Nine varieties of lotus root (Suining, Xinhe, Zaohua, Zhonghua, L0014, L0013, Cuiyu, L0011, and Zhenzhu) were selected as the research materials to compare their differences in physical, chemical, and starch characteristics before and after boiling, frying, and microwaving. The results showed that Zhenzhu, Xinhe, L0013, Cuiyu, and Zhonghua belong to the crispy lotus root type, while L0011, L0014, Zaohua, and Suining belong to the powdery lotus root type. Furthermore, the nine varieties were characterized for their starch by optical micrograph (OM), polarized micrograph (PM), scanning electron micrograph (SEM), attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), carbon-13 cross-polarization/magic angle spinning nuclear magnetic resonance (¹³C CP/MAS NMR), and differential scanning calorimetry (DSC). The starch granule of powdery lotus root appeared to be larger than that of crispy lotus, and ATR-FTIR studies revealed that the outer layer of starch granules from nine different varieties of lotus root had a highly organized structure. Moreover, XRD and ¹³C CP/MAS NMR analyses revealed that starch from eight lotus varieties (Suining, Xinhe, Zaohua, Zhonghua, L0014, L0013, Cuiyu, L0011) belong to the A-crystal type, while starch from Zhenzhu belongs to the C_A-crystal type. The starch from powdery lotus root exhibited higher crystallinity, as well as increased gelatinization temperature and enthalpy, indicating that its crystal structure was relatively superior compared to that of crispy lotus starch. The short-range order degree, crystallinity, gelatinization temperature, and heat enthalpy of lotus starch decreased after boiling and frying but increased to varying extents after microwaving. Additionally, the heat resistance and stability of starch particles from crispy lotus root were improved after microwave treatment.

To investigate the flavor characteristics of peanuts grown in Jiangsu, China, ten local varieties were selected. The amino acids, 5′-nucleotides and volatile substances were detected, and the flavor and odor characteristics of these varieties were estimated using an electronic tongue and nose. The results showed that the fat and protein contents of ten peanut varieties changed significantly (p < 0.05), and may have been negatively correlated with those of the Taihua 6 variety—in particular, having the highest protein content and the lowest fat content. The amino acid contents of the peanuts were 20.08 g/100 g (Taihua 4)–27.18 g/100 g (Taihua 6). Taihua 6 also contained the highest bitter (10.41 g/100 g) and sweet (6.06 g/100 g) amino acids, and Taihua 10 had the highest monosodium glutamate-like amino acids (7.61 g/100 g). The content of 5′-nucleotides ranged from 0.08 mg/g (Taihua 9725) to 0.14 mg/g (Taihua 0122–601). Additionally, 5′-cytidylate monophosphate (5′-CMP) and 5′-adenosine monophosphate (5′-AMP) were the major 5′-nucleotides detected in the peanuts. A total of 42 kinds of volatile flavor compounds were detected, with both Taihua 4 and 6 showing the most (18 kinds) and the highest content being in Taihua 4 (7.46%). Both Taihua 9725 and 9922 exhibited the fewest kinds (nine kinds) of volatile components, and the lowest content was in Taihua 9725 (3.15%). Formic acid hexyl ester was the most abundant volatile substance in peanuts, and the highest level (3.63%) was detected in Taihua 7506. The electronic tongue and nose indicated that the greatest taste difference among the ten varieties of peanuts was mainly related to sourness, and Taihua 4 and Taihua 9922 had special taste characteristics. On the other hand, the greatest smell difference among the ten varieties of peanuts was mostly for methane and sulfur organic substances, and Taihua 0605-2 had a special and strong smell characteristic. In conclusion, the content and composition differences of the flavor substances of ten peanut varieties were responsible for their divergences in taste and smell. These results will provide guidelines for the further use (freshly consumed or processed) of these ten peanut varieties.

Starch extracted from ten lotus root varieties (Yeyong, MRHZ, Zhonghua, Suiningbaiou, Zaohua, Meirenhong, E9:11, Huchengyeou, Peixianyeou, Xin No. 5) from Jiangsu Province, China, were studied. The structural characteristics of lotus root starch were analyzed based on its physical and chemical properties, particle structure, crystal structure, layered structure, thermal properties and gel properties. The lotus root starches were generally milky white, with a starch content ranging from 81.72 to 99.54%, amylose content ranging from 15.44 to 23.54%, light transmittance between 15.30 and 26.90%, and swelling power and solubility at 22.15–29.72% and 2.00–6.00%, respectively. Among the varieties, “Suiningbaiou” had the whitest starch, while “Meirenhong” and “Suiningbaiou” had higher starch contents. “Huchengyeou” had the lowest amylose content, and “Zhonghua” showed the highest light transmittance. “Yeyong” and “Zaohua” had higher solubility, whereas “Zhonghua” had the highest swelling power. An optical, polarizing and scanning electron microscope revealed that most of the lotus starch was oval. However, starch from “Zhonghua”, “E9:11”, “Peixianyeou” and “Zaohua” was longer, whereas starch from “Meirenhong”, “MRHZ”, “Huchengyeou”, “Yeyong”, “Suiningbaiou” and “Xin No.5” was shorter. The X-ray powder diffraction patterns and ¹³C NMR spectroscopy indicated that “Zaohua” starch exhibited type A crystallization, while starch from the other varieties displayed type C_A crystallization, with a relative crystallinity between 18.27 and 22.10%; “Huchengyeou” and “Yeyong” had higher crystallinity. Infrared spectroscopy and small-angle X diffraction analysis showed similar results for short-range order and lamella spacing. The thermal and gel properties of starch from the ten lotus root varieties also varied. The enthalpy change values of “Xin No.5” and “Yeyong” were higher, and starch from “Yeyong” and “Huchengyeou” showed a greater gel strength. Finally, factor score analysis ranked the starch quality of the top four lotus root varieties in Jiangsu as “Suiningbaiou”, “Yeyong”, “Huchengyeou”, and “Zaohua”.