Near-Infrared Spectroscopy (NIRS) as a Tool for Classification of Pre-Sliced Iberian Salchichón, Modified Atmosphere Packaged (MAP) According to the Official Commercial Categories of Raw Meat.

This study evaluates near-infrared spectroscopy (NIRS) feasibility in combination with various pre-treatments and chemometric approaches for pre-sliced Iberian salchichón under modified atmosphere (MAP) classification according to the official commercial category (defined by the combination of genotype and feeding regime) of the raw material used for its manufacturing (Black and Red purebred Iberian and Iberian × Duroc crossed (50%) pigs, respectively, reared outdoors in a Montanera system and White Iberian × Duroc crossed (50%) pigs with feed based on commercial fodder) without opening the package. In parallel, NIRS feasibility in combination with partial least squares regression (PLSR) to predict main quality traits was assessed. The best-fitting models developed by means of partial least squares discriminant analysis (PLS-DA) and linear discriminant analysis (LDA) yielded high discriminant ability and thus offered a tool to support the assignment of pre-sliced MAP Iberian salchichón according to the commercial category of the raw material. In addition, good predictive ability for C18:3 n-3 was obtained, which may help to support quality control.

Effect of Breed Purity and Rearing Systems on the Stability of Sliced Iberian Dry-Cured Ham Stored in Modified Atmosphere and Vacuum Packaging.

The long-term storage stability of three quality categories of sliced Iberian dry-cured ham defined by the Spanish Iberian Quality Standard (Black, purebred Iberian reared outdoors in Montanera system; Red, Iberian × Duroc crossed (50%) pigs reared outdoors in Montanera system;, and White, Iberian × Duroc crossed (50%) pigs commercially fed) and packaged under vacuum and modified atmosphere packaging (MAP) was studied. Commercial category affected the shelf life, being Black and Red presented the highest lipid oxidation during storage, whereas the effect of packaging was not as clear as the effect of commercial category. MAP preserved more the colour and the antioxidants content than vacuum packaging, while this latter reduced lipid oxidation development and maintained better the brightness and flavour of slices than MAP.

Near infrared spectroscopy (NIRS) as tool for classification into official commercial categories and shelf-life storage times of pre-sliced modified atmosphere packaged Iberian dry-cured loin.

The potential of Near Infrared Spectroscopy combining different spectral treatments and classification models was assessed for the classification of individual pre-sliced Iberian dry-cured loin packaged under modified atmosphere packaging (MAP) into three official commercial categories (which involve the breed purity and production system) according to the current Iberian Quality Standard (Black, Red and White) and for the assignment to the shelf-life time (0, 4, 8 and 12 months). External validation results provided acceptable results, with up to 100% of samples correctly assigned to Black and White official commercial category and into all storage times. Actually the 100% assignments were obtained using more than one approach (SIMCA and LDA for commercial categories and PLS-DA, SIMCA and LDA for storage times). These results might contribute to support the on-line control of authenticity of official commercial category and to facilitate the monitoring of the quality of pre-package dry-cured products throughout the shelf-life prediction.

Quality Traits of Dry-Cured Loins from Iberian Pigs Reared in Montanera System as Affected by Pre-Freezing Cure.

Iberian dry-cured loins from pigs fattened in Montanera are usually subjected to seasonal production, which could be overcome through freezing the loin before the curing process. Hence, three homogeneous batches (n = 15 per batch) were established to evaluate the effect of different pre-freezing cure (-20 ± 2 °C) times (three and six months) of raw material on main quality characteristics of dry-cured loins in comparison to those elaborated from unfrozen meat. All samples were subjected to similar seasoning and same curing length to obtain dry-cured loins. Results showed a decrease in lightness, redness, chrome and hue values, polyunsaturated fatty acids (PUFA), higher oxidative phenomena, and changes in rheological properties in fresh loins on account on freezing (p ≤ 0.05). Some quality parameters of dry-cured loins were affected by freezing, weight loss, and hardness being higher as well as salt content being lower. PUFA and Warner-Braztler Shear Force (p ≤ 0.05) also showed higher values in dry-cured loins from frozen meat than those elaborated from unfrozen counterparts.

Impact of high pressure processing on color, bioactive compounds, polyphenol oxidase activity, and microbiological attributes of pumpkin purée.

Physicochemical parameters, bioactive compounds' content (carotenoids and total phenols), total antioxidant activity, and enzymatic activity of polyphenol oxidase (PPO) were evaluated after high pressure processing (HPP) on a pumpkin purée (cv. 'Butternut'). Three pressure levels (400, 500, and 600 MPa) were combined with three holding times (200, 400, and 600 s). The applied treatments reduced the levels of total aerobic mesophilic (TAM), total psychrophilic and psychrotrophic bacteria (TPP), and molds and yeasts (M&Y). All applied treatments did not affect enzymatic activity of PPO. Pressure level increased CIE L* values, which could enhance the lightness perception of high pressure (HP)-treated purées. No differences were found between the untreated and HP-treated purées regarding total phenols and carotenoids content (lutein, α-carotene, and ß-carotene) and total antioxidant activity. HPP did not affect most quality parameters and maintained the levels of bioactive compounds. However, it did not achieve the complete inhibition of PPO, which could reduce the shelf-life of the pumpkin purée.

Effect of processing by hydrostatic high pressure of two ready to heat vegetable meals and stability after refrigerated storage.

The effect of high pressure processing (HPP) (400 and 600 MPa for 1 and 5 min) and the stability during storage were studied in two ready to heat vegetable meals: meal A, mainly composed by pumpkin and broccoli, and meal B, mainly composed by eggplant, zucchini, chard and spinach. The treatment at 600 MPa/5 min was the most effective to reduce the initial microbial loads of the meals and maintained better the microbial safety during storage. HPP had no effect on the physico-chemical and sensory properties. HPP at 600 MPa increased the antioxidant activity of the meal A. In contrast HPP reduced the antioxidant activity of the meal B, although in general high levels of antioxidants were maintained after processing and during storage. In conclusion, treatments at 600 MPa for 5 min were the most suitable to increase the shelf-life of the meals without affecting their physico-chemical, antioxidant and sensory properties.

Effect of high-pressure processing and thermal treatment on quality attributes and nutritional compounds of "Songold" plum purée.

UNLABELLED: The application of hydrostatic high pressure on a "Songold" plum purée was assessed in comparison with heat pasteurization. To simulate industrial conditions, one-half of the total purée was manufactured with a pretreatment of thermal blanching (TB) and the other half without it (nonthermally blanched, NTB). Changes after thermal treatment and high-pressure processing (HPP: 400, 600 MPa) and after 20 d of refrigerated storage were evaluated. HPP maintained the microbial stability of the purées until the end of the storage period. Polyphenol oxidase activity was lower in TB purées than NTB purées. No treatment was completely effective to stop the enzyme activity, although a significant reduction was reached. Thermally treated purées showed more intense color changes after processing and storage than HP-treated purées. After processing, high-pressure (HP) purées treated at 600 MPa (TB and NTB) increased the extractability of carotenoids compared with initial untreated purée. Nevertheless, at the end of the storage, the highest carotenoid content was found in the TB purée treated at 400 MPa. After processing, total polyphenol levels were similar in all purées. TB and 600 MPa processing was more effective in the maintenance of the polyphenols than the other purées. TB increased the level of antioxidants after storage, compared to NTB purées. A previous TB step is necessary to inactivate browning enzymes before HPP to maintain the levels of bioactive compounds. HPP of plum purée could be a suitable alternative to traditional thermal processing, but more studies are necessary to ensure a major inactivation of polyphenol oxidase. PRACTICAL APPLICATION: High-pressure processing is one of the most successful technologies to obtain high-quality fruit purées without appreciable losses in taste, flavor, color, and nutritive value. However, for the introduction of a new technology, some advantages compared to the traditional thermal treatment need to be emphasized. The application of this technology could be reduced due to resistance of certain enzymes to pressurization. For this reason, in some cases the application of a previous thermal blanching can be necessary at industrial level. However, this can reduce the advantages of HPP application. This paper provides interesting information about the storage stability of plum purées after high-pressure treatments and assesses the need for applying heat pretreatments.