: 10.3390/foods10112768] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 10/26/2021] [Accepted: 11/08/2021] [Indexed: 01/11/2023] Open
Abstract
The use of treatments of segregated process streams as a water source, as well as technical fluid reuse as a source of value-added recovery products, is an emerging direction of resource recovery in several applications. Apart from the desired final product obtained in agro-food industries, one of the challenges is the recovery or separation of intermediate and/or secondary metabolites with high-added-value compounds (e.g., whey protein). In this way, processes based on membranes, such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO), could be integrated to treat these agro-industrial streams, such as milk and cheese whey. Therefore, the industrial application of membrane technologies in some processing stages could be a solution, replacing traditional processes or adding them into existing treatments. Therefore, greater efficiency, yield enhancement, energy or capital expenditure reduction or even an increase in sustainability by producing less waste, as well as by-product recovery and valorization opportunities, could be possible, in line with industrial symbiosis and circular economy principles. The maturity of membrane technologies in the dairy industry was analyzed for the possible integration options of membrane processes in their filtration treatment. The reported studies and developments showed a wide window of possible applications for membrane technologies in dairy industry treatments. Therefore, the integration of membrane processes into traditional processing schemes is presented in this work. Overall, it could be highlighted that membrane providers and agro-industries will continue with a gradual implementation of membrane technology integration in the production processes, referring to the progress reported on both the scientific literature and industrial solutions commercialized.
Collapse
Affiliation(s)
- Mònica Reig
- Barcelona Research Center for Multiscale Science and Engineering, Campus Diagonal-Besòs, 08930 Barcelona, Spain; (X.V.); (J.L.C.)
- Chemical Engineering Department, Escola d’Enginyeria de Barcelona Est (EEBE), Campus Diagonal-Besòs, Universitat Politècnica de Catalunya (UPC)-BarcelonaTECH, C/Eduard Maristany 10-14, 08930 Barcelona, Spain
- Correspondence: ; Tel.: +34-93-4016184
| | - Xanel Vecino
- Barcelona Research Center for Multiscale Science and Engineering, Campus Diagonal-Besòs, 08930 Barcelona, Spain; (X.V.); (J.L.C.)
- Chemical Engineering Department, Escola d’Enginyeria de Barcelona Est (EEBE), Campus Diagonal-Besòs, Universitat Politècnica de Catalunya (UPC)-BarcelonaTECH, C/Eduard Maristany 10-14, 08930 Barcelona, Spain
| | - José Luis Cortina
- Barcelona Research Center for Multiscale Science and Engineering, Campus Diagonal-Besòs, 08930 Barcelona, Spain; (X.V.); (J.L.C.)
- Chemical Engineering Department, Escola d’Enginyeria de Barcelona Est (EEBE), Campus Diagonal-Besòs, Universitat Politècnica de Catalunya (UPC)-BarcelonaTECH, C/Eduard Maristany 10-14, 08930 Barcelona, Spain
- CETaqua, Carretera d’Esplugues, 75, 08940 Cornellà de Llobregat, Spain
| |
Collapse
|
8
|
Deshwal GK, Ameta R, Sharma H, Singh AK, Panjagari NR, Baria B. Effect of ultrafiltration and fat content on chemical, functional, textural and sensory characteristics of goat milk-based Halloumi type cheese. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2020.109341] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
9
|
Fournier I, Britten M, Pouliot Y. Drainage and demineralisation of model cheeses made from reverse osmosis concentrates. Int Dairy J 2020. [DOI: 10.1016/j.idairyj.2019.104628] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
10
|
Lauzin A, Pouliot Y, Britten M. Understanding the differences in cheese-making properties between reverse osmosis and ultrafiltration concentrates. J Dairy Sci 2019; 103:201-209. [PMID: 31677839 DOI: 10.3168/jds.2019-16542] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 09/08/2019] [Indexed: 11/19/2022]
Abstract
Concentrating milk by reverse osmosis (RO) has the potential to increase cheese yield but is known to impair cheese-making properties. The main compositional differences between ultrafiltration (UF) and RO concentrates are the high lactose and mineral contents of the latter. The objective of this work was to determine the distinct effects of high lactose and high minerals on the cheese-making properties of RO concentrate, by supplementing UF concentrate with lactose. The soluble colloidal equilibria of concentrates were studied as well as several other properties: rennet gelation behavior, cheese mass balance, composition, and microstructure. Rennet coagulation time was longer and gel firming rate was lower for RO concentrate than for UF concentrate. Lactose was mainly responsible for these differences. Lactose in RO concentrate was also responsible for the 7% increase of moisture-adjusted cheese yield, relative to UF concentrate. Compared with cheese made from UF concentrate, cheese made from RO concentrate showed higher moisture content, which could not be attributed to lactose but to the high mineral concentration. This study showed the potential of using RO instead of UF concentrate to maximize cheese yield. The approach is, however, limited to applications where post-acidification can be controlled, and will require appropriate strategies to reduce the negative effects of high mineral content in RO concentrate.
Collapse
Affiliation(s)
- A Lauzin
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Science, Université Laval, Québec, Canada, G1V 0A6
| | - Y Pouliot
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Science, Université Laval, Québec, Canada, G1V 0A6.
| | - M Britten
- Saint-Hyacinthe Food Research Center (SHFRC), Agriculture and Agri-Food Canada, J2S 8E3
| |
Collapse
|
11
|
Dussault-Chouinard I, Britten M, Pouliot Y. Improving rennet coagulation and cheesemaking properties of reverse osmosis skim milk concentrates by pH adjustment. Int Dairy J 2019. [DOI: 10.1016/j.idairyj.2019.03.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
12
|
Chamberland J, Mercier-Bouchard D, Dussault-Chouinard I, Benoit S, Doyen A, Britten M, Pouliot Y. On the Use of Ultrafiltration or Microfiltration Polymeric Spiral-Wound Membranes for Cheesemilk Standardization: Impact on Process Efficiency. Foods 2019; 8:foods8060198. [PMID: 31181741 PMCID: PMC6617294 DOI: 10.3390/foods8060198] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/04/2019] [Accepted: 06/06/2019] [Indexed: 12/03/2022] Open
Abstract
Ultrafiltration (UF) and microfiltration (MF) are widely-used technologies to standardize the protein content of cheesemilk. Our previous work demonstrated that protein retention of a 0.1-µm MF spiral-wound membrane (SWM) was lower, but close to that of a 10 kDa UF one. Considering that the permeability of MF membranes is expected to be higher than that of UF ones, it was hypothesized that the former could improve the efficiency of the cheesemaking process. Consequently, the objectives of this work were to compare 0.1-µm MF and 10 kDa UF spiral-wound membranes in terms of (1) hydraulic and separation performance, (2) energy consumption and fouling behavior, (3) cheesemaking efficiency of retentates enriched with cream, and (4) economic performance in virtual cheesemaking plants. This study confirmed the benefits of using MF spiral-wound membranes to reduce the specific energy consumption of the filtration process (lower hydraulic resistance and higher membrane permeability) and to enhance the technological performance of the cheesemaking process (higher vat yield, and protein and fat recoveries). However, considering the higher serum protein retention of the UF membrane and the low price of electricity in Canada, the UF scenario remained more profitable. It only becomes more efficient to substitute the 10 kDa UF SWM by the 0.1-μm MF when energy costs are substantially higher.
Collapse
Affiliation(s)
- Julien Chamberland
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada.
| | - Dany Mercier-Bouchard
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada.
| | - Iris Dussault-Chouinard
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada.
| | - Scott Benoit
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada.
| | - Alain Doyen
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada.
| | - Michel Britten
- Food Research and Development Center (FRDC), Agriculture and Agri-Food Canada, Saint-Hyacinthe, QC J2S 8E3, Canada.
| | - Yves Pouliot
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Sciences, Université Laval, Québec, QC G1V 0A6, Canada.
| |
Collapse
|
13
|
Lauzin A, Bérubé A, Britten M, Pouliot Y. Effect of pH adjustment on the composition and rennet-gelation properties of milk concentrates made from ultrafiltration and reverse osmosis. J Dairy Sci 2019; 102:3939-3946. [PMID: 30852024 DOI: 10.3168/jds.2018-15902] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 01/14/2019] [Indexed: 11/19/2022]
Abstract
The objective of this work was to investigate the effect of pH adjustment (initial pH vs. pH 6.50) on the rennet-gelation properties of concentrates made by ultrafiltration (UF) and reverse osmosis (RO). Rennet-gelation kinetics were followed by dynamic rheology and κ-casein hydrolysis by reverse-phase HPLC. At initial pH, RO concentrates had better rennet-coagulation behavior than UF concentrates and skim milk, whereas adjusting the pH to 6.50 produced the opposite results. The kinetics of κ-casein hydrolysis were similar in skim milk, and both concentrates and were not affected by pH adjustment. Differences in rennet coagulation were then related to the extent of hydrolysis required to trigger casein micelle aggregation. Small pH adjustments (<0.2 pH unit) enabled the use of RO concentrate with similar rennet-gelation behavior to UF concentrate, despite major compositional differences. This study shows that pH adjustment of RO concentrates can be a simple approach to improve their coagulation properties; however, the mechanisms behind these improvements remain to be elucidated.
Collapse
Affiliation(s)
- A Lauzin
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Science, Université Laval, Québec, Canada G1V 0A6
| | - A Bérubé
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Science, Université Laval, Québec, Canada G1V 0A6
| | - M Britten
- St-Hyacinthe Food Research Center (SHFRC), Agriculture and Agri-Food Canada, St-Hyacinthe, Canada J2S 8E3
| | - Y Pouliot
- STELA Dairy Research Center, Institute of Nutrition and Functional Foods (INAF), Department of Food Science, Université Laval, Québec, Canada G1V 0A6.
| |
Collapse
|