Classification of traditional Chinese pork bacon based on physicochemical properties and chemometric techniques
Introduction
Pork bacons are a class of traditional meat products in China. According to the Columbia Encyclopedia, bacon is made of hog flesh, particularly from the sides, belly, or back, that has been preserved by being salted or pickled and then dried with or without wood smoke. Traditional Chinese pork bacon possesses a long history in China, especially in the southern part, because of its distinct flavor, such as tangy, delicate, meaty, and salty, and its particular texture that appeals to Chinese consumers. At present, traditional Chinese pork bacon is being introduced worldwide (Yu et al., 2008). A variety of Chinese traditional pork bacon styles exist in China, but Hunan, Sichuan, Guangdong, Jiangxi, and Yunnan styles are most widely known. The characteristics for each category are associated with the variety of pork reared in particular areas, the distinctive processing of products, climate, and dietary habit of most local residents.
Presently, more and more traditional Chinese products become labeled with their geographical origins. Geographical classification is helpful for branding strategy purposes to help consumers select their food items (Ariyama et al., 2012). As a representative traditional Chinese meat product, numerous categories of traditional Chinese bacon can be included, and their characteristics are closely related to their production areas. Classifying the different styles of traditional Chinese pork bacon is important to qualify the particular aroma, taste, and special nutritional properties these varieties possess that make them preferable for more consumers (Cubadda et al., 2006, Galgano et al., 2008, Joebstl et al., 2010, Kelly et al., 2005, Lo Feudo et al., 2010, Spalla et al., 2009). Recent developments in chemometric techniques present great use in characterizing and classifying food products (Arvanitoyannis et al., 2005, Berrueta et al., 2007, Cantarelli et al., 2011, Chudzinska and Baralkiewicz, 2011, Kelly et al., 2005, Popek, 2002, Tzouros and Arvanitoyannis, 2001). Several analytical methods, such as principal component analysis (PCA) and linear discriminant analysis (LDA), have been applied as comprehensive methods based on chemometric techniques to analyze the classification of honey and determine of the geographic origin of rice, potatoes, olive oil, and Pecorino cheese, as well as to discriminate sweet wines (Ariyama et al., 2012, Benincasa et al., 2007, Cevoli et al., 2011, Di Giacomo et al., 2007, García-Martínez et al., 2011, NozalNalda et al., 2005). The physicochemical properties of Guangdong-style traditional Chinese pork bacon have been analyzed by several researchers. However, similar analyses have yet to be used in other styles of traditional Chinese pork bacon, so the physicochemical properties of other styles have not been understood to date. In particular cases, Krauze and Zalewski (1991) used principal component analysis to evaluate certain physicochemical characteristics as implements for the classification of honey from different botanical origins. In addition, 13 common physicochemical determination methods of honey samples from the various production zones of three styles in western Spain were analyzed for their geographical classification. Classifications of 70.1% and 76.0% were correctly made using discriminate analysis (Gómez Bárez et al., 2000, Krauze and Zalewski, 1991). However, few reports focused on the classification of traditional Chinese bacon, and classification methods are unavailable. Thus, selecting products according to their preference when purchasing becomes difficult for customers. Thus, establishment of a method or system to identify different styles of traditional Chinese pork bacon is necessary. The application of physicochemical determination methods combined with chemometric techniques can classify traditional Chinese bacon into five different styles and provide a discriminate equation as a standard database for bacon classification. However, these methods have not been currently used for Chinese pork bacon. The present study aims to classify traditional Chinese traditional pork bacon manufactured in five provinces of south China through physicochemical determinations. Given the varieties of pork, products processed in different areas, climates, and personal taste preferences of native citizens affecting the physicochemical properties of traditional Chinese bacon, nine physicochemical determinations, used as evaluation indicators for traditional Chinese bacon, were examined for subsequent classification. The application of PCA and DA to physicochemical determination properties will be used for classifying five different styles of traditional Chinese pork bacon and providing a discriminant equation as a standard database for the geographical classification of bacon.
Section snippets
Traditional Chinese pork bacon samples
A total of 67 different brand samples of traditional Chinese pork bacon were purchased at local commercial stores or exclusive shops in the provinces of Hunan, Sichuan, Guangdong, Jiangxi, and Yunnan (Table 1). The shelf life of the purchased samples was one month after product date. Each 500 g sample was sealed in vacuum packages and stored at 4 °C before testing.
Analytical determinations
The samples were ground for subsequent analysis, and nine physicochemical parameters, which included acid value, pH, peroxide value
Difference analysis
Means, standard errors (SEM), and ranges for nine physicochemical properties are listed in Table 2, and the statistical differences of these parameters among styles were investigated using ANOVA. Results show that the acid value of Hunan-style bacon was the highest and that of Yunnan style bacon was the lowest among the five bacon styles. However, no significant difference (P > 0.05) was found for this value. Additionally, POV and the sugar content of Guangdong-style bacon were higher than those
Conclusion
The classification of traditional Chinese pork bacon was carried out by employing physicochemical determination. Traditional Chinese pork bacon samples were differentiated by utilizing DA and PCA. Our results showed significant differences in physicochemical determinations among different styles and separation properties among Guangdong-style, Sichuan-style, and Hunan-style bacon. DA on tested samples provided a strong discriminant function for traditional Chinese pork bacon. A percentage of
Acknowledgments
This research was funded by the National Key Technology Support Program (Grant No.: 2014BAD04B02-03) and the Special Fund for Agro-scientific Research in the Public Interest (Grant No.: 201303082-4).The authors wish to thank Dr. Hong Yan from Sichuan Tourism College for her help during sampling.
References (25)
- et al.
Determination of trace element in Italian virgin olive oils and their characterization according to geographical origin by statistical analysis
Analytica Chimica Acta
(2007) - et al.
Supervised pattern recognition in food analysis
Journal of Chromatography A
(2007) - et al.
Identification of components of Brazilian honey by 1H NMR and classification of its botanical origin by chemometric methods
LWT - Food Science and Technology
(2012) - et al.
Trace mineral content of Argentinean raw propolis by neutron activation analysis (NAA): Assessment of geographical provenance by chemometrics
LWT - Food Science and Technology
(2011) - et al.
Classification of pecorino cheeses using electronic nose combined with artificial neural network and comparison with GC–MS analysis of volatile compounds
Food Chemistry
(2011) - et al.
Application of ICP-MS method of determination of 15 elements in honey with chemometric approach for the verification of their authenticity
Food and Chemical Toxicology
(2011) - et al.
Analysis of trace elements in southern Italian wines and their classification according to provenance
LWT - Food Science and Technology
(2008) - et al.
Discrimination of sweet wines partially fermented by two osmo-ethanol-tolerant yeasts by gas chromatographic analysis and electronic nose
Food Chemistry
(2011) - et al.
Identification of the geographical origin of pumpkin seed oil by the use of rare earth elements and discriminant analysis
Food Chemistry
(2010) - et al.
Tracing the geographical origin of food: The application of multi-element and multi-isotope analysis
Trends in Food Science & Technology
(2005)
Stable isotope analysis of cattle tail hair: A potential tool for verifying the geographical origin of beef
Food Chemistry
A procedure to identify a honey type
Food Chemistry
Cited by (0)
- 1
Both authors contributed equally to the work.