红烧肉烹饪工艺及其影响因素研究

采用正交试验,对扬州家常红烧肉的烹制过程中的色拉油、酱油、黄酒和白砂糖的基本配比以及加水量、焖焙温度、焖焙时间等工艺参数进行优化研究。结果表明,家常红烧肉最佳配比为：五花肉1000g：盐6g：葱20g：姜20g：色拉油100g：老抽王40g：黄酒100g：白砂糖40g;其烹制过程为：将1000g五花肉煸炒出油,加水300g大火烧开后,选用锅底温度100℃焖焙60min,最后大火收汁,这样烹制的红烧肉综合感官评价得分最高。     

笋干菜糯米营养保健香肠的开发研究

研究了笋干菜营养香肠的生产工艺,探讨了影响其质量的因素:笋干菜的添加量、糯米的添加量、糯米的颗粒度及肥、瘦肉的比例。并在此基础上采用正交实验得出了最佳工艺条件和配比,结果表明:五花猪肉79%,糯米用量15%,笋干菜用量6%,肥、瘦肉比例2:8,糯米颗粒度30目时香肠质量最佳。     

Effects of onion on physicochemical properties,lipid oxidation and microbial growth of fresh pork patties

Onions with or without heating (100 °C, 30 min) were extracted with water or methanol, and antioxidant and antimicrobial activities of onion extracts were evaluated. Product characteristics of fresh pork patties containing various onion extracts were measured during refrigerated storage. Water extracts of onions showed higher extraction yield and iron chelating ability than methanol extracts (P < 0.05), whereas, the latter was more effective than the former in phenolic compounds and reducing power (P < 0.05). The addition of onion extracts [water extract from fresh onion (WEFO), methanol extract from heated onion (MEHO) and their combinations (WEFMEHO)] to pork patties decreased redness, increased yellowness, and inhibited lipid peroxidation (P < 0.05). One per cent of WEFMEHO in pork patties had antioxidant activities as effective as butylated hydroxyl toluene (BHT, 0.01%). Redness and yellowness decreased and increased with the addition of onion extract, respectively (P < 0.05).     

Evaluation of pre‐heating and extraction solvents in antioxidant and antimicrobial activities of garlic,and their application in fresh pork patties

The objectives of this study were to screen the optimum conditions for antioxidant and antimicrobial activities of garlic as affected by pre‐heating and different extraction solvents, and to evaluate the antioxidant and antimicrobial effects of these extracts in ground meat during refrigerated storage. Methanol extracted garlic had a greater total phenolic content, 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH)‐radical scavenging activity and reducing power than water extracted one (P < 0.05), whereas the latter had a greater yield and iron chelating ability than the former (P < 0.05). Moreover, water extract from fresh garlic (WEFG) and methanol extract from heated garlic (MEHG) produced an inhibition zone against Escherichia coli O157:H7 and Listeria monocytogenes. The addition of garlic extracts (WEFG, MEHG and their combinations WEFMEHG)) to pork patties decreased the pH, hunter a values (redness), thiobarbituric acid substances values and the number of total plate count and Enterobacteriaceae (P < 0.05), while the hunter b values (yellowness) increased (P < 0.05). Results of this study indicated that the use of the garlic extracts was able to control lipid oxidation and microbial growth in pork patties.     

Nutritional quality of model low‐fat pork patties manufactured with the use of soy protein isolate

Proximate composition and amino acid and fatty acid profiles of low‐fat pork patties manufactured with the addition of soy protein isolate (SPI) were determined and their energy values were calculated. Patties with SPI were characterised by a higher content of protein than the control. Although the 10% SPI added sample showed the highest energy value of all samples, it contained the lowest amount of fat and therefore the share of energy from the fat of this sample was lower than those of the other samples. The essential amino acid indices of SPI added patties were lower than those of the control, but they were still favourable compared to the FAO/WHO/UNU reference pattern of protein. The fatty acid composition of fat was positively influenced by the addition of SPI, as an increase in C18:2, C18:3, total PUFA and PUFA/SFA ratio along with an increased amount of SPI added to patties was observed.     

Effects of Eubacterium coprostanoligenes and Lactobacillus on pH, Lipid Content, and Cholesterol of Fermented Pork and Mutton Sausage-Type Mixes

Pork and mutton sausage-type mixes produced using Eubacterium coprostanoligenes with or without Lactobacillus as starter culture showed changes in pH, cholesterol and lipid content. Viability of E. coprostanoligenes was assessed by culturing samples from each treatment and analyzing for coprostanol, a cholesterol metabolite. The pH and/or cholesterol decreased (P < 0.05) in the sausage-type mixes inoculated with E. coprostanoligenes or Lactobacillus or their combinations. Variability in lipid content was observed among and within treatments. Very low (6.2 μg/g dry matter) concentrations of coprostanol were produced in sausage-mixes and cultures except when inoculated with 2.0 g of E. coprostanoligenes (from 8.2 to 130.6 μg/g dry matter).     

Thermal Inactivation of Salmonella spp. in Chicken Broth, Beef, Pork, Turkey, and Chicken: Determination of D- and Z-values

ABSTRACT: The heat resistance of 35 Salmonella strains was determined at 55 to 65°C. No correlation between the heat resistance and the origin of the Salmonella spp. could be established. D-values in chicken broth, using a linear regression, of an 8 Salmonella serotype cocktail were 4.87, 2.72, 1.30, and 0.41 min at 55, 58, 60 and 62°C, respectively. Using a linear model, the D-values ranged from 4.86 min at 55°C to 0.38 min at 62°C. When the 8 Salmonella serotype cocktail was heated in meat, D-values at the common test temperatures of 58 and 60°C calculated by both approaches were significantly higher (p < 0.05) than those observed in chicken broth.     

Freeze/thaw Stability of Cooked Pork Sausages as Affected by Salt, Phosphate, pH, and Carrageenan

The effects of κ, ι, or λ carrageenan (CGN), sodium tripolyphosphate (STPP), chloride salts, and meat pH on the freeze/thaw stability of cooked pork sausages were investigated. STPP decreased thaw drip (TD) and increased hardness for all treatments regardless of type of salt or CGN. KCI did not affect the texture of control samples in the presence of STPP, but decreased the functionality of κ- and ι-CGN. Increased meat pH increased the hardness and decreased thaw drip for all CGN treatments, except for λ-CGN, which remained unchanged. k- and ι- CGN increased moisture retention of sausages prepared from low-pH meat.     

Simulation of human exposure to benzylpenicillin residues via pork originating from pigs fed with a dairy by-product

The use of food industry by-products for feeding is restricted by European Union by-product regulation (1774/2002). However, the actual public health risks involved in the use of such products are poorly recognized. This study focuses on bovine milk rejected at the dairy because of a positive result in antimicrobial drug testing and thereafter used as feed for finisher pigs in Finland. In theory, this current practice could expose pork consumers to antimicrobial drug residues. Raw bulk milk samples originating from rejected lots were analysed with a multiresidue method detecting five beta-lactams, including benzylpenicillin. Based on the probabilistic simulation model developed, concentrations of benzylpenicillin in pork invariably remained below 1% of the maximum residue limit. Therefore, the use of this by-product as feed with the current practice was considered to pose only a negligible risk to consumers of pork products.     

Effect of irradiation and modified atmosphere packaging on the microbiological and sensory quality of pork stored at refrigeration temperatures

The effect of combining low-dose irradiation (1.75 kGy) with modified atmosphere packaging (MAP) on the microbiological and sensory quality of pork chops stored at refrigeration temperatures was studied. The microflora of irradiated MAP pork was almost exclusively composed of lactic acid bacteria, predominantly Lactobacillus spp. Modified atmospheres containing either 25 or 50% CO₂, balance N₂, resulted in the best microbial control in irradiated pork held at 4°C, compared to an unirradiated MAP control, and these atmospheres were subsequently used in sensory studies. The atmosphere containing 25% CO₂ 75% N₂ maintained the uncooked colour and odour of irradiated pork chops more effectively than 50% CO₂ 50% N₂. Therefore packaging in a modified atmosphere containing 25% CO₂, balance N₂, followed by irradiation to a dose of 1.75 kGy is recommended to improve the microbiological and sensory quality of pork chops.