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Novel freezing solutions are constantly being developed to reduce quality loss in meat production chains. However, there is limited focus on identifying the sensitive analytical tools needed to directly validate product changes that result from potential improvements in freezing technology. To benchmark analytical tools relevant to meat research and production, we froze pork samples using traditional (−25 °C, −35 °C) and cryogenic freezing (−196 °C). Three classes of analyses were tested for their capacity to separate different freeze treatments: thaw loss testing, bioelectrical spectroscopy (nuclear magnetic resonance, microwave, bioimpedance) and low-temperature microscopy (cryo-SEM). A general effect of freeze treatment was detected with all bioelectrical methods. Yet, only cryo-SEM resolved quality differences between all freeze treatments, not only between cryogenic and traditional freezing. The detection sensitivity with cryo-SEM may be explained by testing meat directly in the frozen state without prior defrosting. We discuss advantages, shortcomings and cost factors in using analytical tools for quality monitoring in the meat sector.

This study was performed to test bioimpedance as a tool to detect the effect of different thawing methods on meat quality to aid in the eventual creation of an electric impedance-based food quality monitoring system. The electric impedance was measured for fresh pork, thawed pork, and during quick and slow thawing. A clear difference was observed between fresh and thawed samples for both impedance parameters. Impedance was different between the fresh and the frozen-thawed samples, but there were no impedance differences between frozen-thawed samples and the ones that were frozen-thawed and then stored at +3 °C for an additional 16 h after thawing. The phase angle was also different between fresh and the frozen-thawed samples. At high frequency, there were small, but clear phase angle differences between frozen-thawed samples and the samples that were frozen-thawed and subsequently stored for more than 16 h at +3 °C. Furthermore, the deep learning model LSTM-RNN (long short-term memory recurrent neural network) was found to be a promising way to classify the different methods of thawing.

Previous studies proposed that electric and magnetic fields can affect the freezing of biological tissues, including meat. Yet, improved freezing through sole magnetic or combined electro-magnetic field exposure is disputed. Also, as previous studies typically tested very small sample dimensions, it is unclear if the reported effects are transferrable to larger product sizes that are relevant to commercial food freezing. Here we aimed at reassessing previous findings by constructing and testing a scaled-up setup for applying electric and magnetic fields during freezing. Importantly, our setup replicates key technical aspects of previous electro-magnetic freezer designs. We modeled and measured the spatial distribution of electric and magnetic fields generated by this setup. We then studied possible effects of field exposure on freezing of two different volumes of saline water and of meat. We tested four different field treatments: sole magnetic and electric field exposure, a combination of both and a control without altered field exposure. We show that the 20 kHz square wave electric field was largely homogenous, while the static 0.2 T magnetic field was not. We found that none of the field treatments altered freezing dynamics of the three tested sample types. Our findings, hence, do not support previous data obtained with similar electro-magnetic field freezer setups. We discuss how our study that uses very distinct field parameters, may inform the general discussion on the effectiveness of electro-magnetic field exposure during food freezing.

The lean meat percentage (LMP) classification in Norwegian slaughterhouses is obtained by Hennessy Grading Probe 7 (HGP7), an optical tool. Even though the HGP7 method is validated frequently, there is industrial and legislative demand to reconsider the applied LMP equation, typically due to the introduction of new breeds. A deboning pilot plant generates precise yield data using cutting and deboning stratified pork carcasses by a specific commercial cutting pattern (CCP) at an annual rate of approximately 250 slaughter pigs. This paper shows how results obtained by CCP can be used to measure LMP in pork and how these results can be used for monitoring the quality of LMP predicted by HGP7. The effect of gender, maternal- and paternal lines on validity of HGP7 predictions was evaluated. The effect of introducing a new maternal line (TN70) seems to be substantial, whereas the effects of the tested paternal lines are small to negligible.

In 2006, the European Commission approved nutrition and health claim regulations of foods to stimulate healthier choices. To document how commercial, minced beef meat complied with regulations, meat samples from 72 carcasses were analysed. These samples were a source of niacin (B3), pyridoxine (B6), phosphorus and iron (cow meat only), and a rich source of protein, monounsaturated fat, vitamin B12 and zinc. A potential exists for establishing beef meat as a source of vitamin K, iron and selenium. The meat's nutrient relevance for young women when ingesting 150 g of raw beef mince/day was estimated. Increased levels of riboflavin (B2), pantothenic acid (B5), iron and selenium beyond presently observed, would better support this group's recommended nutrient intake. If the bioactivity of 25-OH-vitamin D3 could be used in calculations, vitamin D3 in the minced meat would add positively to the intake of vitamin D3 that was 49% of the recommended intake.

A system for on-line sorting of meat trimmings into categories with different fat levels was developed and tested by simulations and pilot-plant trials. The system consists of a conveyor belt, a NIR imaging scanner (QV500, Tomra Sorting Solutions, Asker, Norway), a flow weigher and grader (both Marel hf, Iceland) and a host computer containing synchronising software and a sorting algorithm. The sorting algorithm is based on desirability functions, which makes it flexible when it comes to selecting number of categories, target values, limits for deviations and other restrictions. The results showed that the sorting algorithm works when the fat measurements are accurate, giving deviations from target lower than the selected ±1 percentage point limits. In reality there are some inaccuracies in the on-line fat measurements due to inhomogeneous meat trimmings. This leads to a systematic under-estimation of the fat percentage in low-fat categories and over-estimation in the high-fat categories. These biases can be reduced by e.g. improving the on-line fat measurement technology. However, simulations showed that the bias for either category was generally low (below 2 percentage points) and the current system therefore has potential for on-line implementation.

BACKGROUND: Retention of nutrients in vegetables during blanching/freezing, cooking and warm-holding is crucial in the preparation of both standard and therapeutic diets. In the present study, conventional cooking in water, and cooking by pouch technology (boil-in-bag, sousvide) were compared in their ability to retain vitamin C, total phenolics and antioxidative activity (DPPH and FRAP) in industrially blanched/frozen tip-cut green beans and swede rods. RESULTS: After conventional cooking, 50.4% total ascorbic acid, 76.7% total phenolics, 55.7% DPPH and 59.0% FRAP were recovered in the drained beans. After boil-in-bag cooking, significantly (P < 0.05) higher recoveries were obtained, i.e. 80.5% total ascorbic acid, 89.2% total phenolics, 94.8% DPPH and 92.9% FRAP. Recoveries aftersousvide cooking were comparable to those of boil-in-bag cooking. By conventional cooking, 13.5 – 42.8% of the nutrients leaked into the cooking water; bysousvide about 10% leaked to the exuded liquid, while no leakage occurred by boil-in-bag cooking. Warm-holding beans after cooking reduced recoveries in all components. Recoveries in swede rods were comparable but overall slightly lower. CONCLUSION: Industrially blanched/frozen vegetables should preferably be cooked by pouch technology, rather than conventional cooking in water. Including cooking water or exuded liquid into the final dish will increase the level of nutrients in a meal. Warm-holding of vegetables after cooking should be avoided. c � 2010 Society of Chemical Industry

In this paper we present a user-friendly multivariate optimization methodology based on visual inspection of contour plots of selected optimization criteria. Several possibilities exist when choosing optimization criteria, but we focus on the overall closeness to target (quadratic form), its robustness, the maximum individual deviation from target (i.e. the worst optimized response) and the empirical variance of the individual deviations from target. The approach assumes that there exist models relating the input variables to the responses, and that the responses have certain desirable target values. The methodology is general but particularly useful when the number of control variables is low and the responses to be optimized are many. In cases with several control variables, conditional contour plots can be used. We demonstrate the use of the methodology with two examples from the food industry. The examples show that the different criteria do not necessarily predict the same optimum and that weighing of the individual quadratic deviations from target (using an inverse covariance matrix) can be important if the responses are strongly correlated.

A screening experiment consisting of 18 batches of meat loaves were made using a fractional factorial design with six factors including two production replicates i.e. testing of several factors in relatively few trials. The rancidity was detected by TBARS, volatile compounds by GC-MS and sensory analysis by a sensory panel. The results were presented graphically as formal statistical testing is limited. To do this the multivariate results from GC-MS and sensory analyses were made univariate by statistical tools. Pre-salting meat and storing it in frozen air, will result in rancid meat, and regardless pre-salting or not ascorbic acid will act as a pro-oxidant when added into already rancid meat and stored frozen. The three methods used to detect rancidity in meat loaves resulted sometimes in discrepancy in the results. Further research has to be done to verify if these findings were due to development of different oxidation products due to the combinations of factors or if these were outliers.

A multistage production development project on low-fat mayonnaise is described. A pilot plant study of all stages of the production process was undertaken using three alternative empirical modeling approaches to analyze data. A combination of graphical ..

In all experimental situations, handling variability properly is important in order to achieve reliable and informative experimental results. The benefits from 'design of experiments' are well known to most experimentalists, but this article emphasizes the more practical matters of planning and performing experiments. Poor control of the variation sources in the experimental situation will generally lead to poor results. Three important statistical tools for handling variability in experiments are presented--replication, blocking and randomization. These tools are discussed in examples of real experiments, to illustrate the practical aspects of statistical thinking. In this context, statistical thinking may be viewed as utilizing common sense before it becomes belated wisdom. The illustrative examples may be viewed as failures, and not worthy of publishing, but in this context they are useful for illustrating commonly occurring obstacles and mistakes in experimental work.

The area of mixture design and analysis is of vital importance in food science and industry, since all foods are mixtures of a number of different ingredients. Mixture methods respect constraints among the ingredients in both the set-up of the design and the analysis of the results. This methodology is, therefore, more complex than, e.g., factorial and fractional factorial designs. Projection design methodology as proposed by Hau and Box [I.Hau, G. Box, Constrained experimental designs: Part I. Construction of projection designs, I, Center for Quality and Productivity Improvement, University of Wisconsin, Madison, WI, USA, 1990; I. Hau, G. Box, Constrained experimental designs: Part II. Analysis of projection designs, II, Center for Quality and Productivity Improvement, University of Wisconsin, Madison, WI, USA, 1990; I. Hau, G. Box, Constrained experimental designs: Part III. Properties of projection designs, III, Center for Quality and Productivity Improvement, University of Wisconsin, Madison, WI, USA, 1990] is developed to keep some of the simplicity of the factorial approach while working with the more complex area of mixture designs and constrained situations in general. The method is based on setting up a fractional factorial design and then projecting this onto a space determined by the set of constraints. In some cases, the analysis can also be done by “factorial-like” techniques. In the present paper, the projection design method is investigated and compared with the more conventional mixture model method [J.A. Cornell, Experiments with Mixtures. Designs, Models and the Analysis of Mixture Data, 2nd edn., 1990, Wiley-Interscience]. The discussion is based on a case study where process and mixture variables are combined. Both design and modelling aspects are discussed. The overall conclusion is that both approaches are useful. However, the mixture model approach seems somewhat more flexible with respect to design region and also somewhat easier to analyse and interpret. The projection design approach seems to be a useful and simple way of providing fractional versions of combined designs. This may be difficult by using other techniques.

This paper compares design and analysis techniques for mixtures. The main focus is on comparing a statistical treatment taking the mixture aspect fully into account and another where only a subset of the mixture variables is considered both in the design phase and during analysis. Mixture techniques are of special importance for product development and optimization of food products and processes. The methods are tested on data from a baking experiment where three flours were mixed in different proportions and the different flours were baked in three different process conditions. The example is of importance for understanding the relationship between flour quality, baking process and bread quality. The main conclusion is that treating the design as a true mixture design and analyzing the data in terms of all variables involved is advantageous compared to a treatment where only a subset of the mixture variables is considered. ©

A fat and weight sorting system for heterogeneous meat trimmings has been developed. The system is based on a non-contact NIR interactance scanner, a flow weight and a sorting belt, combined with multiresponse optimization algorithms.

Pieces of prerigor salmon fillets were packaged in modified atmosphere (60% CO(2) and 40% N(2)) and in vacuum. The MA packages had a gas to product volume ratio (g/p ratio) of 3/1 (traditional MAP) and 1/1 (packaged with a CO(2) emitter). All the samples were stored at 1.2 degrees C for 25 d. The MA packages had lower bacterial growth during storage compared to vacuum packages. The analyses of 16S rRNA at day 22 indicated a similar bacterial diversity, independent of packaging methods, dominated by Photobacterium phosphoreum. The results therefore suggest that CO(2) inhibited total bacterial count, including, P. phosphoreum. Negative odors and liquid losses were detected earlier for the vacuum-packaged samples (8 d) compared to the MA samples (15 d) and higher levels were detected at the end of the storage period. The breaking strength (firmness) tended to be lower for the MA packaged samples compared with the vacuum samples after 15 d of storage, whereas the redness (a* value) and the yellowness (b* value) were significantly higher for the MA samples. In conclusion, MA packaging preserved the quality better during storage than vacuum packaging. MA packaging with a CO(2) emitter and reduced g/p ratio gave similar or better results compared with traditional MAP, thus CO(2) emitters are well suited for reduction of volume of MA packaged farmed salmon fillet pieces.