Fat Recovery Research Articles

Effect of protein-to-fat ratio of sheep milk on the composition, rheological properties and yield of PDO Pecorino Romano cheese

The aim of this work was to evaluate the effect of sheep milk protein-to-fat ratio (PFR) standardization, on the technological, physico-chemical and rheological properties of PDO Pecorino Romano cheese in the summer period (June and July). Two levels of PFR were investigated: i) ∼0.90 standardised PFR (SPFR) and ii) ∼0.76 natural PFR (NPFR). SPFR cheese had a lower fat content (34.2 ± 0.4 vs 36.8 ± 0.4) and a higher protein content (27.1 ± 0.3 vs 25.6 ± 0.8) than NPFR cheese. Consequently it was more compact, cohesive and hard compared to the latter. These aspects may contribute to reduce the time of ripening required to achieve a cheese suitable for grating use. In PDO Pecorino Romano cheese, this feature is monitored by the moisture in nonfat substance (MNFS), which at 8 months of ripening must be ≤47.0%. The standardization of milk contributed to achieve the suitable value earlier (46.0 ± 0.3 vs 47.2 ± 0.5). The standardization of the protein/fat ratio in sheep milk did not induce any significant effect on the lipolysis or proteolysis progress in the cheese during ripening.Increasing the PFR significantly increased the levels of protein but, significantly, reduced the levels of moisture in nonfat substance, fat-in-dry matter and salt-in-moisture. The percentage of milk fat recovered in the SPFR cheese was significantly higher than in the NPFR cheese. Increasing the PFR led to a significant decrease in the actual cheese yield, but a significant increase occurred in the normalized cheese yield. The final results prove that a standardization of PFR in cheese milk has a marked effect on cheese composition, fat recovery, and cheese yield.

Composition of ghee prepared from camel, cow and buffalo milk

Samples of milk from camel, cow and buffalo were analysed for fat contents Cream was separated from the respective milk and ghee was prepared by employing direct cream method. Yield of ghee was measured and recovery of fat obtained was estimated. The samples of ghee were analysed for selected compositional attributes. Yield of ghee and recovery of fat from camel milk was substantially lower compared to that from cow milk as well as buffalo milk. The content of unsaponifiable matter, cholesterol and FFA of ghee from camel milk was significantly lower (p>0.05) compared to ghee prepared from cow as well as buffalo milk. On the other hand, moisture content of ghee from camel milk was intermediate to that of the ghee from buffalo and cow milk.

Impact of Using Transglutaminase Enzyme in Manufacturing Low and High Fat Mozzarella Cheese

A method for the use of transglutaminase enzyme (TG) in rennet coagulated cheese making was adopted. Rennet was added to milk at 5°C and kept for 30 min, the TG was added and the mixture was left for 2 h before raising the temperature to 40°C for coagulation. The method was used for processing low and high fat mozzarella cheese with 2 levels of TG (0.02 and 0.05%). The cheese was stored for 28 days at 5°C and the cheese chemical composition, functional properties and sensory attributes were determined. The addition of TG significantly increased cheese yield, moisture, fat and protein recovery and improved stretchability and meltability. In low fat cheese, the yield, stretchability and meltability increased by 8%, 40% and 50% in 0.02% TG cheese and 15.1% 60% and 66% in 0.05% TG cheese, respectively. In high fat cheese, the yield, stretchability and meltability increased by 7.5%, 25% and 23.6% in 0.02% TG cheese and by 13.3%, 37.5% and 32.7% in 0.05% TG cheese, respectively. Organoleptically, treated cheese was more acceptable than the control. According to the results, the use of 0.02% of the enzyme for full fat cheese and 0.05% for low fat cheese are recommended.

Optimised Production of Biodiesel Synthesised from Waste Animal Fat

The fleshings produced during the pre-tanning process in tanneries and animal wastes generated from slaughter house are causing serious environmental concern because of improper disposal techniques. These solid wastes contain fat and proteins which can be recovered for wide variety of applications. The fats extracted from these wastes are used as feedstock for the production of biodiesel, which serves as an alternate for conventional diesel fuel because of their sustainability. The use of these animal fats ruled out the issues over the ‘Food versus Fuel’ conflict, as edible feed stocks were used in the production of biodiesel earlier. This work projects on the synthesis of biodiesel from waste animal fats by the means of methyl-based transesterification. A maximum fat recovery of 85% was achieved by the means of autoclave heat treatment method. The refining of fat was carried out by following acid degumming, where Orthophosphoric acid was mixed with the fat to remove the phospholipids as residues. Pretreatment of the extracted fat was done using glycerolysis, where the FFA % of these fats were reduced from 7% to 0.25% with a recorded efficiency of 96.4%. Alkali catalysed transesterification was carried out by investigating various operating parameters like oil/alcohol molar ratio, catalyst concentration, temperature and reaction time and optimising them. The optimised process parameters produced a maximum yield of 94% biodiesel. The fuel properties of the produced biodiesel were compared with the ordinary diesel fuel based on both ASTM D-6751 and IS 15607: 2005 standards.

Buffalo milk composition, processing factors, whey constituents recovery and yield in manufacturing Mozzarella cheese

Abstract Mozzarella cheese is typically from Italy and consumed in the whole world. The aim of this study was to characterize the manufacture of Mozzarella produced similarly to Italian in a Brazilian dairy industry regarding the milk composition usage, factors involved in the production process, use of raw materials and cheese yield. Was monitored the Mozzarella yield (MY), milk composition, manufacturing of Mozzarella cheese and recovery of whey constituents of 30 lots of Mozzarella cheese in a dairy brazilian industry. Overall, processing reached an adequate MY for this type of cheese, being below 5.0 L kg-1. We find values of 5.93 ± 1.87; 34.97 ± 2.70; 33.39 ± 2.85; 95.04 ± 4.18; 44.02 ± 2.00; and 66.82 ± 3.36 respectively for recovery of fat, protein, casein, lactose, total solids and solids-not-fat in whey. The milk used by the dairy industry had satisfactory physicochemical characteristics. The manufacturing of Mozzarella cheese was efficient.

Effect of uncertainty in composition and weight measures in control of cheese yield and fat loss in large cheese factories.

Our objective was to develop a computer-based cheese yield, fat recovery, and composition control performance measurement system to provide quantitative performance records for a Cheddar and mozzarella cheese factory. The system can be used to track trends in performance of starter cultures and vats, as well as systematically calculate theoretical yield. Yield equations were built into the spreadsheet to evaluate cheese yield performance and fat losses in a cheese factory. Based on observations in commercial cheese factories, sensitivity analysis was done to demonstrate the sensitivity of cheese factory performance to analytical uncertainty of data used in the evaluation. Analytical uncertainty in the accuracy of milk weight and milk and cheese composition were identified as important factors that influence the ability to manage consistency of cheese quality and profitability. It was demonstrated that an uncertainty of ±0.1% milk fat or milk protein in the vat causes a range of theoretical Cheddar cheese yield from 10.05 to 10.37% and an uncertainty of yield efficiency of ±1.5%. This equates to ±1,451 kg (3,199 lb) of cheese per day in a factory processing 907,185 kg (2 million pounds) of milk per day. The same is true for uncertainty in cheese composition, where the effect of being 0.5% low on moisture or fat is about 484 kg (1,067 lb) of missed revenue opportunity from cheese for the day. Missing the moisture target causes other targets such as fat on a dry basis and salt in moisture to be missed. Similar impacts were demonstrated for mozzarella cheese. In analytical performance evaluations of commercial cheese quality assurance laboratories, we found that analytical uncertainty was typically a bias that was as large as 0.5% on fat and moisture. The effect of having a high bias of 0.5% moisture or fat will produce a missed opportunity of 484 kg of cheese per day for each component. More accurate rapid methods for determination of moisture, fat, and salt contents of cheese in large cheese factories will improve the accuracy of yield performance evaluation and control of consistency of cheese composition and quality.

Influence of Homogenization Conditions of Buffalo Milk on the Recovery of Milk Constituents and Yield of Mozzarella Cheese

Mozzarella cheese making involves losses of milk constituents, especially during plasticizing stage of cheese curd. Buffalo milk is considered more suitable than cow milk for Mozzarella cheese making, especially in terms of colour, yield and stretch property of resultant product. Homogenization of milk reduces the losses of milk constituents, increases its whiteness and is expected to render superior flavor to cheese. The fat globule size for buffalo milk is larger and the cheese tends to be firmer and chewy as compared to cow milk counterpart. Homogenization of buffalo milk is of significance in this regard since it can improve the color, recovery of milk constituents culminating in higher cheese yield, a mellower product with lower tendency to oil-off during baking applications. Since the conditions of homogenization affects the recovery of milk constituents, it was decided to study temperature and pressure of homogenization on such aspect including cheese yield. Homogenization of standardized buffalo milk at 55 or 65oC and 4.90 MPa (P2) pressure is found beneficial with regard to recovery of milk fat, while use of lower pressure i.e. 2.45 MPa (P1) at above temperatures is found beneficial for protein and TS recoveries. P2 pressure is more beneficial than P1 pressure in improving the fat recovery in buffalo milk Mozzarella cheese. There is an improvement in the yield of Mozzarella cheese with an increase in homogenization pressure. The yield of Mozzarella cheese prepared using buffalo milk homogenized at P2 and P1 pressure (at 65oC) was 17.00% and 16.10% respectively. The recoveries of milk fat, protein and TS and per cent yield for control cheese was 83.68%, 84.10%, 56.74% and 14.53% respectively.

Transfer of oxytetracycline from ovine spiked milk to whey and cheese

Cheese-making trials with ovine milk spiked with oxytetracycline (OTC) at maximum residue limit (MRL) level were performed to study the OTC distribution between whey and cheese, and assess its effect in cheese-making process and cheese composition. An in-house validated method, based on liquid chromatography-tandem mass spectrometry, was adopted to detect OTC in milk, whey and cheeses. The MRL OTC spike induced a delay in the pH lowering causing a higher moisture content in 1-day OTC cheese compared with the control cheese. No effects of OTC were observed on the mass balance of the process, on the recovery of fat and protein and, in general, on physico-chemical parameters and gross composition of obtained cheeses. OTC was mainly recovered in the 1-day cheeses (61 ± 5%). Despite a 17 ± 8% OTC reduction observed during cheese ripening, probably due to partial degradation, remaining residues were not negligible and could contribute to reach the acceptable daily intake.

Effects of different genotypes at the CSN3 and LGB loci on milk and cheese-making characteristics of the bovine Cinisara breed

The Cinisara is an autochthonous Sicilian bovine breed reared mainly for production of Caciocavallo Palermitano, a typical stretched-curd cheese. The distribution of A and B alleles at both the β-lactoglobulin (LGB) and κ-casein (CSN3) loci in Cinisara cows and their influence on milk traits and cheese yield and composition were analysed. The LGB alleles are associated with significantly different effects on whey protein level (lower for BB genotype, P < 0.01), and casein index (higher value for BB genotype, P < 0.001), while CSN3 alleles were associated with significantly different effects on milk yield and coagulation properties; the BB genotype showed higher values for milk yield (P < 0.01) and curd firmness (a30 P < 0.01 and a2rP < 0.01) and lower values for coagulation and curd firming time (P < 0.01) than the AA genotype. Cheese made with LGB BB milk showed higher percentage protein recovery (P < 0.01); cheese made with CSN3 BB milk showed higher percentage fat recovery (P < 0.05).

Influence of rendering methods on yield and quality of chicken fat recovered from broiler skin.

ObjectiveIn order to utilize fat from broiler byproducts efficiently, it is necessary to develop an appropriate rendering procedure and establish quality information for the rendered fat. A study was therefore undertaken to evaluate the influence of rendering methods on the amounts and general properties of the fat recovered from broiler skin.MethodsThe yield and quality of the broiler skin fat rendered through high and lower energy microwave rendering (3.6 W/g for 10 min and 2.4 W/g for 10 min for high power microwave rendering (HPMR) and high power microwave rendering (LPMR), respectively), oven baking (OB, at 180°C for 40 min), and water cooking (WC, boiling for 40 min) were compared.ResultsMicrowave-rendered skin exhibited the highest yields and fat recovery rates, followed by OB, and WC fats (p<0.05). HPMR fat had the highest L*, a*, and b* values, whereas WC fat had the highest moisture content, acid values, and thiobarbituric acid (TBA) values (p<0.05). There was no significant difference in the acid value, peroxide value, and TBA values between HPMR and LPMR fats.ConclusionMicrowave rendering at a power level of 3.6 W/g for 10 min is suggested base on the yield and quality of chicken fat.

Effects of Different Manufacturing Methods on Yield, Physicochemical and Sensory Properties of Mozzarella Cheese

The effect of different mozzarella cheese manufacturing methods, i.e. direct acidification (DA), starter culture (SC) and their combination method (CM) on physicochemical, yield, texture, color and sensory properties of the product were compared. Chemical analyses of samples revealed that the SC cheese had higher fat, moisture, ash, titratable acidity, actual and adjusted yields and fat recovery than DA cheese. DA cheese showed higher springiness, cohesiveness, and hardness than CM and SC cheeses, due to denser and elastic protein network, whereas meltability and adhesiveness of DA cheese was lower than CM and SC samples. SC cheese had significantly higher b-value than DA sample. The sensory evaluation revealed that the SC cheese had higher sensory quality than other cheeses in fresh state and during 45 days of storage. In general, sensory scores of all mozzarella cheeses were acceptable up to 15th day of storage and thereafter decreased progressively till the end of storage period.

Effect of Carrageenan on Physicochemical and Functional Properties of Low‐Fat Colby Cheese

The effect of carrageenan (κ-carrageenan, ι-carrageenan, and λ-carrageenan) on the physiochemical and functional properties of low-fat Colby cheese during ripening was investigated. Protein, fat, and moisture contents; the soluble fractions of the total nitrogen at pH 4.6; protein and fat recovery; and the actual yield and dry matter yield (DM yield) were monitored. Hardness, springiness, and the storage modulus were also evaluated to assess the functional properties of the cheese. Moreover, the behavior of water in the samples was investigated to ascertain the underlying mechanisms. The results indicated that 0.15 g/kg κ-carrageenan had no significant effect on the actual yield and DM yield, and physiochemical and functional properties of low-fat Colby cheese. The protein content increased in the low-fat cheese and low-fat cheese containing κ-carrageenan, and the moisture in the nonfat substance (MNFS) decreased in both samples, which contributed to the harder texture. The addition of 0.3 g/kg ι-carrageenan and 0.3 g/kg λ-carrageenan improved the textural and rheological properties of low-fat cheese by 2 ways: one is increasing the content of bound and expressible moisture due to their high water absorption capacity and the other is interfering with casein crosslinking, thereby further increasing MNFS and the actual yield.

The nonlinear effect of somatic cell count on milk composition, coagulation properties, curd firmness modeling, cheese yield, and curd nutrient recovery

The aim of this study was to investigate the relationships between somatic cell count (SCC) in milk and several milk technological traits at the individual cow level. In particular, we determined the effects of very low to very high SCC on traits related to (1) milk yield and composition; (2) coagulation properties, including the traditional milk coagulation properties (MCP) and the new curd firming model parameters; and (3) cheese yield and recovery of milk nutrients in the curd (or loss in the whey). Milk samples from 1,271 Brown Swiss cows from 85 herds were used. Nine coagulation traits were measured: 3 traditional MCP [rennet coagulation time (RCT, min), curd firming rate (k20, min), and curd firmness after 30 min (a30, mm)] and 6 new curd firming and syneresis traits [potential asymptotic curd firmness at infinite time (CFP, mm), curd firming instant rate constant (kCF, % × min−1), syneresis instant rate constant (kSR, % × min−1), rennet coagulation time estimated using the equation (RCTeq, min), maximum curd firmness achieved within 45 min (CFmax, mm), and time at achievement of CFmax (tmax, min)]. The observed cheese-making traits included 3 cheese yield traits (%CYCURD, %CYSOLIDS, and %CYWATER, which represented the weights of curd, total solids, and water, respectively, as a percentage of the weight of the processed milk) and 4 nutrient recoveries in the curd (RECFAT, RECPROTEIN, RECSOLIDS, and RECENERGY, which each represented the percentage ratio between the nutrient in the curd and milk). Data were analyzed using a linear mixed model with the fixed effects of days in milk, parity, and somatic cell score (SCS), and the random effect of herd-date. Somatic cell score had strong influences on casein number and lactose, and also affected pH; these were traits characterized by a quadratic pattern of the data. The results also showed a negative linear relationship between SCS and milk yield. Somatic cell score influenced almost all of the tested coagulation traits (both traditional and modeled), with the exceptions of k20, CFP, and kSR. Gelation was delayed when the SCS decreased (slightly) and when it increased (strongly) with respect to a value of 2, as confirmed by the quadratic patterns observed for both RCT and RCTeq. The SCS effect on a30 showed a quadratic pattern almost opposite to that observed for RCT. With respect to the CFt parameters, kCF decreased linearly as SCS increased, resulting in a linear decrease of CFmax and a quadratic pattern for tmax. Milk SCS attained significance for %CYCURD, %CYWATER, and RECPROTEIN. As the SCS increased beyond 3, we observed a progressive quadratic decrease of the water retained in the curd (%CYWATER), which caused a parallel decrease in %CYCURD. With respect to RECPROTEIN, the negative effect of SCS was almost linear. Recovery of fat and (consequently) RECENERGY was characterized by a more evident quadratic trend, with the most favorable values associated with an intermediate SCS. Together, our results confirmed that high SCS has a negative effect on milk composition and technological traits, highlighting the nonlinear trends of some traits across the different classes of SCS. Moreover, we report that a very low SCS has a negative effect on some technological traits of milk.

Coalho Cheese Made with Protease from Thermomucor indicae-seudaticae N31: Technological Potential of the New Coagulant for the Production of High-Cooked Cheese.

The aim of this study was to explore the use of a new coagulant from Thermomucor indicae-seudaticae N31 for the manufacture of a high-cooked starter-free cheese variety, by evaluating its physicochemical and functional characteristics in comparison to cheeses made with a traditional commercial coagulant. Coalho cheese was successfully produced with the new protease as it exhibited comparable characteristics to the one produced using the commercial enzyme: pH behavior during manufacture; cheese composition; protein and fat recovery; and cheese yield. In addition, during storage, melting was low and not affected by storage time; the increase of TCA 12% soluble nitrogen (% of total nitrogen) was lower than half of that of pH 4.6 soluble nitrogen (% of total nitrogen); concentration of β-CN significantly decreased, whereas αs1 -CN concentration was not affected by storage time.

Genetic and environmental relationships of different measures of individual cheese yield and curd nutrients recovery with coagulation properties of bovine milk

The aim of this study was to elucidate the relationships between various cheesemaking-related traits, namely the well-known traditional milk coagulation properties (MCP), the new curd firming and syneresis traits, the cheese yield, and the curd nutrient recoveries or whey losses (all measured at the individual level). Data were obtained from 1,167 Brown Swiss cows reared in 85 herds. A 2-L milk sample was collected once from each animal and assessed for 10 phenotypes related to changes in curd firmness (CF) over time, plus 7 cheesemaking traits. The CF-related traits included 4 traditional single-point lactodynamographic properties [rennet coagulation time (RCT, min); time to a CF of 20mm, min; and the CF 30 and 45min after rennet addition (a30 and a45, respectively)], 4 parameters used to model the 360 CF data recorded over time for each milk sample [the potential asymptotic CF at infinite time (CFP, mm); the CF instant rate constant, % × min−1; the syneresis instant rate constant, % × min−1; and the RCT obtained from modeling individual samples], and 2 traits calculated from individual equations [the maximum CF(CFmax, mm); and the time at CFmax, min]. The cheesemaking traits included 3 cheese yield traits (weights of the fresh curd, curd solids and curd moisture as percent of the weights of the processed milk) and 4milk nutrient recoveries in the curd (calculated as the percent ratios between a given nutrient in the curd versus that in the processed milk). Bayesian methodology-based multivariate analyses were used to estimate the phenotypic, additive genetic, herd/date, and residual relationships between the aforementioned traits, whereas statistical inferences were based on the marginal posterior distributions of the parameters of concern. The a45, CFP, and CFmax traits were genetically associated with all of the percent cheese yield traits (the additive genetic correlations varied from 0.752 to 0.855 for a45; 0.496 to 0.583 for CFP; and 0.750 to 0.801 for CFmax) and the nutrient recovery traits (additive genetic correlations varied from 0.296 to 0.901 for a45; 0.428 to 0.697 for CFP; and 0.412 to 0.941 for CFmax). Moreover, the nutrient recoveries for fat, solids, and energy exhibited large additive genetic correlations with the other coagulation and curd firming traits. In particular, recovery of protein and fat were found to be powerful instruments for understanding the relationships between milk technological properties and cheese quantity or quality. We observed only weak genetic relationships with the milk quality and MCP traits, suggesting that the highly heritable trait of protein recovery should perhaps be included as a genetic index when seeking to improve cheesemaking efficiency at the population level. In contrast, we found that fat recovery exhibited moderate genetic variation and could be improved through the CF over time traits, especially using those recorded during the late phase of the curd firming process. Moreover, our results demonstrated that the traditional MCP have limited relevance for predicting individual cheese yield. Therefore, their use for this purpose in the dairy industry and breeding programs seems questionable.

Fat recovery from dissolved air flotation sludge

Fat recovery from dissolved air flotation sludge

Caloric restriction induces energy-sparing alterations in skeletal muscle contraction, fiber composition and local thyroid hormone metabolism that persist during catch-up fat upon refeeding.

Weight regain after caloric restriction results in accelerated fat storage in adipose tissue. This catch-up fat phenomenon is postulated to result partly from suppressed skeletal muscle thermogenesis, but the underlying mechanisms are elusive. We investigated whether the reduced rate of skeletal muscle contraction-relaxation cycle that occurs after caloric restriction persists during weight recovery and could contribute to catch-up fat. Using a rat model of semistarvation-refeeding, in which fat recovery is driven by suppressed thermogenesis, we show that contraction and relaxation of leg muscles are slower after both semistarvation and refeeding. These effects are associated with (i) higher expression of muscle deiodinase type 3 (DIO3), which inactivates tri-iodothyronine (T3), and lower expression of T3-activating enzyme, deiodinase type 2 (DIO2), (ii) slower net formation of T3 from its T4 precursor in muscles, and (iii) accumulation of slow fibers at the expense of fast fibers. These semistarvation-induced changes persisted during recovery and correlated with impaired expression of transcription factors involved in slow-twitch muscle development. We conclude that diminished muscle thermogenesis following caloric restriction results from reduced muscle T3 levels, alteration in muscle-specific transcription factors, and fast-to-slow fiber shift causing slower contractility. These energy-sparing effects persist during weight recovery and contribute to catch-up fat.

Membrane fractionation of herring marinade for separation and recovery of fats, proteins, amino acids, salt, acetic acid and water

In the production of marinated herring, nearly one ton of acidic saline marinade is produced per 1.5tons herring fillet. This spent marinade contains highly valuable compounds such as proteins and amino acids. Membranes are suited to recover these substances. In this work, six membrane stages are employed: microfiltration (MF) (0.2μm), ultrafiltration (UF) (50, 20, 10 and 1kDa) and nanofiltration (NF).The most promising stages are 50kDa UF and NF based on SDS–PAGE analyses and total amino acid concentration. The 50kDa stage produces a protein concentrate (>17kDa). NF produces a retentate containing sugars, amino acids and smaller peptides and a NF permeate containing salt and acetic acid ready for reuse. 42% of the spent marinade is recovered to substitute fresh water and chemicals. The waste water amount is reduced 62.5%. Proteins are concentrated 30 times, while amino acids and smaller peptides are concentrated 11 times.

Influence of milk somatic cell content on Parmigiano-Reggiano cheese yield.

The aim of this study was to determine the influence of the somatic cell content (SCC) of milk on Parmigiano-Reggiano cheese yield, produced in commercial cheese factories under field conditions. The study was carried out following the production of 56 batches of Parmigiano-Reggiano in 13 commercial cheese factories by processing milk collected from Italian Friesian cattle herds. The vat-milk (V-milk) used for making each cheese batch was obtained by mixing evening milk (partially skimmed following spontaneous separation of fat overnight, natural creaming) and morning milk. The batches of cheese produced were divided into 5 classes according to the SCC value of the evening milk determined prior to natural creaming (class 1, from 0 to 200,000; 2, 201,000-300,000; 3, 301,000-400,000; 4, 401,000-500,000; 5, over 501,000 cells/ml). The cheese yield was calculated as the amount of 24-h cheese, expressed in kilograms, obtained from 100 kg of V-milk (24 h ACY). The values of fat, crude protein, true protein, casein and 24 h ACY of V-milk were negatively correlated with the somatic cell score (SCS) of the evening milk. Conversely, a positive correlation was observed between chloride and SCS. Fat, protein fractions (crude protein, casein and whey proteins), P and titratable acidity of V-milk were positively correlated with its 24 h ACY, while chloride, pH and SCS showed a negative correlation. A significant drop in 24 h ACY was observed in classes 3, 4 and 5, therefore when the SCC of the evening milk exceeded 300,000 cells/ml. Finally a lower recovery of milk fat in cheese was observed as SCC of evening milk increase.

How dieting makes the lean fatter: from a perspective of body composition autoregulation through adipostats and proteinstats awaiting discovery.

Whether dieting makes people fatter has been a subject of considerable controversy over the past 30 years. More recent analysis of several prospective studies suggest, however, that it is dieting to lose weight in people who are in the healthy normal range of body weight, rather than in those who are overweight or obese, that most strongly and consistently predict future weight gain. This paper analyses the ongoing arguments in the debate about whether repeated dieting to lose weight in normal-weight people represents unsuccessful attempts to counter genetic and familial predispositions to obesity, a psychosocial reaction to the fear of fatness or that dieting per se confers risks for fatness and hence a contributing factor to the obesity epidemic. In addressing the biological plausibility that dieting predisposes the lean (rather than the overweight or obese) to regaining more body fat than what had been lost (i.e. fat overshooting), it integrates the results derived from the re-analysis of body composition data on fat mass and fat-free mass (FFM) losses and recoveries from human studies of experimental energy restriction and refeeding. These suggest that feedback signals from the depletion of both fat mass (i.e. adipostats) and FFM (i.e. proteinstats) contribute to weight regain through the modulation of energy intake and adaptive thermogenesis, and that a faster rate of fat recovery relative to FFM recovery (i.e. preferential catch-up fat) is a central outcome of body composition autoregulation in lean individuals. Such a temporal desynchronization in the restoration of the body's fat vs. FFM results in a state of hyperphagia that persists beyond complete recovery of fat mass and interestingly until FFM is fully recovered. However, as this completion of FFM recovery is also accompanied by fat deposition, excess fat accumulates. In other words, fat overshooting is a prerequisite to allow complete recovery of FFM. This confers biological plausibility for post-dieting fat overshooting - which through repeated dieting and weight cycling would increase the risks for trajectories from leanness to fatness. Given the increasing prevalence of dieting in normal-weight female and male among young adults, adolescents and even children who perceive themselves as too fat (due to media, family and societal pressures), together with the high prevalence of dieting for optimizing performance among athletes in weight-sensitive sports, the notion that dieting and weight cycling may be predisposing a substantial proportion of the population to weight gain and obesity deserves greater scientific scrutiny.