Enrichment Of Cheese Research Articles

Biological Enrichment of Cheese

Biological Enrichment of Cheese

Characteristics of Unripened Cow Milk Curd Cheese Enriched with Raspberry (Rubus idaeus), Blueberry (Vaccinium myrtillus) and Elderberry (Sambucus nigra) Industry By-Products.

The aim of this study was to apply raspberry (Ras), blueberry (Blu) and elderberry (Eld) industry by-products (BIB) for unripened cow milk curd cheese (U-CC) enrichment. Firstly, antimicrobial properties of the BIBs were tested, and the effects of the immobilization in agar technology on BIB properties were evaluated. Further, non-immobilized (NI) and agar-immobilized (AI) BIBs were applied for U-CC enrichment, and their influence on U-CC parameters were analyzed. It was established that the tested BIBs possess desirable antimicrobial (raspberry BIB inhibited 7 out of 10 tested pathogens) and antioxidant activities (the highest total phenolic compounds (TPC) content was displayed by NI elderberry BIB 143.6 mg GAE/100 g). The addition of BIBs to U-CC increased TPC content and DPPH- (2,2-diphenyl-1-picrylhydrazyl)-radical scavenging activity of the U-CC (the highest TPC content was found in C-RaNI 184.5 mg/100 g, and strong positive correlation between TPC and DPPH- of the U-CC was found, r = 0.658). The predominant fatty acid group in U-CC was saturated fatty acids (SFA); however, the lowest content of SFA was unfolded in C-EldAI samples (in comparison with C, on average, by 1.6 times lower). The highest biogenic amine content was attained in C-EldAI (104.1 mg/kg). In total, 43 volatile compounds (VC) were identified in U-CC, and, in all cases, a broader spectrum of VCs was observed in U-CC enriched with BIBs. After 10 days of storage, the highest enterobacteria number was in C-BluNI (1.88 log10 CFU/g). All U-CC showed similar overall acceptability (on average, 8.34 points); however, the highest intensity of the emotion "happy" was expressed by testing C-EldNI. Finally, the BIBs are prospective ingredients for U-CC enrichment in a sustainable manner and improved nutritional traits.

Linoleic acid enrichment of cheese by okara flour and Geotrichum candidum overexpressing Δ12 fatty acid desaturase.

Mold-ripened cheeses have low levels of unsaturated fatty acids (UFAs). Geotrichum candidum is an adjunct culture for the development of Geotrichum-ripened cheese but has a low ability to produce high levels of UFAs. Δ12 fatty acid desaturase (FADS12) is a pivotal enzyme that converts oleic acid (OA) to linoleic acid (LA) and plays a vital role in UFA biosynthesis. By investigating FADS12 catalytic activity from various species with OA substrates, we found that FADS12 from Mucor circinelloides (McFADS12) had the highest catalytic activity for OA. In the current study, a plasmid harboring McFADS12 was constructed and overexpressed in G. candidum. Our results showed that LA production increased to 31.1 ± 1.4% in engineered G. candidum - three times higher than that in wild-type G. candidum. To enhance LA production, an exogenous substrate (OA) was supplemented, and the yield of LA was increased to 154 ± 6 mg L-1 in engineered G. candidum. Engineered G. candidum was used as an adjunct culture for Geotrichum-ripened cheese production. The LA level reached 74.3 ± 5.4 g kg-1 cheese, whereas the level of saturated fatty acids (SFAs) decreased by 9.9 ± 0.5%. In addition, the soybean byproduct (okara) was introduced into the engineered G. candidum growth and the level of LA increased to 126 ± 4 g kg-1 cheese and the percentage of UFAs:SFAs increased from 0.8:1 to 1.3:1. This study offers a suitable technology for converting SFAs to UFAs in Geotrichum-ripened cheeses and provides a novel trend for converting soybean waste into a value-added product. © 2022 Society of Chemical Industry.

Feeding Dairy Ewes with Fresh or Dehydrated Sulla (Sulla coronarium L.) Forage. 2. Effects on Cheese Enrichment in Bioactive Molecules.

Simple SummaryFeeding ruminants with fresh sulla forage, containing polyphenols with antioxidant activity, seems to improve the performance of animals and the technological, nutritional and health properties of dairy products. However, the potential of sulla forage can be compromised by traditional methods, such as hay-making, to produce conserved forage; alternatively, dehydration could be an appropriate solution to preserve the content in bioactive components. This paper reports the effects of feeding dehydrated or fresh sulla forage on physico-chemical traits and health properties, due to antioxidant activity and fatty acid profile, of sheep cheese. An attempt was made also to identify cheese constituents that, being able to discriminate the ewes’ diet, may be proposed as biomarkers to trace cheese produced from animals fed with fresh forage. The results showed that the use of fresh or dehydrated sulla was able to enhance the health properties of cheeses, so dehydration can represent an opportunity to preserve the potential of fresh sulla forage. Moreover, α-linolenic acid and its ratio with linoleic acid showed the ability to discriminate cheese in relation to the animals’ feeding regime.Sulla is a tanniferous legume species largely used as fresh or preserved forage in the ruminants’ diets. Due to its content in polyphenols with antioxidant activity, especially condensed tannins (CT), fresh sulla forage (FSF), when eaten by ruminants, is able to enrich animal products with antioxidant molecules and polyunsaturated fatty acids (PUFA) that are beneficial for consumers’ health. Dehydration represents a valid alternative to haymaking to preserve these properties also in periods when FSF is unavailable. In this research, the effects of ewes’ diets based on sulla hay (SH), pelleted dehydrated sulla forage (DSF) or FSF were evaluated on cheese physico-chemical traits, including fatty acid (FA) profile, vitamins A and E, polyphenols, antioxidant capacity and oxidative stability. The individual daily milk from 10 first lambing (FL) and 10 third lambing (TL) Valle del Belìce ewes at about 60 days in milk, divided homogeneously into 5 groups fed different diets in a partial 5 × 2 Latin square design with 2 phases, and the bulk milk of farming ewes fed only on natural pasture, were used in 2 sessions of micro cheese-making to manufacture cheeses, sampled at 48 h of ripening. The experimental diets were: SHL = SH ad libitum; DSF2 = 2 kg/day DSF per head plus SH ad libitum; FSF2 = 2 kg/day FSF per head plus SH ad libitum; FSF4 = 4 kg/day FSF per head plus SH ad libitum; FSFL = FSF ad libitum. Concentrate was supplied at the amount of 0.8 or 1.2 kg/day per head for FL and TL, respectively. Cheese health properties greatly improved with FSFL diet, based on the exclusive use of fresh forage, that induced the increase in the content of molecules with antioxidant activity, as vitamin A, vitamin E and polyphenols, enhancing the oxidative stability, and the level of PUFA as rumenic acid (C18:2 c9t11) and α-linolenic acid (ALA, C18:3n-3). Cheeses from the DSF2 group showed levels of vitamin A, vitamin E and PUFA higher than SHL cheeses and comparable to those of FSF4 cheeses, whereas their ALA content was not different from that of FSFL cheeses. Evaluating those molecules affected by the level of fresh forage in the diet for their ability to trace the animals’ feeding regime, ALA and its ratio with linoleic acid (LA, C18:2n-6) (LA/ALA) exhibited an effective role as biomarker in discriminating cheese from animals fed fresh forage-based diets. The results showed how dehydrated sulla pellets, as an alternative to hay in periods of limited availability of fresh forage, can preserve the nutritional and health properties of dairy products with regards to their antioxidant capacity and FA profile.

Soft cheese with flax seeds

Currently, enrichment of dairy products with products of plant origin is becoming increasingly relevant. This technique allows us to improve the composition and ensure the functionality of the products. In this regard, we explored the use of flax in soft cheeses. For this, flax was used in the form of flour and seeds. The expediency of cheese enrichment with flax seeds has been established, since during grinding, the proportion of polyunsaturated fatty acids that imparts product functionality is reduced. At the next stage, the rationale for the use of flaxseeds was carried out, the method of processing them in the application phase, the organoleptic and physico-chemical parameters of the finished product were determined, the technology of soft cheese with flax seeds was developed. The innovative component of the new product was the use of bifidobacteria in the yeast, which give probiotic properties to soft cheese. Technological features of the production allowed to reduce the consumption of raw materials, increase product yield and reduce production time. In addition, the calculation of economic indicators shows the profitability of the production of this product. In the future, it is planned to expand the range of soft functional cheeses without ripening using fenugreek.

Improving the Technological and Nutritive Properties of Gluten-Free Bread by Fresh Curd Cheese Enrichment

Replacing wheat flour in the breadmaking process is a technology challenge since the elimination of gluten has a strong influence on bread quality. Proteins addition are often used to form a protein network capable of mimicking gluten-like structure, giving to dough a foaming support. This study aimed to evaluate the potential of denatured whey proteins coming from fresh curd cheese addition, to strengthening gluten-free dough structure, enhancing the breadmaking performance. Curd cheese additions were tested (5% up to 20%, weight/weight) and the effect on dough rheology behavior and bread quality was evaluated. Findings obtained revealed that the technology and nutritional properties of the bread can be enhanced by curd cheese addition, and such effects should be related to the composition and functionality of denatured whey proteins. Considering higher levels of curd cheese (20%) tested, improvements on bread quality was observed, leading to a considerable increase in bread volume (73%), softness (65%), with a significant reduction on staling kinetics (70%), comparing with control bread. Additionally, an improvement in nutritional value in terms of proteins (80%) and minerals content (P—50.0%, Mg—6.0%, and Ca—360.3%) was obtained, which can give an additional contribution to the nutritional daily requirements of celiac patients. Linear correlations between dough rheology properties and bread quality attributes were found, supporting the good breadmaking performance obtained.

Enrichment of sheep cheese with chia (Salvia hispanica L.) oil as a source of omega-3

This study evaluated the viability of using oil extracted from Salvia hispanica L. seeds as a source of omega-3 for sheep's cheese enrichment. Two concentrations (3 and 5 g/L) of chia oil prepared as emulsions stabilized with calcium caseinate were assayed in pressed sheep's milk cheese, and their physicochemical, microbiological and organoleptic parameters were evaluated throughout the 32-day ripening period. Sheep's milk coagulation parameters during cheese making were not affected by addition of the oil emulsion. The fortification with the emulsion had a positive impact on cheese yield, fat, dry matter and α-linolenic acid content. Moreover, total bacteria and lactic acid bacteria growth were not inhibited in the cheeses containing the highest oil concentration, confirming the hypothesis that oil addition would not interfere with the normal ripening process. Regarding the sensory analysis, the chia oil enriched cheeses showed a good acceptance by the judges.

Antimicrobial behavior of phage endolysin PlyP100 and its synergy with nisin to control Listeria monocytogenes in Queso Fresco

Hispanic-style fresh cheeses, such as Queso Fresco (QF), have been linked to numerous listeriosis outbreaks in the United States. In this work, we have studied the antilisterial behavior and effectiveness of the Listeria phage endolysin PlyP100 in QF, as well as the potential synergy between PlyP100 and nisin. PlyP100 showed similar bacterial reduction regardless of varying L. monocytogenes inoculum size in QF, and when the inoculation size was 1 Log CFU/g, no pathogen recovery after cheese enrichment was observed. PlyP100 was stable in QF for up to 28 days of cold storage exhibiting similar antilisterial activity regardless of when contamination with L. monocytogenes occurred. PlyP100 alone exhibited a strong listeriostatic effect in QF, on the contrary, nisin alone was not effective to control the pathogen in QF during cold storage. The combination of nisin and PlyP100 showed a strong synergy in QF with non-enumerable levels of L. monocytogenes after 4 weeks of refrigerated storage. Moreover, L. monocytogenes isolates from cheeses treated with nisin, PlyP100, and their combination did not develop resistance to nisin or PlyP100. Our results support the use of PlyP100 combined with nisin as an efficient L. monocytogenes control measure in QF.

A sensory- and consumer-based approach to optimize cheese enrichment with grape skin powders

The present study aimed to present a sensory- and consumer-based approach to optimize cheese enrichment with grape skin powders (GSP). The combined sensory evaluation approach, involving a descriptive and an affective test, respectively, was applied to evaluate the effect of the addition of grape skin powders from 2 grape varieties (Barbera and Chardonnay) at different levels [0.8, 1.6, and 2.4%; weight (wt) powder/wt curd] on the sensory properties and consumer acceptability of innovative soft cow milk cheeses. The experimental plan envisaged 7 products, 6 fortified prototypes (at rates of Barbera and Chardonnay of 0.8, 1.6, and 2.4%) and a control sample, with 1 wk of ripening. By means of a free choice profile, 21 cheese experts described the sensory properties of prototypes. A central location test with 90 consumers was subsequently conducted to assess the acceptability of samples. The GSP enrichment strongly affected the sensory properties of innovative products, mainly in terms of appearance and texture. Fortified samples were typically described with a marbling aspect (violet or brown as function of the grape variety) and with an increased granularity, sourness, saltiness, and astringency. The fortification also contributed certain vegetable sensations perceived at low intensity (grassy, cereal, nuts), and some potential negative sensations (earthy, animal, winy, varnish). The white color, the homogeneous dough, the compact and elastic texture, and the presence of lactic flavors resulted the positive drivers of preference. On the contrary, the marbling aspect, granularity, sandiness, sourness, saltiness, and astringency negatively affected the cheese acceptability for amounts of powder, exceeding 0.8 and 1.6% for the Barbera and Chardonnay prototypes, respectively. Therefore, the amount of powder resulted a critical parameter for liking of fortified cheeses and a discriminant between the 2 varieties. Reducing the GSP particle size and improving the GSP dispersion in the curd would reduce the effect of powder addition on sensory properties, thereby encouraging the use of these polyphenol-based fortifiers in cheeses. The proposed approach allowed the identification of sensory properties critical for product acceptability by consumers, thus helping the optimization of both fortifier characteristics and new cheese production and composition.

Enrichment of cheese with vitamin D3 and vegetable omega-3

Encapsulation technology provides many benefits to the food fortification: protection from oxygen and light, a best dispersion and biodisponibility, etc. In this study, vitamin D3 was encapsulated in two flaxseed oil emulsion formulations. Emulsions were stabilised with calcium caseinate in presence or absence of lecithin and used to standardise cheese milk. The use of flaxseed oil rich in alpha-linolenic acid allows fortifying the cheese in omega-3 and other polyunsaturated fatty acids (PUFA). Cheese yield and retention rate of proteins, fats and bioactive component were determined. Quantification of vitamin D3 and chemical stability of cheeses were performed up to 90 days of storage at 4 °C. Recovery level of vitamin D3 in cheese was, respectively, 91 and 84% in the presence or absence of lecithin. The encapsulation of vitamin D3 in the cheese in the form of emulsified particles of oil containing lecithin increased retention and stability of the vitamin in the curd. The fortification of cheese with vitamin D3 and PUFA had a positive impact on the composition, yield and chemical stability of the resultant cheese.

Duplex real-time PCR detection of type III effector tccP and tccP2 genes in pathogenic Escherichia coli and prevalence in raw milk cheeses

To develop a duplex real-time PCR assay targeting enterohaemorrhagic Escherichia coli (EHEC) type III effector TccP/TccP2-encoding genes which are pivotal to EHEC-mediated actin cytoskeleton reorganization in human intestinal epithelial cells. The specificity of the assay was demonstrated with DNA from EHEC reference strains and non-E. coli bacterial species. The detection limit was determined as five tccP or tccP2 copies per reaction. The assay was then evaluated on a large collection of 526 E. coli strains of human, animal, food and environmental origins. The results showed that tccP was restricted to a limited number of serotypes (i.e. O5:H(-) , O55:H7, O125:H6 and O157:H7). The tccP2 gene was present in a higher number of serotypes including the five most frequent EHEC serotypes (i.e. O26:H11, O103:H2, O111:H8, O145:H28 and O157:H7), and a few other serotypes that caused human infections (i.e. O4:H(-) , O45:H2 and O55:H7). A minority of O26:H11 and O103:H2 strains however tested negative for tccP2, though it is not known whether the lack of tccP2 affected their pathogenic potential. Real-time PCR analysis of 400 raw milk cheeses revealed the presence of tccP and/or tccP2 genes in 19·75% of the cheese enrichment suspensions. A highly specific and sensitive duplex real-time PCR method was developed for rapid and simultaneous detection of tccP and tccP2. Unpasteurized dairy products may be contaminated with E. coli strains carrying tccP and/or tccP2. The developed real-time PCR assay represents a valuable alternative to conventional PCR tests and should be useful for characterization of the virulome of pathogenic E. coli strains.