Dairy products contain complex types and contents of proteins, lipids, and lactose. The Maillard reaction (MR) occurs between proteins and reducing sugars during the processing and storage of dairy products. Maillard reaction products (MRPs) have garnered attention for their potential antioxidant activity. MRPs include melanoidins, reductones, and volatile heterocyclic compounds, which affect flavor and color. Relevant literature was identified through a structured search of PubMed and Web of Science; studies were included if they investigated MRPs in dairy products and reported antioxidant-related outcomes. This review offers a comprehensive overview of the MR in dairy products, systematically investigating the influence of protein, reducing sugars, and their ratios, as well as reaction conditions (process technology, temperature, time, pH, and water activity) on the formation and antioxidant activity of MRPs. The review also covers current applications and the future potential of MRPs as natural antioxidants in dairy products. Although MRPs effectively delay lipid oxidation and enhance stability in dairy products, research on their molecular structure and antioxidant mechanisms remains insufficient. Future research should focus on understanding the multifactorial synergistic effects within the complex dairy matrix, elucidating the molecular structure and extraction of antioxidant substances, and developing regulatory techniques to balance the antioxidant properties of MRPs with the safety concerns of potential harmful byproducts.
ABSTRACT: Small ruminant milk may offer a viable alternative to cow milk, whereas human milk, the gold standard for infant nutrition, exhibits dynamic composition. This study analyzed the milk fat globules (MFG) particle size, fatty acid (FA) composition, and milk fat globule membrane (MFGM) proteome in human, goat, and sheep colostrum and mature milk. The smallest and largest average MFG particle sizes were identified in goat colostrum and sheep mature milk, respectively. Unsaturated FA were most prevalent in human colostrum (HC; 70.04%), whereas small ruminant milks were characterized by a higher proportion of saturated FA (57.07%–77.77%). The differential expression of FA is speculated to be associated with the variation in FA metabolic proteins on MFGM. A total of 1,658 MFGM proteins were identified. Compared with small ruminant milks, glycolysis-related proteins, such as phosphoglycerate mutase and pyruvate kinase, and antigen-presenting proteins, such as toll-like receptors and HLA molecules, were most abundant in HC, with higher levels of antioxidant-related proteins observed in human mature milk (HM). By emphasizing the differences in MFG between HC, HM, and small ruminant milk from the perspectives of particle size, FA, and proteomics, this study provides data supporting the personalized improvement of infant formula.
Barjam Hasanllari, Benjamin P. Willing, Liang Li
et al.
The dairy industry relies on the health and well-being of dairy cows for the optimal production of milk and dairy products. Mastitis, a prevalent and economically burdensome disease characterized by udder inflammation, poses significant challenges to dairy farmers worldwide. In this study, we employed peptidomics to explore the peptide profiles of dry secretions collected from dairy cows at specific intervals during the dry-off period. We hypothesized that alterations in peptide composition during the dry period may influence pathogen proliferation and immune cell functioning, thereby impacting mastitis susceptibility. Our objectives were to investigate the following: (i) differences in peptide composition and alterations between healthy cows and those with subclinical mastitis, potentially serving as biomarkers for early mastitis detection and offering insights into udder bioprocesses; (ii) variations in peptide profiles between the early (day 2) and later (day 21) stages of the dry-off period during both health conditions. Dry secretions were collected from 16 udder quarters of 8 cows at two defined time points—Day 2 (D2) and Day 21 (D21)—during the dry period. Our results revealed distinct peptide patterns between healthy and subclinical mastitis cows, as well as temporal variations in peptide profiles throughout the dry-off period. A total of 1235 peptides, originating from 59 distinct proteins (primarily β-casein), were detected across the four groups: subclinical mastitis day 21 (SCM-D21), subclinical mastitis day 2 (SCM-D2), healthy day 21 (H-D21), and healthy day 2 (H-D2). Furthermore, 56 out of the 1235 peptides identified in total matched known functional peptides, with a total of 17 different functions including antimicrobial, antioxidant, and immunomodulatory, suggesting their potential roles in mastitis pathogenesis and mammary gland physiology. Comparative analyses revealed changes in the levels of these functional peptides across the four different groups, suggesting their potential roles in regulating immune responses, oxidative stress, inflammatory processes, and other biological activities during subclinical mastitis and the dry-off period. These findings provide valuable insights into mastitis detection, management strategies, and dairy cow health monitoring, offering promising avenues for enhancing milk quality and dairy industry sustainability.
Muhammad Aqeel, Ahmed Sohaib, Muhammad Iqbal
et al.
ABSTRACT: Milk adulteration poses a global concern, with developing countries facing higher risks due to unsatisfactory monitoring systems and policies. Surprisingly, this common issue has often been overlooked in many countries. Contrary to popular belief, adulterants in milk can result in severe health risks, potentially leading to fatal diseases. Detecting and categorizing milk adulteration is crucial for consumer safety and the dairy industry. This research is divided into 2 breakthroughs, destructive and nondestructive methods. In the destructive method, the Lactoscan system was used for qualitative analysis: SNF, density, fat, lactose, conductivity, solids, protein, temperature, and pH level. The research also examines nondistractive hyperspectral imaging (HSI) through HSI Specim Fx-10 (397–1,003 nm; Specim, Spectral Imaging Ltd., Oulu, Finland) analysis to detect various phases of milk adulteration for accurate and user-friendly imaging-based adulterant detection and categorization. Preprocessing involves radiometric correction, image resizing, region of interest selection for feature extraction, and empirical line method to calculate spectral reflectance signature. Machine learning techniques (logistic regression, decision tree, support vector machine, and linear discriminant analysis [LDA]), are employed, with LDA excelling in adulteration identification by learning the spectral signatures. These algorithms are trained and validated using a developed milk adulteration dataset. Training, testing, and validation accuracy, precision, recall, F1 score, kappa, and Matthew's correlation coefficient metrics showcase the effectiveness of the proposed pipeline, outclassing numerous state-of-the-art approaches with a validation accuracy of 100%. In conclusion, this study established a multiclass model capable of detecting milk adulterant behavior, showing significant practical application for milk quality assessment.
ABSTRACT: In the current study, whey protein fractal assembly (FA) particles were manufactured and used as emulsifying agent to manufacture oil-in-water (o/w) emulsion system, namely FA emulsion. The cold-set gelation behavior of FA emulsion was investigated in terms of gel-phase stability, rheology, and tribology. Fractal assembly particles were prepared by heating whey protein isolate (WPI) solution (90 g·L−1) at 80°C for 24 h. The fractal morphology of FA particles was observed using transmission electron microscopy. The “protein aggregation index” for WPI solution and FA sol was found as (mean ±SD) 4.3% ± 0.6% and 78.2% ± 0.7%, respectively. The FA sol had z-average diameter of 133.16 nm ± 3.59 nm. The WPI and FA dispersion systems had similar isoelectric points (IEP) at ∼pH 4.6. FA particles had higher surface hydrophobicity as compared with WPI. The WPI and FA stabilized emulsions showed similar droplet size distribution, however, the FA emulsion had higher surface charge than the WPI emulsion. The WPI and FA emulsions were then used to fabricate 18 cold-set gels by manipulating pH (4.6, 5.8, and 7.0) and added levels of Ca2+ (0, 5, and 10 mM), in which 9 gels derived from WPI emulsion were used as control samples. The WPI emulsion was not able to form self-supported and phase-stable gel under each gelation condition tested in this work, whereas FA emulsion gels demonstrated a superior syneresis stability. According to the large-amplitude oscillatory shear rheology characterization, FA emulsion gels showed both strain stiffening-softening transition and shear-thinning-thickening transition behaviors depending on the applied strain and oscillatory frequency. Lissajous-Bowditch plots revealed unsteady rheological behavior, ranging from perfect plastic to Bingham plastic depending upon the applied angular frequency. The selected FA emulsion gels demonstrated acceptable lubrication behaviors. These findings indicate that the characterized FA emulsion gels may be used as protein-based texturizers in diversified food matrixes.
ABSTRACT: This study investigated the pattern of 6 behavioral parameters in Holstein dairy cows under heat stress (HS) conditions using a generalized additive mixed model (GAMM) statistical approach, while also evaluating the effectiveness of a commercial electrolyte, osmolyte, and antioxidant blend in mitigating HS-induced adverse effects. The trial was conducted during a severe Italian summer on 84 multiparous dairy cows in the Central Italy, divided into 4 balanced groups (2 treated and 2 control) of 21 cows each. All animals received the same diet, and the treatment groups were supplemented with 3,150 g/d of the additive. Behavioral parameters, namely low activity (LA), medium activity (MA), high activity (HA), rumination time (RUM), eating time (ET), and heavy breathing (OH), were monitored using neck collar sensors. Generalized additive mixed models were used to analyze trajectory changes of these parameters over time and climatic conditions. Results indicated significant variations in only one activity parameter, with treated cows showing increased MA with rising temperature-humidity index (THI). Eating time declined with increasing HS, particularly in the treated group, suggesting potential HS relief. Rumination time decreased with increasing HS levels but increased also with milk yield and lactation stage. As expected, heavy breathing significantly increased with THI, especially beyond THI 80, and was influenced by milk yield and lactation stage but not by the treatment. The use of GAMM enhanced visualization and understanding of severe climatic conditions' effects on behavioral parameters.
Fermentation is widely used in the processing of dairy, meat, and plant products. Due to the growing popularity of plant diets and the health benefits of consuming fermented products, there has been growing interest in the fermentation of plant products and the selection of microorganisms suitable for this process. The review provides a brief overview of lactic acid bacteria (LAB) and their use in fermentation of legumes and legume-based beverages. Its scope also extends to prebiotic ingredients present in legumes and legume-based beverages that can support the growth of LAB. Legumes are a suitable matrix for the production of plant-based beverages, which are the most popular products among dairy alternatives. Legumes and legume-based beverages have been successfully fermented with LAB. Legumes are a natural source of ingredients with prebiotic properties, including oligosaccharides, resistant starch, polyphenols, and isoflavones. These compounds provide a broad range of important physiological benefits, including anti-inflammatory and immune regulation, as well as anti-cancer properties and metabolic regulation. The properties of legumes make it possible to use them to create synbiotic food, which is a source of probiotics and prebiotics.
EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP), Claude Lambré, José Manuel Barat Baviera
et al.
Abstract The food enzyme mucorpepsin (EC 3.4.23.23) is produced with the non‐genetically modified Rhizomucor miehei strain M19‐21 by Meito Sangyo Co., Ltd. The native enzyme can be chemically modified to produce a more thermolabile form. The food enzyme was considered free from viable cells of the production organism. It is intended to be used in the processing of dairy products for the production of cheese and fermented dairy products. Dietary exposure to the food enzyme‐total organic solids (TOS) was estimated to be up to 0.108 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 226 mg TOS/kg bw per day, the highest dose tested, which, when compared with the estimated dietary exposure, results in a margin of exposure of at least 2093. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and four matches to respiratory allergens and one match to a food allergen (mustard) were found. The Panel considered that the risk of allergic reactions upon dietary exposure to this food enzyme, particularly in individuals sensitised to mustard proteins, cannot be excluded. Based on the data provided, the Panel concluded that both the native and thermolabile forms of this food enzyme do not give rise to safety concerns, under the intended conditions of use.
Nutrition. Foods and food supply, Chemical technology
The extremely high costs of manufacturing transglutaminase from animal origin (EC 2.3.2.13) have prompted scientists to search for new sources of this enzyme. Interdisciplinary efforts have been aimed at producing enzymes synthesised by microorganisms which may have a wider scope of use. Transglutaminase is an enzyme that catalyses the formation of isopeptide bonds between proteins. Its cross-linking property is widely used in various processes: to manufacture cheese and other dairy products, in meat processing, to produce edible films and to manufacture bakery products. Transglutaminase has considerable potential to improve the firmness, viscosity, elasticity and water-binding capacity of food products. In 1989, microbial transglutaminase was isolated from Streptoverticillium sp. Its characterisation indicated that this isoform could be extremely useful as a biotechnological tool in the food industry. Currently, enzymatic preparations are used in almost all industrial branches because of their wide variety and low costs associated with their biotechnical production processes. This paper presents an overview of the literature addressing the characteristics and applications of transglutaminase.
Milk is a highly nutritious food that contains an array of macro and micro components, scientifically proven to be beneficial to human health. While the composition of milk is influenced by a variety of factors, such as genetics, health, lactation stage etc., the animal’s diet remains a key mechanism by which its nutrition and processing characteristics can be altered. Pasture feeding has been demonstrated to have a positive impact on the nutrient profile of milk, increasing the content of some beneficial nutrients such as Omega-3 polyunsaturated fatty acids, vaccenic acid, and conjugated linoleic acid (CLA), while reducing the levels of Omega-6 fatty acids and palmitic acid. These resultant alterations to the nutritional profile of “Grass-Fed” milk resonate with consumers that desire healthy, “natural”, and sustainable dairy products. This review provides a comprehensive comparison of the impact that pasture and non-pasture feeding systems have on bovine milk composition from a nutritional and functional (processability) perspective, highlighting factors that will be of interest to dairy farmers, processors, and consumers.
The market for plant-based dairy-type products is growing as consumers replace bovine milk in their diet, for medical reasons or as a lifestyle choice. A screening of 17 different commercial plant-based milk substitutes based on different cereals, nuts and legumes was performed, including the evaluation of physicochemical and glycaemic properties. Half of the analysed samples had low or no protein contents (<0.5 %). Only samples based on soya showed considerable high protein contents, matching the value of cow’s milk (3.7 %). An in-vitro method was used to predict the glycaemic index. In general, the glycaemic index values ranged from 47 for bovine milk to 64 (almond-based) and up to 100 for rice-based samples. Most of the plant-based milk substitutes were highly unstable with separation rates up to 54.39 %/h. This study demonstrated that nutritional and physicochemical properties of plant-based milk substitutes are strongly dependent on the plant source, processing and fortification. Most products showed low nutritional qualities. Therefore, consumer awareness is important when plant-based milk substitutes are used as an alternative to cow’s milk in the diet.
ABSTRACT: Milk fever is one of the most historically relevant diseases of dairy cows. It is caused by tremendous calcium (Ca) expenditure at the initiation of lactation, so severe that cows can no longer stand and, if left untreated, die. Fortunately, through prepartum nutritional improvements, this version of clinical hypocalcemia is rare in the United States. Nonetheless, the opinion that all versions of postpartum hypocalcemia are detrimental remains pervasive, which is particularly significant given that 50% of cows are subclinically hypocalcemic after calving. This has led to a variety of available management and treatment strategies, ranging from prepartum dietary programs to postpartum Ca gels and boluses, targeted at preventing hypocalcemia in dairy cows. Recent research has determined that postpartum dairy cows can experience different types of subclinical hypocalcemia: transient, persistent, or delayed. We now know cows experiencing transient hypocalcemia as part of the homeorhetic adaptation to lactation are the highest milk producers in modern dairy herds, whereas cows with hypocalcemia several days after calving experience disease and losses in milk production. Therefore, it is wrong to assume all postpartum hypocalcemia is detrimental and that treatment of all cases is considered necessary and beneficial. Research indicates that milk synthesis at the onset of lactation contributes to immediate postpartum hypocalcemia, and that the mammary gland is a critical factor in management of Ca homeostasis. However, cows differ in their ability to manage this phenomenon, and it is possible that immediate postpartum influences such as dry matter intake, inflammation, and immune activation affect appropriate Ca regulation in the days following calving.
Xiao-Lin Wu, Asha M. Miles, Curtis P. Van Tassell
et al.
This study compared 3 correlational (best prediction, linear regression, and feed-forward neural networks) and 2 causal models (recursive structural equation model and recurrent neural networks) for estimating lactation milk yields. The correlational models assumed associations between test-day milk yields (health conditions), while the casual models postulated unidirectional recursive effects between these test-day variables. Wood lactation curves were used to simulate the data and served as a benchmark model. Individual Wood lactation curves provided an excellent parametric interpretation of lactation dynamics, with their prediction accuracies depending on the coverage of the lactation curve dynamics. Best prediction outperformed other models in the absence of mastitis but was suboptimal when mastitis was present and unaccounted for. Recurrent neural networks yielded the highest accuracy when mastitis was present. Although causal models facilitated the inference about the causality underlying lactation, precisely capturing the causal relationships was challenging because the underlying biology was complex. Misspecification of recursive effects in the recursive structural equation model resulted in a loss of accuracy. Hence, modeling causal relationships does not necessarily guarantee improved accuracies. In practice, a parsimonious model is preferred, balancing model complexity and accuracy. In addition to the choice of statistical models, the proper accounting for factors and covariates affecting milk yields is equally crucial.
Microbiology is important to food safety, production, processing, preservation, and storage. Microbes such as bacteria, molds, and yeasts are employed for the foods production and food ingredients such as production of wine, beer, bakery, and dairy products. On the other hand, the growth and contamination of spoilage and pathogenic microorganisms is considered as one of the main causes to loss of foodstuff nowadays. Although technology, hygienic strategies, and traceability are important factors to prevent and delay microbial growth and contamination, food remains susceptible to spoilage and activity of pathogen microorganisms. Food loss by either spoilage or contaminated food affects food industry and consumers leading to economic losses and increased hospitalization costs. This chapter focuses on general aspects, characteristics, and importance of main microorganisms (bacteria, yeasts, molds, virus, and parasites) involved in food spoilage or contamination: known and recently discovered species; defects and alterations in foodstuff; most common food associated with each foodborne disease; resistance to thermal processing; occurrence in different countries; outbreaks; and associated symptoms.