Dairy By-products Research Articles

Neuroprotective effects of whey and buttermilk-based formulas on a DSS-induced colitis murine model.

Inflammatory bowel disease is a gut-brain axis disorder that comprises chronic inflammatory conditions affecting the gastrointestinal tract, where alterations in the mood of patients are common. Gut-brain axis is a bidirectional communication that link gut and brain. The close association between inflammatory bowel disease and neuroinflammation has far-reaching implications, as is increasingly recognized as a contributing factor to neuropsychiatric and neurodegenerative diseases. The increasing prevalence and high economic cost, together with the loss of life quality of people suffering from these diseases, point to the need to find alternatives to alleviate them. Exploring new therapeutic avenues prompts us to consider the potential benefits of milk fractions, taking advantage of the use of dairy by-products, such as whey and buttermilk. This study examines the impact of cow's whey- and buttermilk-based formulas supplemented with bovine lactoferrin and milk fat globule membrane on the expression of cytokines, as well as on the components of immune and serotonergic system of the brain in a murine model of DSS-induced colitis. Our results show the potential of these dairy by-products, especially whey, as functional foods in ameliorating neuroinflammation and safeguarding the central nervous system function amid the neurological complications induced or concomitant with intestinal inflammatory processes.

Buttermilk treatment strategies to obtain MFGM-enriched isolates and comprehensive characterization of their lipid and protein components

The extraction of Milk Fat Globule Membrane (MFGM) from dairy by-products, particularly buttermilk, involves a highly intricate procedures to obtain a bioactive isolate with multiple health benefits. This study delves into a laboratory ultrafiltration-based method enabling the acquisition of a concentrated MFGM isolate. Pre-ultrafiltration treatments, designed to clarify the sample, such as casein coagulation and the addition of sodium citrate, were examined to evaluate their impact on the lipid and protein components of the MFGM. Treatments combining rennet coagulation with centrifugation steps, as well as those combining rennet with sodium citrate, yielded highly pure MFGM isolates exhibiting a substantial concentration of polar lipids and a rich content of MFGM proteins. This laboratory investigation offers valuable insights into the potential industrial-scale applications of MFGM isolation and purification.

Current Trends in Food Processing By-Products as Sources of High Value-Added Compounds in Food Fortification.

Along the food production chain of animal, fish, and vegetable products, a huge amount of by-products are generated every year. Major nutritional, financial, and environmental advantages can be achieved by transforming them into functional ingredients for food formulation and fortification. In this review, we investigated various conventional and emerging treatments recently employed to obtain functional ingredients rich in proteins, fibers, and bioactive compounds from vegetables, fish, meat, and dairy by-products. The optimal enrichment level in food as well as the nutritional, techno-functional, and sensory properties of the final food were also discussed. Novel technologies such as ultrasounds, microwaves, and high pressure have been successfully adopted to enhance the extraction of target compounds. The functional ingredients, added both in liquid or powder form, were able to improve the nutritional quality and antioxidant potential of food, although high levels of fortification may cause undesired changes in texture and flavor. This review provides important considerations for further industrial scale-up.

Evaluation of In Vitro Antihypertensive and Anti-Inflammatory Properties of Dairy By-Products

Sweet whey (SW) and yogurt acid whey (YAW) are dairy by-products of the cheese-making process and Greek-style yogurt production, respectively. Both of them are considered pollutants with huge volumes of SW and YAW produced due to the growing demand for dairy products worldwide. Moreover, whey-derived peptides, resulting from fermentation as well as from further hydrolysis during digestion, have been associated with various biological activities. In the present study, the angiotensin-converting enzyme (ACE)-inhibitory activity of 48 SW samples and 33 YAW samples from bovine, ovine, caprine, and ovine/caprine milk obtained were evaluated. Additionally, the SW and YAW digestates and two of their fractions (smaller than 10 kDa, SW-D-P10 and YAW-D-P10, and smaller than 3 kDa, SW-D-P3 and YAW-D-P3), which were obtained after in vitro digestion and subsequent ultrafiltration, were also subjected to evaluation. Our data indicated that the D-P10 and D-P3 fractions exhibited higher ACE-inhibitory activity compared to the corresponding values before digestion. The ACE-inhibitory capacity after in vitro digestion was higher for the ovine SW samples compared to their bovine and caprine counterparts. The effect of the D-P3 fraction on the inhibition of nitric oxide (NO) production and the expression of a selected panel of immune-response-related genes in LPS-stimulated RAW 264.7 macrophages was also evaluated. Fractions from both dairy by-products inhibited NO production in LPS-stimulated RAW 264.7 cells. Especially, ovine SW-D-P3 showed a strong NO inhibitory activity and suppressed inducible nitric oxide synthase (Nos2) mRNA levels. However, YAW-D-P3 could not trigger neither the gene expression of inflammatory macrophage mediators Nos2 and cyclooxygenase-2 (Ptgs2) nor tumor necrosis factor-α (Tnf) and interleukin 6 (Il6) in LPS-stimulated murine macrophages regardless of animal origin. These findings suggest that in vitro digestion could enhance the production of ACE-inhibitory peptides in both dairy by-products, while SW from ovine origin displays higher potential as an anti-inflammatory agent, effectively preventing excessive NO production.

Orally self-disintegrating milk protein puffs enriched with food by-products for the elderly

Supercritical fluid extrusion (SCFX) processing was used to develop milk protein-based orally self-disintegrating puffs enriched with fruit and dairy by-products, designed specifically to cater to the needs of elderly population having swallowing issues and lactose intolerance. Lactose hydrolyzed skim milk powder (LHSMP) was also added in the formulation to mitigate lactose intolerance while LHSMP was also exploited as a precursor for the polymerization of galactose and lactose to generate galacto-oligosaccharides (GOS) in the puffs. This study for the first time took advantage of the unique features of SCFX processing for in-process GOS formation and enrichment of puffs, achieving GOS contents up to 0.48 g/30 g serving of puffs, thereby making them nutritionally superior and functionally attractive snacks. The estimated nutritional profile revealed that SCFX puffs contained higher levels of protein (16.3 g/30 g), fiber (1.6 g/30 g), phenolics and other valuable nutrients compared to the starch-rich, disintegrating Market Baby puffs.

Supercritical fluid extrusion of dairy and fruit products to generate GOS-enriched and nutritionally superior snack puffs

The consumption of ultra-processed snacks is often considered unhealthy because such foods generally are energy-dense with low nutritive value. They contain high levels of starch, fat, and sugar and low levels of essential nutrients such as fiber, protein, and bioactive compounds. Nutritionally balanced snack foods that cater to today’s on-the-go lifestyles and do not get in the way of better eating are in high demand. The present study aims to create nutritionally attractive extruded puffs by valorizing food manufacturing byproducts and to elucidate the uniqueness of hybrid extrusion processing and its effect on product quality parameters. Supercritical fluid extrusion (SCFX) was used to transform apple pomace, starch or dairy ingredient-based formulations into value-added products in a zero-waste system. Acid whey, a byproduct of yogurt and cheese manufacturing, was used in lieu of water in the extruder to mitigate environmental issues related to its disposal. The SCFX system was also used for in-process polymerization of galactose, sourced from lactose hydrolyzed skim milk powder (LHSMP), with lactose from milk protein concentrate (MPC) and acid whey sources to produce galacto-oligosaccharides (GOS), a prebiotic associated with various health benefits and making the product acceptable to lactose intolerant consumers. Analysis of the extruded puffs showed that a combination of pomace and dairy ingredients significantly improved the nutritional profile of the product, notably increasing the fiber (5.0 g/30 g serving), protein (13.6 g/30 g serving), bioactive compounds (phenolics 21.4 mg GAE/30 g and vitamin C 0.3 mg/30 g serving), minerals, and GOS (0.4 g/30 g serving) contents. A sensory acceptance test (n=91) showed that incorporation of fruit and dairy by-products in snacks either improved or maintained Just About Right (JAR) scores compared to Market Keto puffs. Overall, utilizing fruit pomace and acid whey in extruded products made by SCFX is not only able to generate nutritious and functional snacks with balanced nutrients profile, derived from inexpensive agro-food by-products feedstock, but also can help mitigate environmental and waste issues.

Peculiarities of proteins fractionation at electroactivation of whey

Food processing, which generates both by-products and waste, requires a revision of modern processes in the framework of the development of non-residual, environmentally friendly processes. Dairy by-products require the development of complex zero-waste technologies. Electroactivation is an emerging process to overcome those challenges, which allows for non-residual processing of milk by-products. Electroactivation, managing both the technological regimes and the geometric/technical parameters of the electrolyzers used to process different types of whey, allows both the electrofractionation of the whey proteins recovered in protein mineral concentrates enriched, under certain process conditions, with a certain protein content, but also the simultaneous isomerization of lactose into lactulose following two mechanisms, and creating a closed process cycle. The geometry of the electrolyzers and the content of the secondary liquid (anodic liquid) influence both the extraction and the formation of protein compounds enriched with alpha-lactalbumin, as well as the formation of a complex between calcium and isomerized lactulose.

Effect of ultra-high pressure homogenization on the antirotaviral activity of bovine milk whey

In the present study, ultra-high pressure homogenization (UHPH, 100–250 MPa) was applied on bovine whey. The ability of UHPH-treated whey to neutralize the bovine rotavirus strain WC3 was evaluated in vitro using a model of human intestinal epithelium. Results showed that whey homogenized at 100 and 200 MPa inhibited the rotavirus infection in a dose-response way, exhibiting >95% neutralization at 1.5 mg mL−1 protein concentration. However, after homogenization of whey at 250 MPa, a clear neutralization pattern could not be observed. This could be attributed to aggregation and/or denaturation of some bioactive proteins, as it has been evidenced in the electrophoretic profile of that sample. Interestingly, the fat fraction obtained from all UHPH-treated wheys, showed almost complete neutralization at 1 mg mL−1 protein concentration. Therefore, whey fractions could be used as functional ingredients in novel non-thermal processed products for the control of viral infections. Industrial relevanceThis study provides useful information to increase the commercial value of sweet, skimmed whey as a functional ingredient and its recognition as a natural source of antivirals. The use of emerging processing technologies, such as UHPH, could favor the preservation of certain bioactivity within the dairy by-product.

Revitalizing traditional Turkish tort cheese into spreadable form: Enhancing bioactive and sensory attributes with utilization of carob molasses pulp that is a food waste.

Tort cheese is a traditional cheese that is a gastronomically valuable product, especially in the Mediterranean Region of Turkey, obtained by prolonged boiling of whey, which is one of the most important dairy byproducts. Due to the difficulty of production and its short shelf life, this cheese, which is produced in limited quantities and has low nutritional value, is among the forgotten products. In this study, a spreadable new cheese formulation was developed to increase the edibility and nutritional value of traditional Tort cheese. In this context, pulp (carob molasses pulp (CMP)) from carob molasses production was added to the cheese in different proportions (5%, 10%, and 15%), and some physicochemical, textural, and sensory properties of the cheeses were examined. As a result of the research, it was determined that the addition of CMP caused a decrease in the pH, fat, and protein content of the cheeses, while significantly increasing the dry matter, acidity, ash, carbohydrate, antioxidant activity, and total phenolic content. With CMP addition, the hardness and water-holding capacity of the cheeses increased, while spreadability, adhesiveness, and syneresis decreased. As the concentration of CMP increased, the L* and b* values decreased, while the a* value increased. In terms of sensory properties, the least preferred sample was the control, while the sample with 5% CMP addition, which is the most spreadable cheese, was the most preferred. As a result, a new product with lower fat content that was more durable and stable, rich in bioactive properties, and with improved sensory attributes was developed.

Exploiting the Potential of Powdered Blends of Recovered Sunflower Seed Cake Phenolics and Whey-Development of Sustainable Food Additives.

The management of side streams from the food industry, especially oil and dairy by-products, has become an important issue linked to the European Commission's recommendations for a circular economy. This study aimed to obtain sustainable food additives in the form of soluble-type powders composed of whey and recovered phenolics originating from sunflower seed cake. In order to valorise these di-blend products, the powders were characterised in terms of their physical, chemical, and sensory attributes. Based on the study findings, the addition of sunflower seed cake washouts (SSCWs) to whey (Wh) decreased the dry matter in the feed that affected the viscosity and drying yield. The addition of SSCWs did not have a significant effect on the physical properties of powders, except for colour. By-product management proposed in the study resulted in the production of nutritious and ready-to-use products in powder form with improved functional properties in terms of phenolic compounds and antioxidant capacity. The powders were sensorially appealing with a tangy sourness entwined with a delicate interplay of sweet and salty flavours, which can be easily incorporated into different types of foodstuffs.

Impact of Novel Functional Ingredients on Lactobacillus casei Viability

Nipple fruit (Solanum mammosum), teosinte (Dioon mejiae), Caesar mushroom (Amanita caesarea), and weevil (Rhynchophorus palmarum) powders have shown great nutritional content with meaningful dietary applications. This study aspired to investigate the impact of nipple fruit, teosinte, Caesar mushroom, and weevil powders on the bile tolerance, acid tolerance, lysozyme tolerance, gastric juice resistance, and protease activity of Lactobacillus casei. Nipple fruit, teosinte, Caesar mushroom, and weevil powders were combined at 2% (wt/vol), whereas the control samples did not include the ingredients. The bile and acid tolerances were analyzed in Difco De Man–Rogosa–Sharpe broth incubated under aerobic conditions at 37 °C. The bile tolerance was investigated by adding 0.3% oxgall, whereas the acid tolerance was studied by modifying the pH to 2.0. The lysozyme tolerance was studied in electrolyte solution containing lysozyme (100 mg/L), while the gastric juice tolerance was analyzed at pH levels of 2, 3, 4, 5, and 7. The protease activity was studied spectrophotometrically at 340 nm in skim milk incubated under aerobic conditions at 37 °C. The results show that nipple fruit increased the counts, whereas Caesar mushroom and weevil powders resulted in lower counts for bile tolerance, acid tolerance, lysozyme resistance, and simulated gastric juice tolerance characteristics. Furthermore, the protease activity increased by adding nipple fruit to skim milk. According to the results, nipple fruit may improve the characteristics of L. casei in cultured dairy by-products.

Innovative applications of whey protein for sustainable dairy industry: Environmental and technological perspectives-A comprehensive review.

Industrial waste management is critical to maintaining environmental sustainability. The dairy industry (DI), as one of the major consumers of freshwater, generates substantial whey dairy effluent, which is notably rich in organic matter and thus a significant pollutant. The effluent represents environmental risks due to its high biological and chemical oxygen demands. Today, stringent government regulations, environmental laws, and heightened consumer health awareness are compelling industries to responsibly manage and reuse whey waste. Therefore, this study investigates sustainable solutions for efficiently utilizing DI waste. Employing a systematic review approach, the research reveals that innovative technologies enable the creation of renewable, high-quality, value-added food products from dairy byproducts. These innovations offer promising sustainable waste management strategies for the dairy sector, aligning with economic interests. The main objectives of the study deal with, (a) assessing the environmental impact of dairy sector waste, (b) exploring the multifaceted nutritional and health benefits inherent in cheese whey, and (c) investigating diverse biotechnological approaches to fashion value-added, eco-friendly dairy whey-based products for potential integration into various food products, and thus fostering economic sustainability. Finally, the implications of this work span theoretical considerations, practical applications, and outline future research pathways crucial for advancing the sustainable management of dairy waste.

Recycling of animal protein wastes in the formulation of feed for Labeo rohita and Mystus vittatus—a comparative evaluation

Lactic acid bacteria (LAB) are key players in the fermentation of organic wastes and their recycling as feedstuff for fish. Whey, a common dairy byproduct in India, is a cheap source of LAB and can be used to ferment animal byproducts. An experimental study was designed to explore whether the whey fermented animal protein blend (WFAPB) could be used as a fishmeal replacer in the formulation of feed for both stomach-less carp fish Labeo rohita and stomach-bearing catfish Mystus vittatus. Experiments were performed with five isoproteinous, isolipidous, and isoenergetic feeds with WFAPB replacing fishmeal (FM) by 0% (T1), 25% (T2), 50% (T3), 75% (T4), and 100% (T5). Fifteen days of laboratory experiments with these experimental feeds revealed that more than 50% FM replacement level could result in excess postprandial absorption (6 h) of some essential and non-essential amino acids in the plasma of both fish. The postprandial absorption was more in M. vittatus than L. rohita. Ninety-day experiments were conducted in outdoor cement vats to measure growths and deposition of amino acids (AA) in muscle. Regression analysis was performed to find the optimal FM replacement based on four growth parameters and fifteen AA deposition in muscle. A two-phase fuzzy methodology was used to obtain Pareto-optimal replacement levels for each fish. The results demonstrated that FM replacement levels were 7.63% and 36.79% respectively for L. rohita and M. vittatus when only four growth parameters were considered. However, based on the FM replacement level that maximized deposition of 15 amino acids and growth parameters, it was found that 12.23% and 40.02% replacement of FM by the WFAPB was ideal respectively for L. rohita and M. vittatus. The results revealed that only a fraction of both essential and non-essential amino acids absorbed in plasma could be converted into protein and deposited as bound amino acids in the muscle. It is concluded that fermentation by whey is an inexpensive, easily available, and environmentally sustainable technique to recycle animal protein in the formulation of feed for fish, and the stomach-bearing carnivorous fish are more efficient in utilizing fermented animal protein blend than the stomach-less carps.

Food Safety Assessment and Nutraceutical Outcomes of Dairy By-Products: Ovine Milk Whey as Wound Repair Enhancer on Injured Human Primary Gingival Fibroblasts.

The valorization of milk whey appears to be a promising strategy for managing by-products from dairy food industries, which incur demanding economic costs for treatment and/or disposal. Thanks to its numerous bioactive components, whey is expected to be increasingly incorporated into foods in the future. We investigated the safety of ovine milk whey through in vitro experiments on human primary gingival fibroblast (HGF-1) proliferation and wound healing. Fibroblasts play a crucial role in the repair processes from the late inflammatory phase until the final stages. Cells treated with varying concentrations of ovine whey (0.01%, 0.1%, 1%, and 10%) were able to close wounds more rapidly than vehicle-treated cells. Time- and dose-dependent responses were observed in cell populations exposed to ovine whey. Specifically, wounds treated with 0.1% and 10% milk whey showed better migratory capabilities compared to those treated with 0.01% and 1% milk whey after 24 and 48 h. In addition, ovine milk whey stimulates extracellular matrix deposition, as evidenced by the increasing levels of CD44 antigen density evaluated through FACS analysis, as well as COL1A1 expression measured both via RT-qPCR and immunofluorescence. This phenomenon was particularly evident at concentrations of 0.01% and 10%. Ensuring quality and safety has become a major concern for health authorities in the food industry. Our findings suggest that ovine milk whey is safe and possesses regenerative properties. It facilitates tissue re-establishment following exposure to environmental stress, particularly accelerating gingival wound closure.

Hybrid Amyloid-Chitin Nanofibrils for Magnetic and Catalytic Aerogels.

In the quest for a sustainable and circular economy, it is essential to explore environmentally friendly alternatives to traditional petroleum-based materials. A promising pathway toward this goal lies in the leveraging of biopolymers derived from food waste, such as proteins and polysaccharides, to develop advanced sustainable materials. Here, we design versatile hybrid materials by hybridizing amyloid nanofibrils derived by self-assembly of whey, a dairy byproduct, with chitin nanofibrils exfoliated from the two distinct allomorphs of α-chitin and β-chitin, extracted from seafood waste. Various hydrogels and aerogels were developed via the hybridization and reassembly of these biopolymeric nanobuilding blocks, and they were further magnetized upon biomineralization with iron nanoparticles. The pH-phase diagram highlights the significant role of electrostatic interactions in gel formation, between positively charged amyloid fibrils and negatively charged chitin nanofibrils. Hybrid magnetic aerogels exhibit a ferromagnetic response characterized by a low coercivity (<50 Oe) and a high specific magnetization (>40 emu/g) at all temperatures, making them particularly suitable for superparamagnetic applications. Additionally, these aerogels exhibit a distinct magnetic transition, featuring a higher blocking temperature (200 K) compared to previously reported similar nanoparticles (160 K), indicating enhanced magnetic stability at elevated temperatures. Finally, we demonstrate the practical application of these hybrid magnetic materials as catalysts for carbon monoxide oxidation, showcasing their potential in environmental pollution control and highlighting their versatility as catalyst supports.

Antirotaviral activity of dairy byproducts enriched in fractions from hyperimmune bovine colostrum: the effect of thermal and high hydrostatic pressure treatments.

Nowadays, rotaviruses remain a major health burden, especially in developing countries, and strategies complementary to vaccination are needed. In this view, dairy fractions have attracted great scientific interest, due to their high content of bioactive compounds. The objective of this study was to evaluate the antiviral activity of whey and buttermilk enriched in proteins from hyperimmune bovine colostrum (HBC) against rotavirus. The enriched fractions were spray-dried and subsequently tested for their neutralizing activity against the bovine rotavirus WC3 strain in vitro, using differentiated Caco-2/TC7 cells. The highest antirotaviral activity was observed when whey and buttermilk were enriched in purified immunoglobulin G (IgG), showing complete rotavirus neutralization at concentrations of 3 and 6 mg mL-1 for whey and buttermilk, respectively. Additionally, the use of a crude immunoglobulin fraction also gave satisfactory results. The inhibitory activities of all samples significantly decreased after the application of heat, except for the IgG-enriched buttermilk which showed a slight increase of activity following the application of short-time treatments (75 or 85 °C for 20 s). This sample also showed a significant increase of activity (13%) after the application of low-intensity high hydrostatic pressure treatment (400 MPa for 5 min). The maximum loss of bioactivity was observed at 600 MPa for 10 min (31 and 20% for whey- and buttermilk-based formulas, respectively). This study provides relevant information on the potential of whey, buttermilk, and HBC to be part of functional products as complementary strategies to combat rotavirus infections.

Sicilian Whey: Utilization of Ricotta Whey in the Production of Value-Added Artisanal Beers

Scotta is an underutilized whey by-product of ricotta making. In this study, we investigated the utilization of scotta in beer production. To understand the quality of regional scotta, samples from eight Sicilian ricotta makers were analyzed for pH, total protein, fat, lactose, titratable acidity, % salt, total plate count, lactic acid bacteria counts, and minerals. Overall, the samples had low amounts of residual protein and fat. The average lactose content was 4.81 g/100 mL ± 0.52 g, with a pH of 6.12 ± 0.17 and a salt content of 1.05% ± 0.24. The majority of lactic acid bacteria counts were below the limit of detection. The total plate counts were more variable, ranging between 102 to 103 CFU/mL, suggesting occasional post-processing contamination during handling. Scotta was then used to replace some of the water and sugar in the production of two beer styles: (i) a Gose, a salty and acidified German beer style, and (ii) a sweet milk stout. A trained panel used for sensory analysis found that these prototypes fit within the sensory profiles of commercial beers of these styles. This work highlights opportunities to upcycle dairy by-products into novel fermented beverages that would be appealing to consumers.

Carriers based on dairy by-products and dehumidified-air spray drying as a novel multiple approach towards improved retention of phenolics in powders: sour cherry juice concentrate case study.

Sour cherry juice concentrate powder can serve as a modern, easy-to-handle, phenolics-rich merchandise; however, its transformation into powdered form requires the addition of carriers. In line with the latest trends in food technology, this study valorizes the use of dairy by-products (whey protein concentrate, whey, buttermilk, and mixes with maltodextrin) as carriers. A new multiple approach for higher drying yield, phenolics retention (phenolic acids, flavonols and anthocyanins) and antioxidant capacity of powders were tested as an effect of simultaneous decrease of drying temperature due to the drying air dehumidification and lower carrier content. Dairy-based carriers were effective for spray drying of sour cherry-juice concentrate. The drying yield was increased and retention of phenolics was higher when compared with maltodextrin. The application of dehumidified air, which enabled the drying temperature to be reduced, affected drying yield positively, and also affected particle morphology and retention of phenolics (the phenolic content was approximately 30% higher than with spray drying). The study proved that it is possible to apply dairy-based by-products to produce sour cherry juice concentrate powders profitably, lowering the spray-drying temperature and changing the carrier content. Dehumidified air spray drying can be recommended for the production of fruit juice concentrate powders with improved physicochemical properties. © 2023 Society of Chemical Industry.

Valorization of Different Dairy By-Products to Produce a Functional Dairy–Millet Beverage Fermented with Lactobacillus paracasei as an Adjunct Culture

Fermented dairy products not only have a long shelf-life but also have beneficial nutritional values. The products are deficient in dietary fiber and certain bioactive compounds. Adding grains to dairy products is a widespread practice to improve the nutritional and economic aspects. In this work, we studied the effect of fermented millet–milk beverages (FMBs) using pearl millet grains and three different dairy by-products (sweet whey, sweet buttermilk, and skimmed milk). A control treatment prepared with water was also manufactured for comparison. Samples were continuously prepared and fermented using a commercial yogurt starter culture (YC-381) containing L. delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and a pure strain of L. paracasei subsp. Paracasei. Four FMBs (water based: WB-FMB, whey based: WHB-FMB, buttermilk based: BMB-FMB, and skimmed milk based: SMB-FMB) were analyzed during cold storage at 4 °C for up to 15 days for chemical, microbiological properties, minerals content, antioxidant properties, glycemic index, and glycemic load on days 1, 8, and 15. The sensory characteristics of the FMBs were also evaluated during cold storage (4 °C/15 days). In general, the progression of acidity was slower in SMB-FMB and WHB-FMB samples during fermentation compared to in the BMB-FMB sample. The longest fermentation time was for the SMB-FBM sample (3 h), while the shortest was for the BMB-FMB sample (1.5 h). Reflecting the good manufacturing practices, all samples were free of coliform, mold, and yeast. No bacterial growth was detected in the WB-FMB sample at days 8 and 15 of storage, while the growth of Lactobacillus spp. and S. thermophilus was significantly higher (9.97 ± 0.01 and 9.48 ± 0.06, respectively) in the BMB-FMB sample compared to in the other three FMBs. The FMBs produced using dairy by-products had more antioxidant properties. All samples were better perceived during sensory evaluation by panelists than the water-based sample, except for the BMB-FMB sample, in which a bitter taste appeared. In the BMB-FMB sample, the proteolytic degree was significantly higher (4.8 ± 0.09) after 3 h of fermentation by about 460% than in the fresh sample. All samples had a low glycemic index and glycemic load. In addition, acidity progression was slower in SMB-FMB and WHB-FMB samples during fermentation and storage compared to the WB-FMB sample. Therefore, it could be recommended that it is more beneficial to prepare fermented millet–milk beverages using dairy by-products and suitable starter cultures under optimal fermentation conditions instead of using water to maximize the nutritional and economic aspects.

Optimization of a production unit of the dairy agroin-dustry: Chapingo dairy technology unit case

Objective: To evaluate the optimization level of a dairy production unit (DPU) through a mathematical programming model (MP). It is expected that by maximizing net income by at least 10%, the DPU will be more profitable than without optimized management. Design/Methodology/Approach: The analysis was carried out under the economic approach of agricultural production, taking into consideration 11 decision variables in the objective function (OF), which was subject to 20 constraints. The variables were based on the requirements of the demand for dairy by-products, using technical coefficients (input-output coefficient). Excel® Solver® was used to develop the sensitivity report and to analyze the shadow prices and reduced costs. Results: Three scenarios were modeled. Between the first and third scenario, the income increased to $58,000.00 (41.02%). Between the second and third scenario, the income increased to $63,840.00 (46.16%). Study Limitations/Implications: Dairy food processing is an important industry in the economies of the world. Findings/Conclusions: Panela cheese recorded the highest shadow price ($72.85), which indicates that the DPU should concentrate on this type of dairy product. In conclusion, the optimization of the DPU guarantees the efficient use of scarce resources and therefore generates a higher profit.