This study aimed to review hazard analysis and critical control points (HACCP) in the dairy industry for the production of yogurt. The food safety management system (FSMS) was implemented over the last several decades with several amendments. The need for practical and proactive procedures in the dairy industry was identified so that HACCP implementation could ensure that consumers would always have safe food. The concept of HACCP is a systemic and science-based method that can result in safe dairy products such as yogurt based on the complete analysis of manufacturing processes, recognition of hazards potentially present at all stages of production, and risk prevention. In yogurt production, raw milk receipt, pasteurization, packaging, and storage are the steps most susceptible to contamination and were considered critical control points. Further steps also need to be implemented to achieve other related control measures, and these will be discussed.

We investigated sonication as a pre-processing step to reduce acid whey generation during Greek yoghurt manufacture. The generation of a large amount of acid whey during the production of Greek yoghurt is an ongoing problem in the dairy industry and many studies are currently focusing on reducing it. We focused on the use of ultrasonication as a novel approach to minimize the casein fraction in the acid whey stream and simultaneously improve the gel properties. Ultrasound applied before the fermentation modified the structural properties and bonding behaviours of milk proteins, and enhanced the retention of casein in the yoghurt gel after the fermentation and straining steps. Therefore, the use of low-frequency ultrasonication as a pre-processing step may have the potential to provide significant economic benefits to the Greek yoghurt manufacturing process. Moreover, it improved the nutritional and physicochemical properties compared to regular Greek yoghurts.

Greek yogurt is one of the fastest growing products in the dairy industry. It is also known as strained yogurt, which is obtained after draining the whey. As a result of the draining process, Greek yogurt has higher total solids and lower lactose than regular yogurt. Since it is a concentrated yogurt, its sensory characteristics are different from regular yogurt. However, there is little information about factors influencing the quality of Greek yogurt and sensory evaluation techniques applied to Greek yogurt. This review aims to describe the effects of ingredients, starter cultures, processing techniques and other parameters on quality characteristics and sensory properties of Greek yogurt. In addition, advantages and limitations of novel sensory evaluation techniques applied to Greek yogurt products are discussed. In particular, we take a look at advanced techniques such as the electronic nose and electronic tongue and the benefits of these techniques with regard to Greek yogurt. This review should help the Greek yogurt industry to improve its current products and develop innovative products based on appropriate food evaluation techniques.

This study examined the effects of fat content (0.1%, 1.5%, 3%, and 3.5%), heat treatment (pasteurization and UHT), and vitamin D supplementation on the physicochemical, microbiological, and sensory characteristics of yoghurt over 21 days. Yoghurts with higher fat content generally received higher sensory acceptability scores (7–8), exhibited less syneresis (14.75–22.48%) and higher whiteness index; 0.1%-fat had the highest syneresis (51.28%) and lowest whiteness (80.77) (p < 0.05). Although pasteurised yoghurt exhibited slightly better firmness (1.77 N) than UHT (1.61 N), no significant effect of heat treatment was found (p > 0.05). Sensory preference was for 3% and 3.5%-fat and pasteurised variety, especially for consistency. All yoghurts maintained viable lactic acid bacteria counts >10⁷ cfu/g throughout the storage period. The vitamin D addition resulted in a 6% average higher syneresis rate (p > 0.05) and a nearly 4% higher whiteness index (p < 0.05). This study shows that it is possible to obtain yoghurts with enhanced properties by optimizing the fat content and heat treatment conditions applied, and it also directs future studies on the effect of vitamin D addition on yoghurt properties.

In this research communication we describe an innovative protocol that combines three pairs of primers, two from the literature and one designed in our laboratory, for application in triplex-PCR on somatic cell DNA to enable identification of the species origin (cow, sheep, goat) of cheeses and yogurts with a detection limit of 0.1%. Mislabeling was detected in 15 out of 40 cheeses and in 18 out of 40 yogurts tested. The suggested procedure is a quick and reliable tool for identifying the animal origin of cheeses and yogurts and it can be used to certify product reliability on the domestic and international market. Additionally, in combination with a serological test it can offer a reliable tool for detecting the presence of cow's whey.

This study explores Turkish yoghurt varieties, emphasizing their cultural significance, historical roots, and regional diversity. Traditionally made with animal- and plant-based coagulants, Turkish yoghurt has evolved from its origins in Central Asia and the Ottoman Empire into a dynamic industry. Variations are classified by texture, fat content, and flavour, shaped by Türkiye's geographical diversity. Unique regional types exhibit distinct sensory and nutritional traits. The study also highlights the integration of traditional methods into modern production, ensuring the preservation and innovation of Turkish yoghurt in today's markets. Turkish yoghurt varieties have rich diversity and cultural significance, offering valuable insights into the gastronomy field. The findings emphasize the unique sensory and nutritional characteristics of regional yoghurts, which can inspire innovative culinary applications. For instance, chefs and product developers can incorporate traditional yoghurts like Antakya Salted Yoghurt or Tavas Smoked Sheep Yoghurt into modern recipes, creating novel dishes that balance authenticity and creativity. The study also sheds light on the potential of yoghurt-based products such as ayran and keş to serve as sustainable and nutritious alternatives in contemporary gastronomy. Additionally, understanding traditional production methods opens avenues for preserving and reviving artisanal techniques, fostering a deeper appreciation for local food heritage. By bridging tradition and innovation, this research contributes to the development of gastronomy as both an art and a science, enhancing the global visibility of Turkish cuisine.

Set yogurt's physical characteristics are greatly affected by the homogenization and heat treatment processes. In our previous study, set yogurt treated at 130°C and with the fat particle size reduced to ≤0.6 μm had equivalent curd strength, less syneresis and smoother texture than yogurt treated at 95°C. When investigating the mechanisms underlying yogurt's physical properties, it is important to evaluate the yogurt's microstructure. We conducted electron microscopy evaluations to investigate the mechanisms of changes in yogurt's physical properties caused by 130°C heat treatment and by a reduction in the fat globule size. We prepared yogurt mixtures by combining heat treatment at 95 and 130°C and homogenization pressure at 10 + 5 and 35 + 5 MPa and then fermented the mixtures in a common yogurt starter. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for the structural observations. Fine particles were observed on the surface of the casein micelles of the yogurt treated at 95°C, and the coalescence density between micelles was high. The surface of the yogurt treated at 130°C had few fine particles, and the coalescence density between micelles was low. The yogurt treated at 130°C with 35 + 5 MPa homogenization had low coalescence density between casein micelles, but smaller-particle-size fat globules increased the network density. Approximately 30% of the fat globules were estimated to be incorporated into the yogurt networks compared to the volume of casein micelles. We speculate that 130°C heat treatment alters the structure of whey protein on the surface of casein micelles and interferes with network formation, but reducing the size of fat globules reinforces the network as a pseudoprotein.

In this research communication we describe a straightforward triplex-PCR protocol able to differentiate the origin of milk from three closely related species (goat, sheep and cow) in Halloumi, a cheese with Protected Designation of Origin (PDO), and yogurts. Halloumi must contain at least 51% sheep or goat milk, therefore, the fraudulent adulteration of this cheese with excess of cow milk must be routinely tested. The assay employs one universal forward primer and three species-specific reverse primers giving rise to 287 bp (cow), 313 bp (goat), and 336 bp (sheep) amplicons, under the same amplification conditions. This protocol, when used to test a small number of Cyprus commercial products, correctly detected mislabeling in Halloumi (2 out of 6 samples were adulterated) and yogurt brands (1 out of 4 was adulterated). The suggested protocol is a reliable tool for identifying the origin of milk in Halloumi cheeses and yogurts and can be used in any laboratory equipped with a thermocycler and an agarose gel electrophoresis apparatus.

The aim of this review was to present various topics related to lactose intolerance with special attention given to the role of fermented foods and probiotics in alleviating gastrointestinal symptoms. Lactose intolerance is a common digestive problem in which the human body is unable to digest lactose, known as milk sugar. Lactose intolerance can either be hereditary or a consequence of intestinal diseases. Recent work has demonstrated that fermented dairy products and probiotics can modify the metabolic activities of colonic microbiota and may alleviate the symptoms of lactose intolerance. We suggest that, lactose free dairy products could be recommended as alternatives for the alleviation of lactose intolerance and for the promotion of human health and wellness.

Yogurt acid whey (YAW) contains significant amounts of calcium as well as small amounts of protein, thus the idea of its reintroduction, especially of its calcium content, to the food chain is attractive. Calcium in milk is mainly complexed with casein micelles, whereas YAW contains only small amounts of protein, with no caseins at all, differing substantially from milk in the form in which calcium occurs. Therefore, the objective of the present research paper was to evaluate whether calcium bioavailability differs between YAW and milk. Following the INFOGEST protocol for simulated digestion and by coupling it with the Caco-2 model for intestinal absorption, calcium in YAW had higher bioaccessibility than calcium in milk. However, there were no differences in calcium transport by the intestinal cells and the transcription level of calcium absorption-related genes (VDR, TRPV6, S100G and PMCA1). Lastly, there were no differences in calcium bioaccessibility and the transcription of the calcium absorption-related genes between YAW samples of bovine, ovine or caprine origin obtained from Greek dairy products enterprises. In conclusion, despite the major differences in the protein profile between YAW and milk, there were no differences in calcium transport by the cells, but YAW was associated with higher calcium bioaccessibility, which ultimately may result in higher amount of absorbed calcium.

This research paper assessed textural, microstructural, sensory and colour properties of set-yoghurts produced using milk from two indigenous cattle types, Thamankaduwa White (TW) and Lankan cattle (LC) compared to two generic cattle breeds, Friesian and Jersey. Instrumental texture profile (firmness, adhesiveness, cohesiveness and springiness), colour space (L* a* b*) and scanning electron micrographs of set-yoghurts during 21 d of storage (4 ± 1°C) were evaluated. Sensory quality attributes were evaluated with 40 untrained panellists using a five-point hedonic scale. Set-yoghurts prepared using indigenous cow milk showed higher (P < 0.05) firmness, cohesiveness and apparent viscosity values compared to those prepared using generic cow milk. As revealed by micrographs, set-yoghurts made from TW milk had lesser and smaller void spaces and a dense protein gel network than gels made from LC and the two generic breeds. The gel network made from Friesian milk showed a comparatively larger porous gel structure and thinner protein strands resulting in a weaker gel than other milk gels. The highest lightness (L*) and yellowness (b*) were observed from set-yoghurt produced from Friesian and LC milk, respectively. Set-yoghurts from TW milk had the highest (P < 0.05) sensory scores for all sensory attributes. The lowest sensory acceptance was recorded in set-yoghurt made from Friesian milk. Thus, milk from TW and LC is likely to be suitable in producing set-yoghurts with superior textural, microstructural and sensory properties, compared to milk from Jersey and Friesian. Our results suggest the merits of using indigenous cow milk in producing set-yoghurts and, thereby, prioritizing the preservation of the genetic pool of these indigenous breeds.

Nonfat set yogurts are very popular in Japan because of their health properties, but have the disadvantage of being hard and having large curd particles compared to fat-containing yogurts. We investigated the effect of lactose hydrolysis on nonfat set yogurt to determine whether this technique can improve the sensory evaluation and the texture of a nonfat set yogurt. We prepared nonfat yogurt mixes with 0, 50, 75, and 100% lactose hydrolysis and fermented them. The sensory properties, physical properties, fermentation characteristics, extracellular polysaccharide (EPS) concentration and lactic acid bacteria count were then assessed. The results demonstrated that the lactose hydrolysis rate had no effect on the fermentation time. The 75% lactose hydrolysis increased the EPS concentration and inhibited post-acidification. The 100% lactose hydrolysis increased the number of Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) and further increased the EPS concentration, and despite the increase in the number of L. bulgaricus, the 100% lactose hydrolysis suppressed post-acidification. The results of a sensory evaluation showed that the 100% lactose hydrolysis increased the yogurt's viscosity and overall acceptability and suppressed its acidity. The physical-properties evaluation revealed that when the lactose hydrolysis rate was ≥75%, the curd hardness decreased, and the curd particles became smaller. We inferred that these sensory and physical changes originated from an increase in the EPS concentration, and we thus speculate that a 100% lactose hydrolysis rate before fermentation would be a useful means of solving the hardness and large curd particles of nonfat set yogurt.

This research paper focuses on enrichment of yoghurt containing probiotic Lactobacillus casei with persimmon (Diospyros kaki) powder in concentrations of 0 (Control) and then 0.5, 1.0, 1.5 and 2.0% (A–D respectively) and determination of some characteristics of the product during refrigerated storage for 21 d. Powder addition affected the color characteristics, textural properties, titratable acidity and water-holding capacity values. The viability of both yoghurt bacteria (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus) and L. casei increased proportionally to adding persimmon powder for all storage days. Furthermore, addition of fruit powder increased short-chain fatty acid and polyunsaturated fatty acid contents. According to sensory analysis results, sample D had the lowest scores from the panelists, whereas the Control together with samples B and C were the most liked yoghurts in terms of flavor characteristics. In terms of overall acceptability, all of the samples received scores over three points on a five-point scale throughout storage. This study indicates that persimmon powder enriched yoghurt is a good vehicle for L. casei and yoghurt bacteria with improved fatty acid profile and acceptable sensory characteristics.

Scientific studies demonstrate the importance of intestinal microbiota to human health and how probiotic microorganisms can positively affect health when administered regularly and in adequate amounts. Probiotic bacteria can be part of fermented products and their functional importance is associated mainly with their metabolism. They are thought to benefit individuals to maintain their health and also to strengthen resistance against various types of diseases. The acceptance of probiotic cultures and products by consumers increased when these bacteria were marketed as natural cultures that help in digestion and health. Considering this, the food industry has an increasing demand for new candidates as probiotic cultures, and the dairy industry has a particular interest for fermented milks and other dairy products, since these are the most common food vehicles for probiotic cultures. Therefore, the dairy industries are increasingly seeking to improve their products with these beneficial bacteria. However, the legal peculiarities and excess of control agencies in Brazil makes the registration of these products and the collection of data very complex. Prospective analysis suggests that probiotic foods have the potential to effect a considerable expansion of the dairy industry, allowing the dairy sector to grow and for these products to be increasingly sought by consumers globally. For this, not only actions on research and innovation are necessary, but also official clarifications on the claims for considerations of microbiological security and functionality of these products. This review aims to elucidate important probiotic research regarding the isolation and characterization of beneficial cultures in Brazil, and to demonstrate the relevance of the dairy chain as a potential source of novel cultures for the development of new probiotic products to expand the Brazilian dairy industry.

We assessed the chemical, microbiological, rheological and sensory parameters of a fermented dairy product (FDP) containing a galactooligosaccharide (GOS) preparation. This was made from a solution of dried whey and skim milk containing 25% (w/w) lactose using a new enzyme with high transgalactosylation activity (Nurica: Danisco A/S). Conversion of the high initial lactose content enabled a good yield of 56% GOS to be achieved. The obtained GOS preparation was applied to the FDP with a probiotic culture of Bifidobacterium animalis ssp. lactis in amounts of 0, 2, 10, and 20% (w/w). The FDPs were stored and monitored for 9 weeks. Bifidobacteria showed counts higher than 106 CFU/g throughout the storage period. GOS were not significantly utilized during fermentation and their changes during storage were also insignificant. Gel strength after fermentation showed a slight decrease with increasing doses of GOS preparation, but after 6 weeks of storage, the differences were no longer evident. The sensory analysis revealed the overall acceptability of the prepared FDPs, whilst the highest dose (20% GOS preparation) led to a sweeter taste.

This research aimed to analyse the influence of Apis mellifera intermissa honey supplementation on the technological, physicochemical, microbiological and sensory characteristics of stirred goat yoghurt containing Lactiplantibacillus plantarum C78, a novel probiotic strain, during 28 days of refrigerated storage. Four formulations of yoghurt were prepared, with different honey contents (0.5 %, 10 % and 15 %), and all samples were inoculated with the probiotic strain. The colour, syneresis (52.45 ± 0.19%), viscosity (28 ± 0.25 Pa.s) and sensory acceptance were improved in samples having 15% honey. The viability of L. plantarum C78 in all yoghurt samples presented counts above 7 log CFU/mL until the day-28 of refrigerated storage and honey increased the count of probiotic culture to 8.5 and 8.7 log CFU/mL at day-14 and day-21 of storage. These results reveal a successful incorporation of both probiotic and honey and promote the nutritional and sensory properties of the new yoghurt formulation.