Dairy Research Bulletin Selected Articles from November 2023

Environmental Management and Sustainability

Methane Emissions from Dairy Operations in California’s San Joaquin Valley Evaluated Using Airborne Flux Measurements. Schulze BC, Seinfeld JH, et al. Environ Sci Technol. 2023 Nov 24.

  • State inventories indicate that dairy operations account for nearly half of California’s methane budget. Recent analyses suggest, however, that these emissions may be underestimated, complicating efforts to develop emission reduction strategies.
  • Here, researchers report estimates of dairy methane emissions in the southern San Joaquin Valley (SJV) of California in June 2021 using airborne flux measurements.
  • The study found average dairy methane fluxes of 512 ± 178 mg m-2 h-1 from a region of 300+ dairies near Visalia, CA using a combination of eddy covariance and mass balance-based techniques, corresponding to 118 ± 41 kg dairy-1 h-1. These values estimated during the June campaign are 39 ± 48% larger than annual average estimates from the recently developed VISTA-CA inventory.
  • The researchers observed notable increases in emissions with temperature. These estimates align well with inventory predictions when parametrizations for the temperature dependence of emissions are applied. The measurements further demonstrate that the VISTA-CA emission inventory is considerably more accurate than the EPA GHG-I inventory in this region.
  • Source apportionment analyses confirm that dairy operations produce the majority of methane emissions in the southern SJV (∼65%). Fugitive oil and gas (O&G) sources account for the remaining ∼35%.
  • These results support the accuracy of the process-based models used to develop dairy emission inventories and highlight the need for additional investigation of the meteorological dependence of these emissions.

From waste to wealth: Innovations in organic solid waste composting. Xu M, Sun H, Chen E, Yang M, Wu C, Sun X, Wang Q. Environ Res. 2023;229:115977.

  • Organic solid waste (OSW) is not only a major source of environmental contamination, but also a vast store of useful materials due to its high concentration of biodegradable components that can be recycled.
  • Composting has been proposed as an effective strategy for recycling OSW back into the soil in light of the necessity of a sustainable and circular economy. In addition, unconventional composting methods such as membrane-covered aerobic composting and vermicomposting have been reported more effective than traditional composting in improving soil biodiversity and promoting plant growth.
  • This review investigates the current advancements and potential trends of using widely available OSW to produce fertilizers. At the same time, this review highlights the crucial role of additives such as microbial agents and biochar in the control of harmful substances in composting.
  • Composting of OSW should include a complete strategy and a methodical way of thinking that can allow product development and decision optimization through interdisciplinary integration and data-driven methodologies.
  • Future research will likely concentrate on the potential in controlling emerging pollutants, evolution of microbial communities, biochemical composition conversion, and the micro properties of different gases and membranes.
  • Additionally, screening of functional bacteria with stable performance and exploration of advanced analytical methods for compost products are important for understanding the intrinsic mechanisms of pollutant degradation.

Synergistic effects of earthworms and cow manure under reduced chemical fertilization modified microbial community structure to mitigate continuous cropping effects on Chinese flowering cabbage. Gao F, Ye L, Mu X, Xu L, Shi Z, Luo Y. Front Microbiol. 2023 Oct 26;14:1285464.

  • The substitution of chemical fertilizers with organic fertilizers is a viable strategy to enhance crop yield and soil quality.
  • In this study, the aim was to investigate the changes in soil microorganisms, soil chemical properties, and growth of Chinese flowering cabbage under different fertilization treatments involving earthworms and cow manure.
  • Compared with the control (100% chemical fertilizer), CE (30% reduction in chemical fertilizer + earthworms) and CFE (30% reduction in chemical fertilizer + cow dung + earthworms) treatments at soil pH 8.14 and 8.07, respectively, and CFC (30% reduction in chemical fertilizer + cow manure) and CFE treatments increased soil organic matter (SOM), total nitrogen (TN), available nitrogen (AN), and available potassium (AK) contents.
  • Earthworms and cow manure promoted the abundance of Bacillus and reduced that of the pathogens Plectosphaerella and Gibberella. The mantle test revealed that pH was not correlated with the microbial community. Random forest analysis verified that AN, SOM, and TN were important factors that jointly influenced bacterial and fungal diversity.
  • Overall, the synergistic effect of earthworms and cow manure increased soil fertility and microbial diversity, thereby promoting the growth and development of Chinese flowering cabbage.

Towards sustainability: An integrated life cycle environmental-economic insight into cow manure management. Zhang T, Bai Y, Zhou X, Li Z, Cheng Z, Hong J. Waste Manag. 2023 Dec 1;172:256-266.

  • Waste management signifies an equilibrium between environmental and economic factors. However, a comprehensive understanding of the integrated life cycle environmental-economic performance of waste management activities remains unclear.
  • To facilitate a systematic linkage between the economic and environmental sectors, a regionalized life cycle assessment-based life cycle costing method was developed based on China’s actual status quo. The cow manure utilization was set as an entry point to explored long-term environmental-economic performance of milk production under various manure utilization pathways.
  • The results show that trade-offs were observed between internal and external costs as well as various environmental indicators. The choice of waste utilization is the focal point of environmental-economic trade-offs in the cow raising system.
  • The optimal environmental-economic performance was achieved through the manure fertilizer utilization pathway, yielding a remarkable three-fold increase in marginal environmental benefits.
  • Compared with fertilizer utilization, the manure direct returning to field reduced the carbon footprint by 12% while induced an external cost of $14.3. The wastewater treatment pathway is $ 5.5 lower in internal costs but $ 11.7 higher in external costs than those of fertilizer utilization.
  • Overall, utilizing manure has potential to mitigate the upward trend of carbon footprint and external costs. However, achieving the carbon peak remains a significant challenge. A promising solution is the recycling of straw resources within cropping systems, particularly in hotspot regions (e.g., Inner Mongolia, Heilongjiang, Hebei, and Shandong).
  • A comprehensive analysis of the dynamic interplay between cropping systems and cow raising systems is critical steps towards realizing a carbon-neutral future within the dairy production.

Could natural phytochemicals be used to reduce nitrogen excretion and excreta-derived N2O emissions from ruminants? Zhao Y, Liu M, Jiang L, Guan L. J Anim Sci Biotechnol. 2023 Nov 9;14(1):140.

  • Ruminants play a critical role in our food system by converting plant biomass that humans cannot or choose not to consume into edible high-quality food. However, ruminant excreta is a significant source of nitrous oxide (N2O), a potent greenhouse gas with a long-term global warming potential 298 times that of carbon dioxide.
  • Natural phytochemicals or forages containing phytochemicals have shown the potential to improve the efficiency of nitrogen (N) utilization and decrease N2O emissions from the excreta of ruminants.
  • Dietary inclusion of tannins can shift more of the excreted N to the feces, alter the urinary N composition and consequently reduce N2O emissions from excreta. Essential oils or saponins could inhibit rumen ammonia production and decrease urinary N excretion.
  • In grazed pastures, large amounts of glucosinolates or aucubin can be introduced into pasture soils when animals consume plants rich in these compounds and then excrete them or their metabolites in the urine or feces. If inhibitory compounds are excreted in the urine, they would be directly applied to the urine patch to reduce nitrification and subsequent N2O emissions.
  • The phytochemicals’ role in sustainable ruminant production is undeniable, but much uncertainty remains. Inconsistency, transient effects, and adverse effects limit the effectiveness of these phytochemicals for reducing N losses.
  • In this review, researchers identify some current phytochemicals found in feed that have the potential to manipulate ruminant N excretion or mitigate N2O production and deliberate the challenges and opportunities associated with using phytochemicals or forages rich in phytochemicals as dietary strategies for reducing N excretion and excreta-derived N2O emissions.
Animal Health and Food Safety

Academics meet practitioners: Interactive exchange instead of consuming knowledge  on dairy calving management. Mee JF, Szenci O, Fischer-Tenhagen C. Reprod Domest Anim. 2023 Nov 16.

  • Consensus on optimal calving management is difficult to achieve among veterinarians. Some of this discordance may stem from asymmetry between the literature written by subject matter experts (SME) and the knowledge, attitude and practice (KAP) of non-SMEs and veterinary practitioners.
  • Hence, the objective of this study was to assess how veterinary practitioners KAPs in calving management compared with the findings in the literature.
  • An online questionnaire survey was conducted prior to a World Buiatrics Congress by delegates (n = 80) who attended a workshop on calving management at which the outcomes of the latter were recorded. The responses from the questionnaire and the consensus from the workshop were compared and these were compared with the literature on calving management, specifically, prediction of calving, assistance at calving and farmer training in calving management.
  • In general, there was good agreement between the aggregated individual responses to the questionnaire and the consensuses from the workshop. The suggested methods of predicting calving were well aligned between practitioners and those researched in the literature but practitioners tended to emphasize more practical aspects of prediction while the literature tends to focus more on the effectiveness of various predictor devices.
  • Practitioners tended to recommend a later time of calving assistance than that recommended in the recent literature though they did also emphasize the importance of calving progress. The majority of practitioners conducted informal (at calving) calving training focusing on time of intervention, welfare-friendly intervention and delivery of a live healthy calf. However, the educational literature recommends a formal training approach as being more effective.
  • These findings indicate that practitioners may benefit from continuing professional education on the scientific merits/demerits of calving prediction devices, current best practice on intervention timing during calving and formal methods of farmer training on calving management.

Comparative Analysis of Rumen Microbiota Composition in Dairy Cows with Simple Indigestion and Healthy Cows. Wang S, Kong F, Liu J, Xia J, Du W, Li S, Wang W. Microorganisms. 2023 Oct 31;11(11):2673.

  • Simple indigestion in cows leads to substantial economic losses in the dairy industry. Despite ongoing efforts, an effective treatment for this issue remains elusive. Previous studies have emphasized the vital role of rumen microbes in maintaining ruminant health.
  • To deepen the comprehension of the intricate interplay between rumen microbiota and simple indigestion, researchers undertook a study involving the analysis of rumen fluid from eight cows with simple indigestion and ten healthy cows. Additionally, the researchers collected data pertaining to milk production, rumination behavior, and rumen characteristics.
  • The results showed that cows with simple indigestion displayed significantly lower milk yield, reduced rumination duration, and weakened rumen contraction when contrasted with the healthy cows. However, no significant difference in microbiota α-diversity emerged. Principal coordinate analysis (PCoA) illuminated substantial variations in rumen microbial structure among the two groups.
  • Further analysis spotlighted distinctive bacteria in the rumen of the cows with indigestion, including Allisonella, Synergistes, Megasphaera, Clostridium_XIVb, Campylobacter, and Acidaminococcus. In contrast, Coraliomargarita, Syntrophococcus, and Coprococcus are the dominant bacterial genera in the rumen of healthy dairy cows.
  • Importantly, these key bacterial genera also dominated the overarching microbial interaction network. The observation suggests that changes in the abundance of these dominant bacterial genera potentially underlie the principal etiology of cows with simple indigestion. The present findings can provide insights into simple indigestion prevention and treatment in dairy cows.

Persistent effects of intramammary ceftiofur treatment on the gut microbiome and antibiotic resistance in dairy cattle. Vasco KA, Carbonell S, Manning SD, et al. Anim Microbiome. 2023 Nov 9;5(1):56.

  • Intramammary (IMM) ceftiofur treatment is commonly used in dairy farms to prevent mastitis, though its impact on the cattle gut microbiome and selection of antibiotic-resistant bacteria has not been elucidated.
  • Herein, researchers enrolled 40 dairy (Holstein) cows at the end of the lactation phase for dry-cow therapy: 20 were treated with IMM ceftiofur (Spectramast®DC) and a non-antibiotic internal teat sealant (bismuth subnitrate) and 20 (controls) received only bismuth subnitrate.
  • Overall, 90% and 24% of the 278 samples had Gram-negative bacteria with resistance to ampicillin and ceftiofur, respectively. Most of the cows treated with ceftiofur did not have an increase in the number of resistant bacteria; however, a subset (25%) shed higher levels of ceftiofur-resistant bacteria for up to 2 weeks post-treatment.
  • At week 5, the antibiotic-treated cows had lower microbiota abundance and richness, whereas a greater abundance of genes encoding extended-spectrum β-lactamases (ESBLs), CfxA, ACI-1, and CMY, was observed at weeks 1, 5 and 9.
  • Moreover, the contig and network analyses detected associations between β-lactam resistance genes and phages, mobile genetic elements, and specific genera. Commensal bacterial populations belonging to Bacteroidetes most commonly possessed ESBL genes followed by members of Enterobacteriaceae.
  • Overall, this study highlights variable, persistent effects of IMM ceftiofur treatment on the gut microbiome and resistome in dairy cattle. Antibiotic-treated cattle had an increased abundance of specific taxa and genes encoding ESBL production that persisted for 9 weeks. Fecal shedding of ESBL-producing Enterobacteriaceae, which was classified as a serious public health threat, varied across animals.


Evaluation of the Efficacy of a Lactobacilli-Based Teat Detergents for the Microbiota of Cows Teats Using an Untargeted Metabolomics Approach.
Yan R, Ji Z, Fan J, Li J, Ren Y. J Microbiol Biotechnol. 2023. 22;34(1):1-13.

  • Teat cleaning pre- and post-milking is important for the overall health and hygiene of dairy cows.
  • The purpose of this research was to evaluate the effectiveness of a teat detergents based on lactic acid bacteria according to changes in somatic cell count and cow-milk metabolites.
  • Sixty-nine raw milk samples were collected from 11 Holstein-Friesian cows in China during 12 days of teat cleaning. An ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry-based untargeted metabolomic approach was applied to detect metabolomic differences after treatment with lactic acid bacteria and chemical teat detergents in cows with subclinical mastitis.
  • The results suggest that the lactobacilli-based teat detergents could reduce somatic cell count and improve microhabitat of cow teat apex by adjusting the composition of metabolites. Furthermore, the somatic cell count could be decreased significantly within 10 days following the cleaning protocol.
  • Lactic acid bacteria have the potential to be applied as a substitution to teat chemical detergents before and after milking for maintenance of healthy teats and breasts. Further, larger scale validation work is required to support the findings of the current study.


Invited Review: “Probiotic” approaches to improving dairy production: reassessing “magic foo-foo dust”.
El Jeni R, Villot C, Callaway TR, et al. J Dairy Sci. 2023 Nov 8:S0022-0302(23)00790-7.

  • The gastrointestinal microbial consortium in dairy cattle is critical to determining the energetic status of the dairy cow, from birth through her final lactation. The ruminant’s microbial community can degrade a wide variety of feedstuffs which can impact growth, production rate and efficiency on the farm; but can also impact food safety, animal health, and environmental impacts of dairy production.
  • Gut microbial diversity and density are powerful tools that can be harnessed to benefit both producers and consumers.
  • The incentives in the US to develop Alternatives to Antibiotics for use in food animal production have been largely driven by the Veterinary Feed Directive and has led to an increased use of probiotic approaches to alter the gastrointestinal microbial community composition, resulting in improved heifer growth, milk production and efficiency, and animal health. However, the efficacy of Direct Fed Microbials (DFM) or probiotics in dairy cattle has been highly variable due to specific microbial ecological factors within the host gut of and its native microflora.
  • Interactions (both synergistic and antagonistic) between the microbial ecosystem and the host animal physiology (including epithelial cells, immune system, hormones, enzyme activities, and epigenetics) are critical to understanding why some probiotics work but others do not.
  • Increasing availability of Next Generation Sequencing (NGS) approaches provides novel insights into how probiotic approaches change the microbial community composition in the gut that can potentially impact animal health (e.g., diarrhea/scours, gut integrity, foodborne pathogens), as well as animal performance (e.g., growth, reproductive, productivity) and fermentation parameters (e.g., pH, short chain fatty acids [SCFA], methane production, and microbial profiles) of cattle.
  • However, it remains clear that all DFM are not created equal and their efficacy remains highly variable and dependent on stage of production and farm environment. Collectively, data have demonstrated that probiotic impacts are not limited to the simple mechanisms that have been traditionally hypothesized, but instead are part of a complex cascade of microbial ecological and host animal physiological effects that ultimately impact dairy production and profitability.

The intricate symbiotic relationship between lactic acid bacterial starters in the milk fermentation ecosystem. Yang S, Bai M, Kwok LY, Zhong Z, Sun Z. Crit Rev Food Sci Nutr. 2023 Nov 20:1-18.

  • Fermentation is one of the most effective methods of food preservation. Since ancient times, food has been fermented using lactic acid bacteria (LAB). Fermented milk is a very intricate fermentation ecosystem, and the microbial metabolism of fermented milk largely determines its metabolic properties.
  • The two most frequently used dairy starter strains are Streptococcus thermophilus( thermophilus) and Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus). To enhance both the culture growth rate and the flavor and quality of the fermented milk, it has long been customary to combine S. thermophilus and L. bulgaricus in milk fermentation due to their mutually beneficial and symbiotic relationship.
  • On the one hand, the symbiotic relationship is reflected by the nutrient co-dependence of the two microbes at the metabolic level. On the other hand, more complex interaction mechanisms, such as quorum sensing between cells, are involved.
  • This review summarizes the application of LAB in fermented dairy products and discusses the symbiotic mechanisms and interactions of milk LAB starter strains from the perspective of nutrient supply and intra- and interspecific quorum sensing. This review provides updated information and knowledge on microbial interactions in a fermented milk ecosystem.
Human Health and Nutrition

Relationship Between Dairy Intake and Hospitalization Risk and Disease Severity in Patients With COVID-19. Abbas-Hashemi SA, , Hekmatdoost A, et al. Clin Nutr Res. 2023 Oct 27;12(4):283-292.

  • Nutrition can play an important role in the treatment and prevention of COVID-19 due to its association with both immunity and inflammation. Micronutrients, especially vitamins A, C, D, as well as zinc and selenium, are important modulators of the immune system. Dairy is one of the rich sources of these micronutrients.
  • The zinc and selenium content of dairy has a protective role against inflammation, oxidative stress, and free radical damage. Also, vitamins B6 and B12, along with zinc and selenium, in dairy products can improve innate and adaptive immune responses through upregulating differentiation and proliferation of T and B cells. These nutrients also contribute to cell-mediated immunity and stimulate antibody production and function.
  • Antimicrobial and anti-inflammatory activity are other features of these micronutrients. The importance of these micronutrients in maintaining the structural and functional integrity of physical barriers including the intestinal lining and the respiratory tract has also been proven. Fermented milk consumption has also been shown to be associated with a reduced risk of mortality from COVID-19. These effects have been attributed in part to dairy peptides that, in addition to their antioxidant effects, have inhibitory activity on the angiotensin-converting enzyme.
  • The aim of this study was to investigate whether dairy intake was associated with the severity of coronavirus disease 2019 (COVID-19) disease and the probability of hospitalization of patients.
  • This cross-sectional study was conducted on 141 patients with COVID-19 with an average age of 46.23 ± 15.88 years.
  • The risk of hospitalization in the highest tertile of dairy intake was 31% lower than in the lowest tertile. Higher milk and yogurt intake was associated with a reduced risk of hospitalization due to COVID-19. Patients in the third tertiles were about 65% and 12% less likely to be hospitalized than those in the first tertile, respectively.
  • Dairy consumption, especially low-fat ones, was associated with a lower risk of hospitalization due to COVID-19 and lower severity of COVID-19.

Association of probiotic ingestion with serum sex steroid hormones among pre- and postmenopausal women from the NHANES, 2013-2016. Zou S, Yang X, Li N, Wang H, Gui J, Li J. PLoS One. 2023 Nov 16;18(11):e0294436.

  • Sex hormone-related diseases, encompassing a wide range of conditions from reproductive disorders to certain cancers, pose significant health challenges worldwide. Recent scientific investigations have highlighted the intricate interplay between the gut microbiome and sex hormone regulation, indicating the potential for microbiota-targeted interventions in the management of such diseases.
  • Although individual studies have elucidated the influence of the gut microbiome on sex hormones, a comprehensive cross-sectional examination of the population-wide prevalence of probiotic intake and its correlation with sex hormones is still lacking.
  • This study aimed to evaluate the association of probiotic ingestion with sex hormones in pre- and post-menopausal women.
  • Researchers conducted an observational cohort study comprising a nationally representative sample of adults who participated in the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2016. Probiotic ingestion was considered when a subject reported yogurt or probiotic supplement consumption during the 24-h dietary recall or during the Dietary Supplement Use 30-Day questionnaire. A survey-weighted generalized linear model was used to analyze the association between probiotic intake and female/male sex hormones.
  • This study results included 2,699 women, with 537 of them consuming yogurt and/or dietary supplements containing probiotics, while the remaining 2,162 women did not consume any probiotics.
  • The findings indicated that there were associations between probiotic intake and sex hormone levels in premenopausal and postmenopausal women. For premenopausal women, probiotic intake was positively associated with estradiol levels. On the contrary, in postmenopausal women, probiotic intake was inversely associated with total testosterone levels.
  • In conclusion, this study indicated that probiotic consumption was associated with higher estradiol level in premenopausal women and lower testosterone level in postmenopausal women. Probiotic intake might be a sensible strategy for preventing sex hormone-related diseases.

Dairy Intake Modifies the Level of the Bile Acid Precursor and Its Correlation with Serum Proteins Associated with Cholesterol Clearance in Subjects with Hyperinsulinemia. Mahdavi A, Trottier J, Barbier O, Lebel M, Rudkowska I. Nutrients. 2023 Nov 7;15(22):4707.

  • Bile acids regulate glucose homeostasis and lipid metabolism. Further, the levels of bile acids can be influenced by the intake of dairy products. Although the serum proteome can provide information on the biological pathways associated with different metabolites, it is unknown whether the intake of dairy modifies such associations between bile acids and the proteome.
  • The objectives of this study were to examine plasma bile acid profiles, find the correlations between bile acids and lipid as well as glycemic markers, and to uncover the correlation between bile acids and proteins after high dairy (HD) and adequate dairy (AD) intake among 25 overweight individuals with hyperinsulinemia.
  • In this randomized crossover-trial study, hyperinsulinemia adults were randomized to both HD (≥4 servings/day) and AD (≤2 servings/day) for 6 weeks. Measurements and analyses were performed on before- as well as after- AD and HD conditions.
  • The results indicated that plasma 7α-hydroxy-4-cholesten-3-one (7AC4) increased after HD in comparison with before HD intake. After adjusting for BMI, age, and sex, 7AC4 positively correlated with triglyceride levels in the pre-AD and post-HD. Further, 7AC4 correlated positively with proteins associated with high-density lipoprotein particle remodeling pathway and reverse cholesterol transport only after HD consumption.
  • Thus, the consumption of higher dairy intake modifies the association between 7AC4-a biomarker for bile acid synthesis-and serum proteins involved in cholesterol clearance. Overall, higher dairy consumption may have a positive effect on cholesterol metabolism in subjects at risk of type 2 diabetes.

Lactose malabsorption and intolerance: What is the correct management in older adults? Gallo A, Pellegrino S, Lipari A, Pero E, Montalto M, et al. Clin Nutr. 2023;42(12):2540-2545.

  • Lactose malabsorption is a very common condition due to intestinal lactase deficiency. However, lactose malabsorption does not necessarily result in gastrointestinal symptoms, i.e. lactose intolerance, which occurs in approximately one third of those with lactase deficiency.
  • In the absence of well-established guidelines, the common therapeutic approach tends to exclude milk and dairy products from the diet. However, this strategy may have serious nutritional disadvantages. Mainly in particular categories, such as the older adults, the approach to lactose malabsorption may deserve careful considerations.
  • Milk and dairy products are an important supply of a wide range of nutrients that contribute to meet the nutritional needs in different life stages. Dietary composition can significantly impact the mechanisms leading to age-related loss of bone mineral density, skeletal muscle mass or function and overall risk of sarcopenia.
  • Moreover, in the latest years, different lines of evidence have highlighted an association between dairy intake and prevention of chronic diseases as well as all-cause mortality. The aim of this opinion paper is to provide an overview of lactose malabsorption and intolerance in the older adults and their implications in clinical practice.

Infant Milk Formula with Large, Milk Phospholipid-coated Lipid Droplets Enriched in Dairy Lipids Affects Body Mass Index Trajectories and Blood Pressure at School Age: Follow-up of a Randomized Controlled Trial. Abrahamse-Berkeveld M, Mercurius Study Group, et al. Am J Clin Nutr. 2023 Nov 15:S0002-9165(23)66191-X.

  • Human milk comprises large fat globules enveloped by a native phospholipid membrane, whereas infant formulas contain small, protein-coated lipid droplets. Previous experimental studies indicated that mimicking the architecture of human milk lipid droplets in infant milk formula alters lipid metabolism with lasting beneficial impact on later metabolic health.
  • The objective of this research was to evaluate in a follow-up study of a randomized, controlled trial whether a Concept infant milk formula with large, milk phospholipid-coated lipid droplets enriched with dairy lipids beneficially impacts long-term body mass index (BMI in kg/m2) trajectories and blood pressure at school age.
  • Fully formula-fed infants were randomly assigned to Concept formula (n = 115) or Control formula with conventional, small lipid droplets containing vegetable oils (n = 108) for the first 4 months of age. A group of 88 breastfed infants served as a reference. During follow-up, anthropometrics were collected at 1, 3, 4, and 5 years of age, and blood pressure only at the last visit.
  • Compared to Control, Concept group children had consistently lower mean BMI values during follow-up, with the most marked difference at 1 year of age: mean values were close to the breastfed group. Contrary, the mean BMI values of the Control group were higher compared with the breastfed group during follow-up from 1 to 5 years of age. At 5 years of age, the Concept group had a lower mean diastolic and arterial blood pressure compared with the Control group; -4.3mm Hg and -3.7 mm Hg, respectively.
  • In conclusion, early life feeding of an innovative infant milk formula with large, milk phospholipid-coated lipid droplets enriched with dairy lipids results in a BMI trajectory closer to breastfed infants and a lower blood pressure at school age.

Bifidobacteria in Fermented Dairy Foods: A Health Beneficial Outlook. Jena R, Choudhury PK. Probiotics Antimicrob Proteins. 2023 Nov 18.

  • Bifidobacteria, frequently present in the human gastrointestinal tract, play a crucial role in preserving gut health and are mostly recognized as beneficial probiotic microorganisms. They are associated with fermenting complex carbohydrates, resulting in the production of short-chain fatty acids, bioactive peptides, exopolysaccharides, and vitamins, which provide energy and contribute to gut homeostasis.
  • In light of these findings, research in food processing technologies has harnessed probiotic bacteria such as lactobacilli and bifidobacteria for the formulation of a wide range of fermented dairy products, ensuring their maximum survival and contributing to the development of distinctive quality characteristics and therapeutic benefits.
  • Despite the increased interest in probiotic dairy products, introducing bifidobacteria into the dairy food chain has proved to be complicated. However, survival of Bifidobacterium species is conditioned by strain of bacteria used, metabolic interactions with lactic acid bacteria (LAB), fermentation parameters, and the temperature of storage and preservation of the dairy products.
  • Furthermore, fortification of dairy foods and whey beverages with bifidobacteria have ability to change physicochemical and rheological properties beyond economic value of dairy products.
  • In summary, this review underscores the significance of bifidobacteria as probiotics in diverse fermented dairy foods and accentuates their positive impact on human health. By enhancing our comprehension of the beneficial repercussions associated with the consumption of bifidobacteria-rich products, we aim to encourage individuals to embrace these probiotics as a means of promoting holistic health.

Potential of milk-derived bioactive peptides as antidiabetic, antihypertensive, and xanthine oxidase inhibitors: a comprehensive bibliometric analysis and updated review. Bellaver EH, Kempka AP. Amino Acids. 2023 Nov 8.

  • Bioactive peptides consist of small protein fragments, which are inactive in their original conformation, and they become active when released from these through enzymatic hydrolysis or fermentation processes. The bioactivity of such peptides has been extensively reported in the literature as contributors to organic homeostasis processes, as well as in immunomodulation, organism defense against oxidative processes, among others.
  • In this study, reports of the activity of BPs isolated from milk with the potential glycemic control, antihypertensive activity, and inhibitors of uric acid formation were compiled.
  • A systematic literature review and bibliometric analysis were conducted, using the PICO strategy for the research.
  • The temporal analysis of publications revealed a growing interest in the investigation of bioactive peptides with potential antidiabetic, antihypertensive, and xanthine oxidase inhibitory activities, using dairy sources as products for their extraction. The literature analysis also revealed an increase in research involving non-bovine dairy products for bioactive peptide extraction.
  • The collaboration network among authors exhibited weaknesses in scientific cooperation. Regarding the analysis of keywords, the usage of terms such as “bioactive peptides”, “antioxidant”, “antihypertensive”, and “diabetes” was evident, constituting the main research clusters.
  • Peptides with low molecular weight, typically < 10 kDa, of hydrophobic nature with aliphatic and aromatic chains, have significant implications in molecular interactions for the required activities.
  • Although there is a growing interest in the industry regarding the utilization of bioactive peptides as potential drugs, there is a need to address gaps related to elucidating their interactions with cellular targets and their use in human therapy.
Innovation, Economics, and Dairy Alternatives

Application of Microsatellites to Trace the Dairy Products Back to the Farm of Origin. Perga S, Biolatti C, Modesto P, et al. Foods. 2023 Nov 15;12(22):4131.

  • The increasing number of food frauds, mainly targeting high quality products, is a rising concern among producers and authorities appointed to food controls. Therefore, the development or implementation of methods to reveal frauds is desired.
  • The genetic traceability of traditional or high-quality dairy products (i.e., products of protected designation of origin, PDO) represents a challenging issue due to the technical problems that arise.
  • The aim of the study was to set up a genetic tool for the origin traceability of dairy products.
  • Researchers investigated the use of Short Tandem Repeats (STRs) to assign milk and cheese to the corresponding producer. Two farms were included in the study, and the blood of the cows, bulk milk, and derived cheese were sampled monthly for one year.
  • Twenty STRs were selected and Polymerase Chain Reactions for each locus were carried out.
  • The results showed that bulk milk and derived cheese express an STR profile composed of a subset of STRs of the lactating animals. A bioinformatics tool was used for the exclusion analysis.
  • The study allowed the identification of a panel of 20 markers useful for the traceability of milk and cheeses, and its effectiveness in the traceability of dairy products obtained from small producers was demonstrated.

Recent developments in ultrasound approach for preservation of animal origin foods. Bariya AR, Rathod NB, Rocha JM, et al. Ultrason Sonochem. 2023 Nov 2;101:106676.

  • There has been a rise in the demand for food products that have undergone minimal processing or have been subjected to non-thermal techniques. Ultrasound is a contemporary non-thermal technology that is currently being extensively evaluated for its potential to preserve highly perishable foods, while also contributing positively to the economy and environment.
  • Livestock-derived food products, such as meat, milk, eggs, and seafood, are widely recognized for their high nutritional value. These products are notably rich in proteins and quality fats, rendering them particularly vulnerable to oxidative and microbial spoilage.
  • Ultrasound has exhibited significant antimicrobial properties, as well as the ability to deactivate enzymes and enhance mass transfer.
  • The present review centers on the production and classification of ultrasound, as well as its recent implementation in the context of livestock-derived food products. The commercial applications, advantages, and limitations of the subject matter are also subject to scrutiny.
  • The review indicated that ultrasound technology can be effectively utilized in food products derived from livestock, leading to favorable outcomes in terms of prolonging the shelf life of food while preserving its nutritional, functional, and sensory attributes.
  • It is recommended that additional research be conducted to investigate the effects of ultrasound processing on nutrient bioavailability and extraction. The implementation of hurdle technology can effectively identify and mitigate the lower inactivation of certain microorganisms or vegetative cells.

Effects of Different Prebiotics on the Gel Properties of Milk Protein and the Structural Features of Yogurt. Li D, Lai M, Wang P, Ma H, Li H, Wang R, Wu X. Gels. 2023 Oct 30;9(11):863.

  • The impact of prebiotics on the structural characteristics of yogurt is an important aspect of evaluating its functional properties.
  • This study aimed to evaluate and compare the effects of several commonly used prebiotics, including fructooligosaccharide (FOS), galactooligosaccharide (GOS), inulin (INU), polydextrose (PDX), and xylooligosaccharide (XOS), on the gel properties of milk protein and the structural features, with respect to the texture and rheology, of stirred yogurt during and after fermentation.
  • The results revealed that the supplementation of INU, PDX, and XOS was involved in the construction of protein networks during fermentation, promoting a viscous and more elastic gel structure, due to the enhanced protein-water interactions. This resulted in a significant increase in structural stability, firmness, cohesiveness, and rheology and a significant decrease in the loss of yogurt during centrifugation.
  • Conversely, the supplementation of GOS and FOS did not appear to be involved in the construction of the protein network and barely affected the rheological properties of the gel during fermentation. However, a significant increase in viscosity and firmness, and a slight decrease in loss during centrifugation were still observed in the yogurt.
  • These findings could be useful for a comprehensive assessment of the application potential of these prebiotics in yogurt, when combined with their respective prebiotic properties.

Shaping Future Foods through Fermentation of Side Streams: Microbial, Chemical, and Physical Characteristics of Fermented Blends from Sunflower Seed Press Cake and Cheese Whey. Raak N, Mangieri N, Foschino R, Corredig M. Foods. 2023 Nov 12;12(22):4099.

  • The current food system suffers from the inefficient use of resources, including the generation of side streams of low economic value that still contain nutritional components.
  • One potential approach to reach a more sustainable food system is to reintroduce such side streams into a circular value chain and valorize them in novel food products, preferably in an unrefined or minimally refined manner.
  • Blending side streams from different industries might be a suitable way to improve the nutritional value of the final matrix.
  • In this study, sunflower seed press cake and cheese whey were combined to obtain matrices containing valuable proteins, structuring polysaccharides, as well as lactose and minerals facilitating fermentation with three different co-cultures of lactic acid bacteria and yeasts.
  • Fermentation for 48 h at 26 °C decreased the pH from ~6.3 to ~4.7 and enhanced the storage stability of the blends with no effect on their rheological properties and microstructure.
  • This research demonstrates the potential of fermentation as a mean to stabilize side stream blends while only minimally affecting their physical appearance.

Optimal combination of cow and quinoa milk for manufacturing of functional fermented milk with high levels of antioxidant, essential amino acids and probiotics. El-Menawy RK, Mohamed DM, Ismail MM, Hassan AM. Sci Rep. 2023 Nov 24;13(1):20638.

  • The aim of this research was to produce Rayeb milk, a bio-fermented milk product that has important benefits for health and nutrition.
  • The Rayeb milk was divided into five different treatments: T1 from cow milk, T2 from quinoa milk, T3 from a mixture of cow and quinoa milk (50%:50%), T4 from a mixture of cow and quinoa milk (75%:25%), and T5 from a mixture of cow and quinoa milk (25%:75%).
  • As a starting culture, ABT-5 culture was used.
  • The results demonstrated that blending quinoa milk with cow milk increased the total solids, fat, total protein, pH, acetaldehyde, and diacetyl values of the resulting Rayeb milk. Additionally, the total phenolic content, antioxidant activity, minerals, and amino acids-particularly important amino acids-in Rayeb milk with quinoa milk were higher.
  • In Rayeb milk prepared from a cow and quinoa milk mixture, Lactobacillus acidophilus and Bifidobacterium bifidum were highly stimulated. All Rayeb milk samples, particularly those that contained quinoa milk, possessed more bifidobacteria than the recommended count of 106 cfu g-1 for use as a probiotic.
  • Based on the sensory evaluation results, it is possible to manufacture a bio-Rayeb milk acceptable to the consumer and has a high nutritional and health values using a mixture of cow milk and quinoa milk (75%:25% or 50%:50%) and ABT-5 culture.