Effect of autoclaving on dietary fibre content of beetroot (Beta vulgaris). Evaluation by different methods

Modifications of dietary fibre in beetroot during autoclaving have been evaluated by different methods: acid detergent (raw=1.45%; processed=1.17%) and neutral detergent (raw=2.30%; processed=2.00%), the enzymatic-gravimetric method of Asp (raw=3.35%; processed=3.34%), HPLC (raw=1.42%; processed=1.60%) and 3,5-dimethylphenol (raw=0.36; processed=0.28%). The correlation between different methodologies was studied. Autoclaving was carried out at 121°C under pressure for 15 min. Variance analysis indicated that quantitative variations originating in the thermic treatment were not statistically significant (P>0.05).     

Autoclaving effects on the dietary fibre content of carrots (Daucus carota) and turnips (Brassica napus): an evaluation of different methods

Different methods have been used to evaluate variations in the dietary fibre content of carrots and turnips during autoclaving. Autoclaving was carried out at 121°C under pressure for 15 min. The methods used were the gravimetric (neutral and acid detergent fibre) method, the enzymatic-gravimetric method for (insoluble and soluble fibre and the spectrophotometric method for pectic substances. When the methodologies were compared it was observed that in raw carrots and turnips, the neutral detergent fibre and insoluble fibre contents were statistically different (P<0.05). This was not the case for processed samples of the vegetables. The correlation between the different methodologies was studied. A good correlation was found between neutral detergent fibre and insoluble fibre in raw turnips (r = 0.999). Variance analysis indicated that quantitative variations resulting after thermal treatment were statistically significant (P<0.05) for neutral detergent fibre in carrots (raw = 1.97%, processed = 1.68%), and for pectic substances in carrots (raw = 0.54%, processed = 0.47%) and turnips (raw = 0.33%, processed = 0.25%). Optical microscopy has been used to identify different dietary fibre components in raw and processed samples.     

Effect of household processing on the in vitro bioavailability of iron in mungbean (Vigna radiata)

BACKGROUND: Mungbean (Vigna radiata) is a major source of energy and protein in developing countries, especially for the vegetarian population. Improvement of the bioavailability of iron in mungbean by common household processes could make a significant contribution to the nutrition of people in countries where iron-deficiency anemia is widespread. OBJECTIVE: The study was conducted to determine the effect of common household processes on nutritional and antinutritional factors as well as in vitro bioavailability of iron in mungbean. METHODS: Mungbean was subjected to various domestic processes such as dehulling, pressure cooking, germination, and fermentation. The effects of these processes on proximate composition, antinutritional factors (phytin phosphorus, polyphenols, and neutral detergent), and iron, including ionizable iron, were determined. RESULTS: No significant change in crude protein content was observed. There was a significant (p < or = .05) increase in fiber content after germination. Ash content decreased significantly (p < or = .05) after all processing methods. The processing methods resulted in a significant (p < or = .05) reduction in phytin phosphorus and polyphenols. Pressure cooking significantly (p < or = .05) decreased the neutral detergent fiber, whereas fermentation and germination increased it. The phytate:iron molar ratio of processed mungbean revealed that the maximum reduction was in germinated and fermented samples. Ascorbic acid content increased significantly (p < or = .05) after germination. The in vitro bioavailability of iron in raw mungbean was 7.32%. All of the processing methods resulted in an increase in iron bioavailability in vitro; the maximum bioavailability was in germinated cooked mungbean (12.52%), followed by fermented cooked mungbean and germinated raw mungbean (both 11.04%). CONCLUSIONS: Suitable processing techniques can improve the in vitro bioavailability of iron from mungbean. If mungbean products with enhanced iron bioavailabilty are developed, they could help improve the iron status of the population.     

Storage of fresh and ensiled forages by freezing affects fibre and crude protein fractions

The effect of freezing on fibre and crude protein fractions of forages was determined. Fresh and ensiled lucerne and fresh bromegrass were processed immediately after collection or stored at ?25°C for 1 day or 1, 6 or 12 months before drying at 55°C. Samples were frozen quickly by submersion in liquid nitrogen or slowly at ?25°C. Samples which were not frozen were processed immediately or after 1 h delay at room temperature. All treatments were replicated (n = 3). Samples were analysed for crude protein (CP), trichloroacetic acid soluble CP (TSCP), phosphate buffer soluble CP (BSCP), neutral detergent insoluble CP (NDCP), acid detergent insoluble CP (ADCP), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent sulphuric acid lignin (lignin) and ash. Freezing decreased BSCP and increased NDCP by more than 40% for bromegrass. Freezing also changed NDF, ADF, lignin, ash, CP and ADCP in different ways depending on forage type and length of time frozen. No significant effects were observed for method of freezing or a 1-h delay in processing. An additional experiment showed that freeze-drying resulted in less insoluble protein than ovendrying. Prior freezing of forages appeared inconsistently to change the extent of gaseous loss during drying, and resulted in precipitation of protein. These changes also affected fibre estimates. Fresh forages should not be frozen and thawed before analysis of protein or fibre fractions.     

Detection of central nervous system tissue as bovine spongiform encephalopathy specified risk material in traditional Turkish meat products

BACKGROUND: This study used enzyme‐linked immunosorbent assay kits to investigate the presence of central nervous system (CNS) tissue in commercial raw and processed traditional Turkish meat products offered for consumption in various markets. RESULTS: Ninety‐six raw traditional Turkish meat products (32 fresh raw beef patties, 32 cig kofta, 32 pastirma) and 64 processed traditional Turkish meat products (32 doner kebabs and 32 fresh processed beef patties) were analysed. CNS tissue was not found in pastirma, doner kebab, or fresh processed beef patty samples. The levels of CNS contamination in fresh raw beef patties were low (0.1% absorbance standard; 3.1%) and moderate (0.2% absorbance standard; 6.2%). The level of contamination in the cig kofta was low (0.1% absorbance standard; 18.8%). CONCLUSION: CNS tissue was present in all raw traditional Turkish meat products except for pastirma. Copyright © 2011 Society of Chemical Industry     

Effects of home preparation on organophosphorus pesticide residues in raw cucumber

The effects of washing with tap water and different detergent solutions, storage at different temperatures and ultrasonic cleaning on organophosphorus pesticide (trichlorfon, dimethoate, dichlorvos, fenitrothion, and chlorpyrifos) residue levels in raw cucumber was investigated. Analysis was carried out by liquid chromatography–tandem mass spectrometry. Washing with detergent solutions proved more effective than tap water. The organophosphorus pesticides reduced from 31.1% to 98.8% after washing with detergent solutions for 20 min. Among detergent solutions, 5% sodium carbonate solution caused the greatest loss in trichlorfon and dimethoate, and 5% sodium bicarbonate solution caused the greatest loss in dichlorvos, fenitrothion and chlorpyrifos. Storage at 4 °C for 48 h caused pesticides reduction by 60.9–90.2%. Ultrasonic cleaning for 20 min lowered pesticides by 49.8–84.4%. The data indicated that home preparation is effective for the reduction of organophosphorus pesticide residues in raw cucumber and it is useful for reducing the dietary exposure.     

Composition and some physical properties of different pea cultivars

The basic composition and physical properties such as firmness and cookability were determined for eight varieties or lines of pea and field pea. The discriminant components of peas were protein (19.5–28.9%), starch (46.1–54.6%) and in a less extent acid detergent fibre (10.0–11.6%) and dietary fibre (18.1–21.1%). The resistance of raw peas to crushing, expressed by the minimum destruction force, was highly differentiated (286–468 N). The relationships between the firmness of peas and their size, and the content of protein or acid detergent fibre, were found. High differences in cookability of peas did not correlate with either the firmness of raw peas or their use value.     

Occurrence and survival of verocytotoxin-producing Escherichia coli O157 in meats obtained from retail outlets in The Netherlands.

In 1996 and 1997, 2,941 fresh and processed meat products obtained from supermarkets and butcher shops in The Netherlands were examined for the presence of verocytotoxin-producing Escherichia coli of serogroup O157 (O157 VTEC). Additionally, the fate of O157 VTEC in raw meat products stored at low temperatures and the effect of different additives were evaluated. O157 VTEC strains were isolated from 6 (1.1%) of 571 samples of raw minced beef, 2 (0.5%) of 402 samples of raw minced mixed beef and pork, 1 (1.3%) of 76 samples of raw minced pork, 1 (0.3%) of 393 samples of other raw pork products, and 1 (0.3%) of 328 samples of cooked or fermented ready-to-eat meats. Other raw beef products (n = 223) and meat samples originating from poultry (n = 819), sheep or lamb (n = 46), or wild animals (n = 83) were all found to be negative for O157 VTEC. For the survival experiments we used tartaar (minced beef with a fat content of less than 10%) and filet americain (tartaar mixed with a mayonnaise-based sauce [80 to 20%]). The O157 VTEC strain tested was able to survive in tartaar and filet americain stored at -20, 0, 5, or 7 degrees C for 3 days. At both 7 and at 15 degrees C, O157 VTEC counts in tartaar and filet americain remained virtually unchanged throughout a storage period of 5 days. Addition of acetic acid (to pH 4.0), sodium lactate (1 and 2% [wt/wt]), or components of the lactoperoxidase-thiocyanate-hydrogen peroxide system to filet americain did not result in a reduction of viable O157 VTEC cells during storage at 7 or 15 degrees C. It was concluded that raw meat contaminated with O157 VTEC will remain a hazard even if the meat is held at low or freezing temperatures.     

Sensory,functional characteristics and in vitro digestibility of snacks supplemented with non-traditional ingredient raw and processed fenugreek

Fenugreek seeds were germinated, soaked and roasted and were evaluated for nutritional properties. Raw and processed fenugreek seeds were used to develop snack product. Snacks were examined for the sensorial, functional, antinutritional properties and in vitro digestibility. Using sensory analysis, 5% level of substitution of raw and processed fenugreek was accepted for the development of extruded snacks. Lateral expansion was highest for snacks prepared from processed fenugreek (163.0% to 206.1%) than raw fenugreek (162.5 to 168.7%), and vice versa for bulk density. The antioxidant activity and total phenolic content were highest for snacks prepared from germinated fenugreek (7.30% to 9.87% and 1.352 to 3.561 mg GAE g⁻¹ of sample) and lowest for snacks prepared from raw fenugreek (6.68% to 7.03% and 1.29 to 2.76 mg GAE g⁻¹ of sample). Not only extrusion but also processing such as soaking, roasting and germination reduced the antinutritional content of the snack product. Both in vitro digestibilities increased with extrusion cooking. In vitro digestibility was also found to be higher in snacks prepared from processed fenugreek than raw fenugreek. Therefore, development of such functional foods using processed fenugreek would raise the consumer demand and benefit the population by increasing the health status.     

Comparison of dry sheet media and conventional agar media methods for enumerating yeasts and molds in food

A study was done to compare Nissui Compact Dry Yeast and Mold plates (CDYM), 3M Petrifilm Yeast and Mold count plates (PYM), dichloran-rose bengal chloramphenicol (DRBC) agar, and dichloran 18% glycerol (DG18) agar for enumerating yeasts and molds naturally occurring in 97 foods (grains, legumes, raw fruits and vegetables, nuts, dairy products, meats, and miscellaneous processed foods and dry mixes). Correlation coefficients for plates incubated for 5 days were DG18 versus DRBC (0.93), PYM versus DRBC (0.81), CDYM versus DG18 (0.81), PYM versus DG18 (0.80), CDYM versus DRBC (0.79), and CDYM versus PYM (0.75). The number of yeasts and molds recovered from a group of foods (n = 32) analyzed on a weight basis (CFU per gram) was not significantly different (alpha = 0.05) when samples were plated on DRBC, DG18, PYM, or CDYM. However, the order of recovery from foods (n = 65) in a group analyzed on a unit or piece basis, or a composite of both groups (n = 97), was DRBC > DG18 = CDYM > PYM. Compared with PYM, CDYM recovered equivalent, significantly higher (alpha = 0.05) or significantly lower (alpha = 0.05) numbers of yeasts and molds in 51.5, 27.8, and 20.6%, respectively, of the 97 foods tested; respective values were 68.8, 15.6, and 15.6% in the small group (n = 32) and 43.1, 33.8, and 23.1% in the large group (n = 65) of foods. The two groups contained different types of foods, the latter consisting largely (73.8%) of raw fruits (n = 16) and vegetables (n = 32). Differences in efficacy of the four methods in recovering yeasts and molds from foods in the two groups are attributed in part to differences in genera and predominant mycoflora. While DG18 agar, CDYM, and PYM appear to be acceptable for enumerating yeasts and molds in the foods analyzed in this study, overall, DRBC agar recovered higher numbers from the 97 test foods, thereby supporting its recommended use as a general purpose medium for mycological analysis.     

Sodium sulphite effects on recovery and composition of detergent fibre and lignin from forage legumes varying in levels of proanthocyanidins

Alfalfa (Medicago sativa L), red clover (Trifolium pratense L), birdsfoot trefoil (Lotus corniculatus L), sainfoin (Onobrychis viciifolia Scop), crownvetch (Coronilla varia L), cicer milkvetch (Astragrlus cicer L), sericea lespedeza (Lespedeza cuneata (Dum-Cours) G Don) and kura clover (Trifolium ambiguum M Bieb) were subjected to sequential detergent fibre analysis to investigate the effects that the addition of sodium sulphite to neutral detergent has on the recovery and composition of fibre and lignin from forage legumes that vary in levels of proanthocyanidin (PA). Soluble, insoluble and neutral detergent insoluble PA (NDIPA) concentrations were highest in sericea, moderate in crownvetch, sainfoin and birdsfoot trefoil and absent in alfalfa, cicer milkvetch, red clover and kura clover. Addition of sodium sulphite reduced levels of neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), neutral detergent insoluble nitrogen (NDIN) and acid detergent insoluble nitrogen (ADIN) recovered from most forages tested. The addition of sodium sulphite effectively eliminated NDIPA from NDF. The difference between fibre fractions prepared without and with the addition of sodium sulphite during the neutral detergent procedure was related to PA concentration. Neutral detergent fibre difference was positively correlated with soluble PA (r = 0.730, p = 0.0001), insoluble PA (r = 0.905, p = 0.0001) and NDIPA (r = 0.913, p = 0.0001). Acid detergent fibre difference was positively correlated with soluble PA (r = 0.796, p = 0.0001), insoluble PA (r = 0.976, p = 0.0001) and NDIPA (r = 0.974, p = 0.0001). Acid detergent lignin difference was positively correlated with soluble PA (r = 0.846, p = 0.0001), insoluble PA (r = 0.992, p = 0.0001) and NDIPA (r = 0.972, p = 0.0001). Neutral detergent insoluble nitrogen difference was positively correlated with soluble PA (r = 0.475, p = 0.0255), insoluble PA (r = 0.579, p = 0.0047) and NDIPA (r = 0.570, p = 0.0056). Acid detergent insoluble nitrogen difference was positively correlated with soluble PA (r = 0.798, p = 0.0001), insoluble PA (r = 0.969, p = 0.0001) and NDIPA (r = 0.979, p = 0.0001). Sodium sulphite has large effects on fibre values of PA-containing species. Our results suggest that the difference between fibre fractions prepared with and without the addition of sulphite to neutral detergent may be used to determine the effects of PA on protein solubility in detergents. © 1999 Society of Chemical Industry     

果梅蜜饯中铝的污染来源分析及控制措施

目的 了解以果梅为原料生产的蜜饯中铝污染来源和水平, 探寻蜜饯中铝污染的关键环节。方法 采集生产企业加工用的原料、辅料、添加剂、加工过程中半成品及成品等样本, 利用电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry, ICP-MS)测定其中铝含量, 采用SPSS 26.0对其中铝残留量进行统计分析, 提出相应的铝污染控制措施。结果 加工用辅料、添加剂、生产用水中铝残留量较低, 83份果梅本底铝含量范围为17.54~156.32 mg/kg, 平均值为(44.99±23.28) mg/kg, 中位数为38.00 mg/kg, 超过50 mg/kg的样本占比24.1% (20/83)。盐腌制、糖腌制加工对样本中铝残留量差异有统计学意义(P<0.05), 不同场所加工的雕梅中铝残留量差异有统计学意义(Z=-2.005, P=0.045), 不同类别蜜饯中铝残留量差异有统计学意义(H=12.718, P=0.005)。结论 果梅原料中含有一定量本底铝值, 盐腌制加工可能是话化类蜜饯中铝污染的主要来源, 糖腌制加工降低了蜜饯中铝的残留量, 使用含铝添加剂可能是糖腌制蜜饯中铝的主要来源, 开展蜜饯中铝污染来源调查和风险防控时, 建议加强对相应环节的控制, 减少蜜饯中铝污染的来源。     

Comparison of ion-specific electrode and high performance liquid chromatography methods for the determination of iodide in milk

Two methods for the determination of I⁻ in raw and processed milk were examined. A simple ion-specific electrode (ISE) method was compared against a more complex HPLC reference technique. Accuracy and precision were evaluated both within and between the 2 methods. Both methods yielded good recoveries for Ion spiked samples, ranging from 87 to 114% for ISE and 91 to 100% for HPLC. Within-run repeatability and between-run reproducibility were superior with the HPLC method, but were still more than acceptable with the ISE technique. Overall agreement of paired results between ISE and HPLC methods was good (r² = 0.85 on raw herd milk; r² = 0.84 on processed milk). The ISE method had a significant positive bias relative to the HPLC reference method. Both methods lend themselves well to the measurement of I⁻ in raw or processed milk. Given its relatively low cost and ease of use, the ISE method is well suited as a screening method. The impressive accuracy, precision, selectivity, and limit of detection of the HPLC technique make it an ideal confirmation method.     

Development of a system to quantify muscle fibre destructuration

The aim of this study was to set up a method to quantify the loss or modification of muscle fibre structure (destructuration). Thanks to histology and image analysis, we managed to set up a reliable method with an uncertainty of 3.2%. To express the results, a new indicator called MDI (Meat Destructuration Indicator), was calibrated according to mechanically recovered meat market practices. The MDI indicator was strongly correlated (0.95) with the sensory assessment of a European panel (126 professionals). The threshold between raw materials that could be labelled as “meat” in processed products and mechanically separated meat (MSM) has been set at 58.1%, according to the panellist’s judgements. Thus MDI system can be used to characterise meat raw materials from mechanical recovery system according to Regulation (EC) No. 853/2004. It can also be used to study relationships between manufacturing parameters and destructuration or between destructuration of raw materials and processed products characteristics.     

Validation of a gold standard method for iodine quantification in raw and processed milk,and its variation in different dairy species

Adequate milk consumption significantly contributes to meeting the human iodine recommended daily intake, which ranges from 70 µg/d for infants to 200 µg/d for lactating women. The fulfilment of iodine recommended daily intake is fundamental to prevent serious clinical diseases such as cretinism in infants and goiter in adults. In the present study iodine content was measured in raw and processed commercial cow milk, as well as in raw buffalo, goat, sheep, and donkey milk. Iodine extraction was based on 0.6% (vol/vol) ammonia, whereas iodine detection and quantification were carried out through an inductively coupled plasma mass spectrometer analyzer. Among processed commercial cow milk, partially skimmed pasteurized milk had the greatest iodine content (359.42 µg/kg) and raw milk the lowest (166.92 µg/kg). With regard to the other dairy species, the greatest iodine content was found in raw goat milk (575.42 µg/kg), followed by raw buffalo (229.82 µg/kg), sheep (192.64 µg/kg), and donkey milk (7.06 µg/kg). Repeatability of milk iodine content, calculated as relative standard deviation of 5 measurements within a day or operator, ranged from 0.96 to 1.84% and 0.72 to 1.16%, respectively. The overall reproducibility of milk iodine content, calculated as relative standard deviation of 45 measurements across 3 d of analyses and 3 operators, was 4.01%. These results underline the precision of the proposed analytical method for the determination of iodine content in milk.     

Size exclusion and reversed-phase high-performance liquid chromatography/UV for routine control of thermal processing of cows' and donkey milk major proteins

Cows' and donkey milks (raw and thermally processed) and respective whey were analysed for quantification of major proteins. Two different chromatographic approaches, size exclusion (SE-HPLC) and reversed-phase high performance liquid chromatography (RP-HPLC) both coupled to UV detection were used. Usefulness of these methods for routine control of the effect of thermal processing was evaluated. The external standard method was used to calibrate the SE-HPLC and RP-HPLC systems. Concerning quantification of β-lactoglobulin (β-lg), α-lactalbumin (α-la), lysozyme (lys), and total casein (cn), no significant differences between results obtained by SE-HPLC and by RP-HPLC (t-test, P>0·05) were observed for raw milks and whey. Heating of cows' milk promoted aggregation of denatured proteins as observed by SE-HPLC, whereas α-la and β-lg from donkey milk were stable to thermal processing at 100 °C (5 min). Lys was quantified in donkey raw milk and whey however, in thermally processed donkey milk lys was denatured and could not be quantified by HPLC.     

PROCESSING AND FUNCTIONAL PROPERTIES OF YAM BEANS (SPHENOSTYLIS STENOCARPA)

The proximate and selected functional properties of five flours from yam bean (YB) made after the grains were not processed (raw) and processed as boiled, fermented, roasted and malted, were determined. The functional properties were water and fat absorption, gelation, emulsification and whippability. An improvement was observed for protein content of flours processed beans compared to raw flour. Fermentation improved the oil content of the flour. The emulsifying and foaming capacities (50.7 and 40.20%, respectively) observed for raw flour were significantly higher than those for the flours from processed bean. Gelation was significantly (P < 0.05) increased and decreased by fermentation and malting of the bean, respectively. The water absorption capacities ranged from 131.9% in raw flour to 218.8% in flour boiled beans. There were no significant (P > 0.05) differences in the fat absorption capacities of all flours except for the one of fermented beans (0.40 mL/g), which was significantly lower than the value (0.73 mL/g) obtained for the flour from boiled beans. Although a high foaming capacity was observed for raw flour, it was less stable when compared with that of the processed bean flours. Overall, YB flour was found to exhibit good functional properties, and has a great potential for use as an ingredient in selected food systems.     

基于体外模拟消化模型评价刺参中3种拟除虫菊酯的生物可给性

目的 评估刺参中拟除虫菊酯的生物可给性,为海产品中农药残留的监管提供参考。方法 基于胃相动态pH的体外模拟消化模型,采用气相色谱法分析加工前后刺参(Stichopus japonicas)中3种拟除虫菊酯(甲氰菊酯、氯氰菊酯和溴氰菊酯)的含量。结果 加工组与原料组相比,经过胃相消化后,3种菊酯类含量均显著降低(P<0.05);不管是原料组还是加工组,与消化前相比,经过肠道模拟消化后,3种菊酯浓度均显著降低(P<0.05);原料组中甲氰菊酯,氯氰菊酯和溴氰菊酯的生物可给性分别为63.09%,86.67%和71.83%,除了溴氰菊酯,加工后另外两种菊酯类生物可给性均低于原料组。结论 本研究结果表明刺参中3种拟除虫菊酯经模拟消化后均不能从食物基质中完全释放,此外加热处理可以在一定程度上降低刺参中拟除虫菊酯的生物可给性。     

Effect of Processing and Storage on Antioxidant Capacity of Honey

ABSTRACT: The impact of heat and filtration on the antioxidant capacity of clover and buckwheat honey during storage was analyzed. Processing clover honey did not significantly impact antioxidant capacity (determined by oxygen radical absorbance capacity [ORAC] assay); processing lowered the antioxidant capacity of buckwheat honey (33.4%). The antioxidant capacity of honeys was reduced after 6 mo of storage with no impact of storage temperature or container type detected at the end point of the storage period. Processed and raw clover honey antioxidant capacity decreased about 30%. Processed buckwheat honey decreased 24% in antioxidant capacity, whereas raw buckwheat honey decreased 49%. Antioxidant capacity of processed and raw honeys was similar after storage. Phenolic profiles, peroxide accumulation, 5-(hydroxymethyl)-2-furaldehyde (HMF), gluconic acid, and total phenolics were also analyzed. The impact of storage on antioxidant components of processed and raw honey was complex.     

Accuracy and precision of total mixed rations fed on commercial dairy farms

Despite the significant time and effort spent formulating total mixed rations (TMR), it is evident that the ration delivered by the producer and that consumed by the cow may not accurately reflect that originally formulated. The objectives of this study were to (1) determine how TMR fed agrees with or differs from TMR formulation (accuracy), (2) determine daily variability in physical and chemical characteristics of TMR delivered (precision), and (3) investigate the relationship between daily variability in ration characteristics and group-average measures of productivity [dry matter intake (DMI), milk yield, milk components, efficiency, and feed sorting] on commercial dairy farms. Twenty-two commercial freestall herds were visited for 7 consecutive days in both summer and winter months. Fresh and refusal feed samples were collected daily to assess particle size distribution, dry matter, and chemical composition. Milk test data, including yield, fat, and protein were collected from a coinciding Dairy Herd Improvement test. Multivariable mixed-effect regression models were used to analyze associations between productivity measures and daily ration variability, measured as coefficient of variation (CV) over 7 d. The average TMR [crude protein = 16.5%, net energy for lactation (NE_L) = 1.7 Mcal/kg, nonfiber carbohydrates = 41.3%, total digestible nutrients = 73.3%, neutral detergent fiber = 31.3%, acid detergent fiber = 20.5%, Ca = 0.92%, p = 0.42%, Mg = 0.35%, K = 1.45%, Na = 0.41%] delivered exceeded TMR formulation for NE_L (+0.05 Mcal/kg), nonfiber carbohydrates (+1.2%), acid detergent fiber (+0.7%), Ca (+0.08%), P (+0.02%), Mg (+0.02%), and K (+0.04%) and underfed crude protein (−0.4%), neutral detergent fiber (−0.6%), and Na (−0.1%). Dietary measures with high day-to-day CV were average feed refusal rate (CV = 74%), percent long particles (CV = 16%), percent medium particles (CV = 7.7%), percent short particles (CV = 6.1%), percent fine particles (CV = 13%), Ca (CV = 7.7%), Mg (CV = 5.2%), and Na (CV = 10%). Every 0.5-percentage-point decrease in daily NE_L (CV = 1.2 ± 0.4%) was associated with 3.2 kg/d greater milk yield, 1.0 kg/d greater DMI, and 4.3% greater efficiency of production. Every 5-percentage-point decrease in variability in percent long particles (average percent long = 19.8 ± 6.5; CV = 16.1 ± 6.9%) in the TMR was associated with 1.2 kg/d greater milk yield and a 2.6% increase in efficiency of milk production. These results demonstrate the importance of ensuring TMR consistency to maximize DMI, production, and efficiency.